WO2023183190A1

WO2023183190A1 - Fluid heater

Info

Publication number: WO2023183190A1
Application number: PCT/US2023/015466
Authority: WO
Inventors: Hector Joel Castaneda
Original assignee: White Knight Fluid Handling Inc.
Priority date: 2022-03-24
Filing date: 2023-03-17
Publication date: 2023-09-28

Abstract

A fluid heater is configured to increase the temperature of a process fluid flowing through the fluid heater. The fluid heater includes multiple tubes that route the process fluid through the fluid heater. One or more heaters are disposed radially inward of the tubes such that the thermal energy generated by the heaters radiates outwards to heat the process fluid.

Description

FLUID HEATER

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to U.S. Provisional Application No. 63/323,103 filed March 24, 2022 and entitled “FLUID HEATER,” the disclosure of which is hereby incorporated by reference in its entirety.

BACKGROUND

The present disclosure relates generally to a fluid heater. More specifically, the present disclosure relates to fluid heaters for use in semiconductor fabrication.

Fluid heaters are configured to heat fluids, such as liquids. For example, the fluid heater can be utilized to heat liquid, such as solvent, during fabrication of semiconductors. Solvents in semiconductor fabrication fall into two categories — non-hazardous and hazardous. In semiconductor fabrication, the purity of the heated fluid must be maintained while responsively adding and maintaining heat in the fluid.

SUMMARY

According to an aspect of the disclosure, a fluid heater configured to increase a temperature of a process fluid includes a heater housing elongate along an axis between a first housing end and a second housing end; a first manifold assembly disposed within the heater housing and in fluid communication with a fluid inlet of the fluid heater; a second manifold assembly disposed within the heater housing and in fluid communication with a fluid outlet of the fluid heater; a plurality of tubes extending within the heater housing between the first manifold assembly and the second manifold assembly to fluidly connect the first manifold assembly and the second manifold assembly; and at least one heater located within the heater housing, wherein the plurality of tubes are arrayed radially outward of the at least one heater.

According to an additional or alternative aspect of the disclosure, a fluid heater configured to increase a temperature of a process fluid includes a heater housing elongate along an axis between a first housing end and a second housing end; a first manifold assembly disposed within the heater housing and in fluid communication with a fluid inlet; a second manifold assembly disposed within the heater housing and in fluid communication with a fluid outlet; a core disposed within the heater housing axially between the first manifold assembly and the second manifold assembly, wherein the core is formed from a plurality of blocks stacked axially, the plurality of blocks being thermally conductive; a plurality of tubes extending through the core between the first manifold assembly and the second manifold assembly to fluidly connect the first manifold assembly and the second manifold assembly; and at least one heater located within the core radially inward of the plurality of tubes.

According to another additional or alternative aspect of the disclosure, a fluid heater configured to increase a temperature of a process fluid includes a heater housing elongate along an axis between a first housing end and a second housing end; a first manifold assembly disposed within the heater housing and in fluid communication with a first fluid port formed by one of a fluid inlet and a fluid outlet; a second manifold assembly disposed within the heater housing and in fluid communication with a second fluid port formed by the other one of the fluid inlet and the fluid outlet; a core disposed within the heater housing axially between the first manifold assembly and the second manifold assembly; a plurality of tubes extending through the core; and at least one heater located within the core radially inward of the plurality of tubes. The first manifold includes a first inner manifold having a first plurality of fluid apertures extending therethrough; a first outer manifold having a first port aperture extending therethrough, the first outer manifold in fluid communication with the first fluid port through the first port aperture; and a first flow chamber formed between the first inner manifold and the first outer manifold, the first flow chamber providing fluid communication between the first port aperture and the first plurality of fluid apertures. The plurality of tubes extend between the first plurality of fluid apertures and the second manifold assembly to fluidly connect the first flow chamber and the second manifold assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an isometric view of a fluid heater.

FIG. IB is a cross-sectional view taken along line B-B in FIG. 1A.

FIG. 2 is a cross-sectional view taken along line B-B in FIG. 1A with the end caps and outer housing removed.

FIG. 3 is an exploded view of the fluid heater.

FIG. 4 is an exploded view of a fluid handling and heating portion of the fluid heater.

FIG. 5 is an enlarged cross-sectional view of an end portion of a fluid heater.

FIG. 6A is a first isometric view of an inner manifold of a manifold assembly.

FIG. 6B is a second isometric view of the inner manifold of the manifold assembly.

FIG. 7A is a first isometric view of an outer manifold of a manifold assembly.

FIG. 7B is a second isometric view of the outer manifold of the manifold assembly.

FIG. 8A is an isometric view of a first end block of a core.

FIG. 8B is an isometric view of a second end block of the core.

FIG. 9 is a cross-sectional view of a fluid heater. FIG. 10 is a cross-sectional view of a fluid heater.

DETAILED DESCRIPTION

The present disclosure generally concerns fluid heaters. For example, the fluid heaters of the present disclosure can be utilized for heating fluids utilized in semiconductor fabrication. Such a fluid heater can be utilized to heat liquid solvent, among other options. Fluid heaters according to the present disclosure include discrete passages for routing the fluid through the fluid heater. The fluid heater further includes internal heaters that generate heat to be applied to the fluid. The heaters are disposed inward from the discrete passages such that the heat radiates outward from the heater to the fluid.

Components can be considered to radially overlap when those components are disposed at common axial locations along an axis. A radial line extending orthogonally from axis will extend through each of the radially overlapping components. Components can be considered to axially overlap when those components are disposed at common radial and circumferential locations relative to the axis. An axial line parallel to the axis will extend through the axially overlapping components. Components can be considered to circumferentially overlap when aligned about the axis, such that a circle centered on the axis passes through the circumferentially overlapping components.

FIG. 1A is an isometric view of fluid heater 10. FIG. IB is a cross-sectional view of fluid heater 10 taken along line B-B in FIG. 1A. FIGS. 1A and IB will be discussed together. Fluid heater 10 includes heater housing 12; end caps 14a, 14b; feet 16; fluid ports 18a, 18b; purge ports 20; electrical port 22; manifold assemblies 24; core 26; insulation 28; clamps 30; tubes 32; heaters 34; and sensors 36a-36c (referred to collectively herein “sensor 36” or “sensors 36”). Core 26 includes end blocks 27a, 27b and intermediate blocks 27c (end blocks 27a, 27b and intermediate blocks 27c referred to collectively as “block 27” or “blocks 27”).

Fluid heater 10 is configured to receive a process fluid, such as a liquid for semiconductor manufacturing, through one of fluid ports 18a, 18b and to emit the process fluid through the other one of fluid ports 18a, 18b. Fluid heater 10 increases a temperature of the process fluid flowing between fluid ports 18a, 18b. Fluid heater 10 can be configured to raise the temperature of any desired process fluid, including volatile, combustible solvents. Fluid heater 10 can be utilized to heat the solvent. Fluid heater 10 can be utilized to heat Isopropyl alcohol (IP A), DuPont™ PlasmaSolv® EKC (e.g., EKC265, EKC830, EKC270), Acetone, Ethanol, Toluene, methyl ethyl ketone (MEK), N-Methyl-2-pyrrolidone (NMP), among others. Fluid heater 10 can be utilized in various applications, such as semiconductor manufacturing. Some examples of fluid heater 10 can be utilized in explosive environments. For example, fluid heater 10 can be utilized in Division I hazardous locations, Class I, Division II hazardous locations, etc. In some examples, fluid heater 10 can heat the process fluid to about 120°C (about 248°F) when utilized in hazardous locations. In some examples, fluid heater 10 can heat the process fluid to about 180°C (about 356°F) when utilized in non-hazardous locations.

Fluid heater 10 is generally elongate along axis AA. Axis AA is indicated along the elongate orientation of the fluid heater 10. Axis AA is generally coaxial with the cylindrical body of the fluid heater 10. Radial direction R is also generally shown, it being understood that a radial direction can be any direction orthogonal to the axis AA. In the example shown, the heater housing 12 is coaxial with the axis AA.

Heater housing 12 encloses other components of fluid heater 10. Heater housing 12 can be formed of metal, among other options. As shown, fluid heater 10 is generally cylindrical. The heater housing 12 may be tubular. The heater housing 12 can be cylindrical and disposed coaxial with the axis AA. End cap 14a is disposed at a first axial end of fluid heater 10 and end cap 14b is disposed at a second axial end of fluid heater 10. End caps 14a, 14b interface with heater housing 12 to define an exterior of fluid heater 10.

Fluid ports 18a, 18b are configured to admit process fluid into and route process fluid out of fluid heater 10. Fluid port 18a is disposed on a first end of the fluid heater 10. The fluid port 18a can be configured as an inlet or an outlet for the inflow or outflow of process fluid from the fluid heater 10. Fluid port 18b is disposed on a second end of the fluid heater 10. The fluid port 18b can be the other one of an inlet or an outlet for the inflow or outflow of process fluid from the fluid heater 10. Fluid port 18b is generally the opposite of that of the fluid port 18a such that process fluid flows into the fluid heater 10 from either fluid port 18a, 18b and flows out of the fluid heater 10 from the other fluid port 18 a, 18b.

In the example shown, fluid port 18a is configured as the inlet one of the fluid ports 18a, 18b and fluid port 18b is configured as the outlet one of the fluid ports 18a, 18b. Fluid port 18a is configured to be vertically lower than fluid port 18b in the example shown. Such a configuration encourages flow of the process fluid through the flowpaths that are disposed circumferentially about core 26, as discussed in more detail below.

In the example shown, fluid port 18a extends through the end cap 14a. Fluid port 18a includes a fitting 38a extending through end cap 14a in this example. In the example shown, fluid port 18b extends through the end cap 14b. Fluid port 18b includes a fitting 38b extending through end cap 14b in this example. The fittings 38a, 38b can be mechanically connected to the respective end caps 14a, 14b such that the end cap 14a, 14b supports the fitting 38a, 38b. The fittings 38a, 38b interface with the manifold assemblies 24 to form a fluid connection for passing of process fluid between the manifold assembly 24 and the fitting 38. In some examples, the fitting 38a, 38b is not fixedly connected to the manifold assembly 24. For example, the fittings 38a, 38b can be threadedly connected to the end caps 14a, 14b and can interface with the manifold assembly 24 at a contact seal. In some examples, a sealing element, such as a crush seal, can be disposed between the fitting 38a, 38b and the manifold assembly 24. The fitting 38a can be disposed at a bottom dead center location of end cap 14a and the fitting 38b can be disposed at a top dead center of end cap 14b.

Leak sensor 37 is configured to sense a leak of the process fluid. Leak sensor 37 can be mounted proximate the inlet one of fluid ports 18a, 18b. In the example shown, leak sensor 37 is disposed proximate fluid port 18a. Leak sensor 37 can be configured as a fiber optic sensor, among other options.

The fluid heater 10 includes electrical port 22. Electrical port 22 is formed on the second end of fluid heater 10. Electrical port 22 extends through end cap 14b and provides a passage through which electrical wiring can extend to the interior of fluid heater 10. While electrical port 22 is shown as extending though end cap 14a, it is understood that electrical port 22 can be disposed at other locations on fluid heater 10, such as a on end cap 14b, among other options. Electrical port 22 includes fitting 38c that is directly connected to end cap 14b. Fitting 38c is mounted to end cap 14b to be supported by end cap 14b. The electrical wires extend through fitting 38c. Fitting 38c does not interface with a manifold assembly 24. Insulation 28 is disposed directly between electrical port 22 and fitting 38c in the example shown.

The fluid heater 10 includes purge ports 20. Purge ports 20 provide openings through which a purge fluid, such as an inert gas (e.g., nitrogen), can flow into and out of the interior of fluid heater 10. The purge gas is flowed through fluid heater 10 to purge oxygen from the interior of fluid heater 10, providing an inert environment to inhibit combustion. The purge gas can enter into a purge pathway 40 through a purge port 20 on one end cap 14a, 14b and exit the purge pathway 40 through a purge port 20 on the other end cap 14a, 14b. In the example shown, the axial portion of the purge pathway 40 is formed radially within heater housing 12 and radially outward of core 26. The purge pathway 40 is radially narrow and does not extend within core 26. A radial thickness, taken along a radial line extending in one direction away from the axis AA, of the purge pathway 40 is less than a radial thickness of the insulation 28. A radial thickness of the purge pathway 40 is less than a radial thickness of the core 26. The narrow purge pathway 40 reduces the volume of purge gas required to effectively purge the interior of fluid heater 10. In the example shown, a plurality of purge ports 20 are formed on end cap 14a and a single purge port 20 is formed on end cap 14b. It is understood, however, that not all examples are so limited. For example, end caps 14a, 14b can include the same number of purge ports 20 or end cap 14b can include a greater number of purge ports 20 than end cap 14a. In the example shown, a first one of the purge ports 20 on end cap 14b forms one of an inlet and an outlet for the purge fluid and the purge port 20 on end cap 14a forms the other one of the inlet and the outlet for the purge fluid to flow through purge pathway 40 in fluid heater 10. The second one of the purge ports 20 on end cap 14b forms a sensor port through which a pressure of the purge gas can be measured. The purge gas flowing through fluid heater 10 is configured to prevent accumulation of combustible fumes. In the example shown, the purge port 20 on end cap 14b is configured as the inlet port for the purge gas and the purge port 20 on end cap 14a is configured as the outlet port for the purge gas. The purge pathway 40 can be configured with the outlet purge port 20 further from feet 16 than inlet purge port 20. Purge gas (e.g., nitrogen gas) is lighter than air so positioning the inlet purge port 20 below the outlet port 20 facilitates purge flow.

In the example shown, the purge gas flows in a different axial direction through fluid heater 10 as compared to the process fluid. In the example shown, the process fluid flows in a first axial direction along the axis AA from fluid port 18a to fluid port 18b while the purge gas flows in an opposite second axial direction along the axis AA from the purge port 20 on end cap 14b to the purge port 20 on end cap 14a.

Feet 16 are configured to support fluid heater 10 on a support surface. In the example shown, fluid heater 10 includes a pair of feet 16 respectively located on the first and second axial ends of the fluid heater 10. In this particular example, the feet 16 are mounted to the end cap 14a and to the end cap 14b. In this particular example, the feet 16 are not mounted to the heater housing 12. However, the feet 16 can be mounted to the heater housing 12 in various alternative examples. In the example shown, feet 16 can be mounted to any desired surface. Feet 16 can be mounted on a horizontal surface such that fluid heater 10 is oriented horizontally. Feet 16 can be mounted on a vertical surface such that fluid heater 10 is oriented vertically.

Core 26 is disposed within heater housing 12. The core 26 is elongate and extends along the axis AA. In the example shown, the core 26 extends coaxial with the axis AA. The core 26 can include a cylindrical exterior. The core 26 includes one or more blocks 27. The blocks 27 are thermally conductive. The blocks 27 can be formed from metal, such as aluminum or other metal, to readily conduct heat. In this particular example, a plurality of blocks 27 are stacked along the axis AA. In this example, the blocks 27 are coaxial with the axis AA. The blocks 27 can be formed with generally circular exterior surfaces. While the core 26 is made up of an axial stack of blocks 27 in various examples, it is understood that some examples can include a single block 27 used to form the main body of core 26.

In the example shown, core 26 is formed from end blocks 27 a, 27b and intermediate blocks 27. End blocks 27a, 27b are disposed at the axial ends of core 26 and form the axial- most blocks 27 of core 26. Intermediate blocks 27c are disposed between end block 27a and end block 27b. End block 27a is disposed at the first axial end of fluid heater 10 and is axially between end cap 14a and intermediate blocks 27c. End block 27b is disposed at the second axial end of fluid heater 10 and is axially between end cap 14b and intermediate blocks 27c. While core 26 is shown as including intermediate blocks 27c, it is understood that not all examples are so limited. For example, core 26 can be configured with end block 27a disposed adjacent to end block 27b without intervening intermediate blocks 27c.

Clamps 30 are disposed at least partially around the core 26. In the example shown, fluid heater 10 includes a pair of clamps 30 that interface with end blocks 27a, 27b. Clamps 30 are configured to interface with heater housing 12 and core 26 to axially locate core 26 within heater housing 12.

Insulation 28 is disposed around core 26. Insulation 28 is disposed between core 26 and heater housing 12. Insulation 28 can be formed by silicon foam, among other options. In the example shown, insulation 28 is formed by multiple insulating layers stacked together. In the example shown, portions of the insulation 28 extend radially to axially overlap with the core 26. The radially extending portions of insulation 28 are disposed axially outward from end blocks 27a, 27b. the radially extending portions of insulation 28 are disposed between the manifold assemblies 24 and the end caps 14a, 14b. The core 26 is disposed axially between the radially extending portions of insulation 28. In the example shown, the portions of insulation 28 axially overlapping with core 26 are disposed axially outside of manifold assemblies 24 such that manifold assemblies 24 are disposed axially between those radially extending portions of the insulation 28. The insulation 28 also wraps around core 26 to radially overlap with core 26.

Extending within the core 26 are a plurality of tubes 32. The plurality of tubes 32 are configured to carry the process fluid between the inlet one of the fluid ports 18a, 18b and the outlet one of the fluid ports 18a, 18b. It is when the process fluid is flowing within the tubes 32 that the process fluid receives thermal energy to increase its temperature. The plurality of tubes 32 can be arrayed around the axis AA. The plurality of tubes 32 can be in a circular array. Such circular array may be coaxial with the axis AA, however not all embodiments are so limited. The tubes 32 can be disposed circumferentially about axis AA. In some examples, the tubes 32 can be disposed in arcuate groupings about the axis AA. Some examples of fluid heater 10 includes layered tubes 32 that can be radially multilayered, such that some of the tubes 32 are spaced radially from others of the tubes 32 (e.g., radially outward away from axis AA or radially inward towards axis AA.) In some examples, the tubes 32 can be multilayered such that one or more of the tubes 32 radially overlaps with one or more other ones of the tubes 32. The tubes 32 are formed from a polymer. For example, the tubes 32 can be formed from perfluoroalkoxy (PFA ) or other fluoropolymer, amongst other options.

The tubes 32 extend through the blocks 27. Each tube 32 of the plurality of tubes 32 can extend fully axially through each of the blocks 27. As such, tubes 32 can be considered to extend fully axially through the main body portion of core 26. In some examples, the tubes 32 can extend fully axially through core 26 and at least partially into manifold assembly 24. As such, a portion of each tube 32 can radially overlap with blocks 27 while other portions of the tubes 32 do not radially overlap with the blocks 27. The tubes 32 can extend straight through the blocks 27 such that the tubes 32 radially overlap with the blocks 27 but do not axially overlap with the blocks 27. Each tube 32 can extend elongate along a tube axis. The tube axis can be disposed parallel to the axis AA. Each tube axis can be disposed parallel to the other tube axes.

The tubes 32 extend through aligned bores through the blocks 27. Each series of aligned bores can be considered to form a tube passage through which a tube 32 extends. The material forming the blocks 27 extends radially inward and radially outward from the plurality of tubes 32. As such, tubes 32 are disposed radially within the thermally conductive material of the core 26 and radially outward of the thermally conductive material of the core 26.

One or more heaters 34 extend within the core 26. Heaters 34 are electrically powered. For example, heaters 34 can be resistive heaters, among other options. In the example shown, heaters 34 extend partially axially thought the core 26 but not fully axially through the core 26. It is understood, however, that not all examples are so limited. In the example shown, heaters 34 extend through aligned bores in the blocks 27. Each series of aligned bores can be considered to form a heater passage 44 within which a heater 34 extends. While one heater 34 is shown in FIG. IB, it is understood that fluid heater 10 can include one or more than one heaters 34 within the core 26. For example, fluid heater 10 can include one, two, three, or more heaters 34. In the example shown, one or more, up to all, of the heaters 34 extend parallel along the axis AA. The heaters 34 can be evenly arrayed around the axis AA. The heaters 34 can be evenly spaced away from axis AA. For example, an array of three heaters 34 can be spaced 120-degrees apart from each other about the axis AA. In the example shown, heaters 34 extend within each block 27 of core 26 to directly heat each block 27.

Extending within the core 26 are sensors 36. Sensors 36 can be thermal sensors that reactive to temperature changes. For example, sensors 36 can be configured to generate data regarding temperature. As shown in this example, the sensors 36 can extend within only one block 27. In the example shown, sensors 36 are disposed in end block 27b. However, in other examples one or more sensors 36 may extend through one or more blocks 27. Sensors 36 are disposed in sensor bores 56 that are formed within end block 27b. Sensor bores 56 do not extend fully axially through end block 27b and are not formed in any other block 27 than end block 27b in the example shown.

Sensors 36 may output signals received by a controller (not shown) to indicate temperature. In the example shown, sensors 36 include sensor 36a configured as a power modulator (PM) sensor, sensor 36b configured as an over-temperature (OT) sensor, and sensor 36c configured as an over-temperature (OT) snap switch. Sensor 36a can measure temperature and provide such information to a system controller. The system controller can regulate power to heaters 34 based on the data generated by sensor 36a. Sensor 36b is configured to generate temperature information regarding the temperature exceeding a preset limit and can be configured to initiate a shutdown process if the temperature threshold is exceeded. Sensor 36c is configured to shut down heaters 34 in the event of an overheat situation indicated by sensor 36b.

The controller is configured to control supply of electrical energy to heaters 34 to power the heaters 34 to produce heat. The controller may have a variable setpoint such that sensing of temperature below the setpoint causes the controller to power the heaters 34 to a greater degree to increase the temperature within the core 26 and sensing temperature above the setpoint causes a decrease or cessation of energy to the heaters 34 to reduce the temperature of the core 26. In some cases, multiple setpoints may be used with multiple of the different sensors 36 for taking different actions depending on which setpoint associated with which sensor 36 was crossed (e.g., a first upper setpoint for PM sensor 36a to cause a decrease in power to decrease temperature, a first lower setpoint for PM sensor 36a to cause an increase in power to increase temperature, and a second upper setpoint greater than the first upper setpoint for OT sensor 36b to cause shutdown of fluid heater 10).

Blocks 27 can be configured similarly to facilitate assembly of fluid heater 10 and to provide for a modular configuration that can be assembled together to form fluid heaters 34 having differing axial lengths. In the example shown, the end blocks 27a, 27b, which are disposed at the axial ends of core 26, are individually configured while the various intermediate blocks 27c are collectively configured. In the example shown, end block 27a is differently configured from end block 27b and intermediate blocks 27c; end block 27b is differently configured from intermediate blocks 27c; and each intermediate block 27c is configured the same as the other intermediate blocks 27c. Tube passages 42 are formed by the tube bores that extend fully axially through each block 27 such that tubes 32 extend fully axially through core 26.

End block 27a includes heater bores that extend fully through the end block 27a. End block 27b includes heater bore that extend only partially axially through end block 27b. The heater bores of end block 27b include a closed end such that heaters 34 do not extend fully axially through the end block 27b. One end of the heater bores through end block 27b is closed. End block 27b further includes sensor bores 56 for the various sensors 36 of fluid heater 10. End block 27b is open for heaters 34 on a first axial side of end block 27b and closed for heaters 34 on a second axial side of end block 27b. End block 27b is open for sensors 36 on the second axial side of end block 27b and closed for sensors 36 on the first axial side of end block 27b.

Intermediate blocks 27c bridge the axial gap between end blocks 27a, 27b. It is understood that various examples can include end block 27a adjacent to and interfacing with end block 27b (providing a fluid heater 10 having a minimum axial length). Heater bores extend fully axially through each intermediate block 27c.

Manifold assemblies 24 are located on the first axial end and second axial end of the fluid heater 10. The manifold assemblies 24 are configured to receive the process fluid entering through a first one of the fluid ports 18a, 18b and route the process fluid to the second one of the fluid ports 18a, 18b that outputs the process fluid. Each manifold assembly 24 connects with the plurality of tubes 32. The manifold assemblies 24 are fluidly connected to the tubes 32 to provide process fluid to or receive process fluid from the tubes 32. The tubes 32 can extend into the manifold assembly 24 to directly interface with the manifold assembly 24. The plurality of tubes 32 connect with both of the manifold assemblies 24. An upstream manifold assembly 24 receives the process fluid from a fluid port 18a, 18b and provides the process fluid to tubes 32. A downstream manifold assembly 24 receives the process fluid from tubes 32 and provides the process fluid to the other fluid port 18a, 18b.

One of manifold assemblies 24 is disposed at each axial end of the core 26. The pair of manifold assemblies 24 bracket opposite ends of the core 26. In the example shown, the pair of manifold assemblies 24 axially bracket the axial stack of blocks 27. Manifold assemblies 24 are disposed within heater housing 12. Manifold assemblies 24 are disposed directly axially between end caps 14a, 14b. In the example shown, the core 26 is disposed axially between manifold assemblies 24. Sensors 36 are located between the pair of manifold assemblies 24. In the example shown, sensors 36 radially overlap with core 26. Sensors 36 do not radially overlap with manifold assemblies 24. Heaters 34 are located between the manifold assemblies 24. In the example shown, heaters 34 radially overlap with core 26. Heaters 34 do not radially overlap with manifold assemblies 24.

In the example shown, manifold assemblies 24 are formed as rings extending about the axis AA. In the example shown, each manifold assembly 24 is coaxial with the axis AA, and the pair of manifold assemblies 24 are arrayed coaxial with the axis AA. It is understood, however, that not all examples are so limited. In the example shown, manifold assemblies 24 are formed as annular rings that extend about the axis AA. In the example shown, no portion of the manifold assemblies 24 is disposed on the axis AA to axially overlap with the axis AA, though it is understood that not all examples are so limited.

Each manifold assembly 24 defines a flow chamber 46 that routes the process fluid between the fluid port 18a, 18b associated with that manifold assembly 24 and the tubes 32. In the example shown, the flow chamber 46 extends annularly about the axis AA. The flow chamber 46 does not axially overlap with the axis AA such that the axis AA does not extend through the wet flow chamber 46. The flow chamber 46 is disposed about the axis AA and can, in some examples, be disposed coaxially with the axis AA. The flow chamber 46 can be an annular chamber that has fluid flow fully about the axis AA.

The manifold assemblies 24 each include a port aperture 48 that faces axially outward for fluid communication with a fluid port 18a, 18b. A fitting 38a, 38b can extend into port aperture 48 to interface with the manifold assembly 24. The manifold assembly 24 includes a single fluid pathway (facing axially outward) that fluidly connects with the fluid port 18a, 18b and includes multiple fluid pathways (facing axially inwards) that fluidly connects with the tubes 32. The flow chamber 46 can receive a single input and provide multiple outputs or receive multiple inputs and provide a single output.

During operation of fluid heater 10, and assuming that fluid port 18a is the inlet and fluid port 18b is the outlet for example purposes, the process fluid enters into fluid heater 10 through fluid port 18a. The process fluid flows into the flow chamber 46 of the upstream manifold assembly 24 interfacing with fluid port 18a through the port aperture 48 in that upstream manifold assembly 24. The process fluid flows within the flow chamber 46 to the tubes 32. The single inlet flow entering the flow chamber 46 of the upstream manifold assembly 24 is divided into a plurality of outlet flows from the flow chamber 46 of the upstream manifold assembly 24. The upstream manifold assembly 24 divides the inlet flow into a larger number of outlet flows than number of inlet flows. The outlet flows are provided to the tubes 32. The upstream manifold assembly 24 can be considered to form a flow divider.

The process fluid flows through the tubes 32 to the downstream manifold assembly 24. The process fluid enters into the flow chamber 46 of the downstream manifold assembly 24. The process fluid flows within flow chamber 46 to the fluid port 18b interfacing with the downstream manifold assembly 24 at the port aperture 48 of the downstream manifold assembly 24. The process fluid exits from fluid heater 10 through fluid port 18b. The plurality of inlet flows entering the flow chamber 46 of the downstream manifold assembly 24 are consolidated into a single outlet flow exiting from the flow chamber 46 of the downstream manifold assembly 24. The downstream manifold assembly 24 consolidates the multiple inlet flows into a smaller number of outlet flows than number of inlet flows. In the example shown, the downstream manifold assembly 24 consolidates the multiple inlet flows to a single output flow provided to fluid port 18b. The downstream manifold assembly 24 can be considered to form a flow consolidator.

In the example flowpath discussed above, the fluid port 18a forms the process fluid inlet of fluid heater 10 and fluid port 18b forms the process fluid outlet of fluid heater 10. The fluid port 18a is disposed vertically below the fluid port 18b in the example shown. In some examples, the fluid port 18a can be disposed at a bottom dead center location of end cap 14a and the fluid port 18b can be disposed at a top dead center location of end cap 14b. The process fluid filling into fluid heater 10 at a vertically lower location than the process fluid exiting from fluid heater 10 encourages degassing of fluid heater 10 on initial flow of the process fluid. The process fluid fills vertically upward, driving out gasses that may be in the fluid path as the manifold assemblies 24 and tubes 32 fill with the process fluid. In some examples, the fluid port 18a can be disposed at a bottom dead center location of end cap 14a and fluid port 18b can be disposed at a top dead center of end cap 14b. It is understood, however, that the flow can be reversed from that just described to reverse the inlet and outlet. For example, fluid port 18b can form the inlet and fluid port 18b can form the outlet.

The two manifold assemblies 24 can be identical or at least similar to each other as described, except that one is upstream of the other and divides process fluid flow into multiple channels while the other consolidates process fluid flow into one channel. During operation, one of manifold assemblies 24 receives a single input flow and outputs multiple flows to multiple channels, while the other one of manifold assemblies 24 receives multiple flows from multiple channels and outputs to a single output flow.

Each of the manifold assemblies 24 includes a center space 50. The center space 50 may be a void filled only by gas, however in various embodiments components can extend through the center space 50. For example, wiring for the heaters 34 and/or sensors 36 can extend through the center spaces 50 of the respective manifold assemblies 24. In this way, each manifold assembly 24 can be considered to define a wiring space. In the example shown, wires for heaters 34 extend through the center space 50 of the manifold assembly 24 connected to end block 27a and wires for sensors 36 extend through the center space 50 of the manifold assembly 24 connected to end block 27b.

End blocks 27a, 27b on the ends of the axial stack can include recesses 52. Wires may be routed through the recesses 52 to connect with the heater 34 and/or sensors 36. The recesses 52 can be considered to form wiring spaces. The recesses 52 extend axially within the main body portion of the end blocks 27a, 27b such that the ends of the sensors 36 and heaters 34 are recessed from the end faces of the end blocks 27a, 27b. Such a configuration provides for an axially compact fluid heater 10, reducing required space for installation and operation and reducing material costs. As shown, the heaters 34 may be only accessible through a first of the recesses 52 (formed by end block 27a) while the sensors 36 may only be accessible through a second of the recesses 52 (formed by end block 27b) on the opposite end of core 26 from the first recess 52. Having heaters 34 accessible from one axial end and sensors 36 accessible from the other axial end reduces electromagnetic interference that can affect the sensors 36, providing for more accurate data generated by and operation of sensors 36, thereby providing more efficient operation of fluid heater 10.

In some examples, potting material (e.g., epoxy) may be located within the recesses 52 to secure wiring or other electrical components. Embedding the electrical components within the potting material provides electrical insulation and protects the electrical components from short circuiting, dust, moisture, etc.

In the example shown, the blocks 27 include one or more mates 54. Mates 54 facilitate securement of the plurality of blocks 27 relative to one another. Mates 54 can also perform sealing functions to seal potential leaks from the plurality of tubes 32 from penetrating radially inward towards the heaters 34 and/or sensors 36. Mates 54 can be formed as alternating projections and recesses. The recesses on one block 27 are configured to receive the projections from an adjacent block 27. In some examples, each block 27 may include ones or more recesses on one axial end and/or one or more projections on the other axial end for mating with adjacent blocks 27. The one or more recesses and mating projections can extend partially or fully about the axis AA. The one or more recesses can be formed as an annular recess, one or more arcuate recesses, etc. The one or more projections can be formed as an annular projections, one or more arcuate projections, etc.

In the example shown, the intermediate blocks 27c each include mates 54 formed on both axial ends of the intermediate block 27c. The end blocks 27a, 27b include one mate 54 due to only being adjacent to one other block 27. The mates 54 of the end blocks 27a, 27b are oriented axially inward towards the intermediate blocks 27c to interface with the mates 54 of the intermediate blocks 27c. In the example shown, each of the projecting mates 54 is oriented in a first direction along axis AA and each of the recessed mates 54 is oriented in an opposite second direction along axis AA.

Heaters 34 are located radially within the plurality of tubes 32. In this way, heat flows radially outward from the heaters 34 to the plurality of tubes 32. The heaters 34 are not located radially outward of the plurality of tubes 32. No heat generating element is disposed radially outward of the tubes 32 in the example shown. In the example shown, most or essentially all of the heat generated radially inward of the plurality of tubes 32 must conduct radially outward to the plurality of tubes 32 resulting in high thermal efficiency. If the plurality of heaters 34 were located radially outward of plurality of tubes 32, then only some of the heat, perhaps only half or less, would travel radially inward to the plurality of tubes 32 whereas the heat that is conducted radially outward in that configuration cannot reach the plurality of tubes 32 and thus cannot heat the process fluid, resulting in poor thermal efficiency. This result of the heaters 34 being radially inward of the tubes 32 is being able to run the heaters 34 at a lower temperature setting due to higher thermal transfer to the tubes 32, which puts less strain on the heaters 34 and surrounding components while reducing power consumption required to obtain desired heating of the process fluid. Putting less energy into the heaters 34 to achieve the same thermal transfer also decreases the heat radiating from fluid heater 10, providing a safer operating environment and reducing risk of combustion.

During operation, electrical power is provided to heaters 34. Heaters 34 generate heat and the heat conducts through the thermally conductive blocks 27. The tubes 32 extend through the thermally conductive blocks 27 and the heat is transferred to the process fluid through the tubes 32. The process fluid is heated as the process fluid flows through the tubes 32 such that the process fluid exiting from fluid heater 10 has an increased temperature relative to the process fluid entering into fluid heater 10. The wet portions of fluid heater 10 are the portions directly exposed to an in contact with the process fluid. The wet portions include manifold assemblies 24 and tubes 32. The blocks 27 do not form the wet portion of fluid heater 10 such that the thermally conductive material of blocks 27 is not directly exposed to the process fluid. The process fluid contacts the material of the manifold assemblies 24 and the material of the tubes 32. In the example shown, the wetted portions of fluid heater 10 are formed by polymer, such as PFA.

Fluid heater 10 provides significant advantages. Tubes 32 are disposed radially between the heaters 34 and the exterior of fluid heater 10 such that the heat radiating radially from heaters 34 flows to the tubes 32 prior to flowing to the exterior of fluid heater 10 to dissipate to atmosphere. Tubes 32 being disposed radially outward of heaters 34 provides efficient heating that reduces power consumption and decreases the power level required to achieve desired temperatures. Blocks 27 are stacked along axis AA. One or more intermediate blocks 27c can be placed between end blocks 27a, 27b to increase an axial length of fluid heater 10. Fluid heaters 34 of greater axial length have greater heating capacity as the residence time of the process fluid within tubes 32 due to the increased axial length of the tubes 32 associated with the greater axial length of core 26.

FIG. 2 is a cross-sectional view of the fluid routing and heating portion of fluid heater 10. Manifold assemblies 24, core 26, and tubes 32 of fluid heater 10 are shown. Core 26 includes blocks 27. Blocks 27 are formed as end blocks 27a, 27b and intermediate blocks 27c. Each manifold assembly 24 includes inner manifold 58 and outer manifold 60.

Core 26 forms a central portion of the fluid routing and heating portion of fluid heater 10. Blocks 27 are formed as thermally conductive components that are stacked axially to form core 26. Blocks 27 do not form wetted portions of fluid heater 10. While the process fluid flows through blocks 27 while flowing within tubes 32, the process fluid is not in contact with the blocks 27.

Heater bores 84 are formed through each block 27 of core 26. The heater bores 84 through each of the blocks 27 are axially aligned relative to each other to form the heater passages 44 that the heaters 34 are disposed within. The heaters 34 extend into each block 27 of the core 26 to heat the thermally conductive material of the blocks 27.

Heater bores 84 are configured to receive and contain the heaters 34. In the example shown, end block 27a and each of intermediate blocks 27c includes heater bores 84 that extend fully axially through the intermediate blocks 27c and end block 27a. The heater bores 84 of end block 27b do not extend fully axially through end block 27b. The portions of the face of end block 27b oriented outward away from intermediate blocks 27c and axially overlapping with the heater passages 44 is closed to the heater passages 44. Material forming end block 27b axially overlaps with the heater passages 44.

In the example shown, end block 27a includes a first bore count of apertures extending fully axially through the end block 27a (formed by heater bores 84, tube bores 84 and fastener bores 86) while end block 27b includes a second bore count of apertures extending fully axially through the end block 27b (formed by tube bores 84 and fastener bores 86. The first bore count is greater than the second bore count. In the example shown, intermediate blocks 27c includes a third bore count of apertures extending fully axially through the intermediate block 27c (formed by heater bores 84, tube bores 84 and fastener bores 86). The first bore count can be the same as the third bore count. The third bore count can be greater than the second bore count. While end block 27b has fewer apertures extending fully axially through end block 27b as compared to end block 27a and intermediate blocks 27c, in the example shown, end block 27b has a greater number of apertures extending into end block 27b than extend into end block 27a or intermediate block 27c as sensor bores 56 are formed in end block 27b but not in end block 27a or intermediate block 27c.

In the example shown, seals 62 are disposed at the interface between each block 27. Seals 62 are disposed at the joint between adjacent blocks 27. Seals 62 are disposed radially between tubes 32, which convey the process fluid through core 26, and the electrical components of fluid heater 10 (e.g., heaters 34 and sensors 36). Seals 62 are radially positioned such that seals 62 inhibit the flow of any process fluid that may have leaked to the electrical components. The seals 62 inhibit flow of the potentially combustible process fluids that may have leaked radially inward towards the heaters 34, which have a higher temperature than at the locations of the tubes 32 and may be at a temperature that can cause combustion of the process fluid. Seal 62 can be formed as a crush seal, among other options. In the example shown, seals 62 are disposed at the mates 54 between adjacent blocks 27. For example, the seals 62 can be disposed in the mate 54 formed as a recess and can be contacted by the mate 54 formed as a projection.

Each manifold assembly 24 is formed from two parts in the example shown. In this example, each manifold assembly 24 is formed from inner manifold 58 and outer manifold 60. The relative directions of inner and outer are relative to the core 26. The inner manifold 58 is disposed axially inward closer to core 26 than outer manifold 60. Each of the inner manifold 58 and the outer manifold 60 are annular in the example shown. Each manifold assembly 24 is formed by axially assembling the outer manifold 60 to the inner manifold 58. Inner manifold 58 and outer manifold 60 are joined at fluid-tight interfaces. In the example shown, inner manifold 58 can be considered to form an inner ring and the outer manifold 60 can be considered to form an outer ring.

The two manifold assemblies 24 can be identical to each other but flipped to mount to core 26 such that both inner manifolds 58 are oriented axially inwards towards the core 26. In some examples, the inlet manifold assembly 24 can be disposed as a mirror image of the outlet manifold assembly 24. In some examples, the inlet manifold assembly 24 can be disposed as a mirror image of the outlet manifold assembly 24 that is rotated about the axis AA. In the example shown, the two manifold assemblies 24 are mirror images but with one manifold rotated 180-degrees relative to the other manifold assembly 24.

Flow chamber 46 is formed between the inner manifold 58 and the outer manifold 60. Flow chamber 46 divides or consolidates the flowing process fluid between one port aperture 48 on outer manifold 60, that fluidly connects with either fluid port 18a, 18b, and multiple fluid apertures 64 on the inner manifold 58 that respectively connect with the plurality of tubes 32. While the outer manifold 60 is shown to include one port aperture 48, in various other embodiments the outer manifold 60 may include a plurality of port apertures 48, however the number of port apertures 48 on the outer manifold 60 is less than the number of fluid apertures 64 on the inner manifold 58. Port apertures 48 and fluid apertures 64 can be considered to form the flow apertures of the manifold assembly 24.

Tubes 32 extend between and fluidly connect the flow chambers 46 of the manifold assemblies 24. Each block 27 includes multiple tube bores 82 that extend axially within the block 27. The tube bores 82 extend fully axially through each block 27. The blocks 27 are aligned about the axis AA such that the tube bores 82 through each block 27 align with the tube bores 82 through the other blocks 27 to form tube passages 42. Tube passages 42 are open on both axial ends of the core 26. Tubes 32 extend through the tube passages 42 to connect with the inner parts 58 of the manifold assemblies 24. It is noted that the plurality of tubes 32 extend through the core 26 so that the process fluid does not touch the blocks 27. The material of the tubes 32 is disposed between the block 27 and the process fluid to isolate the process fluid from the material of the blocks 27. This way, high-purity tubes 32, such as tubes 32 formed from PFA, can be used for contacting the process fluid while the material of the blocks 27 can be selected for heat capacity and conductance without concern of degrading the purity of the process fluid due to contact with the material of the block 27.

In some examples, blocks 27 can be surface treated to add an inhibition layer on the material of the block 27. The inhibition layer is configured to inhibit transference of ions of the metallic material forming blocks 27 to the process fluid flowing within tubes 32. For example, the block 27 can be treated to add a layer of a silicon-based material to block 27. The inhibition layer is disposed at least within the tube bore 82 of each block 27. As such, the inhibition layer is disposed between the tube 32 and the material of the block 27. The inhibition layer can be formed on up to all surfaces of the block 27. For example, the inhibition layer can be formed on the surfaces of tube bores 82, the surfaces of heater bores 84, the axial surfaces of blocks 27, the radially exterior surface of blocks 27, the sensor bores 56, etc. The inhibition layer can be formed as a coating. The inhibition layer can be applied to block 27 by a chemical vapor deposition process.

The process fluid enters into an upstream manifold assembly 24 through the port aperture 48 of that upstream manifold assembly 24. The process fluid flows through the flow chamber 46 of the upstream manifold assembly 24 and enters directly into the tubes 32 from the upstream manifold assembly 24. The process fluid flows through the tubes 32 and exits from tubes 32 directly into the flow chamber 46 of the downstream manifold assembly 24. The process fluid exits from the downstream manifold assembly 24 through the port aperture 48 of the downstream manifold assembly 24.

FIG. 3 is an exploded view of fluid heater 10. FIG. 4 is an exploded view of the fluid handling and heating portion of fluid heater 10. FIGS. 3 and 4 will be discussed together. Fluid heater 10 includes heater housing 12; end caps 14a, 14b; feet 16; fluid ports 18a, 18b; purge ports 20; electrical port 22; manifold assemblies 24; core 26; insulation 28; clamps 30; tubes 32; heaters 34; sensors 36; and core connector 66. Core 26 includes blocks 27.

Heater housing 12 encloses other components of fluid heater 10. End caps 14a, 14b are disposed at the axial ends of heater housing 12. End caps 14a, 14b can be connected to heater housing 12 by multiple fasteners 68. Feet 16 support fluid heater 10 on a surface. In the example shown, feet 16 are connected to end caps 14a, 14b, such as by fasteners 68.

Insulation 28 is disposed around core 26. Insulation 28 is configured to thermally insulate core 26 to retain heat within core 26, providing for more efficient heating of the process fluid flowing through core 26. As shown, insulation 28 is formed in multiple layers that stack radially outward from core 26. In the example shown, the insulation 28 is formed in three sections, with two end sections of insulation 28a that each have at least one layer that radially and axially overlaps with the core 26 and a center section of insulation 28b that wraps around the core 26 to radially overlap with core 26. The center section of insulation 28b does not axially overlap the core 26, in the example shown.

Clamps 30 engage with the exterior of core 26. Clamps 30 are configured to interface with blocks 27 (e.g., end blocks 27a, 27b) and axially retain core 26 within heater housing 12. Each clamp 30 is disposed axially between the center section of insulation 28b and one of end section of insulation 28a. In the example shown, clamps 30 are disposed to axially overlap with one or more layers of the insulation 28.

Core 26 is disposed within heater housing 12. Core 26 is disposed radially inward of heater housing 12 and insulation 28. Core 26 is formed by an axial stack of blocks 27. Heaters 34 are disposed within core 26. Heaters 34 extend within blocks 27. Sensors 36 are supported by core 26. One or more of the sensors 36 can extend within core 26, such as within one or more of the blocks 27.

Blocks 27 are fixed together by core connectors 66. Core connectors 66 extend through each block 27 of core 26. Core connector 66 is configured to secure the stack of blocks 27 axially together. Core connector 66 can be considered to form an axial clamp. In the example shown, core connector 66 includes rods 70 and studs 72. Rods 70 extend axially through the blocks 27. Studs 72 are configured to mount to each axial end of the rods 70. In some examples, the rods 70 can include threaded ends configured to threadedly connect with threading in the studs 72 to fix the axial stack of blocks 27 together.

Manifold assemblies 24 are mounted at the axial ends of core 26. The example shown includes a first manifold assembly 24 on one axial end of core 26 and a second manifold assembly 24 at a second axial end of core 26. The inner manifold 58 of the manifold assembly 24 is disposed adjacent to core 26. The outer manifold 60 of the manifold assembly 24 is connected to inner manifold 58. Each fluid port 18a, 18b is interfaces with an outer manifold 60 of a manifold assembly 24 for fluid communication with that manifold assembly 24. Manifold assemblies 24, including the inner manifold 58 and the outer manifold 60, can be formed from polymer, such as a type previously mentioned. As previously discussed, this can avoid metal contact with the process fluid to maintain its purity. It is noted that the process fluid can flow entirely through the fluid heater 10 without contacting the metallic components. Contact between the solvent and metal and various other types of materials should be avoided to avoid the solvent from reacting with such material and generating impurities.

Leak sensor 37 is disposed proximate fluid port 18a. Sensor housing 39 houses the sensing component of leak sensor 37. For example, sensor housing 39 can house a fiber optic sensing component of leak sensor 37. Sensor housing 39 can protect the fiber optic sensor’s light diffusion tip from contacting the insulation 28 and can position the sensing component for sensing leaks of the process fluid.

Tubes 32 extend axially through core 26. Each tube 32 can have an axial length greater than the axial length of the core 26. The longer tubes 32 can project axially out of each end of core 26 to interface with the inner manifolds 58 of each manifold assembly 24. Tubes 32 interface with manifold assemblies 24 such that the process fluid does not directly contact the blocks 27. The process fluid flows through core 26 but does not directly contact core 26. Instead, the process fluid flows within and contacts tubes 32 that extend within and through core 26.

FIG. 5 is an enlarged cross-sectional, isometric view of showing a portion of fluid heater 10. Manifold assembly 24, core 26, fluid port 18b, heater 34, sensors 36, clamp 30, and insulation 28 are shown. Manifold assembly 24 includes inner manifold 8 and outer manifold 60. End block 27b and a portion of an intermediate block 27c of core 26 are shown.

Manifold assembly 24 is mounted to core 26. Inner manifold 58 interfaces with core 26 in the example shown. Fluid port 18a is fluidly connected to manifold assembly 24. Outer manifold 60 interfaces with fluid port 18a in the example shown. Outer manifold 60 is connected to inner manifold 58 to form the manifold assembly 24.

Flow chamber 46 is formed within manifold assembly 24 between inner manifold 58 and outer manifold 60. Inner manifold 58 and outer manifold 60 are connected together to define the flow chamber 46. In the example shown, inner manifold 58 and outer manifold 60 interface at inner connection 74 and outer connection 76. The inner connection 74 is formed by a tongue-in-groove interface. In the example shown, the outer manifold 60 includes a projection that extends into a slot formed in the inner manifold 58. The projection and slot can both extend fully annularly about the axis AA. The inner manifold 58 and outer manifold 60 can be mechanically fused at the inner connection 74. For example, each of inner manifold 58 and outer manifold 60 can be formed from the same or similar fluid conveying material as tubes 32 (e.g., polymer such as PFA). For example, at least the fluid-contacting portions of inner manifold 58 and outer manifold 60 can be formed from PFA, among other options. The mechanical fusion can be formed by melting the material of inner manifold 58 and outer manifold 60 together at inner connection 74. The outer connection 76 can be an abutment interface. The inner manifold 58 and outer manifold 60 can be mechanically fused at outer connection 76, such as by welding, among other fixation options.

Multiple fluid apertures 64 are formed through inner manifold 58. Each fluid aperture 64 is associated with a single tube 32 of the plurality of tubes 32. The fluid apertures 64 provide passages for the process fluid to enter into the tubes 32 or exit from the tubes 32. The fluid apertures 64 provide passages for the tubes 32 to extend into.

Recess 52 is formed in end block 27b. The recess 52 extends into the axial end face of end block 27b. Sensor bores 56 open to recess 52. As shown, potting material 78 is disposed within the recess 52 to help secure and seal electrical connections with, in this case, sensors 36, or heaters 34 on the opposite end of fluid heater 10.

The interface between end block 27b and an intermediate block 27c is shown in FIG. 5. Mate 54b on end block 27b is formed as a projection. Mate 54a on intermediate block 27c is formed as a recess. The projection forming the mate 54b of end block 27b extends into the recess 52 forming the mate 54a of intermediate block 27c to position and align the blocks 27 relative to each other.

In the example shown, end block 27b includes flange 80 that projects from the exterior surface of end block 27b. Flange 80 extends radially outward away from axis AA. Flange 80 is configured to interface with clamp 30 and provides a location for clamp 30 to engage with core 26. The flange 80 can be formed as an annular ring extending fully about the exterior of end block 27a. It is understood, however, that flange 80 can be formed in any desired configuration for interfacing with clamp 30. For example, the flange 80 can be formed as a series of discrete projections, a single projection, an array of arcuate projections, etc. Clamp 30 engages with flange 80 and heater housing 12 and axially positions core 26 within heater housing 12.

Fastener bores 86 extend through blocks 27. Fastener bores 86 through each block 27 align with fastener bores 86 of other ones of the blocks 27 to form fastener passages that extend through core 26. The rods 70 of core connector 66 extend though the aligned fastener bores 86 to clamp the blocks 27 axially together to form core 26.

FIG. 6 A is a first isometric view of inner manifold 58. FIG. 6B is a second isometric view of inner manifold 58. FIGS. 6A and 6B will be discussed together. Inner manifold 58 includes fluid apertures 64, ring body 88, inner face 90, outer face 92, inner step 94a, outer step 96a, bosses 98, inner disk 100, and disk apertures 102.

Inner manifold 58 is configured to form a part of manifold assembly 24. Inner manifold 58 at least partially defines flow chamber 46. Inner manifold 58 can interface with a block 27 (e.g., one of end blocks 27a, 27b) to mount manifold assembly 24 to the core 26.

Ring body 88 forms a main body of inner manifold 58. Ring body 88 is configured to extend about axis AA with inner manifold 58 assembled to fluid heater 10. Inner disk 100 is disposed radially within ring body 88. Inner disk 100 is configured to be removed from inner manifold 58 prior to inner manifold 58 being assembled to fluid heater 10. Disk apertures 102 extend through inner disk 100. Disk apertures 102 provide locations for aligning inner manifold 58 during manufacturing. The inner disk 100 can be removed to facilitate installation of heaters 34 and/or sensors 36 through inner manifold 58 mount aperture 104 of inner manifold 58. Mount aperture 104 is a central aperture through inner manifold 58 formed by removal of inner disk 100. Heaters 34 and/or sensors 36 can be installed through mount aperture 104 and wires of the electrical components can pass through mount aperture 104.

Ring body 88 is configured to interface with outer manifold 60 to form manifold assembly 24 and is configured to interface with a block 27 (e.g., an end block 27a, 27b) to mount manifold assembly 24 on core 26. Inner face 90 forms an axial face of inner manifold 58 oriented axially inwards towards core 26.

Receiving bore 106 extends into inner side 110. Receiving bore 106 is an opening that a portion of the core connector 66 can extend into with manifold assembly 24 mounted on core 26. For example, the rod 70 and/or stud 72 of the core connector 66 can extend into receiving bore 106 to be at least partially disposed within receiving bore 106. Receiving bore 106 does not extend fully axially through inner manifold 58 in the example shown.

Outer face 92 forms an axial face of inner manifold 58 oriented axially outwards away from core 26. Outer face 92 is oriented axially towards outer manifold 60. Outer face 92 at least partially defines the flow chamber 46. Outer face 92 is at least partially exposed to the process fluid flowing within flow chamber 46.

In the example shown, bosses 98 are formed on outer face 92. Bosses 98 project axially relative to the base surface forming outer face 92. Bosses 98 project axially away from that base surface. Bosses 98 are configured to project into the flow chamber 46 relative to that base surface. In the example shown, multiple bosses 98 are formed on outer face 92. In the example shown, inner manifold 58 includes two arcuate bosses 98 that are each curved partially about the axis AA. It is understood, however, that inner manifold 58 can include as many or as few bosses 98 as desired, such as zero, one, two, three, four, or more.

Fluid apertures 64 extend fully axially through inner manifold 58. In the example shown, each fluid aperture 64 includes a first opening formed on inner face 90 and a second opening formed on outer face 92. In the example shown, each second opening is formed in a boss 98 such that each second opening is spaced axially outward from the base surface of outer face 92.

Each fluid aperture 64 is configured to receive a single one of the tubes 32 that extend through core 26. The tube 32 can project fully axially through the fluid aperture 64. In some examples, the tube 32 projects to the second opening formed on outer face 92.

As shown, the plurality of fluid apertures 64 are arrayed about the axis AA. The array is circular about the axis, however in this embodiment, a complete circle is not formed from the array of tubes 32, but rather multiple semicircular parts are formed from an array. Fluid apertures 64 and tubes 32 can be considered to be disposed in multiple subarrays in the example shown. In the example shown, the fluid apertures 64, and thus tubes 32, are disposed in first and second circumferential subarrays that are disposed arcuately about the axis AA. Each circumferential subarray of fluid apertures 64 is associated with a single boss 98 in such an example. The circumferential subarrays each extend partially about the axis AA. In the example shown, the fluid apertures 64, and thus tubes 32, are disposed in first and second radial subarrays. The radial subarrays are disposed at different radial distances from the axis AA. In the example shown, the fluid apertures 64, and thus tubes 32, of the first radial subarray are radially offset from the fluid apertures 64, and thus tubes 32, of the second radial subarray. Stacking the fluid apertures 64 and tubes 32 in radial arrays provides for a compact configuration of fluid heater 10 and provides for efficient heating of the process fluid.

The tubes 32 can be fixed to the inner manifold 58. Tubes 32 can be fixed to the inner manifold 58 to provide a unitary assembly that inhibits leakage of any process fluid between the tubes 32 and the inner manifold 58. For example, tubes 32 can be fused to the inner manifold 58. For example, the tubes 32 can be fused to the inner manifold 58 by melting of the PFA material of the tube 32 and melting of the PFA material of the inner manifold 58 at the interface to fuse the tubes 32 and inner manifold 58 together.

Inner step 94a is formed on outer face 92 of inner manifold 58. Inner step 94a is configured to interface with inner step 94b of outer manifold 60 with inner manifold 58 and outer manifold 60 mounted together. Inner step 94a is disposed radially between the axis AA and the fluid apertures 64. Inner step 94a is formed as an annular groove in the example shown. Inner step 94a extends fully circumferentially about the axis AA in the example shown. Inner step 94a extends into outer face 92 and towards inner face 90. Inner step 94a does not extend fully axially through the inner manifold 58.

Outer step 96a is formed on outer face 92 of inner manifold 58. Outer step 96a is configured to interface with outer step 96b of outer manifold 60 with inner manifold 58 and outer manifold 60 mounted together. Outer step 96a is disposed radially between the fluid apertures 64 and the outer edge 108 of inner manifold 58. Outer step 96a is disposed radially outward of inner step 94a. The fluid apertures 64 are disposed radially between the inner step 94a and the outer step 96a. Outer step 96a is formed as an annular surface oriented axially away from core 26. Outer step 96a extends fully circumferentially about the axis AA in the example shown. Outer step 96a can be a planar surface disposed in a plane normal to axis AA in some examples. FIG. 7 A is an isometric view of outer manifold 60. FIG. 7B is a second isometric view of outer manifold 60. FIGS. 7A and 7B will be discussed together. Outer manifold 60 includes port aperture 48, inner step 94b, outer step 96b, inner side 110, outer side 112, flow groove 114, and central aperture 116.

Outer manifold 60 is configured to interface with inner manifold 58 to form a manifold assembly 24. Inner side 110 of outer manifold 60 is configured to be oriented axially inwards towards the core 26. Outer side of outer manifold 60 is configured to be oriented axially outwards away from the core 26.

Inner side 110 is at least partially exposed to the process fluid flowing through manifold assembly 24. Inner side 110 at least partially defines the flow chamber 46 through manifold assembly 24. Flow groove 114 is formed on inner side 110. Flow groove 114 is oriented axially inwards towards core 26. Flow groove 114 formed as an annular groove that extends fully annularly about the axis AA. Flow groove 114 is open axially inwards towards core 26. In the example shown, flow groove 114 is uninterrupted such that the flow chamber 46 is an uninterrupted chamber extending fully annularly about axis AA. Flow groove 114 is oriented such that a base of the flow groove 114 is disposed further axially away from inner manifold 58 than the inner connection 74 between inner manifold 58 and outer manifold 60 and such that the base of flow groove 114 is disposed further axially away from inner manifold 58 than the outer connection 76 between inner manifold 58 and outer manifold 60. In the example shown, flow groove 114 is formed as a U-shaped groove, though it is understood that other configurations are possible. In some examples, the base of the flow groove 114 can be formed as a flat surface in a plane normal to the axis AA.

Port aperture 48 is formed through outer manifold 60. Port aperture 48 extends between inner side 110 and outer side 112. Port aperture 48 is formed through a base of flow groove 114 in the example shown. Port aperture 48 provides a location for process fluid to enter into (in an upstream manifold assembly 24) or exit from (in a downstream manifold assembly 24) the flow groove 114. The port aperture 48 can include dual diameters on the interior of port aperture 48. The dual diameters can facilitate the fitting 38a, 38b of a fluid port 18a, 18b extending into the larger diameter portion (extending into port aperture 48 from outer side 112) to mate the fitting 38 a, 38b with outer manifold 60 while the smaller diameter portion (extending from inner side 110) limits the distance that the fluid port 18a, 18b can extend into port aperture 48. In some examples, a seal can be disposed within port aperture 48 between the exterior of the fluid port 18a, 18b and the surface defining port aperture 48. Central aperture 116 is formed through outer manifold 60. Central aperture 116 provides an opening through which heaters 34 and/or sensors 36 can be accessed for installation, replacement, servicing, etc. Central aperture 116 facilitates servicing and assembly of fluid heater 10. The wires of the electrical components can extend through central aperture 116.

Inner step 94b is formed on inner side 110 of outer manifold 60. Inner step 94b is configured to interface with inner step 94a of inner manifold 58 with inner manifold 58 and outer manifold 60 mounted together. Inner step 94b is disposed radially between the axis AA and the port aperture 48. Inner step 94b is formed as an annular projection in the example shown. Inner step 94b can be considered to form an axially extending flange. Inner step 94b extends fully circumferentially about the axis AA in the example shown. Inner step 94b extends axially away from inner side 110. Inner step 94b is configured to extend into the groove forming inner step 94a in the example shown. It is understood, however, that inner step 94b can be formed as a groove extending into inner face 90 and inner step 94a can be formed as a projection configured to extend into the groove of inner step 94b.

Outer step 96b is formed on inner face 90 of outer manifold 60. Outer step 96b is configured to interface with outer step 96a of inner manifold 58 with inner manifold 58 and outer manifold 60 mounted together. Outer step 96b is disposed radially between port aperture 48 and the outer edge 108b of outer manifold 60. Outer step 96b is disposed radially outward of inner step 94a. The port aperture 48 is disposed radially between the inner step 94b and the outer step 96b. Outer step 96b is formed as an annular surface oriented axially towards core 26. Outer step 96b extends fully circumferentially about the axis AA in the example shown. Outer step 96b can be formed as a planar surface disposed in a plane normal to the axis AA.

FIG. 8 A is an isometric view of end block 27a. FIG. 8B is an isometric view of end block 27b. FIGS. 8A and 8B will be discussed together. The tube bores 82, heater bores 84, fastener bores 86, block body 122, block face 124a, and block face 124b of each end block 27a, 27b are shown. End block 27a includes a mate 54a. End block 27b includes a mate 54b.

End blocks 27a, 27b are configured as the axial-most blocks 27 of the core 26 of a fluid heater 10. The end blocks 27a, 27b can be directly mated together to from a core 26 having a minimum length. Intermediate blocks 27c can be mounted between end blocks 27a, 27b to form cores 26 having greater axial lengths.

Block faces 124a of the end blocks 27a, 27b are configured to be oriented axially outward relative to core 26. The block face 124a of end block 27a is configured to be oriented away from the block face 124a of end block 27b. Similarly, the block face 124a of end block 27b is configured to be oriented away from the block face 124a of end block 27a. Block faces 124b of end blocks 27 a, 27b are configured to be oriented axially inwards towards each other. Block faces 124a are oriented axially away from intermediate blocks 27c in examples in which intermediate blocks 27c are present. Block faces 124b are oriented axially inward towards intermediate blocks 27c in examples in which intermediate blocks 27c are not present.

Tube bores 82 extend fully axially through each end block 27a, 27b. Projections 118 extend axially outward from block face 124a. The tube bores 82 are formed through the projections 118 in the example shown. The end blocks 27a, 27b can include the same number of projections 118 as tube bores 82. Projections 118 are configured to interface with inner manifold 58 with manifold assembly 24 mounted to end block 27a, 27b. In the example shown, the projections 118 are configured to extend into the fluid apertures 64 of the inner manifold 58 to be disposed at least partially within the fluid apertures 64. The projections 118 extend into the fluid aperture 64 through the openings on the inner face 90 of inner manifold 58. Tubes 32 project out of the projections 118 and into the fluid apertures 64 to mate with inner manifold 58. Projections 118 extending into inner manifolds 58 minimizes the length of tubes 32 that is not disposed within and supported by the material forming the blocks 27. Projections 118 can be formed as cylindrical projections, among other options.

Heater bores 84 are formed within end blocks 27a, 27b. In the example shown, heater bores 84 of end block 27b do not extend fully axially through that end block 27b. In the example shown, heater bores 84 of end block 27a do extend fully axially through that end block 27a such that heaters 34 can pass fully through the heater bores 84 of end block 27a such that heaters 34 extend fully axially through end block 27a. The heater bores 84 of end block 27b are closed such that heaters 34terminate within the heater bores 84 of end block 27b.

Fastener bores 86 extend fully axially through the end blocks 27a, 27b. The fastener bores 86 provide openings for core connector 66 to extend through blocks 27 to axially clamp the blocks 27 together to form core 26. In the example shown, each end block 27a, 27b includes multiple fastener bores 86. The fastener bores 86 are disposed 180-degrees apart in the example shown.

Flanges 80 project radially outward from the radially exterior surface of the end blocks 27a, 27b. The flanges 80 are configured to interface with a clamp 30 to provide a location for the clamp 30 to engage with core 26.

Intermediate blocks 27c (FIGS. 2B-5) can be configured similar to end blocks 27a, 27b, except that a first axial face of the intermediate block 27c is configured as the block face 124b of end block 27a (including the mate 54a) while a second axial face of the intermediate block 27c is configured as the block face 124b of end block 27b (including the mate 54b). Additionally, intermediate blocks 27c do not include flanges 80 in the example shown. The first axial face of the intermediate block 27c can interface with block face 124b of end block 27b or with a second axial face of an adjacent intermediate block 27c. The second axial face of the intermediate block 27c can interface with the block face 124b of end block 27 a or with a first axial face of an adjacent intermediate block 27c. Heater bores 84 and tube bores 82 of the intermediate blocks 27c extend fully axially through the intermediate blocks 27c.

FIG. 9 is a cross-sectional isometric view of a fluid heater 10' having a reduced length relative to fluid heater 10. Fluid heater 10' is substantively similar to fluid heater 10 (best seen in FIGS. 1A, IB, 3, and 4) except that fluid heater 10' has a shorter axial length that fluid heater 10.

The core 26 of fluid heater 10' is formed from end blocks 27a, 27b mounted adjacent to each other to directly interface with each other. Fluid heater 10' does not include intermediate blocks 27c axially between end blocks 27a, 27b. Fluid heater 10' has a shorter axial length than fluid heater 10, reducing the residency time and heat transfer to the process fluid when heated by fluid heater 10’.

FIG. 10 is an isometric view of a fluid heater 10" having an increased length relative to fluid heater 10 and fluid heater 10'.

The core 26 of fluid heater 10" is formed from end blocks 27a, 27b with multiple intermediate blocks 27c disposed therebetween. Fluid heater 10" includes a greater number of intermediate blocks 27c than fluid heater 10, providing a fluid heater having an increased axial length. Fluid heater 10" has a larger axial length than fluid heater 10, increasing the residency time and heat transfer to the process fluid when heated by fluid heater 10".

As best seen in FIGS. IB, 9, and 10, fluid heater 10, fluid heater 10', and fluid heater 10" have similarly configured components such that the blocks 27 can be utilized to form cores 26 having different axial lengths, thereby providing fluid heaters having any desired length. The intermediate blocks 27c are configured similar to each other such that any desired number, zero, one, two, three, four, or more, of intermediate blocks 27c can be fit between the end blocks 27a, 27b to set the axial length of the core 26. Some examples includes twelve or more intermediate blocks 27c. The axial length of the fluid heater can be changed by adding or removing intermediate blocks 27c to change an axial length of the core 26. Generally, the longer the core 26, the greater the surface area along a plurality of tubes 32 for delivering heat to the process fluid and the larger (e.g., longer) a heater 34 that can be installed to generate more thermal energy for heating of the process fluid. Thus, longer cores 26 can be associated with greater heating capacity.

While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment(s) disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

CLAIMS:

1. A fluid heater configured to increase a temperature of a process fluid, the fluid heater comprising: a heater housing elongate along an axis between a first housing end and a second housing end; a first manifold assembly disposed within the heater housing and in fluid communication with a fluid inlet of the fluid heater; a second manifold assembly disposed within the heater housing and in fluid communication with a fluid outlet of the fluid heater; a plurality of tubes extending within the heater housing between the first manifold assembly and the second manifold assembly to fluidly connect the first manifold assembly and the second manifold assembly; and at least one heater located within the heater housing, wherein the plurality of tubes are arrayed radially outward of the at least one heater.

2. The fluid heater of claim 1, wherein the plurality of tubes extend at least partially circumferentially around the at least one heater.

3. The fluid heater of any one of claims 1 and 2, wherein the at least one heater is disposed axially between the first manifold assembly and the second manifold assembly.

4. The fluid heater of claim 3, wherein the at least one heater does not radially overlap with either of the first manifold assembly and the second manifold assembly.

5. The fluid heater of any preceding claim, wherein the plurality of tubes are arrayed in one of a semi-circular array and a circular array about the axis.

6. The fluid heater of any preceding claim, wherein one or both of the first manifold assembly and the second manifold assembly are formed, respectively, from at least one ring.

7. The fluid heater of claim 6, wherein one or both of the first manifold assembly and the second manifold assembly are formed, respectively, from an inner manifold and an outer manifold that axially assemble to form an annular flow chamber located between the inner manifold and the outer manifold, and wherein at least one of the inner manifold and the outer manifold form the at least one ring.

8. The fluid heater of claim 7, wherein the inner manifold interfaces with the outer manifold at an inner connection and an outer connection, the outer connection disposed radially outward from the inner connection.

9. The fluid heater of claim 8, wherein the inner connection is formed by a projection of one of the inner manifold and the outer manifold extending into a groove of the other one of the inner manifold and the outer manifold.

10. The fluid heater of any one of claims 8 and 9, wherein the outer connection is formed at an abutment interface between the inner manifold and the outer manifold.

11. The fluid heater of any one of claims 6-10, further comprising one or more electrical components extending through the at least one ring.

12. The fluid heater of claim 11, wherein the one or more electrical components include at least one of heater wiring connected to the at least one heater and sensor wiring connected to at least one sensor.

13. The fluid heater of any one of claims 1-5, wherein the first manifold assembly includes a first inner manifold connected to the plurality of tubes and a first outer manifold opposing the first inner manifold, the first inner manifold and the first outer manifold defining a first flow chamber in fluid communication with the plurality of tubes.

14. The fluid heater of claim 13, wherein a first fluid port is connected to the first outer manifold, the first fluid port forming the fluid inlet.

15. The fluid heater of any one of claims 13 and 14, wherein the first inner manifold includes a plurality of fluid apertures extending fully axially therethrough, and wherein each tube of the plurality of tubes extend into a respective fluid aperture of the plurality of fluid apertures.

16. The fluid heater of claim 15, wherein the plurality of fluid apertures are disposed in a first arcuate array extending partially around the axis and a second arcuate array extending partially around the axis.

17. The fluid heater of claim 16, wherein the first arcuate array is spaced circumferentially from the second arcuate array.

18. The fluid heater of claim 16, wherein the first arcuate array is disposed radially outward from the second arcuate array.

19. The fluid heater of claim 15, wherein the plurality of fluid apertures includes a first subset of fluid apertures disposed radially inward from a second subset of fluid apertures.

20. The fluid heater of claim 13, wherein the first outer manifold includes a first count of flow apertures through which process fluid is configured to flow, the first inner manifold includes a second count of flow apertures through which the process fluid is configured to flow, and the second count is greater than the first count.

21. The fluid heater of claim 20, wherein the first count is one and the second count is at least twenty.

22. The fluid heater of claim 21, wherein the second count is at least sixty.

23. The fluid heater of any preceding claim, further comprising: a core extending axially within the heater housing, wherein the plurality of tubes and the at least one heater are disposed within the core.

24. The fluid heater of claim 23, wherein the core is formed from metal that conducts heat from the at least one heater to the plurality of tubes.

25. The fluid heater of claim 24, wherein the core is formed from a plurality of blocks stacked axially, and wherein the plurality of tubes extend through the plurality of blocks.

26. The fluid heater of claim 25, wherein the plurality of blocks include a plurality of mates that interface axially.

27. The fluid heater of claim 26, wherein the plurality of mates comprise annular projections received within annular recesses.

28. The fluid heater of any one of claims 25-27, wherein the plurality of blocks includes a first end block forming a portion of the core axially closest to the first manifold assembly and a second end block forming a portion of the core axially closest to the second manifold assembly.

29. The fluid heater of claim 28, wherein the plurality of blocks further includes at least one intermediate block disposed axially between the first end block and the second end block.

30. The fluid heater of claim 29, wherein the at least one intermediate block includes a plurality of intermediate blocks.

31. The fluid heater of any one of claims 28-30, wherein the first manifold assembly is mounted to the first end block and the second manifold assembly is mounted to the second end block.

32. The fluid heater of any of claims 24-31, wherein the core is formed from aluminum.

33. The fluid heater of any preceding claim, further comprising a plurality of temperature sensors located within the heater housing.

34. The fluid heater of claim 33, wherein the at least one heater is wired through one of the first manifold assembly and the second manifold assembly, and the plurality of temperature sensors are wired through the other one of the first manifold assembly and the second manifold assembly.

35. The fluid heater of any preceding claim, wherein the heater housing is cylindrical.

36. The fluid heater of any preceding claim, wherein a purge pathway is formed within the heater housing, the purge pathway at least partially disposed radially outward of the plurality of tubes.

37. A fluid heater configured to increase a temperature of a process fluid, the fluid heater comprising: a heater housing elongate along an axis between a first housing end and a second housing end; a first manifold assembly disposed within the heater housing and in fluid communication with a fluid inlet; a second manifold assembly disposed within the heater housing and in fluid communication with a fluid outlet; a core disposed within the heater housing axially between the first manifold assembly and the second manifold assembly, wherein the core is formed from a plurality of blocks stacked axially, the plurality of blocks being thermally conductive; a plurality of tubes extending through the core between the first manifold assembly and the second manifold assembly to fluidly connect the first manifold assembly and the second manifold assembly; and at least one heater located within the core radially inward of the plurality of tubes.

38. The fluid heater of claim 37, wherein the plurality of blocks are formed from a metal and the plurality of tubes are formed from a plastic.

39. The fluid heater of claim 38, wherein the plurality of tubes are formed from perfluoroalkoxy (PF A).

40. The fluid heater of any one of claims 38 and 39, wherein the plurality of blocks are formed from aluminum.

41. The fluid heater of any one of claims 37-40, wherein the plurality of blocks includes: a first end block forming a portion of the core axially closest to the first manifold assembly; and a second end block forming a portion of the core axially closest to the second manifold assembly.

42. The fluid heater of claim 41 , wherein the first end block is configured differently from the second end block.

43. The fluid heater of any one of claims 41 and 42, wherein the plurality of blocks includes at least one intermediate block disposed axially between the first end block and the second end block.

44. The fluid heater of claim 43, wherein the at least one intermediate block is configured differently than the first end block and the second end block.

45. The fluid heater of any one of claims 43 and 44, wherein the at least one intermediate block includes a plurality of intermediate blocks.

46. The fluid heater of claim 45, wherein each intermediate block of the plurality of intermediate blocks is configured identically.

47. The fluid heater of claim 41 , wherein: the first end block includes a first bore count of apertures extending fully axially the first end block; the second end block includes a second bore count of apertures extending fully axially through the second end block; and the first bore count is greater than the second bore count.

48. The fluid heater of claim 47, wherein the plurality of blocks includes at least one intermediate block disposed axially between the first end block and the second end block; the at least one intermediate block includes a third bore count of apertures extending fully axially through the at least one intermediate block; and the third bore count is greater than the second bore count.

49. The fluid heater of claim 48, wherein the first bore count is the same as the third bore count.

50. The fluid heater of any one of claims 47-49, wherein: the core defines at least one heater passage within which the at least one heater is disposed, the at least one heater passage formed by a plurality of aligned heater bores formed within the plurality of blocks; and a heater bore of the second end block does not extend fully axially through the first end block.

51. The fluid heater of any one of claims 37-50, the core comprising: a plurality of tube passages extending fully axially through each of the plurality of blocks, the plurality of tubes disposed at least partially within the plurality of tube passages.

52. The fluid heater of claim 51, wherein the plurality of tubes extend fully axially through the plurality of tube passages to interface with the first manifold assembly and the second manifold assembly.

53. The fluid heater of any one of claims 51-52, wherein a fluid pathway through the fluid heater extends downstream from the fluid inlet to the first manifold assembly, from the first manifold assembly through the plurality of tubes, from the plurality of tubes to the second manifold assembly, and from second to the fluid outlet such that the process fluid does not contact the plurality of blocks.

54. The fluid heater of claim 53, further comprising an inhibition layer disposed between tubes of the plurality of tubes and respective tube passages of the plurality of tube passages.

55. The fluid heater of claim 54, wherein the inhibition layer is formed as a coating on the plurality of blocks.

56. The fluid heater of any one of claims 54 and 55, wherein the inhibition layer includes silicon.

57. The fluid heater of any one of claims 37-56, wherein, extending radially outward from the axis are, in order, the heaters, then the tubes, then a radial exterior the plurality of blocks, then the heater housing.

58. The fluid heater of claim 57, further comprising insulation disposed radially between the radial exterior of the plurality of blocks and the heater housing.

59. The fluid heater of claim 58, wherein the insulation is formed by a plurality of insulating sheets stacked together.

60. The fluid heater of claim 57, wherein a purge pathway for a purge gas is disposed radially between the radial exterior of the plurality of blocks and the heater housing.

61. The fluid heater of claim 60, wherein the purge pathway is disposed radially between insulation and the heater housing.

62. A fluid heater configured to increase a temperature of a process fluid, the fluid heater comprising: a heater housing elongate along an axis between a first housing end and a second housing end; a first manifold assembly disposed within the heater housing and in fluid communication with a first fluid port formed by one of a fluid inlet and a fluid outlet, the first manifold assembly comprising: a first inner manifold having a first plurality of fluid apertures extending therethrough; a first outer manifold having a first port aperture extending therethrough, the first outer manifold in fluid communication with the first fluid port through the first port aperture; and a first flow chamber formed between the first inner manifold and the first outer manifold, the first flow chamber providing fluid communication between the first port aperture and the first plurality of fluid apertures; a second manifold assembly disposed within the heater housing and in fluid communication with a second fluid port formed by the other one of the fluid inlet and the fluid outlet; a core disposed within the heater housing axially between the first manifold assembly and the second manifold assembly; a plurality of tubes extending through the core between the first plurality of fluid apertures and the second manifold assembly to fluidly connect the first flow chamber and the second manifold assembly; and at least one heater located within the core radially inward of the plurality of tubes.

63. The fluid heater of claim 62, wherein the at least one heater is disposed radially inward of the first flow chamber.

64. The fluid heater of any one of claims 62 and 63, wherein the first inner manifold includes a first inner step and a first outer step, the first plurality of fluid apertures disposed radially between the first inner step and the first outer step.

65. The fluid heater of claim 64, wherein the first inner step includes an annular groove.

66. The fluid heater of claim 65 , wherein the outer manifold includes a second inner step configured to interface with the first inner step and a second outer step configured to interface with the first outer step.

67. The fluid heater of claim 66, wherein the second inner step includes an annular projection configured to extend into the annular groove.

68. The fluid heater of any one of claims 66 and 67, wherein the first outer step abuts the second outer step.

69. The fluid heater of claim 68, wherein the first outer step does not extend axially into the second outer step.

70. The fluid heater of any one of claims 62-69, wherein the first outer manifold includes a flow groove extending into an axial face of the first outer ring oriented towards the first inner manifold such that a base of the flow groove is disposed further from the inner manifold than an interface between the inner manifold and the outer manifold.

71. The fluid heater of claim 70, wherein the flow groove is a U-shaped groove.

72. The fluid heater of any one of claims 62-71, the first inner manifold including: an outer face exposed to the flow chamber; and at least one boss projecting from the outer face towards the outer manifold; wherein openings of the plurality of fluid apertures are formed through the at least one boss.

73. The fluid heater of claim 72, wherein the at least one boss extends at least partially around the axis.

74. The fluid heater of any one of claims 72 and 73, wherein the at least one boss includes a plurality of bosses.

75. The fluid heater of claim 74, wherein each boss of the plurality of bosses extends arcuately around the axis.

76. The fluid heater of any one of claims 62-75, wherein the plurality of tubes extend into the first plurality of fluid apertures.

77. The fluid heater of claim 76, wherein the plurality of tubes are fused to the first inner manifold.

78. The fluid heater of claim 77, wherein the plurality of tubes are formed from perfluoroalkoxy (PF A) and the first inner manifold is at least partially formed from PFA.

79. The fluid heater of any one of claims 62-78, the second manifold assembly comprising: a second inner manifold having a second plurality of fluid apertures extending therethrough; a second outer manifold having a second port aperture extending therethrough, the second outer manifold in fluid communication with the second fluid port through the second port aperture; and a second flow chamber formed between the second inner manifold and the second outer manifold, the second flow chamber providing fluid communication between the second port aperture and the second plurality of fluid apertures.

80. The fluid heater of claim 79, wherein the second manifold assembly is identical to the first manifold assembly and flipped relative to the first manifold assembly so both the first inner manifold and the second inner manifold are oriented axially inwards towards the core.

81. The fluid heater of claim 79, wherein the first inner manifold is disposed as a mirror image of the second inner manifold.

82. The fluid heater of claim 79, wherein the first outer manifold is disposed as a mirror image of the second outer manifold that is rotated about the axis.