DE3125933A1 - Heat exchanger - Google Patents

Abstract

The heat exchanger has doubled sealing elements through which a circulation fluid circulates. The circulation fluid can be used to determine leaks, for the purpose of cooling, or for sterilisation or other purposes. The heat exchanger contains a multiplicity of coaxially arranged tubes (4) made from thermally conductive material, which are held at a spacing in the radial direction by a pair of final distributors (2), in order to form annular passages for fluid flow. At least one of the distributors (2) has first and second sealing elements (25) for forming seals between the distributor (2) and the ends of the tubes (4). In this case, fluid passages (30) extending along a circumference are formed between the first and second sealing elements (25). The final distributor (2) further has circulation fluid inlets (32, 18, 34) for feeding a circulation fluid to first points in the passages (30), as well as circulation fluid outlets (36, 19, 38) for discharging the circulation fluid at second points in the passages (30). The first and second points for each passage (30) are arranged offset from one another over a circumference. <IMAGE>

Description

The invention relates to a heat exchanger as particularly, but not exclusively, described in US Pat. No. 4,146,088 is. This US patent describes a heat exchanger which includes a plurality of concentric tubes clamped between end manifolds. The liquid flow passages for the heat exchanger are formed in the annular areas between adjacent tubes. The end manifolds contain O-rings that sealingly engage the inner surfaces of the ends of the tubes.

The invention relates to an improvement in such heat exchangers which are used to advantage in various ways can. Basically, the invention provides devices for bringing about a cleaning fluid flow in the area between the O-ring or rings and the ends of the tubes.

Such a cleaning flow can on the one hand work as a coolant for cooling the O-rings and thereby make the exchanger better for treating fluids at higher temperatures.

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make temperatures suitable. Second, the cleaning fluid can be maintained at a pressure that is greater as the pressure of the fluids flowing in the annular fluid paths between adjacent fluids, if a leak occurs between the O-rings and the ends of the tubes, the cleaning fluid flows into these annular spaces so that mixing of the treated Fluids in the heat exchanger does not occur.

According to a third mode of use, the cleaning fluid can be maintained at a relatively low pressure and an over Monitoring system can be provided to detect the presence of one or both heat exchange fluids in the cleaning fluid can. So if one or the other other of the heat exchange fluids is detected, is it a sign of a broken or damaged O-ring. It is also possible for the cleaning fluid to sterilize the passage between the O-rings, thereby removing biological contamination in the event of a damaged seal.

According to the invention is a heat exchanger for fluids with

a plurality of coaxially arranged tubes of thermally conductive material are provided, the tubes in radial Direction spaced apart by a pair of end manifolds to form annular fluid passages will hold and at least one of the manifolds first and second sealing elements to form seals therebetween the manifold and the ends of the tubes, along a circumference extending fluid passages formed between the first and second sealing elements, a circular tion fluid inlet for supplying a circulation

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fluid at first points in the passages and circulation fluid outlets for outlet of the circulating fluid at second locations in the passages, wherein the first and second locations are circumferentially spaced for each pass.

The invention also provides a method for exchanging heat between a first fluid and a second fluid before that a temperature different from the first fluid wherein in the method the first and second fluids through first and second fluid flow paths, which are isolated from each other by first and second sealing members and wherein between the first and second Sealing elements a third fluid flow path is formed, passed through a heat exchanger, a circulation fluid passed through the third fluid flow path and from the third fluid path entering circulation fluid is analyzed to detect traces of the determine first or second fluid in it.

Further features, details and advantages of the invention emerge from the claims, the following description of a preferred embodiment of the invention and based on the drawing. Here show:

Fig. 1 is a longitudinal section through part of an inventive trained heat exchanger;

Fig. 2 is a section along line 2-2 in Fig. 1;

Fig. 3 is a more detailed view of part of the heat exchanger and

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FIG. 4 shows a cross section of Tang along the line 4-4 in FIG. 3.

The heat exchanger according to the invention comprises a pair of end manifolds 2 between which concentric heat transfer tubes 4 are arranged. The distributors have a central bore 6 through which a long clamping bolt 7 passes which is used to clamp the pipes between the end manifolds 2. In the illustrated Embodiment there are five tubes 4, each of which is preferably made of stainless steel and has helical grooves, not shown, on its cylindrical Wall can be provided to thereby improve the heat transfer properties. The spaces between adjacent Tubes form annular fluid flow passages for the heat exchanger.

Both end manifolds 2 for the heat exchanger are identical and it is therefore only necessary to build one of the two Describe distributor.

As best seen in Figures 1 and 3, each manifold contains an approximately conical one-piece cast body portion 8 with tubular inlet / outlet sleeves 10 and 12. The sleeves 10 and 12 allow the connection of fluid lines to the end manifolds with the help of conventional Facilities. The sleeves 10 and 12 can be used interchangeably as an inlet or outlet, however in the following description it is assumed that the sleeve is used as an inlet for a first heat transfer fluid and the sleeve 12 used as an outlet for the second heat transfer fluid will. The body portion 8 includes an inlet chamber 14

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and an outlet chamber 16 connected to sleeves 10 and 12 in Connected. The conical section 8 also contains a central opening which is separated by a tube 21 Chambers 18 and 19 is divided, the ends of the tube 21 passing through the bore 6 and welded thereto are.

The outer surface of the body portion 8 of the manifold contains a series of approximately cylindrical sections 20, the are arranged spaced apart in the axial direction along the body portion 8 and are designed such that they are in corresponding Ends of the tubes 4 can be used, the cylindrical sections 20 with the help of tapered transition sections are connected. Each cylindrical section has two spaced apart grooves for receiving of 0-rings 25 for the formation of inevitable seals with the inner surfaces of the tubes 4. A shoulder is formed at the end of each of the cylindrical sections 20, to form a seat against which the ends of the tubes rest.

Fluid chambers 14 and 16 are provided with the annular fluid passages, which are formed between adjacent tubes 4, connected by means of radial recesses 28 and 29, respectively, which are introduced in the transition sections, as can best be seen from FIG.

According to the invention, a device is provided to create a flow a circulation or cleaning fluid between the corresponding pairs of O-rings 25 to enable. In the body portion 8 are between the pairs of O-rings

I » ft

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Grooves 30 are formed so that they extend along the circumference Form fluid passages for the cleaning fluid. As best seen in Figure 3, the manifold includes a cleaning fluid inlet conduit 32 which extends into the Kammer.18 opens, which has a number of approximately radially extending inlet lines 34, which with the corresponding Grooves 30 are in communication. On the opposite side of the body portion 8 is a cleaning fluid outlet conduit 36 is formed which opens into the chamber 19, which has a number of approximately radially extending return passages from the grooves 30 has. As can best be seen in FIG. 4, the cleaning fluid then flows through from the chamber 18 the passages 34 and then follows approximately semicircular paths along the grooves 30 and between the pairs of O-rings 25.

The fluid then flows into the return passages 38 and into the return chamber 19.

In one application, the cleaning fluid can be used as a coolant to cool the O-rings 25 and thereby enable the heat exchanger with Heat transfer fluids at relatively high temperatures can be used. In a second embodiment, the cleaning fluids can circulate at a pressure that is higher than the pressure of the first or second heat transfer fluids so that if a leak occurs at the O-rings 25, the cleaning fluid flows into the heat transfer passages between the tubes rather than mixing the heat transfer fluids occurs.

In another application, the cleaning fluid can be used in a Circulate low pressure compared to the pressure of the heat transfer fluids and a monitoring device is provided be to the presence of one or the other heat

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to monitor transfer f1uids in the cleaning f1uid in order to thereby providing an effective means of detecting a broken or damaged O-ring. This arrangement is shown schematically in FIG 1 uid supply 50 and a cleaning fluid analyzer connected to the outlet line 36 via a line 56 shows. The analyzer monitors the presence of traces of one or both through inlet 10 and outlet 12 of the Heat exchanger of flowing fluids. The supply and the analyzer can be operated continuously or periodically. It can be a return path for cleaning fluid from the analyzer 54 can be provided in the supply 50.

The principles of the invention can also be used, for example, in May be used in connection with the heat exchanger described in Australian Patent Specification 489 755, in any other heat exchanger that uses a pair of seals between the main fluid paths for the fluids .

Claims (1)

PATENT LAWYERS RUFF AND BEIER STUTTGART Dipl.-Chem. Dr.Ruff N β c K a rs tr a ß θ Dipl.-Ing. J. At he D-7OOO Stuttgart Dipl.-Phys Schöndorf ^ e-: CO711) 22 7Ο51 Telex Ο7-23412 erubd Applicant: John Ronald Pain June 30, 1981 Sf / S 196 Sherbourne Road
Montmorency, Victoria
Australia A 19 161
A 19 162 Heat exchanger Expectations Ii method of heat exchange between a first and a second fluid with different temperature at which the first and second fluids through first and second fluid flow paths are guided in a heat exchanger, which are isolated from each other by first and second sealing elements (25) are, wherein a third flow path (30) is formed between the first and second sealing elements (25), characterized in that that a circulation fluid is circulated through the third flow path (3Q). 2. The method according to claim 1, characterized in that the circulation fluid emerging from the third flow path (30) is analyzed to determine traces of the first or second fluid therein. »· · ► · --► *» »· w vj I Z O j j ο A 19 161/2 - 2 - "'3 / heat exchanger for fluids with a multitude of coaxial an-V_y ordered tubes (4) of thermally conductive material, fed by a pair of end manifolds (2) to form annular Fluid flow passages are kept radially spaced apart, wherein at least one of the manifolds (2) first and second sealing elements (25) for forming seals between the manifold (2) and the ends of the tubes (4) and between the first and second sealing elements (25) longitudinally circumferentially extending fluid passages are formed, characterized by a circulation fluid inlet means (32, 18, 34) for introducing a circulation fluid at first Locations in the passages (30) as well as through circulation fluid outlet means (36, 19, 38) for discharging the circulation fluid at second locations in the passages (30), the first and second locations for each passage (30) are arranged circumferentially offset from one another. 4. Heat exchanger according to claim 3 with a circulation fluid supply device (50) for supplying the circulation fluid inlet device (32, 18, 34) with circulation fluid and with a fluid analysis device (54) for receiving circulation fluid from the circulation fluid outlet device (36, 19, 38), characterized in that the analysis device (54) to detect the presence of traces of fluid in the Passages (30) in the fluid which has penetrated from the annular fluid flow passages of the heat exchanger Circulation fluid is arranged and formed. 5. Heat exchanger according to claim 3 or 4, characterized in that that the first and second locations for each passage (30) are located on diametrically opposite sides of the manifold (2) are. A 19 161/2 - 3 - 6. Heat exchanger according to one of claims 3 to 5, wherein the The manifold (2) has a substantially conical shape and the sealing elements (25) on the inner surfaces of pipes (4) attack sealingly with increasing diameter, characterized in that the passages (30) through into the outer Circumferential grooves (30) formed on surfaces of the manifold (2) are formed. 7. Heat exchanger according to claim 6, characterized in that the circulation fluid inlet device (32, 18, 34) in the essentially radial inlet ducts (34) extending from an inlet chamber (18) formed in the manifold (2) to the first Places in the passages (30) extend, and the circulation fluid outlet means (36, 19, 38) substantially having radial outlet ducts (38) which extend from one outlet chamber (19) formed in the manifold (2) to the second Extend places in the passages (30), 8. Heat exchanger according to one of claims 3 to 7, characterized characterized in that both distributors (2) are designed the same.