JP2000028080A - Fluid insulating transport tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid transport tube excellent in insulation property and excellent in strong durability against mechanical strength. SOLUTION: A first flange 4a is attached to the inner wall of one end side of an extendible/shrinkable bellows tube 4, and also a second flange 4b is attached to the outside diameter of the other end side thereof, the peripheral surface of this transport tube 1 is welded to the first flange 4a of the bellows tube 4, the transport tube 1 is fitted to the inside of an insulating tube 2 having larger diameter than the transport tube 1, the end of the insulating tube 2 is welded to the periphery of the first flange 4a of the bellows tube 4 so as to form a double tube by these insulating tube 2 and transport tube 1, this double tube is inserted in the inside of an outermost tube 5 having larger diameter than the insulating tube 2, the end of the outermost tube 5 is welded to the end surface of the second flange 4b of the bellows tube 4 so as to form a whole into a triple tube, and evacuating/depressurizing treatment is applied between the transport tube 1 and the insulating tube 2 and between the insulating tube 2 and the outermost tube 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid heat-transporting pipe for transporting a cooling medium or a high-temperature fluid and having excellent heat-retaining properties.

[0002]

2. Description of the Related Art Hot springs and the like are transported to a distant inn or hotel using a transport pipe while maintaining a predetermined temperature, but are transported over long distances using the conventional transport pipe. In some cases, the fluid may drop in temperature or change in temperature when it reaches the terminal end location. In particular, when transporting hot spring water from a hot spring source to an urban area, the temperature of ordinary synthetic resin pipes drops sharply, and a sufficient temperature cannot be maintained.
In some cases, a metal transport pipe is used. However, the transport pipe has a large coefficient of thermal expansion, and in some cases, expansion or contraction of the transport pipe in a heat source device or a terminal connecting portion may damage the device wall. In particular, chemical plants and the like also use heat retaining tubes for transporting while maintaining the fluid temperature, but many of them are expensive.

[0003]

It has been desired to suppress the temperature change and supply the fluid while maintaining the initial temperature of the fluid. In addition, there is a need in the market for a transport pipe that can cope with thermal expansion or thermal contraction and that does not damage the device at the terminal connection part.

[0004] An object of the present invention is to provide an excellent heat retaining property and
An object of the present invention is to provide a fluid heat-insulating transport pipe having high mechanical strength and excellent durability.

[0005]

According to the present invention, a first flange is mounted on an inner wall at one end of a telescopic bellows tube, and a second flange is attached to an outer diameter at the other end. The transportation pipe is fitted into the bellows pipe, the inner circumference of the first flange of the bellows pipe is welded to the outer circumference of the transportation pipe, and the transportation is performed into the heat insulation pipe having a diameter larger than the transportation pipe. A pipe is inserted, and the end of the heat retaining pipe is welded to the outer periphery of the first flange of the bellows pipe to form a double pipe of the transport pipe and the heat retaining pipe. The outermost tube is inserted into a large outer tube, and the end of the outermost tube is welded to the end face of the second flange of the bellows tube so as to form a triple tube, and between the transport tube and the heat insulating tube and the heat insulating tube. Vacuum decompression treatment was performed between the tube and the outermost tube.

The present invention can achieve the above object by a configuration in which a radiant heat reflecting foil having a thickness of several microns is wound on three or more layers on the outer periphery of each of the transport pipe and the heat retaining pipe. Further, the fluid heat-insulating transport pipe of the present invention can achieve the above object by providing at least one suction hole in the heat-insulating pipe or the bellows pipe and the outermost pipe, and sealing them after suction under reduced pressure.

In the fluid heat-retaining transport pipe of the present invention, the heat-retaining pipe and the outermost pipe are arranged outside the transport pipe, and the gap between them is evacuated to form a triple pipe. It is possible to prevent the temperature change of the fluid due to the outside air. For example, even when a high-temperature fluid flows in the transport pipe, the temperature drop of the fluid can be suppressed, and the adverse effect due to the temperature drop can be prevented. . In addition, since the fluid-insulated transport pipe has a bellows pipe that can extend and contract at a connection portion of the transport pipe, a change in length due to expansion or contraction of the transport pipe due to a temperature change of the fluid can be absorbed. Therefore, there is no possibility that the devices at the end portions of these transport pipes are destroyed at the connection portion.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A heat insulating transport pipe according to the present invention is provided with a heat insulating pipe connected by a bellows pipe outside the innermost transport pipe, and a second flange having the outermost diameter of the bellows pipe. And the outer peripheral surface of the transport tube is welded to the inner surface of the first flange provided at the other end of the bellows tube, and the end of the heat insulating tube is attached to the outer peripheral surface of the first flange. Is provided on the peripheral wall of the heat insulating pipe or the bellows pipe, and a suction hole communicating the gap between the transport pipe and the heat insulating pipe and the gap between the heat insulating pipe and the outermost pipe is provided. Then, the air is sucked to reduce the pressure, and then the suction hole is closed, fitted into the outermost tube to form a triple tube, and further reduced in pressure through the suction hole provided in the peripheral wall of the outermost tube. The pressure is reduced by the treatment. The heat insulation effect is doubled by this triple pipe, and the temperature of the fluid transported in the transport pipe is sufficiently maintained.

Such a heat-insulated transport pipe has a further heat-insulating effect by winding several layers of radiant heat-reflective metal foil on the outer peripheral surface of the inner transport pipe and the heat-insulated pipe. In particular, by using an array of sharp projections on one side as the radiant heat reflecting foil, when the radiant heat reflecting foil is wound into several layers, a vacuum layer is formed in the gaps between the radiant heat reflecting foils and the radiant heat is formed. Excellent reflection effect.

[0010] Various pipes made of various materials can be used for the inner transport pipe, the thermal insulation pipe, and the like used in the fluid thermal transport pipe of the present invention, which have a low thermal expansion property and an excellent heat insulating effect. Although a stainless steel tube is preferable, a stainless steel tube is most preferable in terms of durability.

The bellows tube used in the present invention is preferably made of a metal having the same quality as the transport tube. The metal sheet is bent into a bellows-like shape to form a tubular shape, the entirety of which is expandable and contractable, and can be connected to an end of a transport pipe or a heat retaining pipe by welding.

FIG. 1 is a partial cross-sectional view of an embodiment of the fluid heat transfer pipe of the present invention. FIG. 2 is a partial cross-sectional view in which a radiant heat reflecting foil is wound around the fluid heat transporting pipe of FIG. FIG. 3 is an exploded perspective view of the fluid heat transporting pipe of the present invention.

Reference numeral 1 denotes a stainless-steel transport pipe of a predetermined length for transporting a fluid requiring heat retention. The heat retaining pipe 2 which is slightly larger than the transport pipe 1 may be connected to the two via a central bellows pipe 3. Both ends of the central bellows tube 3 are welded to the ends of the heat insulating tube 2 so that the heat insulating tube 2 has a predetermined length.
It corresponds to the length of the transport pipe 1. The first and second flanges are not attached to the central bellows tube 3. At least one suction hole 3 a is provided in a part of the central bellows pipe 3, and the transport pipe 1 is inserted into the heat retaining pipe 2 connected by the central bellows pipe 3,
The first flange 4a side of the bellows pipe 4 is welded to the outer peripheral surface of the transport pipe 1. Next, the end of the heat insulating pipe 2 on the same side is welded to the outer peripheral side of the first flange 4a, and the heat insulating pipe 2 is pressed against the welded side from the opposite side to shrink the bellows pipe 4 and the central bellows pipe 3. The other end of the transport pipe 1 is welded and fixed to the inside of the first flange 4'a of the bellows pipe 4 ', and further, the heat insulating pipe 2 is placed outside the first flange 4'a of the bellows pipe 4'. The end of is welded.

The air is sucked from the suction hole 3a of the double pipe formed by inserting the transport pipe 1 into the inside of the heat retaining pipe 2 and the pressure is reduced to a predetermined value, and the suction hole 3a is sealed. Next, the heat insulating tube 2 is inserted so that the outermost tube 5 slightly larger than the heat insulating tube 2 is disposed outside. Second of the bellows tube 4
Is welded to the outer diameter of the flange 4b. Thereafter, the other end of the outermost tube 5 is welded to the second flange 4'b of the bellows tube 4 '. In this way, the entirety can be formed as a triple pipe of the transport pipe 1, the heat retaining pipe 2 and the outermost pipe 5. The gap between the outermost tube 5 and the heat-retaining tube 2 is suctioned through a suction hole provided on the peripheral wall of the outermost tube 5 and subjected to a pressure reduction process.

The length of the thus formed triple heat transfer pipe can be freely adjusted. For example, the pipe is used when transporting hot spring water from a spring flowing from a hot spring to an inn or a hotel in an urban area. can do. Further, it can be used when transporting a cooling medium or a heat retaining medium in a factory.

When used in this manner, the fluid transported in the transport pipe 1 is excellent in heat retention. However, if it is insufficient, the radiation heat reflecting foil 6 can be further wound on the outer peripheral surface of the transport pipe 1 in several layers to reflect the internal radiant heat. The layers may be wound (see FIG. 2).

[0017]

According to the fluid heat transfer pipe of the present invention, a number of bellows pipes are arranged in the middle and the outermost pipe and the heat insulation pipe and the space between the heat insulation pipe and the transfer pipe are decompressed to a vacuum. Excellent, the initial temperature of the fluid flowing in the transport tube is maintained. In addition, a change in the length of the transport pipe due to expansion and contraction of the transport pipe due to the temperature of the transported fluid is absorbed by the bellows pipe, and does not damage the fluid transport device, the terminal liquid tank, the bathtub, and the like.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of an embodiment of a fluid heat retaining transport pipe of the present invention.

FIG. 2 is a partial cross-sectional view in which a radiant heat reflecting foil is wound inside the fluid heat transporting pipe of FIG. 1;

FIG. 3 is an exploded perspective view of the fluid heat transporting pipe of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Transport pipe 2 ... Heat insulation pipe 3 ... Central bellows pipe 4, 4 '... Bellows pipe 5 ... Outermost pipe 6 ... Radiation heat reflection foil

Claims (3)

[Claims] 1. A first flange is attached to an inner wall of one end side of a telescopic bellows tube, and a second flange is attached to an outer diameter of the other end side of the bellows tube. The inner peripheral surface of the first flange of the bellows pipe is welded to the outer peripheral surface of the pipe, the transport pipe is inserted into a heat retaining pipe having a diameter larger than that of the transport pipe, and the outer circumference of the first flange of the bellows pipe is The ends of the heat insulation pipe are welded to form a double pipe of the transport pipe and the heat insulation pipe, the double pipe is inserted into the outermost pipe having a diameter larger than that of the heat insulation pipe, and the end of the outermost pipe is connected to the bellows. The entirety is formed into a triple pipe by welding to the end face of the second flange of the pipe, and a vacuum decompression process is performed between the transport pipe and the heat retaining pipe and between the heat retaining pipe and the outermost pipe. And the fluid insulation transport pipe. 2. The fluid-insulated transport tube according to claim 1, wherein a radiant heat reflecting foil having a thickness of several microns is wound in three or more layers around each of the transport tube and the heat-insulated tube. 3. The fluid thermal insulation transport according to claim 1, wherein at least one suction hole is provided in the heat retaining tube or the bellows tube and the outermost tube, and each of the holes is sealed after decompression suction. tube.