JPH10311496A - Double pipe for high temperature and high pressure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a local high temperature heating by a high temperature gas, and to absorb the thermal extension difference between inner pipes and an outer pipe rationally, in a double pipe for high temperature and high pres sure, and furthermore, to easily carry out the manufacture and the assembly of the double pipe for high temperature and high pressure. SOLUTION: This double pipe for high temperature and high pressure has inner pipes 3 and 3a, and an outer pipe 1, the connecting parts of the inner pipes 3 and 3a are connected by an inner screw type inner pipe support metal fitting 15, and a gasket 16 to seal the circular clearance between the inner pipes 3 and 3a, and the outer pipe 1, is sliding contacted to at least one side peripheral surface of the outer peripheral surfaces of the inner pipes 3 and 3a, and the inner peripheral surface of the outer pipe 1, to the outer peripheral surfaces of the inner pipes 3 and 3a, for example.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention can be applied to, for example, high-temperature and high-pressure ducts for hypersonic wind tunnels, and large-diameter high-temperature ducts for steelworks or chemical plants.
It relates to a double pipe for high temperature and high pressure.

[0002]

2. Description of the Related Art FIG. 4 is a schematic plan view of a hypersonic wind tunnel device for explaining an application example of a high-temperature and high-pressure double pipe, and FIG. 5 is a longitudinal sectional view of a main part of a conventional high-temperature and high-pressure double pipe. 6, FIG. 6 is an enlarged sectional view of a part A of FIG. 5, and FIG. 7 is an enlarged sectional view of a part B of FIG.

First, in FIG. 4, high-temperature and high-pressure air sent from a high-temperature and high-pressure air source 21 of a hypersonic wind tunnel device to a high-temperature and high-pressure duct 20 via an on-off valve 21a is applied to a high-temperature and high-pressure duct 2
The wind tunnels 22a and 22b are respectively provided through gate valves 23a and 23b provided for each of the T-shaped branch pipes 20a and 20b.
Sent to The exhaust gas discharged from each of the wind tunnels 22a and 22b is discharged through an exhaust pipe 24. The high-temperature high-pressure duct 20 transports high-temperature air of, for example, 900 ° C. and high-pressure of 100 ata.

Referring to FIGS. 5, 6 and 7, for example, T-shaped branch pipes 20a and 20b of a high-temperature and high-pressure duct 20 shown in FIG.
Is a double pipe structure having an outer cylinder 1, an inner cylinder 3, and an inner cylinder 3a.
A high-pressure flange 2 is formed at each of the connection ends of the outer cylinder 1, and an annular gap between the outer cylinder 1 and the inner cylinders 3 and 3 a is filled with a heat insulating material 5 such as ceramic wool. Have been.

[0005] As shown in FIGS. 5 and 6, the inner cylinder 3 and the inner cylinder 3 a are located adjacent to each other between the inner cylinder 3 and the inner cylinder 3 a.
An axial gap 13 is formed between the inner cylinder 3 and the inner cylinder 3a so as to absorb the axial elongation caused by the heat of the inner cylinder 3 and the inner cylinder 3 and the inner cylinder 3 centered on the gap 13. 3a, the inner cylinder 3 and the inner cylinder 3a
In order to be able to absorb the elongation in the radial direction due to the heat of the inner cylinder 3, an annular inner cylinder support fitting 6 is arranged with an annular gap 14 in the radial direction from the outer peripheral surfaces of the inner cylinder 3 and the inner cylinder 3a. I have.

As shown in FIGS. 5 and 7, on the inner peripheral side of each high-pressure flange 2 of the outer cylinder 1, axial and radial expansion due to heat at the end of the inner cylinder 3 or the inner cylinder 3a is absorbed. So that the inner cylinder 3 and the inner cylinder 3a
An annular end support fitting 6 is disposed at an annular gap 12 in the radial direction from the outer peripheral surface of the annular support member 6. The outer peripheral edge of the annular end seal member 8, whose inner peripheral edge is integrally fixed to the outer peripheral surface side of the end support member 6, is annular from the front and back sides as viewed in the axial direction of the outer cylinder 1. In a state where the outer cylinder 1 is held by the sealing gasket 11a,
Is fixed to the outer cylinder 1 side by a tightening screw 10 so as to be pressed down while being fitted to the annular shoulder portion.

[0007]

In a high-temperature and high-pressure double pipe such as the T-shaped branch pipes 20a and 20b of the high-temperature and high-pressure duct 20, it is difficult to use an expansion joint for the outer cylinder 1 because of its high pressure. In addition, since it is difficult to adopt a two-split structure in the outer cylinder 1 from the viewpoint of insufficient strength against high pressure and an increase in manufacturing cost, etc., in consideration of ease of assembly, conventionally, As described above, the difference in the elongation rate due to heat between the outer cylinder 1 and the inner cylinder 3 is eliminated by forming the gaps 12, 13, and 14 anywhere. Then, in order to shorten the temperature rise time, a heat insulating material 5 such as ceramic wool having no sealing function is filled between the outer cylinder 1 and the inner cylinders 3 and 3a.

However, a high-temperature and high-pressure double pipe such as the T-shaped branch pipes 20a and 20b of the conventional high-temperature and high-pressure duct 20 is used.
For example, when used at a temperature of 900 ° C. and a pressure of 100 ata, local overheating occurs in which the temperature of the outer cylinder 1 greatly exceeds the allowable temperature of 250 ° C. The cause is 900
As shown by dotted arrows in FIGS. 6 and 7, high-temperature gas at a temperature of .degree. C. flows through gaps 12, 13 and 14 provided in the T-shaped branch pipes 20a and 20b into a heat insulating material 5 such as cotton-like ceramic wool. It is presumed that the fluid leaks out to contact the outer cylinder 1 directly.

Therefore, the present invention is to provide a high-temperature and high-pressure double tube capable of preventing local high-temperature heating by high-temperature gas and facilitating manufacture and assembly. Is what you do.

[0010]

In order to solve the above-mentioned problems, a high-temperature and high-pressure double pipe according to the present invention has a connection part between inner pipes connected by a joint, and a pipe between the inner pipe and the outer pipe. A gasket that seals the annular gap is in sliding contact with at least one of the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional view of a main part of a double pipe for high temperature and high pressure according to an embodiment of the present invention, and FIG.
FIG. 3 is an enlarged sectional view of a part B in FIG.

In FIG. 1 to FIG. 3, the double pipe for high temperature and high pressure has a double pipe structure having an outer cylinder 1, an inner cylinder 3 and an inner cylinder 3a. Each has a high-pressure flange 2 formed therein, and an annular gap between the outer cylinder 1 and the inner cylinders 3 and 3a is provided with, for example, ceramic wool, a multi-layer metal thin-film heat insulating material, a refractory brick, a refractory mortar. The heat insulating material 5 selected from such heat insulating materials is filled.

As shown in FIGS. 1 and 2, the connection between the inner tubes 3 and 3a of the high-temperature and high-pressure double tube is connected by an annular inner-screw-type inner cylinder support fitting 15 as a joint.
Further, a sliding contact gasket 16 for sealing an annular gap between the inner pipes 3 and 3a and the outer pipe 1 is provided on at least one of the outer peripheral faces of the inner pipes 3 and 3a and the inner peripheral face of the outer pipe 1. For example, as shown in FIGS. 1 and 3, the outer pipes 3 and 3a are in sliding contact with the outer peripheral surfaces of the inner pipes 3 and 3a.

In FIGS. 1 and 2, an inner peripheral surface on the proximal end side of an inner screw type inner cylinder support fitting 15 as a joint is provided on an outer peripheral surface of a connection end of an inner cylinder 3a connected to the inner cylinder 3. In the fitted state, the base end side of the inner screw type inner cylinder support fitting 15 is welded on the outer peripheral surface of the connection end of the inner cylinder 3a, and further, the inner circumference of the distal end side of the inner screw type inner cylinder support fitting 15 An inner thread is formed on the surface, and an outer thread is formed on the outer peripheral surface of the connection end of the inner cylinder 3. The inner tube 3 and the inner tube 3a are connected to each other by the inner screw being screwed to the outer screw on the outer peripheral surface of the connection end of the inner tube 3.

When assembling the inner cylinder 3a, an external screw is previously formed on the outer peripheral surface of the connection end of the inner cylinder 3 and the inner screw type inner cylinder support fitting 15 is formed on the outer peripheral surface of the connection end. After inserting the welded inner cylinder 3a into the outer cylinder 1, the inner cylinder 3a is rotated around the central axis to thereby connect the inner cylinder 3a to the inner cylinder 3 via the inner screw-type inner cylinder support fitting 15. Connecting. As a result, it is possible to eliminate the gap between the inner cylinder 3 and the inner cylinder 3a, which is the largest cause of local overheating.

In FIGS. 1 and 3, an outermost flange portion of an annular gasket holder 17 is provided at an innermost annular portion on the inner peripheral side of a high-pressure flange 2 formed at an end of an outer cylinder 1 with a gasket holder. It is fixed by a screw 18 for use. An annular sliding contact gasket 16 made of, for example, ceramic is held on the inner peripheral shoulder of the gasket holder 17 so as to make sliding contact with the outer peripheral surface of the inner cylinder 3 or the inner cylinder 3a. The sliding contact gasket 16 is formed by an annular projection formed on the inner peripheral edge of the gasket retainer 19 pressed against the gasket holder 17 via the end sealing gasket 11 between the gasket holder 17 and the outer surface of the gasket holder 17. The gasket holder 17 is pressed against the inner peripheral side wall surface of the gasket holder 17. The gasket retainer 19 is formed on the outer peripheral side of the gasket retainer 19 by an annular end contact plate 9 via an annular end sealing gasket 11.
Of the end shoulder plate
Are fastened and fixed on the wall surface of the outermost shoulder of the outer cylinder 1 by a fastening screw 10.

As described above, the connection between the inner pipes 3 and 3a of the high-temperature and high-pressure double pipe is, as shown in FIGS. 1 and 2, an annular inner screw-type inner cylinder support fitting 15 as a joint.
And a gasket 16 that seals an annular gap between the inner pipes 3 and 3a and the outer pipe 1,
At least one of the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube 1, for example, as shown in FIGS.
Since the outer cylinder 3a is in sliding contact with the outer peripheral surface of the inner cylinder 3a, the leakage of the high-temperature gas from the inner cylinders 3 and 3a to the outer cylinder 1 can be suppressed as much as possible. When,
An elongation difference between the elongation of the outer tube 1 and the elongation of the outer tube 1 is determined, for example, by a sliding contact gasket 16 made of ceramic and at least one of the outer surfaces of the inner tubes 3 and 3a and the inner surface of the outer tube 1, for example, the inner tube. It is absorbed by the free extension of the inner cylinder 3 and the inner cylinder 3a in the axial direction of the outer cylinder 1 due to the sliding with the outer surfaces of the outer cylinder 3 and 3a.

1 to 3, a T-shaped branch pipe has been described as a double pipe for high temperature and high pressure according to the present invention.
The high-temperature and high-pressure double pipe of the present invention can be applied to a high-temperature and high-pressure double pipe having any other shape, for example, a high-temperature and high-pressure double pipe formed of a straight pipe duct.

[0019]

As described above, according to the double pipe for high temperature and high pressure of the present invention, the connection between the inner pipes is connected by the joint,
Since the gasket that seals the annular gap between the inner tube and the outer tube is in sliding contact with at least one of the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube. There is no need to form a gap between the inner pipes adjacent to each other in the axial direction to absorb the thermal elongation of the inner pipes, the inner pipes are connected by joints, and the hot gas flows from the inner pipe side to the inner pipe and the outer pipe. Does not leak into the gap between the inner tube and the inner tube, thereby preventing local high-temperature heating of the outer tube by the high-temperature gas, and at least one of the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube. Due to the action of the gasket that makes sliding contact with one of the peripheral surfaces, the inner pipe and the outer pipe are connected in a state where the hot gas does not flow from the inner pipe side into the gap between the inner pipe and the outer pipe. The difference in thermal elongation is easily absorbed, and the structure of the high-temperature and high-pressure double pipe is simple. Next, it is easy to manufacture and assembly (claim 1).

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a main part of a double pipe for high temperature and high pressure according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a portion A in FIG.

FIG. 3 is an enlarged sectional view of a portion B in FIG. 1;

FIG. 4 is a schematic plan view of a hypersonic wind tunnel device for explaining an application example of a double pipe for high temperature and high pressure.

FIG. 5 is a longitudinal sectional view of a main part of a conventional double pipe for high temperature and high pressure.

FIG. 6 is an enlarged sectional view of a portion A in FIG. 5;

FIG. 7 is an enlarged sectional view of a portion B in FIG. 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer cylinder 2 High-pressure flange 3, 3a Inner cylinder 5 Insulation material such as ceramic wool 6 Inner cylinder support metal 7 End support metal 8 End seal metal 9 End plate 10 Tightening screw 11, 11a Gasket for end seal 12, 13, 14 Gap 15 Inner screw type inner cylinder support fitting as joint 16 Sliding contact gasket 17 Gasket holder 18 Screw for gasket holder 19 Gasket retainer 20, 20a, 20b High-temperature high-pressure duct 21 High-temperature high-pressure air source 21a On-off valve 22a, 22b Wind tunnel 23a, 23b Gate valve 24 Exhaust

Claims (1)

[Claims] A gasket for sealing a gap between an inner tube and an outer tube is connected to a joint between the inner tubes and a joint between the inner tube and an outer tube. Characterized in that it is in sliding contact with at least one of the peripheral surfaces thereof.