JPS5841625A - Device for expanding tube through explosion of detonator and combining it with tube plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for forming a joint between a tube and a tube sheet by detonating an explosive, and more particularly to a device for forming a joint using a knot member between the tube and the tube sheet.

Current heat exchangers generally have a plurality of heat exchanger tubes inserted into a tube plate, with a first fluid passing through the tubes and a second fluid flowing over the tubes. exchange heat.

Various techniques have been developed to secure these tubes within the tubesheet. For example, there is a method in which a tube is inserted into a hole in a tube sheet, and a mandrel or the like is used to mechanically expand the tube and fix it in the hole in the tube sheet, but this method is limited to low-pressure tubes. . In the case of high-pressure tubes, it is common to temporarily weld the ends of the tube to the tube and then expand the tube within a hole in the tubesheet to secure it to the tubesheet. The tubes can also be expanded mechanically within the tubesheet by rolling, ie by applying a radially outward force on the entire surface of the tubes.

However, these techniques produce localized metal tube deformation, overall longitudinal elongation of the tube, axial stress on tube welds, and compressive strain on the tube wall. It has some disadvantages such as the occurrence of

To overcome these drawbacks, techniques have been developed in which the tube-to-tubesheet joint is formed using explosives.

According to this technique, an explosive insert is loaded into the overlap between the tube and the tubesheet and is detonated to uniformly expand the tube and crimp it against the inner wall of the hole in the tubesheet. Although this technique has been generally effective, it does have some limitations. For example, if the tube and tubesheet are each made of 417I material that is not compatible with each other in terms of modulus of elasticity and coefficient of thermal expansion, optimal tube expansion will be achieved. 1. The tube and explosive inserts should be carefully sized to the surface of the tubesheet to obtain proper sizing. This is a time-consuming process and increases manufacturing costs.

In addition, if the heat exchanger is operated at a high altitude, the tubesheet is 1 mm thick, or the surrounding environment is corrosive, there should be sufficient leakage protection between the tube and tubesheet. It is difficult to set.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a device for securing a tube within a tubesheet by shaping it by detonation of an explosive within an opening in the tube and tubesheet.

Another object of the invention is to expand within the bores of the tubes and tubesheets in such a manner as to ensure high leaktightness, even if the tubes and tubesheets are made of materials that are incompatible with each other. It is an object of the present invention to provide a tube fixing device that can be used to fix a shiitake tube.

Still another object of the present invention is to develop a system f1u of the type described above, which ensures leak-proofing even when the operating body θ1λ1 is low, the tube sheet is thin, and the surrounding environment is corrosive. 1) A device of the type described in 1) without the need to weld the tube and/or the deformable charge insert to the tube sheet before shaping. It is to provide.

Another object of the invention is to provide ! between the tube and the tube sheet! , l, l, characterized in that a seal ring is provided on the surface.

BRIEF DESCRIPTION OF THE DRAWINGS The diagonal and other features and advantages of the present invention will become more apparent from the description of the illuminating embodiments of the invention, given with reference to the accompanying drawings.

Referring to FIG. 1, a tubesheet 10 holding a plurality of heat exchange tubes 12 is shown. One end of each tube J2 passes through an opening in the tubesheet and communicates with a region on the other side of the tubesheet. 1st
Although only a portion of the tubesheet 10 and tubes 12 are shown, the heat exchanger surrounds the tubesheet and includes suitable inlets for the first heat exchange fluid and the second heat exchange fluid. A container with an outlet is provided. In the case of this divine heat exchanger, tube 12
is U-shaped, and both ends thereof can extend through the tube sheet 10. The first heat exchange fluid is tube plate 1 as seen in FIG.
A partition plate is provided which allows the first heat exchange fluid to flow into one end of each tube 12 from the area below the tube plate, and while passing through the tube, the first heat exchange fluid enters one end of each tube 12 from the region below the tube plate. It exchanges heat with the heat exchange fluid and exits through the other end of the tube to the area below the tubesheet.

FIG. 2 shows the v12 in the tubesheet 10 with the apparatus of the present invention for assembling the tubes into the tubesheet by explosive detonation in a manner that establishes a leak-tight seal along the tube-to-tubesheet interface. It is shown inserted into the opening.

14 is a continuous (uninterrupted) groove formed in the inner wall of the tube sheet lO. The groove 16 has a rectangular cross-section, and a 7-ring ring 16 made of an elastomer is fitted snugly into the groove, with a 1.degree. The tubular member 22 is fitted with an insert 18 consisting of a central member 20, a tubular member 22, and a beak 24 extending between them. The tubular member 22 has an outer diameter slightly smaller than the inner diameter, and one end of the tubular member 22 has an outer diameter that engages the end of the tube 12 in order to accurately position the tubular member 22 and thus the entire insert 18 within the tube 12. A matching shoulder portion 26 is provided.The portion fA' 20 and 2
2 is the length of tube 12 when installed in the tube as shown.
The length of the annular member 24 is such that the length of the annular member 24 is such that the length of the annular member 24 is such that the member 20. It is shorter than the length of .

At the end of the cylindrical member 22, the end portion of the central member 20 is connected to the tube 1.
A cap 29 is fitted, which serves to position it relative to 2.

The central member 20 contains a predetermined number of explosive particles (grains). Usually uniformly length 1 along the axis of the central member
1 containing 25 to 40 explosive particles per ft.
, this 1] is suitable for "Puri 7 Kobi"
There is a material called. "Primaco-1:'" is a product formed by immediately placing explosive particles inside a fibrous body or a plastic body. A cylindrical member 22 and an annular member 24d1 that play a role of transmitting information,
It can be extruded with the center side 20 and then cut to the desired length. Center i'ilt in the area of shoulder 26
The air gap 28 present around the AA' 20 serves to inhibit excessive forces from being transmitted through the free end of the tube 12. The force transmitting member 22.24 is made of polyethylene, dimension d, Other thermoplastics V1 with substantially the same properties
FIG. 3 shows that the explosive is detonated and the tube 12 and seal ring 16 expand accordingly.
, y indicates 1-1-arrival i'. A portion 12a of the tube J2 expands more than the other portion of the tube, presses against the ring 16, and presses into the groove 14.

This seals the ring 16 under considerable pressure, thereby increasing leak tightness along the interface between the tube 12 and the tubesheet 10.

This excellent leakage fit is obtained even if the tube 12 and the tubesheet 10 are made of materials that are incompatible with each other in terms of coefficient of expansion. It can be made of titanium, and the tubesheet 10 can be made of carbon steel.

Seal ring 16 may be formed from an elastomeric material such as rubber or plastic, or from a metal ring size or band having a modulus of elasticity compatible with the material of tube 12 and tubesheet 10.

In the variant embodiment of FIG. 4, a groove 30 in the form of an enlarged hole is formed in the tube sheet 10. ? 7/#30 has a cross-sectional shape that extends inward in the radial direction from the lower surface of the tube sheet 10 to the midpoint between the lower surface. Groove 30 can be formed in the tube by conventional reaming.

A seal ring 32 is interposed between the outside 1.51 of the tube 12 and the wall of the groove 30 at a position slightly above the bottom surface of the tube plate 10. The ring 16 has a cross-sectional area slightly smaller than that of the ring 16.

The insert 18 of the embodiment of FIG. 4 is the same as that of the embodiment of FIG. 2, except that the shoulder 26 from the cylindrical force transmission member 22 is omitted.

Figure 5 shows the tube sheet l being expanded by the explosion of the explosive.
The tube 12 in FIG. 4 after being crimped against the inner wall of the opening
shows. The lower end portion of the tube is expanded outwardly to match the contour of the groove 30, and as a result of the lower end portion being pressed against the sealing ring 32, a slightly inwardly bulging portion 12b is formed.

? p, 6 shows yet another real M similar to the embodiment of FIG.
Example II is shown. In the embodiment shown in FIG. 6, an elongated groove 34 similar to the groove 30 is formed in the inner wall of the tube sheet 10. 71'/
The lower end portion of 134 is of uniform diameter, but the remaining portion tapers inwardly upward as shown.

An elongated, cylindrical seal portion 4'A' 3 G is attached to the groove 34 so as to occupy most of the groove. The outer surface of the sealing member 36 conforms to the shape of the rttt 34, but the inward direction of the knoll H is shorter than the length of the outer surface and the tube 12
engages a portion of the outer surface of the The insert 18 of the embodiment of FIG. 6 is the same as that of the embodiment of FIG.

The tube 12 of FIG. 6, after being expanded by the explosion of the explosive and crimped against the wall of the opening in the tube sheet 1.0, assumes the shape shown in FIG. 7, with its lower end portion facing outward. It is crimped onto the cylindrical sealing member 36.

The seals 32, 34 in FIGS. 4 and 6 are also sealed under pressure as a result of the expansion of the tube 12, as in the embodiment of FIG. Set.

As above, any embodiment of the present invention forms an excellent leakage interface between the tube and its corresponding portion of the tubesheet;
Moreover, the interposition of the sealing between the two makes it possible to use tubes and tube sheets made of materials that are incompatible with each other. However, the device of the present invention requires no welding, is easy and efficient to operate, and can be used even with low operating temperatures, thin tubesheets, and/or corrosive ambient circulation. can.

Another advantage of the present invention is that even if the area of containment of the reseal section changes due to the difference in coefficient of thermal expansion between the tube and the tubesheet, the elasticity of the sealing member prevents leakage from occurring. is to be maintained.

The present invention is not limited to the embodiments disclosed herein, but without departing from the spirit and scope of the invention.
Various changes and modifications are possible. 3, +4, Brief Description of the Drawings Figure 1 is a partial cross-sectional view of a tube plate of a typical heat exchanger having a plurality of heat exchange tubes; An enlarged view showing the tube/tubesheet interface containing the device; FIG. 3 a cross-sectional view of the tube after it has been shaped by explosive detonation in the tubesheet; FIG. 4 a modified embodiment of the device of the invention. FIG. 5 is a view similar to FIG. 4 showing the tube after it has been crimped into the tube sheet by detonation of an explosive, and FIG. 6 shows a further embodiment of the device of the present invention. The cross-sectional view, FIG. 7, is a view similar to FIG. 6 showing the tube after it has been crimped into the tubesheet by explosive detonation.

In the figure, 10 is a tube plate, 12 is a tube, l 4171. ' m,
16 is a seal ring, 18 is an insert body, 2011J, published by Chubu, 22 is a cylindrical member, 24 is an annular member 1, patent applicant Foster Wheeler Energy.
Amendment to Procedures (Method) Kazuo Wakasugi, Director-General of the Special IFI Agency, October 14, 1981. 1 ・+11'l Nor Show I+ 57τ1-! Samurai Permit No. 97890 2, Title of the Invention Inflating the tube due to the explosion of exposed chemicals for 3-h
li', +T', V-iZp Relationship with device type PI for coupling to tube sheet! Chamberlain Applicant 11 Mr. '(+ (Name) Foster ° Wheeler °
Energy.

Corporation 1'i, F+li 'i1', the number of inventions increases (2) Drawings (clean store, no change in content) (3) Power of attorney and translation 8 Contents of amendment Attachment. Tooshi133-

Claims (1)

[Claims] In a device for fixing a tube in an opening in a tube plate,
a "card seal" disposed within a groove formed in the wall of the tube plate defining said opening; and a dowel insert inserted into said tube, said insert containing a central portion containing an explosive charge. the central member and tube in order to transmit the explosive force from the explosive to one of the limbs and the sealing system to seal the interface between the limb and the tube plate. A device characterized by comprising a force transmitting section 4A extending between the inner wall and the inner wall.