JP6778660B2 - Outer clamp type high pressure seal jig - Google Patents

Description

The present invention relates to an outer clamp type high pressure sealing jig for sealing both ends of each heat transfer tube during a pressure resistance test of, for example, a multi-tube heat exchanger such as a boiler.

For example, in a multi-tube heat exchanger mounted on a boiler or the like, the working fluid is used under high pressure and high temperature conditions. Therefore, the manufactured heat exchanger is subjected to a pressure resistance test at the final stage, and it is inspected that there is no defect or the like as a heat exchanger due to water leakage at a predetermined pressure or insufficient strength.

Such a multi-tube heat exchanger is a heat exchanger having a structure in which a large number of heat transfer tubes (tubes) are arranged inside the body. As this heat transfer tube, the strength and corrosion resistance are improved by using a rifle tube having a spiral rifling process on the inner peripheral surface of the tube. In order to perform a pressure resistance test, it is necessary to seal the end of each heat transfer pipe at the joint with a high pressure hose for supplying and discharging high pressure water, and in many cases, both ends of the pipe are sealed by welding.

When sealing the pipe end by welding in this way, as a procedure required for the pressure resistance test,
(1) Welding work,
(2) Pressure resistance test,
(3) Removal of welded parts,
(4) Grooving of both ends of the heat transfer tube is required, and many of these processes require the skill and time of the operator, which is a factor that increases the manufacturing cost.

Therefore, in order to shorten the time and reduce the cost, a pipe end sealing jig is used to seal the heat transfer tube end. As such a sealing jig, a plug that clamps and seals the rifle tube on the outer peripheral surface has been proposed (see, for example, Patent Document 1).

U.S. Pat. No. 5,676,174 Jikkai Sho 57-105948 Jikkai Sho 57-92149

Such a conventional sealing jig has a structure in which the rifle tube is clamped and sealed from the outside, and it is necessary to further have a retaining mechanism for resisting the high pressure in the tube during the pressure resistance test. Therefore, there is a problem that it is difficult to reduce the size of the sealing jig itself. As a result, in such a high-pressure sealing jig that clamps and seals the rifle pipe from the outside, there is a problem that adjacent high-pressure sealing jigs interfere with each other when the pipe pitch in the body is narrow. ..

On the other hand, a rifle tube that engages with the rifle tube on the inner surface side has also been proposed (see Patent Document 2 and Patent Document 3). However, in this case, it is necessary to manufacture a sealing jig so that the engaging portion fits into the shape of the rifling on the inner peripheral surface of the pipe, and there is a problem that it lacks versatility and economy.

An object of the present invention is to obtain a high-pressure sealing jig for a pipe end portion, which is a method of clamping the pipe end portion from the outside and does not leak even when a high pressure is applied. More specifically, it can be firmly clamped to the pipe end, enabling high-pressure sealing of the pipe end without welding work, which greatly shortens the time required for pressure resistance tests and reduces costs. It is an object of the present invention to obtain a jig, to obtain a high-pressure sealing jig having excellent safety even under pressure, and to obtain a high-pressure sealing jig that facilitates miniaturization of the sealing jig.

The outer clamp type high pressure sealing jig according to the invention according to claim 1 is a flow in which a high pressure fluid from a high pressure hose is introduced into an end portion of a heat transfer tube of a multi-tube heat exchanger while sealing this end portion. A high-pressure sealing jig for mounting a plug with a hose.
A plurality of collet members that individually move in the radial direction of the heat transfer tube and clamp the outer peripheral surface of the heat transfer tube with respect to the end portion of the heat transfer tube.
A sleeve member having a fitting hole formed in the plurality of collet members so as to be slidable from the outside and to be fitted around the heat transfer tube axis so as to be relatively non-rotatable.
A sealing means for liquid-tightly sealing the plug and the end of the heat transfer tube,
A connecting mechanism for connecting the sleeve member and the plug is provided.
The connecting mechanism
It has a cover member having a through-hole-shaped female screw hole formed in the center fixed to the sleeve member, and a male screw process formed on the outer peripheral surface of the plug and screwed into the female screw hole.
With the ring-shaped squeeze packing that presses and seals the outer peripheral surface of the end portion of the heat transfer tube arranged between the rear end portion of the collet member and the end portion of the plug, the screw of the plug is advanced to advance the sleep. It connects the member and the plug,
The outer wall surface of the plurality of collet members in contact with the sleeve member forms a tapered surface that gradually decreases toward the center side of the heat transfer tube axial direction, and the inner wall surface of the fitting hole of the sleeve member. However, tapered surfaces that slidably abut each other at the same inclination angle as the tapered surfaces of the plurality of collet members are formed.
The plurality of collet members move toward the center of the heat transfer tube along the axial direction of the heat transfer tube with respect to the sleeve member, so that the distance between the plurality of collet members becomes smaller and the ends of the heat transfer tube are tightened.
It is characterized in that a large number of spike-shaped projecting portions are formed on the clamp surface of the plurality of collet members to the heat transfer tube.

The outer clamp type high-pressure sealing jig according to the second aspect of the present invention has a plurality of spike-shaped projecting portions formed on the clamp surface of the collet member according to the first aspect to the heat transfer tube. The vertical cross section along the axial direction of the heat transfer tube is characterized by having a tooth-shaped protruding portion with a sharp tip.

The outer clamp type high-pressure sealing jig according to the third aspect of the present invention has a plurality of spike-shaped protruding portions formed on the clamp surface of the collet member according to the second aspect to the heat transfer tube. However, it is characterized in that it is 50 ° to 70 °.

The outer clamp type high pressure sealing jig according to the invention according to claim 4 has a plurality of spike-shaped protrusions formed on the clamp surface of the collet member according to any one of claims 1 to 3 to the heat transfer tube. It is characterized in that the direction of the tip of the shaped portion is adjusted so as to follow the pressing direction of the collet member toward the end of the collet member in the tube circumferential direction.

In the present invention, since a large number of spike-shaped projecting portions are formed on the clamping surface of the plurality of collet members to the heat transfer tube, the tube can be effectively bitten into the tube, and the jig slides. The amount can be kept small, and high-pressure sealing at both ends of the tube becomes possible without welding work, which greatly reduces the time and cost of pressure resistance tests and the like. In addition, it is excellent in safety because it has a structure that clamps with a larger force when it receives pressure. Furthermore, the size of the sealing jig can be easily miniaturized, and even if the pipe end is clamped from the outside for sealing, it can be mounted well without interfering with each other, and there is no leakage. It has the effect of being able to obtain ingredients. Further, by devising the sealing means, it is possible to minimize scratches on the ring-shaped squeeze packing.

FIG. 6 is a schematic cross-sectional view showing a high-pressure sealing jig according to an embodiment of the present invention in a completed state, where a is a side sectional view along the central axis of the heat transfer tube and b is a direction orthogonal to the central axis of the heat transfer tube. FIG. A is a cross-sectional view taken along the line AA, and FIG. It is a schematic perspective view before attaching the heat transfer tube end portion which shows the member structure of the high pressure sealing jig of FIG. 1, and partially includes a cross section. It is explanatory drawing which shows the structure of the collet member of the high pressure sealing jig of this invention, a figure is a perspective view, b figure is a sectional view, c figure is a front view, d figure is an enlarged view of the broken line part region of figure b. FIG. e is an enlarged view of the broken line portion region of FIG. C. It is a schematic perspective view which shows the state which the high pressure sealing jig of FIG. 1 is attached to each of a plurality of heat transfer tubes arranged in parallel in the horizontal direction in the body. It is a side sectional view for demonstrating the heat transfer tube end attachment process of the high pressure sealing jig of FIG. 1, and FIGS. It is a side sectional view for demonstrating the heat transfer tube end attachment process of the high pressure sealing jig of another Example, and FIGS. aa-c show the state of each process.

The present invention is a high-pressure sealing jig in which a plug having a flow path for introducing a high-pressure fluid from a high-pressure hose is attached to the end of a heat transfer tube of a multi-tube heat exchanger while sealing the end. A plurality of collet members that individually move in the radial direction of the heat transfer tube to clamp the outer peripheral surface of the heat transfer tube with respect to the end of the heat transfer tube, and slidable and transfer to the plurality of collet members from the outside. A sleeve member having a fitting hole formed around the heat pipe axis so as not to rotate relative to each other, a sealing means for liquid-tightly sealing the plug and the end of the heat transfer tube, and a connection connecting the sleeve member and the plug. It has a mechanism.

Further, the outer wall surface of the plurality of collet members in contact with the sleeve member forms a tapered surface that gradually decreases toward the center side of the heat transfer tube axial direction, and the inner wall surface of the fitting hole of the sleeve member is plurality. A tapered surface is formed that slidably abuts each other at the same inclination angle as the tapered surface of the collet member, and the plurality of collet members move toward the center of the heat transfer tube along the axial direction of the heat transfer tube with respect to the sleeve member. As a result, the distance between the individual parts is reduced, and the ends of the heat transfer tubes are tightened, and a large number of spike-shaped protrusions are formed on the clamping surfaces of the plurality of collet members to the heat transfer tubes. It is a method of clamping the pipe end from the outside, and it is possible to obtain a high-pressure sealing jig for the pipe end that does not leak even when a high pressure is applied.

The plurality of collet members of the present invention may be those that are clamped by two or more. If there are three or more collet members, the clamped pipes are evenly clamped from three or more directions, so that there is an advantage that high sealing performance can be obtained. Further, particularly if a pair of collet members clamp each other so as to face each other, a narrow sealing jig can be used, which is advantageous when the pitch between the heat transfer tubes of the multi-tube heat exchanger is narrow. ..

In the pair of collet members, the pair of collet members that individually move in the radial direction of the heat transfer tube to clamp the outer peripheral surface of the heat transfer tube with respect to the end of the heat transfer tube, and the pair of collet members can be slid from the outside. Moreover, it is provided with a sleeve member having a fitting hole formed around the heat transfer tube axis so as to be fitted so as not to rotate relative to each other, and a connecting mechanism for connecting the sleeve member and the plug, and is in contact with the sleeve member of a pair of collet members. The outer wall surface forms a tapered surface that gradually decreases toward the center side of the heat transfer tube axis, and the inner wall surface of the fitting hole of the sleeve member has the same inclination angle as the tapered surface of the pair of collet members. Tapered surfaces that slidably contact each other are formed, and the pair of collet members move toward the center of the heat pipe along the axial direction of the heat transfer pipe with respect to the sleeve member, thereby reducing the distance between the individual heat transfer pipes. A large number of spike-shaped projecting portions are formed on the clamp surface of the pair of collet members to the heat transfer tube.

In the outer clamp type high-pressure sealing jig provided with this pair of collet members, a pair of collet members that are fitted in a wedge shape between the outer peripheral surface of the pipe end and the tapered surface of the inner wall surface of the fitting hole of the sleeve member are used. It securely clamps the end of the pipe. Then, for example, when mounting a multi-tube heat exchanger on the end of a heat transfer tube during a pressure resistance test, the outer peripheral surfaces of the tube are clamped to the end of the tube so as to face each other in the diameter direction of one tube. Since there is only a pair of collet members, the thickness of the outer clamp type high-pressure sealing jig including the sleeve member for fitting and tightening the pair of collet members from the outside is large only in the clamping direction in the pipe diameter direction. Therefore, the thickness of the member can be kept small in the region around the pipe end where no other collet member exists, so that the outer clamp type high-pressure sealing jig can be miniaturized.

Specifically, if this region with a small member thickness is positioned between the heat transfer tubes arranged inside the fuselage and the external clamp type high pressure sealing jig is attached, the heat transfer tubes are clamped and sealed from the outside. Even if it is, it can be attached to the end of the heat transfer tube satisfactorily without interfering with each other, and the plug can be attached in a good sealed state, and the thickness of the member in the left-right direction (horizontal direction) can be reduced. Therefore, it is possible to support a multi-tube heat conductor in which more heat transfer tubes are arranged in parallel in the horizontal direction and the tube pitch between adjacent heat transfer tubes on the left and right is narrowed.

If the arrangement configuration of the heat transfer tubes of the multi-tube heat exchanger to be used is determined in advance, for example, the outer clamp type is used with respect to the pitch P between the central axes of the adjacent heat transfer tubes in the horizontal direction. The distance D from the center of the high-pressure sealing jig to the position where the maximum outer diameter is obtained in the horizontal direction may be 1/2 or less of the pitch P. Further, the outer shape of the outer clamp type high-pressure sealing jig is substantially rectangular in the cross-sectional shape in the direction orthogonal to the central axis of the heat transfer tube so that the outer shape of the sleeve member can be arranged in parallel efficiently. It is preferable to have it. Further, the contour of the fitting hole of the sleeve member and the outer shape of the pair of collet members are also configured such that the cross-sectional shape in the direction orthogonal to the central axis of the heat transfer tube is substantially rectangular, so that the pair of collet members can be used as the sleeve member. On the other hand, rotation around the central axis of the heat transfer tube is avoided, and a good tightening state with respect to the tube end can be maintained.

When the end of the heat transfer tube is tightened, a large number of spike-shaped projecting portions formed on the clamp surface of the collet member of the present invention generate sufficient surface pressure on the outer surface of the tube to bite into it. It suffices as long as it can hold the tightening position more reliably by the spike-shaped protruding portion. That is, since the tip bites into the outer peripheral surface of the pipe due to the spike-shaped protruding portion to prevent it from coming off, a force that pushes the outer clamp type high-pressure seal jig from the pipe end acts when introducing high-pressure water during the pressure resistance test. However, against this, a good pipe end clamped state by the collet member is maintained. The preferred spike-shaped projecting portion has a vertical cross section along the heat transfer tube axial direction, which is a tooth-shaped projecting portion having a pointed tip, and more preferably, the tips of a plurality of spike-shaped projecting portions. Examples thereof have an angle of 50 ° to 70 °.

Further, as the collet member is pressed toward the end in the circumferential direction of the pipe, the tip of the protruding portion is pressed in a direction different from the central axis of the pipe with respect to the pressing direction of the collet member. If the serration shape is such that the tip of the portion faces the central axis of the pipe, the blade at the end may not sufficiently bite or break, so the pressing direction of the collet member increases toward the end in the circumferential direction of the collet member. The tip of the projecting portion is adjusted so that the tip angle of the end is smaller than that of the center of the tube circumference, and the tip of the tip side portion is perpendicular to the pressing surface. By doing so, the tip bites more preferably into the outer surface of the pipe in the same direction as the pressing direction with respect to the pressing of the collet member. It should be noted that the vertical cross section of the spike-shaped projecting portion along the heat transfer tube axial direction allows the tips of the individual projecting portions to bite into the pressing direction of the collet member even if the serration shape is serrated.

In the present invention, since a large number of spike-shaped projecting portions are formed on the clamp surface of the plurality of collet members to the heat transfer tube, the tightening position can be reliably held. That is, even if a force that pushes the outer clamp type high-pressure sealing jig from the pipe end acts when introducing high-pressure water during the pressure resistance test, the spike-shaped protruding part of the collet member resists this and makes the pipe good. The end clamped state is maintained. Further, in order to prevent water leakage when introducing high-pressure water, it is possible to counter high-pressure water, which is a large pressure, by further devising the sealing means of the present invention.

The sealing means of the present invention may be any one that seals the plug and the end of the heat transfer tube in a liquid-tight manner. The liquid-tight seal may be any one that deforms and seals the outer peripheral surface of the heat transfer tube by the pressing force from the outside. Examples thereof include an O-ring alone that seals a plug and a heat transfer tube, a combination of an O-ring and a backup ring, and a ring-shaped squeeze packing. In particular, it was confirmed that the ring-shaped squeeze packing can withstand higher pressure than the liquid-tight seal by the O-ring.

FIG. 1 is a schematic cross-sectional view showing a high-pressure sealing jig according to an embodiment of the present invention in a completed state. FIG. 1A is a side sectional view along the direction of the central axis of the heat transfer tube, and FIG. 1B is orthogonal to the central axis of the heat transfer tube. FIG. AA is a cross-sectional view taken along the line A, and FIG. C is a cross-sectional view taken along the line BB in FIG. FIG. 2 is a schematic perspective view of the member configuration of the high-pressure sealing jig of FIG. 1 before mounting the end of the heat transfer tube, and partially includes a cross section. FIG. 3 is an explanatory view showing the configuration of a collet member of the high-pressure sealing jig of the present invention, where a is a perspective view, b is a sectional view, c is a front view, and d is a broken line region of FIG. The enlarged view and the figure e are enlarged views of the broken line portion region of the figure c.

FIG. 4 is a schematic perspective view showing a state in which the high-pressure sealing jig of FIG. 1 is attached to a plurality of heat transfer tubes arranged in parallel in the horizontal direction in the body. FIG. 5 is a side sectional view for explaining the process of attaching the end of the heat transfer tube of the high-pressure sealing jig of FIG. 1, and FIGS. A to c show the state of each process. FIG. 6 is a side sectional view for explaining a process of attaching the heat transfer tube end portion of the high-pressure sealing jig of another embodiment, and FIGS. A to c show states of each process.

As shown in FIGS. 1 to 5, the outer clamp type high pressure sealing jig 1 according to the present embodiment clamps the outer peripheral surfaces of the heat transfer pipe 2 so as to face each other in the diameter direction of one pipe. Collet members (10a, 10b), a sleeve member 15 having a fitting hole 16 formed in the pair of collet members so as to be slidable from the outside and non-rotatably around the heat transfer tube axis, and the sleeve. A connecting mechanism for connecting the member 15 and the plug 3 is provided.

The facing outer wall surfaces of the pair of collet members (10a, 10b) form a pair of tapered surfaces (11a, 11b) whose outer diameter gradually decreases toward the center side of the heat transfer tube along the axial direction. On the inner wall surface of the fitting hole 16 of the sleeve member 15, tapered surfaces (17a, 17b) that slidably contact each other at the same inclination angle as the tapered surfaces (11a, 11b) of the pair of collet members are formed. The pair of collet members (10a, 10b) move toward the center of the heat transfer tube along the axial direction of the heat transfer tube with respect to the sleeve member 15, so that the distance between them becomes smaller and the ends of the heat transfer tube 2 are tightened. Include.

Specifically, in the outer clamp type high pressure sealing jig 1, first, a heat transfer tube 2, that is, a rifle tube 2 having a plurality of spiral ribs on the inner surface is inserted between the heat transfer tubes 2, and the outer peripheral surface of the end thereof is rifleed. A pair of collet members (10a, 10b) that clamp the pipe 2 so as to face each other in the vertical diameter direction, and a fitting hole 16 that is slidably fitted to the pair of collet members (10a, 10b) from the outside are formed. The sleeve member 15 is provided. The outer shape of the pair of collet members (10a, 10b) is such that the upper and lower outer wall surfaces facing each other form a pair of tapered surfaces (11a, 11b) whose outer diameter gradually decreases toward the center side of the pipe, and the rifle. The cross-sectional shape in the direction orthogonal to the central axis of the pipe has a substantially rectangular shape with the four corners chamfered.

The inner peripheral shape of the fitting hole 16 of the corresponding sleeve member 15 has a substantially rectangular cross-sectional shape in the direction orthogonal to the central axis of the rifle tube 2 so as to follow the outer shape of the pair of collet members (10a, 10b). At the same time, the upper and lower inner wall surfaces are tapered surfaces (17a, 17b) that slidably abut against each other at the same inclination angle as the upper and lower tapered surfaces (11a, 11b) of the pair of collet members. As a result, since the pair of collet members (10a, 10b) and the fitting hole 16 have a substantially rectangular cross section, the relative rotation of both members around the central axis of the rifle tube is restricted, and the pair of collet members (10a, 10b). The tightening of the rifle tube 2 in 10b) becomes more stable.

Further, in this embodiment, as shown in FIG. 3, a large number of spike-shaped projecting portions 12 are formed on the clamp surface of the pair of collet members (10a, 10b) to the rifle tube 2. These protruding portions 12 form a serrated serration shape in which the vertical cross section of the rifle tube 2 along the axial direction has a continuous tooth-like shape with a sharp tip (FIG. 3d), and collet members (10a, 10b). The direction of the tip of the spike-shaped protruding portion is adjusted so as to follow the pressing direction of the collet members (10a, 10b) toward the end in the tube circumferential direction (FIG. 3e). Therefore, even if pressure is applied in the direction of pushing the outer clamp type high pressure sealing jig 1 back to the outside of the pipe during the pressure resistance test, the rifle pipe 2 is tightened by the effect of preventing the rifle pipe 2 from coming off due to the biting of the tips of the protruding portions 12. Is maintained more firmly. Further, the angle of the tip of the protruding portion 12 is adjusted to 50 ° to 70 ° so that it can easily bite into the outer peripheral surface of the rifle tube 2.

Further, on the inner peripheral surfaces of the pair of collet members (10a, 10b), a groove 13 is formed at the same position in the axial direction of the rifle along the circumferential direction, and a C-shaped retainer ring is formed in the groove 13. 14 is slidably stored. The retainer ring 14 connects the pair of collet members (10a, 10b) along the central axis direction of the rifle tube while responding to the change in the distance between the pair of collet members (10a, 10b) due to tightening. The movement can be integrated.

In the outer clamp type high pressure sealing jig 1, a cover member 18 having the same outer shape as the sleeve member 15 is screwed to the sleeve member 15 as a connecting mechanism for the plug 3 for further connecting the high pressure hose H. A through-hole-shaped female screw hole 19 is formed in the center of the cover member 18.

On the other hand, a connection portion with the high pressure hose H is provided at the outer end of the plug 3 provided with the flow path 33 into which the high pressure water from the high pressure hose H is introduced, and a rifle pipe 2 is provided at the central portion inside the plug 3. A cylindrical insertion portion 31 that fits on the outer periphery of the end portion, and a metal adapter ring 21 that presses the rear end portion of the collet member (10a, 10b) at the inner end portion. As shown in FIGS. 2 and 5, the cylindrical insertion portion 31 has a ring-shaped squeeze packing 23 made of urethane resin that presses and seals the outer peripheral surface of the rifle tube 2 by pressing from the outside of the plug 3, and the squeeze packing 23. A brass thruster ring 22 that reduces the rotation by tightening the plug 3 and an adapter ring 21 having an L-shaped cross section that transmits the pressing force due to the tightening of the plug 3 to the rear ends of the collet members (10a, 10b). It has been inserted.

The outer peripheral surface of the plug 3 is subjected to male screw processing 32 to be screwed into the female screw hole 19 of the cover member 18, and the plug 3 is screwed into the female screw hole 19 of the cover member 18 from one end side and tightened. , The adapter ring 21 connected to the sleeve member 15 and inserted into the cylindrical insertion portion 31 of the plug 3 presses the rear end portion of the collet member (10a, 10b), and a pair in the fitting hole 16 of the sleeve member 15. It is attached to the outer peripheral surface of the end portion of the rifle tube 2 that protrudes through the collet members (10a, 10b). The collet members (10a, 10b) are tightened to the rifle tube 2 by further tightening the plug 3, and the adapter ring 21 presses the ring-shaped squeeze packing 23 inside the cylindrical insertion portion 31 to press the rifle tube 2 Press-sealed against the outer peripheral surface.

To attach the outer clamp type high-pressure sealing jig 1 in the above configuration, first, as shown in FIG. 5A, a pair of collet members (10a, 10b) are arranged in the fitting hole 16 of the sleeve member 15, and the sleeve. The plug 3 is screwed to some extent into the female screw hole 19 of the cover member 18 screwed to the member 15 (not shown for simplification of the drawing) to integrate the constituent members. Then, the rifle tube 2 is inserted from between the pair of collet members (10a, 10b) until it penetrates the cover member 18, and the tube end portion is fitted into the inner circumference of the cylindrical insertion portion 31 of the plug 3 (FIG. 5 (FIG. 5). b)).

After that, by advancing the screwing of the plug 3 and moving it toward the center of the pipe along the axial direction of the heat transfer tube, the adapter ring 21 inserted into the cylindrical insertion portion 31 of the plug 3 is a pair of collet members (10a). , 10b) can be pressed to push the pair of collet members (10a, 10b) into the sleeve member 15 in the direction of tightening the pipe end, as shown in FIG. 5 (c). At the same time as the plug 3 is attached, the attachment of the outer clamp type high pressure sealing jig 1 is completed by tightening the pair of collet members (10a, 10b) to the pipe ends. At this time, the adapter ring 21 is pressed and sealed against the outer peripheral surface of the rifle tube 2 by pressing the ring-shaped squeeze packing 23 inside the cylindrical insertion portion 31.

In this embodiment, the outer shape of the outer clamp type high-pressure sealing jig 1, that is, the outer shape of the sleeve member 15 and the cover member 18 has a rectangular cross section with the vertical direction being the long side direction, and is a multi-tube heat exchanger. The distance D from the center of the outer clamp type high pressure sealing jig 1 to the position where the maximum outer diameter is obtained in the horizontal direction is set with respect to the pitch P between the central axes of the rifle tubes 2 adjacent to each other in the horizontal direction. , The pitch P can be set to 1/2 or less, and as shown in FIG. 4, adjacent outer clamp type high pressure sealing jigs 1 can be satisfactorily attached to a large number of rifle tubes 2 without interfering with each other. It became.

Further, the tightening position can be more reliably held by the large number of spike-shaped projecting portions 12 formed on the clamp surface of the collet members (10a, 10b) to the rifle tube 2. Further, as a sealing means for liquid-tightly sealing the plug and the end of the heat transfer tube, an adapter ring having a small diameter portion having an L-shaped cross section is provided in the cylindrical insertion portion 31 of the plug 3, and this small diameter portion is inserted into the plug. By pressing the collet member by tightening 3 and pressing and deforming the ring-shaped squeeze packing 23 inserted into the cylindrical insertion portion 31, it is possible to counter the large pressure of high-pressure water and prevent water leakage. can do. In this example, water leakage could be prevented even in a test with high pressure water of 50 MPa with a tightening torque of 200 Nm.

In the above embodiment, as a sealing means, a small diameter portion having an L-shaped cross section is inserted into the cylindrical insertion portion 31 of the plug 3, and the plug 3 is tightened to press the collet member and the cylindrical insertion portion 31. An adapter ring 21 that presses and deforms the ring-shaped squeeze packing 23 inserted in the is used, but if it is a pressure resistance test at a pressure of 20 MPa or less, even a sealing means using an O-ring can sufficiently cope with it. ..

For example, in the embodiment shown in FIG. 6, an O-ring 60 is used as the sealing means. Since the embodiment shown in FIG. 6 has the same configuration as the embodiment shown in FIGS. 1 to 5 except for the sealing means, the corresponding reference numerals are given by the same reference numerals. That is, the plug 3 provided with the flow path into which the high-pressure water is introduced has a cylindrical mounting portion 61 that fits on the outer periphery of the end portion of the rifle pipe 2 on the side opposite to the connection side with the high-pressure hose. An O-ring 60 is arranged on the inner peripheral surface of the cylindrical mounting portion 61. In this example, water leakage could be prevented even in a test with high pressure water of 19 MPa with a tightening torque of 100 Nm.

1 ... Outer clamp type high pressure sealing jig,
2 ... Rifle tube (heat transfer tube),
3 ... Plug,
10a, 10b ... Collet member,
11a, 11b ... Tapered surface,
12 ... protruding part,
13 ... groove,
14 ... Retaining,
15 ... Sleeve member,
16 ... Fitting hole,
17a, 17b ... Tapered surface,
18 ... Cover member,
19 ... Female screw hole,
21 ... Adapter ring,
22 ... Thrustering,
23 ... Ring-shaped squeeze packing,
31 ... Cylindrical insertion part,
32 ... Male thread processing,
33 ... Flow path,
60 ... O-ring,
61 ... Cylindrical mounting part,

Claims (4)

A high-pressure sealing jig in which a plug having a flow path for introducing a high-pressure fluid from a high-pressure hose is attached to the end of a heat transfer tube of a multi-tube heat exchanger while sealing this end.
A plurality of collet members that individually move in the radial direction of the heat transfer tube and clamp the outer peripheral surface of the heat transfer tube with respect to the end portion of the heat transfer tube.
A sleeve member having a fitting hole formed in the plurality of collet members so as to be slidable from the outside and to be fitted around the heat transfer tube axis so as to be relatively non-rotatable.
A sealing means for liquid-tightly sealing the plug and the end of the heat transfer tube,
A connecting mechanism for connecting the sleeve member and the plug is provided.
The connecting mechanism
It has a cover member having a through-hole-shaped female screw hole formed in the center fixed to the sleeve member, and a male screw process formed on the outer peripheral surface of the plug and screwed into the female screw hole.
With the ring-shaped squeeze packing that presses and seals the outer peripheral surface of the end portion of the heat transfer tube arranged between the rear end portion of the collet member and the end portion of the plug, the screw of the plug is advanced to advance the sleep. It connects the member and the plug,
The outer wall surface of the plurality of collet members in contact with the sleeve member forms a tapered surface that gradually decreases toward the center side of the heat transfer tube axial direction, and the inner wall surface of the fitting hole of the sleeve member. However, tapered surfaces that slidably abut each other at the same inclination angle as the tapered surfaces of the plurality of collet members are formed.
The plurality of collet members move toward the center of the heat transfer tube along the axial direction of the heat transfer tube with respect to the sleeve member, so that the distance between the plurality of collet members becomes smaller and the ends of the heat transfer tube are tightened.
An outer clamp type high-pressure sealing jig characterized in that a large number of spike-shaped projecting portions are formed on the clamp surface of the plurality of collet members to the heat transfer tube. A plurality of spike-shaped projecting portions formed on the clamp surface of the collet member to the heat transfer tube have a tooth-shaped projecting portion having a pointed tip in a vertical cross section along the heat transfer tube axial direction. The outer clamp type high-pressure sealing jig according to claim 1. The outer clamp type high voltage according to claim 2, wherein the tip angles of the plurality of spike-shaped projecting portions formed on the clamp surface of the collet member to the heat transfer tube are 50 ° to 70 °. Sealing jig. The direction of the tips of the plurality of spike-shaped projecting portions formed on the clamp surface of the collet member to the heat transfer tube is along the pressing direction of the collet member as it goes toward the end in the tube circumferential direction of the collet member. The outer clamp type high pressure sealing jig according to any one of claims 1 to 3, wherein the jig is adjusted to.

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