CN102601205A - Hydraulic bulging pipe end combination sealing device - Google Patents

Abstract

The invention relates to a hydraulic bulging pipe end combination sealing device, comprising a pressure head and a columned sealing slider arranged in the pressure head, one end of the sealing slider contacts the pipe ends, the part of the sealing slider contacting the pipe ends is a convex ring curve, the other one end of the sealing slider elastically contacts the pressure head. The hydraulic bulging pipe end combination sealing device can reduce an axial force for sealing the pipe ends, increase the bulging volume of the pipe blanks and reducing the thickness of the walls; the ends of the pipe blanks are processed to form an inner bevel and are repeatedly used for hydraulically bulging at two times.

Description

Hydraulic expanding pipe end combination sealing device

technical field

The invention relates to a hydraulic bulging pipe end combined sealing device.

Background technique

In the hydraulic bulging of tubes, it is a necessary condition to ensure the reliable sealing of the tube end. The traditional tube end sealing methods include flat seal, ring-shaped sharp knife seal and cone-shaped insert seal. Figure 1 is a schematic diagram of a flat seal. The end plane of the punch directly bears against the ring end of the pipe, and both ends of the pipe are squeezed 2 to 3mm at the same time to make it sealed. It is suitable for medium bulging pressure and flat pipe ends. Condition. Figure 2 is a schematic diagram of the ring-shaped sharp knife seal. The end face of the punch is processed into a 1.5mm high ring-shaped sharp knife, and the sharp knife is inserted into the metal of the end surface of the pipe, and the sharp knife and the plane of the punch are jointly sealed. It is suitable for thick-walled pipes and high pressure. place. Fig. 3 is a schematic diagram of a frustum plug-in seal. The front of the punch is processed into a frustum with a straight section. When sealing the pipe mouth, the frustum is inserted into the tube blank, so that the pipe wall is sandwiched between the frustum and the mold, and then by The flat surface of the root of the cone seals the pipe end, which is suitable for the bulging of thin-walled pipes, and requires the finishing of the pipe end plane and inner hole.

The above three common pipe end sealing methods all require finishing the end face of the tube blank, and the sealing is achieved by plastically deforming the tube end as a whole, which requires a large axial force and is suitable for occasions where the bulge of the tube blank is not large.

Large-scale variable cross-section straight-axis special-shaped pipes, such as automobile axle housings, have large geometric dimensions, large cross-sectional dimension differences, and complex shapes. When using the steel pipe expansion and compression forming method to manufacture such parts, select a certain specification of seamless steel pipe, first reduce the diameter of its two ends, and then perform hydraulic bulging once or twice in the middle to obtain a preformed tube blank, and finally press and form it to obtain parts. When the tube blank is hydraulically bulging, the above three sealing methods are selected, and the axial thrust cannot effectively act on the large bulging area in the middle of the tube blank, and the wall thickness of the tube blank in the middle is greatly reduced, which is easy to swell. In addition, if the tube blank needs to be hydraulically bulged twice after the diameter is reduced, the end of the tube blank after the first hydraulic bulging needs to be processed again, otherwise it is difficult to ensure reliable sealing of the tube end.

Contents of the invention

The technical problem to be solved by the present invention is: to provide a pipe end seal that requires small axial force, can effectively act on the axial thrust in the middle of the tube blank, has a large amount of bulging, and a small amount of wall thickness reduction. Reusable hydraulic bulging pipe end combination seal device in hydraulic bulging.

In order to solve the above problems, the technical solution adopted in the present invention is: hydraulic bulging pipe end combined sealing device, including a pressure head, a cylindrical sealing slider arranged in the pressure head, one end of the sealing slider is connected to the pipe end The contact part between the sealing slider and the pipe end is a convex circular surface, and the other end of the sealing slider is in elastic contact with the pressure head.

The sealing slider is arranged in the pressure head through the sealing pressure block, and the inside of the pressure head is provided with a cylindrical hole, and the sealing slider is arranged in the cylindrical hole with a gap fit, and the outer end of the sealing slider is provided with a sealing pressure block. The outer end of the pressure block is provided with a flange, the flange is connected with the pressure head through a screw, the inner side of the cylindrical hole is provided with a spring seat, the inner end of the sealing slider is provided with an end cover, and a spring is provided between the end cover and the spring seat .

A slider hole is arranged in the sealing slider, a pressure head channel is arranged in the pressure head, a pipe joint is arranged at one end of the pressure head channel, the other end of the pressure head channel is connected with one end of the slider hole, and the slider hole The other end communicates with the inner hole of the tube blank.

An elastic combined sealing ring is arranged between the contact surface of the sealing slider and the pressure head.

The beneficial effects of the present invention are:

1. The sealing of the pipe end requires a small axial force, a large amount of bulging of the tube blank, and a small amount of wall thickness reduction.

2. The end face of the tube blank only needs to be processed with inner chamfers, and it can be reused in two hydraulic bulges.

Description of drawings

Fig. 1 is a schematic diagram of the flat seal described in the background art.

Fig. 2 is a schematic diagram of the annular sharp knife seal described in the background art.

Fig. 3 is a schematic diagram of the frustum-cone plug-in seal described in the background art.

Fig. 4 is a schematic diagram of a diameter-reduced tube blank according to an embodiment of the present invention.

Fig. 5 is a schematic diagram of a tube blank after hydraulic bulging according to an embodiment of the present invention.

Fig. 6 is a schematic structural view of a sliding hydraulic bulging mold according to an embodiment of the present invention.

Fig. 7 is a schematic structural diagram of a combined sealing device according to an embodiment of the present invention.

Fig. 8 is a schematic structural diagram of a sealing slider in a combined sealing device according to an embodiment of the present invention.

Fig. 9 is a schematic structural view of the sealing compact in the combined sealing device according to the embodiment of the present invention.

In the figure: 1. Left sealing device, 2. Left sliding module, 3. Upper mold guide block, 4. Upper template, 5. Upper fixed module, 6. Right sliding module, 7. Right sealing device, 8. Lower template, 9. Lower mold guide block, 10. Lower fixed module, 11. Tube blank, 12. Indenter, 121. Indenter channel, 13. Pipe joint, 14. Spring seat, 15. Spring, 16. End cover, 17. Elastic combined sealing ring, 18, sealing slider, 181, threaded hole, 19, sealing pressing block, 20, screw, 21, fixing screw, 22, spring limit block.

Detailed ways

The hydraulic bulging pipe end combined sealing device of the present invention will be further described in detail through specific embodiments below.

Fig. 4 is a schematic diagram of the reduced-diameter tube blank according to the embodiment of the present invention. The tube blank has a length of 1487 mm, an outer diameter of the middle part of 180 mm, a length of 366.5 mm of the straight arms on both sides, an outer diameter of the end part of 146 mm, a wall thickness of 10 mm, and an end processing of 1× 45° internal chamfer.

Fig. 5 is a schematic diagram of the tube blank after hydraulic bulging according to the embodiment of the present invention. The tube blank has a length of 1347 mm, the outer diameter of the end part is still 146 mm, and the outer diameter of the middle part is changed to 260 mm.

Fig. 6 is a schematic structural view of a sliding hydraulic bulging mold according to an embodiment of the present invention. The mold body consists of left sealing device 1, left sliding module 2, upper mold guide block 3, upper template 4, upper fixed module 5, right sliding module 6, right sealing device 7, lower template 8, lower mold guide block 9, lower fixed The module consists of 10. The left sliding module 2 and the right sliding module 6 slide in the cavity formed by the upper mold guide block 3 and the lower mold guide block 9 . The upper mold guide block 3 is connected with the upper template 4 , and the lower mold guide block 9 is connected with the lower template 8 . The two ends of the tube blank 11 are in contact with the left and right sealing devices, and at the same time, the tapered transition part of the tube blank 11 is in contact with the cavities of the left and right sliding modules of the mould.

As shown in Figure 7, the combined sealing device for hydraulically expanding pipe ends according to the present invention includes a pressure head 12, a cylindrical sealing slider 18 arranged in the pressure head 12, and one end of the sealing slider 18 is connected to the pipe end. The ends 11 are in contact with each other, and the contact part between the sealing slider 18 and the pipe end is a convex circular surface, and the other end of the sealing slider 18 is in elastic contact with the pressure head 12 . A schematic diagram of the structure of the sealing slider 18 is shown in FIG. 8 . The outer side of the sealing slider 18 is a cylindrical surface with a diameter of Φ240mm and an M16 threaded hole 181 in the center. There are two steps at the left end of the sealing slider 18. The large step is equipped with an elastic combined sealing ring with a diameter of Φ222.8mm and a length of 14.1mm; the small step is covered with an end cover with a diameter of Φ100mm and a length of 11mm. The right end of the sealing slider has a convex curved surface, which is in contact with the inner chamfer of the end surface of the tube blank to achieve sealing. The radius of curvature of the surface is R ₁ =100mm, and its tail end is inserted into the tube blank. The diameter of the right end is Φ117mm.

As a preferred mode, the sealing slider 18 is arranged in the ram 12 through a sealing briquetting block, a cylindrical hole is arranged inside the ram 12, and the sealing slider 18 is arranged in the cylindrical hole with a clearance fit, and the sealing slider 18 The outer end is provided with a sealing briquetting block 19, and the outer end of the sealing briquetting block 19 is provided with a flange. An end cover 16 is provided, and springs 15 are arranged between the end cover 16 and the spring seat 14 , the springs 15 are uniformly distributed along the circumferential direction, and the position of each spring 15 is limited by a spring stopper 22 installed on the spring seat 14 . The left end of the spring 15 leans against the spring seat 14, and the right end presses on the end cover 16. The pre-tightening force during assembly acts on the sealing slider 18 through the end cover 16 to ensure the sealing of the end of the tube blank. The above-mentioned connection structure between the sealing slider 18 and the pressure head 12 can have various structural forms, which are not limited to the above-mentioned structures, and all belong to the protection category of the present invention. The structure of the sealing pressing block 19 is shown in FIG. 9 . The sealing briquetting block 19 is a stepped shaft with a hole, and the left end cylindrical surface transition fits into the cylindrical hole of the pressure head 12, and the left end surface limits the position of the right end of the sealing slider 18. The diameter of the cylindrical surface is Φ240mm and the length is 60mm. Sealing briquetting 19 rear ends have flange, and its diameter is Φ 289.5mm, length 30mm, has stepped hole and the threaded hole that is used for dismounting usefulness on the flange. The inner cavity of the sealing briquetting block 19 is a cylindrical hole with a diameter of Φ145.8mm, which is 0.2mm smaller than the outer diameter of the end of the tube blank after the diameter is reduced.

The pressure head 12 is provided with a pressure head channel 121, and one end of the pressure head channel 121 is provided with a pipe joint 13, and the other end of the pressure head channel 121 is connected with one end of the threaded hole 181, and the other end of the threaded hole 181 is connected with the pipe. The inner holes of the blank 11 are connected.

An elastic combined sealing ring 17 is arranged between the contact surface of the sealing slider 18 and the pressure head 12 . The elastic combination sealing ring 17 is made up of an O-shaped sealing ring and a reinforcing ring, and is installed on the large step of the sealing slider 18. The right end of the elastic combined sealing ring leans against the shoulder of the large step of the seal slider, and its left end is fixed by the end cover 16. The end cap 16 is sleeved on the small step of the sealing slider 18 , positioned by a cylindrical surface and connected to the sealing slider 18 by a fixing screw 21 for fixing the elastic combined sealing ring 17 .

When the above hydraulic bulging pipe end combination sealing device is in use, it is required to process the inner chamfer of 45° at the end of the sealed pipe blank. The sealing slider 18 in the combined sealing device of the embodiment of the present invention is clearance-fitted in the cylindrical hole of the pressure head 12, and can slide in the cylindrical hole of the pressure head. The pre-tightening force of the spring 15 acts on the sealing slider 18 to ensure the sealing of the end of the tube blank; when the length of the straight arms on both sides of the reduced diameter tube blank is slightly greater than the required value of 366.5mm, the sealing slider 18 slides outward , The spring 15 is further compressed to compensate for the length change of the tube blank.

The above-mentioned embodiment only illustrates the principle of the present invention and its effect, and the embodiment of partial use, but is not intended to limit the present invention; It should be pointed out that for those of ordinary skill in the art, without departing from the Under the premise of creating ideas, some modifications and improvements can also be made, which all belong to the protection scope of the present invention.

Claims (4)

1. Hydraulic bulging pipe end combined sealing device, comprising a pressure head, a cylindrical sealing slider arranged in the pressure head, characterized in that: one end of the sealing slider is in conflict with the pipe end, and the sealing slider is in contact with the pipe end The contact part of the pipe end is a convex circular surface, and the other end of the sealing slider is in elastic contact with the pressure head. 2. The hydraulic bulging pipe end combination sealing device according to claim 1, characterized in that: the sealing slider is arranged in the pressure head through the sealing pressure block, and the inside of the pressure head is provided with a cylindrical hole, and the sealing slider The gap fit is arranged in the cylindrical hole, and the outer end of the sealing slider is provided with a sealing pressure block, the outer end of the sealing pressure block is provided with a flange, the flange is connected with the pressure head through a screw, and the inner side of the cylindrical hole is provided with a spring seat , the inner end of the sealing slider is provided with an end cover, and a spring is provided between the end cover and the spring seat. 3. The hydraulic bulging pipe end combination sealing device according to claim 1 or 2, characterized in that: the sealing slider is provided with a slider hole, the pressure head is provided with a pressure head channel, and the pressure head channel One end is provided with a pipe joint, the other end of the pressure head channel is connected with one end of the slider hole, and the other end of the slider hole is connected with the inner hole of the tube blank. 4. The hydraulic bulging pipe end combined sealing device according to claim 1 or 2, characterized in that: an elastic combined sealing ring is arranged between the contact surface of the sealing slider and the pressure head.

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