Method for improving steel pipe chamfering groove truncated edge non-uniformity and groove corrugation defect

Abstract

The invention discloses a method for improving the defects of uneven truncated edge and corrugation of a chamfered groove of a steel pipe, and belongs to the technical field of metallurgical pipe production. The method specifically comprises the steps that a pneumatic power source and a hydraulic power source are used for end face cutting, switching is conducted according to the diameter and the thickness of a pipe, the pneumatic power source is adopted for the steel pipe with the diameter larger than 325 mm and the thickness smaller than 12.5 mm, and the hydraulic power source is adopted for other steel pipes; the arc-shaped clamp is used for clamping and fixing the steel pipe, the contact area of the clamp and the steel pipe is increased, and the defect that the chamfering end face is uneven due to deformation of the steel pipe caused by too large clamping force is avoided. The invention aims to provide the method for improving the truncated edge non-uniformity and the groove corrugation defect of the steel pipe chamfering groove, so that the truncated edge non-uniformity and the groove corrugation defect of the steel pipe chamfering groove are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of metallurgical pipe production, and particularly relates to a method for improving the uneven root face and groove ripple defects of the chamfered groove of steel pipes. Background Art

[0002] With the continuous increase in the development intensity of oil and natural gas in China, the market demand for thick-walled steel pipes for welding is increasing. Moreover, with the continuous improvement of China's steel pipe production capacity, China's steel pipe export business is also

[0003] rapidly expanding. To produce high-quality and high-value-added steel pipes, a chamfering machine must be configured in the finishing section of the steel pipe production line to deeply process the produced steel pipes to meet market requirements.

[0004] The chamfering of the steel pipe end face is an important process for the welding forming of steel pipes, and the chamfering machine is the most basic equipment in the chamfering process of steel pipes. Good groove quality is the guarantee of the welding process quality. The present invention can effectively improve the groove quality and has good application prospects in the market.

[0005] The technical problem to be solved by the present invention is to provide a method for improving the uneven root face and groove ripple defects of the chamfered groove of steel pipes. With the continuous application of large-diameter thin-walled pipes, in order to expand the product coverage rate, the production line design has a large margin. When chamfering large-diameter thin-walled seamless steel pipes, it is extremely easy to have the problem of unstable clamping during the production process due to the difficulty in setting the clamping force. Unstable clamping will cause the pipe fittings to shake during the groove cutting process, resulting in groove ripple defects, and even cause tool damage. Excessive clamping force causes the pipe fittings to deform, and uneven root face appears after chamfering the pipe fittings. Defects such as uneven chamfered end faces are shown in Figure 1 and bring inconvenience to the subsequent welding. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for improving the uneven root face and groove ripple defects of the chamfered groove of steel pipes, and to improve the uneven root face and groove ripple defects of the chamfered groove of steel pipes.

[0007] To solve the above technical problems, the present invention adopts the following technical solutions:

[0008] A method for improving the uneven root face and groove ripple defects of the chamfered groove of steel pipes according to the present invention includes:

[0009] Using two power sources of pneumatic and hydraulic for end face cutting, and switching according to the diameter and thickness of the pipe material. For steel pipes with a diameter greater than 325 mm and a thickness less than 12.5 mm, a pneumatic power source is used, and the rest use a hydraulic power source;

[0010] An arc-shaped clamp is used to clamp and fix the steel pipe to increase the contact area between the clamp and the steel pipe, avoiding deformation of the steel pipe caused by excessive clamping force and resulting in uneven chamfered end faces.

[0011] Furthermore, arc-shaped clamps of different specifications are designed according to the specifications of the pipes.

[0012] Furthermore, the arc-shaped fixture is fixedly mounted on the chamfering machine base.

[0013] Furthermore, the arc-shaped clamp is fixed by fixing bolts.

[0014] Furthermore, during the production process, the steel pipe is transported to the chamfering machine via a transport roller.

[0015] Furthermore, after accurate positioning, the arc-shaped fixture fixes the end of the steel pipe and then performs end face cutting.

[0016] Furthermore, the arc-shaped clamp is fixed by two relatively arranged fixing plates through a screw thread connection, and the distance between the two fixing plates can be adjusted by rotating the screw to adjust the degree of clamping of the steel pipe by the arc-shaped clamp.

[0017] Furthermore, the arc-shaped clamp includes two symmetrically arranged semi-arc clamps, and the ends of the two semi-arc clamps facing away from the arc surface are rotatably fixed with a fixed shaft through bearings, and the other end of the fixed shaft is fixed with a first fixed plate, and the fixed shaft is also movably sleeved with a second fixed plate, and the first fixed plate is provided with a plurality of through holes or threaded holes, and the second fixed plate is provided with a plurality of threaded holes corresponding to the through holes or threaded holes on the first fixed plate, and the bottom of the second fixed plate is fixedly set on the chamfering machine base, and a plurality of bolts pass through the through holes or threaded holes on the first fixed plate in sequence and then continue to pass through the corresponding plurality of threaded holes on the second fixed plate to realize adjustable fixation of the arc-shaped clamp, and rotating and adjusting the plurality of bolts can drive the two semi-arc clamps to move closer or farther away to adjust the clamping degree of the steel pipe.

[0018] Compared with the prior art, the present invention has the following beneficial technical effects:

[0019] The technical problem to be solved by the present invention is to provide a method for improving the uneven blunt edge and groove corrugation defects of the chamfered groove of steel pipes, overcoming the difficult problem that "with the continuous application of large-diameter thin-walled pipes, steel has a large production line design margin in order to expand product coverage. When chamfering large-diameter thin-walled seamless steel pipes, it is very easy to have unstable clamping problems in the production process due to the difficulty in setting the clamping force. Unstable clamping will cause the pipe fittings to shake during the groove cutting process, resulting in groove corrugation defects, and even damage the tool." BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] Figure 1 It is a photo of uneven chamfered end faces;

[0022] Figure 2 It is a schematic diagram of an arc-shaped clamp;

[0023] Figure 3 It is a groove diagram after improvement. Specific embodiments

[0024] A method for improving the unevenness of the root face and the groove ripple defects of the chamfered groove of steel pipes, comprising:

[0025] 1. When cutting the end face, select the fixture power source according to the steel pipe specifications. For steel pipes with a diameter greater than 340 mm and a thickness less than 10 mm, use a pneumatic power source, and for the rest, use a hydraulic power source.

[0026] 2. Design and machine an arc-shaped fixture as Figure 2 shown. The arc-shaped fixture can effectively increase the contact area between the fixture and the pipe fitting, make the force on the pipe fitting more uniform, and avoid the generation of uneven root face defects caused by excessive clamping force on the pipe fitting, resulting in deformation.

[0027] Design different clamps according to the pipe material specifications, install the clamps on the base of the chamfering machine and fix them with fixing bolts. During the production process, transport the steel pipe to the chamfering machine through the conveying roller table. After accurate positioning, the clamp fixes the pipe end of the steel pipe and then performs end face cutting. After cutting, the root face of the steel pipe groove is uniform, as shown in Figure 3 .

[0028] In one embodiment, the arc-shaped fixture is fixed by screw-thread connection of two oppositely arranged fixing plates. By rotating the screw, the distance between the two fixing plates can be adjusted, thereby realizing the adjustment of the clamping degree of the arc-shaped fixture on the steel pipe. Specifically:

[0029] The two fixing plates are fixedly mounted on the first fixing plate, the other end of the fixing plate being movably mounted on the second fixing plate (that is, the fixing plate can move relative to the second fixing plate along the axial direction). The two fixing plates are provided with a plurality of through holes or threaded holes, and the second fixing plate is provided with a plurality of threaded holes corresponding to the through holes or threaded holes on the first fixing plate. The bottom of the second fixing plate is fixedly mounted on the base of the chamfering machine, and a plurality of bolts are sequentially passed through the through holes or threaded holes on the first fixing plate and then continue to pass through the plurality of threaded holes corresponding to the second fixing plate to achieve adjustable fixation of the arc-shaped clamp. Rotating and adjusting the plurality of bolts can drive the fixing shaft to move closer to the clamping side, thereby driving the two semi-arc clamps to move closer to each other to achieve adjustment of the clamping degree of the steel pipe, and vice versa operation can drive the two semi-arc clamps to move away from each other.

[0030] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for improving the uneven root face and groove ripple defects of the bevel of steel pipes, characterized in that: Including: Use both pneumatic and hydraulic power sources for end face cutting, and switch according to the diameter and thickness of the pipe. For steel pipes with a diameter greater than 325 mm and a thickness less than 12.5 mm, a pneumatic power source is used, and the rest use a hydraulic power source; Adopt an arc-shaped fixture to clamp and fix the steel pipe, increase the contact area between the fixture and the steel pipe, and avoid defects such as uneven chamfered end faces caused by deformation of the steel pipe due to excessive clamping force.

2. The method for improving the uneven root face and groove ripple defects of the chamfered bevel of steel pipes according to claim 1, characterized in that: Design arc-shaped fixtures of different specifications according to the pipe specifications.

3. The method for improving the uneven root face and groove ripple defects of the chamfered bevel of steel pipes according to claim 1, characterized in that: The arc-shaped fixture is fixedly installed on the chamfering machine base.

4. The method for improving the uneven root face and groove ripple defects of the chamfered bevel of steel pipes according to claim 1, characterized in that: The arc-shaped fixture is fixed by fixing bolts.

5. The method for improving the uneven root face and groove ripple defects of the beveled pipe end according to claim 1, characterized in that: During the production process, the steel pipe is transported to the chamfering machine through the conveying roller path.

6. The method for improving the uneven root face and groove ripple defects of the beveled edge of steel pipes according to claim 5, characterized in that: After accurate positioning, the arc-shaped fixture fixes the pipe end of the steel pipe and then performs end face cutting.

7. The method for improving the uneven root face and groove ripple defects of the bevel of steel pipes according to claim 1, characterized in that: The arc-shaped fixture is fixed by screw thread connection of two oppositely arranged fixing plates through a screw. By rotating the screw, the distance between the two fixing plates can be adjusted, thereby realizing the adjustment of the clamping degree of the arc-shaped fixture on the steel pipe.

8. The method for improving the uneven root face and groove ripple defects of the chamfered bevel of steel pipes according to claim 7, characterized in that: The arc-shaped fixture includes two symmetrically arranged semi-circular clamps. At the ends of the two semi-circular clamps facing away from the arc surface, a fixed shaft is rotatably fixed through a bearing. The other end of the fixed shaft is fixed with a first fixing plate. A second fixing plate is also movably sleeved on the fixed shaft. A plurality of through holes or threaded holes are provided on the first fixing plate. A plurality of threaded holes corresponding to the through holes or threaded holes on the first fixing plate are provided on the second fixing plate. The bottom of the second fixing plate is fixedly arranged on the chamfering machine base. By sequentially passing a plurality of bolts through the through holes or threaded holes on the first fixing plate and then through the corresponding plurality of threaded holes on the second fixing plate, the adjustable fixing of the arc-shaped fixture can be realized. By rotating and adjusting the plurality of bolts, the two semi-circular clamps can be driven to approach or move away from each other to realize the adjustment of the clamping degree of the steel pipe.

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