CN110802364A - Device for generating residual compressive stress of tubular welded joint - Google Patents
Device for generating residual compressive stress of tubular welded joint Download PDFInfo
- Publication number
- CN110802364A CN110802364A CN201911204889.4A CN201911204889A CN110802364A CN 110802364 A CN110802364 A CN 110802364A CN 201911204889 A CN201911204889 A CN 201911204889A CN 110802364 A CN110802364 A CN 110802364A
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- CN
- China
- Prior art keywords
- compressive stress
- residual compressive
- welded joint
- branch pipe
- connecting rod
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K37/00—Auxiliary devices or processes, not specially adapted to a procedure covered by only one of the preceding main groups
- B23K37/04—Auxiliary devices or processes, not specially adapted to a procedure covered by only one of the preceding main groups for holding or positioning work
- B23K37/053—Auxiliary devices or processes, not specially adapted to a procedure covered by only one of the preceding main groups for holding or positioning work aligning cylindrical work; Clamping devices therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K37/00—Auxiliary devices or processes, not specially adapted to a procedure covered by only one of the preceding main groups
Abstract
The invention discloses a device for generating residual compressive stress of a welded joint of intersecting pipes, which comprises a main pipe and a branch pipe which are welded into a whole and are vertically arranged, wherein the main pipe is sleeved with four fixing ring clamps, the four fixing ring clamps are symmetrically arranged at two sides of the branch pipe, the fixing ring clamps at two sides are vertically connected with telescopic rod structures, the two fixing ring clamps in the middle are vertically connected with a vertical supporting rod, the branch pipe is provided with a four-jaw chuck, lever parts are connected between the four-jaw chuck and the upper ends of the telescopic rod structures at two sides, and the upper ends of the vertical supporting rods are connected with corresponding lever parts to form a lever structure; when the main pipe and the branch pipe are welded, the telescopic rod structure is contracted, and the lever piece is lifted upwards to pull the four-jaw chuck to generate welding tension, so that residual compressive stress after welding is formed. The invention improves the fatigue strength of the welding joint, reduces the deformation of the welding joint and can effectively reduce the generation of welding cold cracks.
Description
Technical Field
The invention belongs to the technical field of controlling welding deformation and improving welding quality, and particularly relates to a device for improving fatigue strength, corrosion resistance and crack resistance of a welding joint and reducing residual compressive stress of the welding joint of an intersecting pipe generated by deformation of the welding joint.
Background
Welding is used as a common connection mode of metal materials, the types and the application of the welding are very wide, and pipes or devices are connected in a welding mode because the welding has good air tightness; however, errors in the welding process and in the welding parameters, preparation before welding, etc. may result in the welded area not reaching the desired target. The pipe fitting is widely applied to the fields of nuclear power plants, chemical industry, petroleum and natural gas transportation and the like. At present, the welding process of an intersecting line formed by connecting two pipe fittings cannot be ensured due to high labor intensity of workers, severe working environment and poor welding quality. It is considered to design a means for generating residual compressive stress of a welded joint of intersecting pipes to improve the welding quality.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a device for improving the fatigue strength, the corrosion resistance and the crack resistance of a welding joint and reducing the deformation of the welding joint to generate the residual compressive stress of the welding joint of the intersecting pipe.
The technical scheme adopted by the invention is as follows:
a device for generating residual compressive stress of a welded joint of intersecting pipes is characterized in that: the four-jaw telescopic pipe comprises a main pipe and a branch pipe which are welded into a whole and are vertically arranged, wherein four fixing ring clamps are sleeved on the main pipe and symmetrically arranged at two sides of the branch pipe, telescopic rod structures are vertically connected to the fixing ring clamps at two sides, a vertical supporting rod is vertically connected to the two fixing ring clamps in the middle, a four-jaw chuck is mounted on the branch pipe, lever members are connected between the four-jaw chuck and the upper ends of the telescopic rod structures at two sides, and the upper ends of the vertical supporting rods are connected with the corresponding lever members to form a lever structure; when the main pipe and the branch pipe are welded, the telescopic rod structure is contracted, and the lever piece is lifted upwards to pull the four-jaw chuck to generate welding tension, so that residual compressive stress after welding is formed. When the main pipe and the branch pipe are welded, the telescopic rod structure and the lever structure generate a welding pulling force to form residual compressive stress after welding, so that the fatigue strength of a welding joint is improved, the deformation of the welding joint is reduced, and the generation of welding cold cracks can be effectively reduced.
Further, the telescopic rod structure comprises a first vertical connecting rod, a through hole sleeve and a second vertical connecting rod, the first end of the first vertical connecting rod is in threaded connection with the fixing ring clamp, the second end of the first vertical connecting rod is in threaded connection with the first end of the second vertical connecting rod, the second end of the second vertical connecting rod is hinged to the lever piece, and the telescopic rod structure can be shortened or extended after the through hole sleeve rotates.
Furthermore, internal threads are arranged at two ends of the through hole sleeve, and a hexagonal protrusion used for screwing rotation is arranged in the middle of the through hole sleeve.
Furthermore, a load sensor for detecting tensile force is arranged on the second vertical connecting rod, and the tensile force of the telescopic rod structures on the two sides is ensured to be consistent through the load sensor.
Further, the first end of vertical support rod and solid fixed ring anchor clamps threaded connection, its second end is equipped with the hinge seat, pass through the bolt connection between hinge seat and the lever spare. The hinge seat is used as a connecting device, dead points can appear during working, and the phenomenon of instability of the rod piece in the force transmission process is avoided.
Further, the hinge seat comprises an upper hinge and a lower hinge seat, and the upper hinge and the lower hinge seat are in medium clearance fit.
Further, the fixed ring clamp comprises two half ring clamps, two ends of each half ring clamp are connected through a hexagon bolt, and a threaded hole used for being connected with the first vertical connecting rod or the vertical supporting rod is formed in the middle of one half ring clamp.
Furthermore, two symmetrically distributed fixing threaded holes are formed in the two ends of each semi-ring clamp and are connected with the hexagon bolts.
Further, four-jaw chuck includes latch, hexagon socket head cap screw reforms transform two fixed points of bolt and symmetric distribution, four-jaw chuck and branch pipe are through four latch transition coordination, there is tooth structure latch bottom, and it is fixed with hexagon socket head cap screw reforms transform the bolt meshing, fixed point and lever spare hinged joint.
Furthermore, the main pipe and the fixing ring clamp, the branch pipe and the four-jaw chuck are connected in a transition fit mode.
The invention has the beneficial effects that: downward pressure can be applied to the welded joint obtained after welding, so that the fatigue strength and the corrosion resistance and the crack resistance of the joint are improved, and the deformation of the joint is reduced. And the welded workpieces can be fixed, so that the workload of workers is reduced, and the welding operation can be performed by the workers with great concentration. In addition, the device is easy to operate, simple in structure, flexible and changeable, the installation position can be adjusted according to the size of the pipe fitting, special training of constructors is not needed, and time and personnel training cost are saved.
Drawings
Fig. 1 is a schematic view of the overall structure of the present invention.
Fig. 2 is a schematic structural view of the telescopic rod structure of the present invention.
Fig. 3 is a schematic view of the structure of the four-jaw chuck of the present invention.
Fig. 4 is a schematic structural view of the retaining ring clamp of the present invention.
Fig. 5 is a schematic structural view of the hinge base of the present invention.
Fig. 6 is a schematic structural view of the hexagon socket head cap thread modified bolt of the invention.
In the figure: 1-dry pipe; 2-fixing the ring clamp; 3-a first vertical connecting rod; 4-a through-hole sleeve; 5-a load cell; 6-a lever member; 7-vertical support bars; 8-a hinge mount; 9-a four-jaw chuck; 10-latch; 11-modifying the bolt by using an inner hexagonal jackscrew; 12-a fixed point; 13-welding seam; 14-a manifold; 15-hexagon bolts; 16-a second vertical connecting rod.
Detailed Description
The present invention is further illustrated by the following examples, which are not intended to limit the invention to these embodiments. It will be appreciated by those skilled in the art that the present invention encompasses all alternatives, modifications and equivalents as may be included within the scope of the claims.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be considered as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "a plurality" means two or more unless explicitly defined otherwise.
In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.
Referring to fig. 1, the embodiment provides a device for generating residual compressive stress of a welded joint of intersecting pipes, which comprises a main pipe 1 and a branch pipe 14 which are welded into a whole and are vertically arranged, wherein four fixing ring clamps 2 are sleeved on the main pipe 1, the four fixing ring clamps 2 are symmetrically arranged on two sides of the branch pipe 14, telescopic rod structures are vertically connected to the fixing ring clamps 2 on two sides, a vertical support rod 7 is vertically connected to the two fixing ring clamps 2 in the middle, a four-jaw chuck 9 is mounted on the branch pipe 14, a lever member 6 is connected between the four-jaw chuck 9 and the upper ends of the telescopic rod structures on two sides, and the upper end of the vertical support rod 7 is connected with the corresponding lever member 6 to form a lever structure; when the main pipe 1 and the branch pipe 14 are welded, the telescopic rod structure is contracted, and the lever member 6 is lifted upwards to pull the four-jaw chuck 9 to generate welding pulling force, so that residual compressive stress after welding is formed. When the main pipe 1 and the branch pipe 14 are welded, the telescopic rod structure and the lever structure generate a welding pulling force to form residual compressive stress after welding, so that the fatigue strength of a welding joint is improved, the deformation of the welding joint is reduced, and the generation of welding cold cracks can be effectively reduced.
Referring to fig. 2, the telescopic rod structure of the present embodiment includes a first vertical connecting rod 3, a through hole casing 4, and a second vertical connecting rod 16, where both ends of the first vertical connecting rod 3 are both of an external thread structure, and one end of the second vertical connecting rod 16 is a hinge structure at one end of the external thread structure. The first end of first vertical connecting rod 3 and 2 threaded connection of solid fixed ring anchor clamps, through-hole sleeve pipe 4 threaded connection between the second end of first vertical connecting rod 3 and the first end of second vertical connecting rod 16, the second end of second vertical connecting rod 16 is connected with lever 6 is articulated, can shorten or extend telescopic rod structure after through-hole sleeve pipe 4 is rotatory. The two ends of the through hole sleeve 4 are provided with internal threads, and the middle part of the through hole sleeve is provided with a hexagonal bulge for screwing rotation. And a load sensor 5 for detecting tensile force is arranged on the second vertical connecting rod 16, the load sensor 5 can adopt an SBT 641, and the tensile force of the telescopic rod structures on two sides is ensured to be consistent through the load sensor 5.
Referring to fig. 3, the four-jaw chuck 9 of the present embodiment includes a latch 10, an inner hexagonal jackscrew modified bolt 11, and two fixing points 12 symmetrically distributed, the four-jaw chuck 9 and the branch pipe 2 are in transition fit through the four latches 10, a tooth structure is arranged at the bottom of the latch 10, and is engaged and fixed with the inner hexagonal jackscrew modified bolt 11, the inner hexagonal jackscrew modified bolt 11 is in threaded connection with the four-jaw chuck 9, and a clamping groove engaged with the tooth structure at the bottom of the latch 10 is arranged at the middle of the inner hexagonal jackscrew modified bolt 11, as shown in fig. 6; the fastening point 12 is connected to the lever 6 by a hinge. And both ends of the lever member 6 are hinge structures.
Referring to fig. 4, the fixing ring clamp 2 of the present embodiment includes two half ring clamps, two ends of the two half ring clamps are connected by a hexagon bolt 15, and a threaded hole for connecting with the first vertical connecting rod 3 or the vertical supporting rod 7 is formed in the middle of one of the half ring clamps. Two ends of the two semi-ring clamps are provided with two symmetrically distributed fixing threaded holes, and the fixing threaded holes can be matched with the hexagon bolts 15 with the same specification for use. The tightness of the fixing ring clamp 2 can be adjusted by means of a hexagon bolt 15.
This embodiment the first end of vertical support bar 7 and fixed ring anchor clamps 2 threaded connection, its second end is equipped with hinge seat 8, pass through bolt connection between hinge seat 8 and the lever 6. The hinge seat 8 is used as a connecting device, dead points can appear during working, and the phenomenon of instability of a rod piece in the force transmission process is avoided. The hinge base 8 comprises an upper hinge and a lower hinge base, and the upper hinge and the lower hinge base are in medium clearance fit, as shown in fig. 5.
In the embodiment, the main pipe 1, the fixing ring clamp 2, the branch pipe 14 and the four-jaw chuck 9 are connected in a transition fit manner. The outer surface of the hexagonal protrusion of the through-hole sleeve 4 should be subjected to wear-resistant treatment. Lubrication treatment is required to be carried out between the outer thread ends of the fixing ring clamp 2 and the first vertical connecting rod, between two threaded holes and the hexagon bolts 15 which are symmetrically distributed on the fixing ring clamp 2, and between the first vertical connecting rod 3 and the through hole sleeve 4 as well as between the second vertical connecting rod 16 and the through hole sleeve 4.
The working process of the invention is as follows: the method comprises the following steps that firstly, a fixing ring clamp 2 and a four-grab chuck 9 are used for fixing the positions of a main pipe 1 and a branch pipe 14 respectively, then a hexagonal bulge on a through hole sleeve 4 with a hexagonal bulge in the middle is screwed through a wrench during welding, so that a telescopic rod structure generates a vertical downward tensile force, the tensile force generated by the telescopic rod structures on two sides is equal under the action of a load sensor 5, the force generated by the telescopic rod structure can provide the branch pipe 14 with a vertical upward tensile force through a lever structure, when the lever structure works, a vertical support rod 7, the fixing ring clamp 2 and a lower hinge seat of a hinge seat 8 are used as supports, and an upper hinge of the hinge seat 8 and a lever piece 6 are used as force transmission parts for flexible movement; at this time, the branch pipe 14 and the main pipe 1 are welded to form a weld joint 13, and the unloading welding is finished until the welding process is finished
The applied pulling force can generate a vertical downward residual compressive stress on the welding joint, so that the welding joint with the residual compressive stress on the surface can well improve the fatigue strength, reduce the welding deformation and effectively reduce the generation of welding cold cracks, thereby improving the welding quality and improving the corrosion resistance of the joint.
Claims (10)
1. A device for generating residual compressive stress of a welded joint of intersecting pipes is characterized in that: the four-jaw telescopic pipe comprises a main pipe and a branch pipe which are welded into a whole and are vertically arranged, wherein four fixing ring clamps are sleeved on the main pipe and symmetrically arranged at two sides of the branch pipe, telescopic rod structures are vertically connected to the fixing ring clamps at two sides, a vertical supporting rod is vertically connected to the two fixing ring clamps in the middle, a four-jaw chuck is mounted on the branch pipe, lever members are connected between the four-jaw chuck and the upper ends of the telescopic rod structures at two sides, and the upper ends of the vertical supporting rods are connected with the corresponding lever members to form a lever structure; when the main pipe and the branch pipe are welded, the telescopic rod structure is contracted, and the lever piece is lifted upwards to pull the four-jaw chuck to generate welding tension, so that residual compressive stress after welding is formed.
2. The device for generating residual compressive stress of a welded joint of intersecting pipes according to claim 1, wherein: the telescopic rod structure comprises a first vertical connecting rod, a through hole sleeve and a second vertical connecting rod, wherein the first end of the first vertical connecting rod is in threaded connection with the fixing ring clamp, the second end of the first vertical connecting rod is in threaded connection with the first end of the second vertical connecting rod, the second end of the second vertical connecting rod is hinged to the lever piece, and the telescopic rod structure can be shortened or extended after the through hole sleeve rotates.
3. The apparatus for generating residual compressive stress in a welded joint of intersecting pipes according to claim 2, wherein: the both ends of through-hole sleeve pipe are equipped with the internal thread, and its middle part is equipped with and is used for twisting the rotatory hexagonal arch of moving.
4. The apparatus for generating residual compressive stress in a welded joint of intersecting pipes according to claim 2, wherein: and a load sensor for detecting tensile force is arranged on the second vertical connecting rod, and the tensile force of the telescopic rod structures at two sides is ensured to be consistent through the load sensor.
5. The device for generating residual compressive stress of a welded joint of intersecting pipes according to claim 1, wherein: the first end of the vertical supporting rod is in threaded connection with the fixing ring clamp, the second end of the vertical supporting rod is provided with a hinge seat, and the hinge seat is connected with the lever piece through a bolt.
6. The device for generating residual compressive stress of the welded joint of the intersecting pipes according to claim 5, wherein: the hinge seat comprises an upper hinge and a lower hinge seat, and the upper hinge and the lower hinge seat are in medium clearance fit.
7. The device for generating residual compressive stress of a welded joint of intersecting pipes according to claim 1, wherein: the fixing ring clamp comprises two semi-ring clamps, the two ends of each of the two semi-ring clamps are connected through a hexagon bolt, and a threaded hole used for being connected with the first vertical connecting rod or the vertical supporting rod is formed in the middle of one of the semi-ring clamps.
8. The apparatus for generating residual compressive stress in a welded joint of intersecting pipes according to claim 7, wherein: two symmetrically distributed fixing threaded holes are formed in the two ends of each semi-ring clamp and are connected with the hexagon bolts.
9. The device for generating residual compressive stress of a welded joint of intersecting pipes according to claim 1, wherein: four-jaw chuck includes latch, hexagon socket head cap screw reforms transform bolt and two fixed points of symmetric distribution, four-jaw chuck and branch pipe are through four latch transition fit, there is tooth structure latch bottom, and it is fixed with hexagon socket head cap screw reforms transform bolt meshing, fixed point and lever spare hinged joint.
10. The device for generating residual compressive stress of a welded joint of intersecting pipes according to claim 1, wherein: the main pipe is connected with the fixed ring clamp, the branch pipe is connected with the four-jaw chuck in a transition fit mode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911204889.4A CN110802364A (en) | 2019-11-29 | 2019-11-29 | Device for generating residual compressive stress of tubular welded joint |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911204889.4A CN110802364A (en) | 2019-11-29 | 2019-11-29 | Device for generating residual compressive stress of tubular welded joint |
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| Publication Number | Publication Date |
|---|---|
| CN110802364A true CN110802364A (en) | 2020-02-18 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911204889.4A Pending CN110802364A (en) | 2019-11-29 | 2019-11-29 | Device for generating residual compressive stress of tubular welded joint |
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| CN (1) | CN110802364A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113182762A (en) * | 2021-03-24 | 2021-07-30 | 内蒙古工业大学 | Auxiliary welding device for vertical connecting pipe |
| CN114000849A (en) * | 2021-11-26 | 2022-02-01 | 京鸿石油钻采工程技术有限公司 | Casing head, casing head combination and wellhead assembly |
| CN115026493A (en) * | 2022-05-26 | 2022-09-09 | 华能伊敏煤电有限责任公司 | Auxiliary tool for repairing cracks of high-temperature and high-pressure pipe valve for boiler |
| CN115091118A (en) * | 2022-05-30 | 2022-09-23 | 华能伊敏煤电有限责任公司 | Crack repairing and fixing device for multi-connected pipes of boiler reheater header |
-
2019
- 2019-11-29 CN CN201911204889.4A patent/CN110802364A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113182762A (en) * | 2021-03-24 | 2021-07-30 | 内蒙古工业大学 | Auxiliary welding device for vertical connecting pipe |
| CN114000849A (en) * | 2021-11-26 | 2022-02-01 | 京鸿石油钻采工程技术有限公司 | Casing head, casing head combination and wellhead assembly |
| CN115026493A (en) * | 2022-05-26 | 2022-09-09 | 华能伊敏煤电有限责任公司 | Auxiliary tool for repairing cracks of high-temperature and high-pressure pipe valve for boiler |
| CN115091118A (en) * | 2022-05-30 | 2022-09-23 | 华能伊敏煤电有限责任公司 | Crack repairing and fixing device for multi-connected pipes of boiler reheater header |
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