Welding fixture for thin-wall cylindrical part

Abstract

The utility model provides a welding fixture for a thin-wall cylindrical part, which belongs to the technical field of welding, namely a welding fixture capable of being simply disassembled and assembled, and comprises an inner support part and an outer hoop part, the inner supporting ring is provided with two sections, and the two sections of the inner supporting ring are assembled into an annular structure. Supporting screws and cushion caps are arranged; the supporting height can be adjusted by screwing the supporting screws, and the alignment tolerance of the two sides of the connector is adjusted. The supporting height of the welding seam inner supporting clamp can be adjusted, and the outer hoop clamps are additionally arranged on the outer walls of the two sides of a welding seam, so that the welding joint gap and the unfitness of butt joint are adjusted, the cylinder roundness is corrected, and the purposes of controlling welding deformation and optimizing the welding quality are achieved.

Description

Technical Field

[0001] This utility model belongs to the field of welding technology, specifically relating to a welding fixture, and more particularly to a set of special fixtures and its unique connection and positioning method used in the welding process, which can be used for circumferential welding of thin-walled cylindrical parts. Background Technology

[0002] Thin-walled cylindrical parts are widely used in both military and civilian fields. These parts are generally formed using spinning, stamping, and welding processes, with circumferential welds being the most common type of weld. These parts are mostly used as pressure-bearing components in products, such as boiler cylinders. Therefore, they have high requirements for part dimensions and weld quality, such as roundness, misalignment, and welding deformation. Circumferential welds typically use internal supports and external clamps to control misalignment and deformation, as well as roundness correction, during assembly. Taking a thin-walled cylindrical part as an example, this part is 1370mm long, 601mm in diameter, with a wall thickness of only 2.8mm and a material strength of 1600MPa~1750MPa. The coaxiality requirement for the front and rear ends during machining is 0.12. The inner diameter of the front end is only Φ132mm, and the inner diameter of the rear end is Φ326mm, representing a typical "small opening, large body" shape with convergent front and rear ends. Therefore, welding presents the following challenges:

[0003] (1) The cylinder wall is thin, the diameter is large and the length-to-diameter ratio is small. When the welded joint is assembled, the cylinder roundness is poor and the misalignment is large. The radial deformation is large when the circumferential weld is welded.

[0004] (2) The cylinder has a large diameter and a long weld, making it difficult to control the misalignment and welding deformation along the entire length of the weld.

[0005] (3) The inner hole size at the front and rear ends of the part is smaller than that of the straight cylinder section, and the weld seam support fixture is difficult to remove from the two ends after welding. Utility Model Content

[0006] I. Technical problems to be solved

[0007] The technical problem and objective of this utility model is to provide a welding fixture for thin-walled cylindrical parts, which is an easily detachable welding fixture. By adjusting the support height of the inner support fixture of the weld and adding outer hoop fixtures on both sides of the outer wall of the weld, the gap and misalignment of the weld joint can be adjusted and the roundness of the cylinder can be corrected, thereby achieving the purpose of controlling welding deformation and optimizing welding quality.

[0008] II. The technical solution of this utility model is:

[0009] The key feature of this invention is that the support height of the clamp can be adjusted by means of a threaded connection, and it can be disassembled and assembled separately.

[0010] A welding fixture for thin-walled cylindrical parts includes an inner support portion and an outer hoop portion; characterized in that the inner support portion includes: an inner support ring, a support screw, a washer, a connecting screw, and a hook; the inner support ring has two sections, which are positioned and aligned by a positioning pin and a positioning hole, and the two sections of the inner support ring are assembled into a ring structure; the inner support ring is provided with a threaded hole covering the entire circumference of the ring; the support screw passes through the threaded hole of the inner support ring from the inside of the inner support ring, and the support screw engages with the threaded hole of the inner support ring through its threads; the support screw extends out of the inner support ring. The outer diameter top of the ring threaded hole and the outer end of the support screw are threaded with the washer cap. The number of turns of the support screw, inner support ring and washer cap can be adjusted. Each inner support ring has a connecting screw at both ends. One end of the hook is connected to the connecting screw of one inner support ring and can rotate. The other end of the hook can be hooked onto the connecting screw of another inner support ring. The outer hoop part includes a ring hoop, an outer hoop bolt and an outer hoop nut. The outer hoop bolt and outer hoop nut connect the two ring hoops and the two ring hoops form a ring.

[0011] Furthermore, the hook adopts a through-hole structure.

[0012] Furthermore, the ring hoop has an opening groove in its circumference, and the weld is located at the opening groove.

[0013] Furthermore, the inner diameter of the ring formed by the two ring segments is the outer diameter of the thin-walled cylindrical part.

[0014] Furthermore, the ring is fitted onto the weld of the thin-walled cylindrical part, and the circumferentially open groove of the ring is used for the positioning welding of the weld.

[0015] Furthermore, the inner support ring has two rows of threaded holes, which are located on two axially distributed circumferences on the inner support ring.

[0016] Furthermore, the top of the gasket tightly presses against the inside of both sides of the weld seam of the thin-walled cylindrical part.

[0017] Furthermore, both the support screws and connecting screws are standard parts.

[0018] Furthermore, there are support screws of different lengths.

[0019] Furthermore, the pad cap is supported on the inner wall of the cylindrical part of the thin-walled cylindrical part.

[0020] III. The technical effects of this utility model are:

[0021] 1. Excellent dynamic adjustability of support height, adjustable 360° on both sides of the welded joint: When there are slight changes in the size and structure of the welded parts, the support height can be adjusted by turning the support screws to adjust the misalignment on both sides of the joint. In addition, the roundness of the cylinder can be corrected by applying external force through the external hoop device.

[0022] 2. Good structural interchangeability: This utility model adopts a modular and standardized design, and both the support screw 2 and the connecting screw 4 are standard parts. When the size of the weldment is adjusted, the diameter of the inner support part can be adjusted by changing the screws of different lengths and adjusting the height of the washer 3. The top diameter of the washer 3 is consistent with the inner diameter of the thin-walled cylindrical part, and the inner diameter of the weldment that can be supported can be adjusted by modifying the size of the washer 3.

[0023] 3. Simple assembly method and high reliability: This utility model is mainly assembled by thread fastening, and can be assembled and disassembled using ordinary wrenches and Allen wrenches, with high replacement efficiency.

[0024] 4. Consistent and controllable assembly effect: Support screw 2 is a key component that plays a supporting and adjusting role in the inner support part. It is tightened by using a torque wrench to fix the torque, so as to ensure that the supporting force on both sides and the entire length of the weld is the same, to prevent deformation during the assembly of the welding fixture, and to achieve uniform and controllable deformation during the welding process. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the inner support portion of the welding fixture of this utility model.

[0026] Figure 2 This is a schematic diagram showing the assembly effect of the inner support portion of the welding fixture of this utility model.

[0027] Figure 3 This is a schematic diagram of the outer hoop portion of the welding fixture of this utility model.

[0028] Figure 4 This is a schematic diagram showing the assembly effect of the outer hoop portion of the welding fixture of this utility model.

[0029] Among them, 1: inner support ring; 2: support screw; 3: washer; 4: connecting screw; 5: hook; 6: ring clamp; 7: outer clamp bolt; 8: outer clamp nut. Detailed Implementation

[0030] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings:

[0031] like Figure 1 , Figure 2 As shown, the inner support part of this utility model includes: an inner support ring 1, a support screw 2, a washer 3, a connecting screw 4, and a hook 5.

[0032] The inner support ring 1 has a full-length threaded hole in its diameter direction that covers the entire circumference, serving as the basis for the radial support function of the inner support portion. The support screw 2 is connected and fixed to the inner support ring 1 by threads; after the support screw 2 passes through the inner support ring 1, at the top of the threaded portion of the support screw 2 extending out of the outer diameter of the inner support ring 1, the support screw 2 is also connected to the washer 3 by threads. By adjusting the number of turns of the threads of the support screw 2, the inner support ring 1, and the washer 3, the support height of the support portion of this utility model for the inside of the weldment is adjusted.

[0033] The inner support ring 1 has a pointed locating pin and a locating hole at its top. The two inner support rings 1 are aligned and positioned through the pin hole. The inner support ring 1 is connected to the hook 5 at the mating part by the connecting screw 4. The hook 5 adopts a through-hole design, so that the hook 5 can rotate freely on the connecting screw 4. Rotate the hook 5 clockwise so that it latches onto the connecting screw 4 on the other inner support ring 1, assembling the entire inner support fixture into a ring structure.

[0034] By adjusting the number of turns of the threads on the support screw 2 and the washer 3, the support height on both sides of the weld inside the thin-walled cylinder can be adjusted 360°. During fixture assembly, the threaded support part on one side of the inner support section can be tightened to the weld side to obtain support, and then the weldment at the other end can be installed on the other side of the fixture and the threads on the corresponding side can be tightened, thereby achieving the effect of separate clamping. After welding is completed, rotating the hook 5 counterclockwise disengages it from the connecting screw 4 on the opposite inner support ring 1. Rotating the support screws 2 in each direction reduces the diameter of the entire inner support section, allowing the two inner support rings 1 to be separated and easily removed from the small end of the weldment.

[0035] like Figure 3 , Figure 4 As shown, the outer hoop part of this utility model includes a ring hoop 6, an outer hoop bolt 7, and an outer hoop nut 8.

[0036] After the inner support part of this utility model is clamped, the two ring hoops 6 of the outer hoop part are fitted on both sides of the weld of the thin-walled cylindrical part, and the two ring hoops 6 are connected and tightened with two sets of outer hoop bolts 7 and outer hoop nuts 8 to form a ring.

[0037] By setting the inner diameter of the ring 6 to the outer diameter of the thin-walled cylindrical part, the two sides of the weld face of the thin-walled cylindrical part can be locked. The roundness of the cylinder and the amount of weld misalignment can be corrected by rigidly connecting the entire outer ring. In addition, the two sections of the ring 6 are designed with circumferential openings, which can be used for tack welding operations on the front side of the weld after clamping.

[0038] The working process and principle of this utility model

[0039] In this invention, the inner support ring 1, support screw 2, and washer 3 are connected by threads in the inner support part. By adjusting the number of turns of the threaded connection between the support screw 2 and the inner support ring 1, the top of the washer 3 tightens the inner sides of the weld seam of the thin-walled cylindrical part. The hook 5, by rotating on the connecting screw 4 installed on the inner support ring 1, serves to connect the two sections of the inner support ring 1 radially. The two sections of the outer hoop 6 are connected into a ring by the outer hoop bolt 7 and the outer hoop nut 8. The inner diameter of the hoop 6 further limits the amount of weld misalignment.

[0040] The specific working state of the welding fixture described in this utility model is as follows:

[0041] 1. Assembly of the internal support section

[0042] Screw the support screw 2 into the inner support ring 1 from the inside. Then screw the washer 3 onto the top part of the support screw 2 that extends out of the outer diameter of the inner support ring 1. Connect the hook 5 to one end of the inner support ring 1 with the connecting screw 4. Perform the same operation on both inner support rings. Align the two inner support rings 1 and connect them into a ring through the positioning holes and positioning pins on the end faces. Rotate the hook 5 on the connecting screw 4 clockwise so that the hook 5 hooks onto the connecting screw 4 on the other inner support ring 1. In this way, the inner support part can form a complete ring.

[0043] Lay the thin-walled cylindrical part to be welded flat. Insert one side of the integrated inner support portion into one end of the cylindrical part. Use a fixed torque wrench to adjust the thread height of the support screw 2 so that the washer 3 can be firmly supported on the inner wall of the cylindrical part. Place the other end of the weldment onto the other side of the inner support portion. Repeat the above steps to connect the two weldment sections. By adjusting the thread height of the support screw 2, the misalignment on both sides of the weldment can be adjusted.

[0044] 2. Assembly of the outer hoop section

[0045] Two ring hoops 6 are fitted onto both sides of the weld seam of the thin-walled cylindrical part. The two ring hoops 6 are connected and tightened with two sets of outer hoop bolts 7 and outer hoop nuts 8 to form a rigid ring. The tack welding operation of the thin-walled cylindrical part is performed at the opening groove set around the ring hoops 6.

[0046] 3. Disassembly of the outer hoop section

[0047] After the tack welding is completed and the welded parts have cooled down, use a wrench to unscrew the outer hoop bolt 7 and the outer hoop nut 8, then remove the two sections of the ring hoop 6, and then perform the circumferential weld.

[0048] 4. Disassembly of the inner support section

[0049] After the circumferential weld is completed and the welded part has cooled down, insert a wrench into the open end of the welded part, loosen the support screw 2 inward, rotate the hook 5 counterclockwise, pull out the two inner support rings 1, and take out the two inner support parts from the open end of the thin-walled cylindrical part respectively.

Claims

1. A welding fixture for thin-walled cylindrical parts, comprising an inner support part and an outer hoop part, characterized in that the inner support part comprises an inner support ring (1), support screws (2), a spacer cap (3), connecting screws (4), and hooks (5); the inner support ring (1) has two sections, which are positioned and aligned by positioning pins and positioning holes, and are assembled into a ring structure; the inner support ring (1) is provided with threaded holes covering the entire circumference of the ring; the support screws (2) are inserted into the threaded holes of the inner support ring (1) from the inner side of the inner support ring (1), and are screwed into the threaded holes of the inner support ring (1) by threads; the outer diameter of the top end of the support screws (2) extending out of the threaded holes of the inner support ring (1) is screwed into the spacer cap (3) by threads, and the number of turns of the support screws (2) screwed into the inner support ring (1) and the spacer cap (3) can be adjusted; each section of the inner support ring has connecting screws (4) at both ends, one end of the hooks (5) is connected to the connecting screws (4) of one section of the inner support ring, and can rotate; the other end of the hooks (5) can be buckled to the connecting screws (4) of the other section of the inner support ring; the outer hoop part comprises a hoop (6), outer hoop bolts (7), and outer hoop nuts (8); the outer hoop bolts (7) and the outer hoop nuts (8) connect two sections of the hoop (6), and the two sections of the hoop (6) form a ring. The hooks (5) adopt a through-hole structure. The hoop (6) has an open slot in the circumferential direction, and the weld is located at the open slot. The inner diameter of the ring formed by the two sections of the hoop is the outer diameter of the thin-walled cylindrical part. The hoop is sleeved on the weld of the thin-walled cylindrical part, and the open slot provided on the hoop (6) is used for positioning welding of the weld. The threaded holes of the inner support ring (1) have two rows, and the two rows of threaded holes are respectively located on two circumferences distributed in the axial direction on the inner support ring.

2. A welding fixture for thin-walled cylindrical parts according to claim 1, characterized in that The top end of the spacer cap tightly presses the inside of the weld on both sides of the thin-walled cylindrical part.

3. A welding fixture for thin-walled cylindrical parts as defined in claim 1, characterized in that The support screws have different lengths.

4. A welding fixture for thin-walled cylindrical parts as defined in claim 1, wherein The spacer cap is supported on the inner wall of the cylindrical part of the thin-walled cylindrical part.

5. A welding fixture for thin-walled cylindrical parts as defined in claim 1, wherein ​ 6. A welding fixture for thin-walled cylindrical parts as defined in claim 1, wherein ​ 7. A welding fixture for thin-walled cylindrical parts according to claim 6, characterized in that ​ 8. A welding fixture for thin-walled cylindrical parts as defined in claim 1, wherein ​ 9. A welding fixture for thin-walled cylindrical parts as defined in claim 1, wherein ​

Images