Welding tool and method for lubricating oil pipe of torsional vibration damper of low-speed diesel engine

Abstract

The invention discloses a welding tool and method for a lubricating oil pipe of a torsional vibration damper of a low-speed diesel engine, the tool comprises bottom base I-shaped steel, side base I-shaped steel, a side base transverse plate and a bottom base transverse plate, the bottom base I-shaped steel is placed on the ground, the side base I-shaped steel and the bottom base transverse plate are welded on the bottom base I-shaped steel, and the included angle between the side base I-shaped steel and the bottom base transverse plate is 90 degrees; a positioning hole is formed in the upper surface and is used for positioning a lubricating oil pipe flange; the welding method comprises the steps that a flange is pre-connected, a lubricating oil pipe is hoisted to a tool transverse plate datum plane, and a positioning pin locking hole position is inserted; and the included angle between the axes of the left flange and the right flange of the lubricating oil pipe is calibrated to be 90 + / -0.5 degrees, full welding is completed through the TIG segmented welding technology, the deformation is controlled to be smaller than or equal to 0.15 mm, and finally assembly welding of the torsional vibration damper lubricating oil pipe is completed. The positioning device solves the positioning problem of the lubricating oil pipe before welding, error accumulation is avoided, the working efficiency and precision are improved, the sealing performance of lubricating oil pipe parts is guaranteed, and the positioning device has the advantages of being simple in structure, convenient to install, reliable in positioning, high in precision and high in efficiency.

Description

Technical Field

[0001] The present invention relates to the manufacturing process of marine low-speed diesel engines, and particularly to a welding tooling and method for the lubricating oil pipe of the torsional vibration damper of a low-speed diesel engine, belonging to the technical field of marine diesel engine manufacturing. Background Technique

[0002] In marine low-speed diesel engines, the welding of the lubricating oil pipe of the torsional vibration damper needs to ensure the accuracy of the angle with the flange surface to guarantee the sealing performance. Since the welding and assembly operations of the lubricating oil pipe of the torsional vibration damper of a low-speed diesel engine involve the welding of multiple components, cumulative errors are likely to occur, thereby affecting the accuracy and sealing performance of the damper lubricating oil pipe components. Such cumulative errors may even affect the reliability and safety of the entire engine.

[0003] The current traditional welding methods have the following problems: ① Low positioning accuracy, relying on manual adjustment of the installation angle of the lubricating oil pipe, which is prone to installation deviation and affects the damper performance; ② Insufficient rigidity of the temporary tooling, prone to deformation; ③ Low efficiency, requiring multiple disassembly and assembly for leak detection, with a high rework rate. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: to overcome the defects of low positioning accuracy, easy deformation of the tooling, and error accumulation in the existing welding and assembly methods for the lubricating oil pipe of the torsional vibration damper, and to provide a welding tooling and method for the lubricating oil pipe of the torsional vibration damper of a low-speed diesel engine, which can quickly and accurately complete the positioning and fastening of each component during welding operations, avoid cumulative errors caused by subsequent welding processing, thereby achieving the purpose of ensuring the processing accuracy and sealing performance of the lubricating oil pipe of the torsional vibration damper, and obtaining the effects of improving work efficiency and welding and assembly accuracy.

[0005] The technical solutions adopted by the present invention to solve its technical problems are as follows:

[0006] A welding tooling for the lubricating oil pipe of the torsional vibration damper of a low-speed diesel engine, wherein the lubricating oil pipe of the torsional vibration damper is formed by connecting a main pipe and two branch pipes, and the end face of the right flange of the branch pipe is perpendicular to the end face of the left flange of the main pipe in space; characterized in that: the welding tooling includes a bottom base I-beam, a side base I-beam, a side base cross plate, and a bottom base cross plate;

[0007] The bottom base I-beam is placed on the ground, the side base I-beam is vertically welded to one end of the bottom base I-beam, the bottom base cross plate is horizontally welded to the upper plane of the other end of the bottom base I-beam, and the side base cross plate is welded to the side of the side base I-beam in the vertical direction and faces the bottom base cross plate, ensuring that the included angle between the side base cross plate and the bottom base cross plate is 90° ± 0.2°;

[0008] Four positioning holes are provided on the lateral base cross plate for positioning the left flange of the main pipe. These four positioning holes are evenly distributed on the same positioning circle. Two groups of positioning holes are provided on the bottom base cross plate. Each group of two positioning holes is distributed on a positioning circle and symmetrically distributed along the diameter for positioning the two right flanges of the branch pipe. The positions of the positioning circles and positioning holes on the lateral base cross plate, and the positions of the positioning circles and positioning holes on the bottom base cross plate are determined by the technical requirements of the torsional vibration damper oil pipe.

[0009] Furthermore, the flatness error of the lateral base cross plate and the bottom base cross plate is ≤ 0.1 mm / m.

[0010] Furthermore, the levelness error of the bottom base I-beam is ≤ 0.1 mm / m, and the length is determined according to the length of the torsional vibration damper oil pipe.

[0011] Furthermore, the hole pitch tolerance between the positioning holes on the lateral base cross plate and between the positioning holes on the bottom base cross plate is ±0.05 mm.

[0012] Another technical solution of the present invention is as follows:

[0013] A welding method for the torsional vibration damper oil pipe of a low-speed diesel engine implemented by using the above welding fixture includes the following steps:

[0014] 1) Initially connect the left flange of the main pipe to the lateral base cross plate through bolts, make the end face of the left flange fit the plane of the lateral base cross plate, ensure that the fitting gap is ≤ 0.1 mm, check and ensure that the coaxiality error between the through-hole axis of the left flange and the positioning circle is ≤ 0.2 mm;

[0015] 2) Pre-connect the two right flanges of the branch pipe to the bottom base cross plate through bolts, make the end face of the right flange fit the plane of the bottom base cross plate, lock the flange hole positions through positioning pins, measure and adjust the deviation between the through-hole axis of the right flange and the positioning circle axis by using a micrometer to be ≤ 0.15 mm, and temporarily fix the right flange and the bottom base cross plate by spot welding;

[0016] 3) Hoist the torsional vibration damper oil pipe to the installation height. After completing the positioning at both ends, measure the included angle between the axis of the left flange and the axis of the right flange. By adjusting the angle of the lateral base I-beam, achieve the precise alignment of this included angle. Then, perform spot welding positioning at the connection between the main pipe and the left flange and at the connections between the two branch pipes and the right flanges. Then, complete the full welding operation by using the TIG welding process;

[0017] 4) Remove the welding fixture, remove the welding slag from the inner wall of the oil pipe, spray an anti-rust coating, polish the weld seam with a grinding wheel, and finally complete the assembly welding of the torsional vibration damper oil pipe.

[0018] Further, in the step 2), the spacing between the spot welds for temporary fixing is 100 mm, and the length of each spot weld is 5 mm.

[0019] Further, in the step 3), for the spot welding positioning at the connection between the main pipe and the left flange and at the connections between the two branch pipes and the right flange, the length of each spot weld is 10 mm, and the spacing is 150 mm;

[0020] The TIG welding process includes: a current of 130 - 150 A, controlling the interlayer temperature ≤ 100°C, monitoring and controlling the welding deformation in real time to be ≤ 0.15 mm, and completing the full welding in three segments.

[0021] Further, in the step 3), the precise alignment of the included angle between the axis of the left flange and the axis of the right flange is α = 90° ± 0.5°.

[0022] Further, in the step 4), removing the welding fixture includes: removing the positioning pins and removing the temporary spot welding fixing points between the right flange and the bottom base cross plate.

[0023] Further, in the step 4), the weld seam is polished to a surface roughness Ra ≤ 3.2 μm. The beneficial technical effects of the present invention are as follows:

[0024] The present invention overcomes the deficiency of the low efficiency of the welding and assembly operation of the slip oil pipe of the existing low-speed diesel engine torsional vibration damper, solves the positioning problem before the welding of the slip oil pipe components, effectively avoids the problem of error accumulation caused by the welding of multiple components in the traditional manufacturing method, improves the efficiency and precision of the welding and assembly operation, ensures the sealing performance of the slip oil pipe components, and has the advantages of simple structure, convenient installation, reliable positioning, high precision, and fast efficiency. Description of the Drawings

[0025] Figure 1 is the front view of the welding fixture of the present invention.

[0026] Figure 2 is Figure 1 the top view of

[0027] Figure 3 is Figure 1 the A - A view of

[0028] Figure 4 is the usage state diagram of the present invention.

[0029] In the figure,

[0030] 1 - bottom base I-beam, 2 - side base I-beam, 3 - side base cross plate, 4 - bottom base cross plate. Detailed Embodiments

[0031] The present invention will be further specifically described in detail below in conjunction with the accompanying drawings and embodiments, but the scope of protection required by the present invention cannot be limited thereby.

[0032] The present invention is used for the welding and assembly operation of the oil slide pipe of the torsional vibration damper of a low-speed diesel engine. Please refer to Figure 4 , the oil slide pipe of the torsional vibration damper is formed by connecting a main pipe A1 and two branch pipes A2, and the end faces of the right flanges C of the two branch pipes A2 are vertically spaced from the end face of the left flange B of the main pipe A1.

[0033] Embodiment

[0034] Please refer to Figure 4 , the welding tooling includes a bottom base I-beam 1, a side base I-beam 2, a side base cross plate 3 and a bottom base cross plate 4, and all components are made of steel.

[0035] Please refer to in conjunction with Figure 1 , Figure 2 and Figure 3 , the bottom base I-beam 1 is placed on the ground as a basic structure, and its length is customized according to the length of the oil slide pipe to meet the requirements of sufficient bearing capacity and good stability of the welding tooling. Place the bottom base I-beam 1 with specifications of 1650 mm × 100 mm × 6 mm horizontally on the assembly platform, and use a level to adjust its levelness to an error ≤ 0.1 mm / m. Vertically weld a side base I-beam 2 with specifications of 100 mm × 100 mm × 6 mm upward at one end of the bottom base I-beam 1 to ensure that the included angle between the two is 90° ± 0.2°. The bottom base cross plate 4 is horizontally welded to the upper plane at the other end of the bottom base I-beam 1, and the side base cross plate 3 is welded vertically to the side of the side base I-beam 2 and faces the bottom base cross plate 4 to ensure that the included angle between the side base cross plate 3 and the bottom base cross plate 4 is 90° ± 0.2°.

[0036] Four Φ16 positioning holes 31 are machined on the side base cross plate 3 for subsequent positioning of the left flange B of the main pipe A1, as shown in Figure 3 , the four Φ16 positioning holes 31 are evenly distributed on the same positioning circle B3, and the hole position tolerance is ±0.05 mm. Four Φ16 positioning holes 41 are machined on the bottom base cross plate 4, as shown in Figure 2, every two of the four positioning holes 41 are distributed in a positioning circle C4. The two positioning circles C4 have the same diameter, and the positions of the two positioning holes 41 on the same positioning circle C4 are symmetrically distributed along the diameter. The hole position tolerance is ±0.05 mm. The four positioning circles C4 are used to position the two right flanges C of the branch pipe A2 subsequently. The positions of the positioning circle B3 and the positioning holes 31 on the side base cross plate 3, and the positions of the positioning circle C4 and the positioning holes 41 on the bottom base cross plate 4 are determined by the technical requirements of the drawing of the lubricating oil pipe.

[0037] Please refer to Figure 4 , the welding method of the lubricating oil pipe for the torsional vibration damper of a low-speed diesel engine according to the present invention is as follows:

[0038] 1) Initially connect the left flange B of the main pipe A1 to the side base cross plate 3 through temporary fixing bolts, so that the end face of the left flange B fits the positioning reference surface of the side base cross plate 3, ensuring that the fitting gap ≤ 0.1 mm. Check the coaxiality error between the through hole axis of the left flange B and the positioning circle B3, ensuring that it ≤ 0.2 mm.

[0039] 2) Pre-connect the two right flanges C of the branch pipe A2 to the bottom base cross plate 4 through M16 bolts, so that the end face of the right flange C fits the positioning reference surface of the bottom base cross plate 4. Insert Φ16 positioning pins into the positioning holes 41 to lock the flange hole positions; measure the deviation between the through hole axis of the right flange C and the axis of the positioning circle C4 through a dial indicator, and adjust it to ≤ 0.15 mm; temporarily fix the right flange C and the bottom base cross plate 4 by spot welding, with a spot welding length of 5 mm at each place and an interval of 100 mm.

[0040] 3) Lift the lubricating oil pipe to the installation height. After positioning both ends of the lubricating oil pipe, measure the included angle α between the axis of the left flange B of the main pipe A1 and the axes of the two right flanges C of the branch pipes A2. By adjusting the support angle of the side base I-beam 2, achieve the precise alignment of this included angle α (α = 90° ± 0.5°); then carry out spot welding positioning at the connection between the main pipe A1 and the left flange B and at the connections between the two branch pipes A2 and the right flanges C, with a spot welding length of 10 mm at each place and an interval of 150 mm; then adopt the TIG welding process, with a current of 130 - 150 A, and complete the full welding operation in three sections. Control the interlayer temperature ≤ 100 °C, and monitor and control the welding deformation amount in real time to ≤ 0.15 mm.

[0041] 4) Remove the Φ16 positioning pins, remove the temporary spot welding fixing points between the right flange C and the bottom base cross plate 4, remove the welding tooling, remove the welding slag from the inner wall of the lubricating oil pipe, spray an anti-rust coating, and use a grinding wheel to polish the weld seam to a surface roughness Ra ≤ 3.2 μm; clean and maintain the bottom base cross plate 4 and the side base cross plate 3 of the welding tooling for repeated use.

[0042] In summary, the present invention solves the problem of low welding and assembly efficiency of the slip oil pipe of the torsional vibration damper for low-speed diesel engines, effectively avoiding the cumulative error problem caused by multi-component welding in the traditional manufacturing method, making the assembly process more efficient, ensuring the manufacturing precision and sealing performance of the slip oil pipe components, and thus improving the operation efficiency and precision of the welding and assembly of the slip oil pipe.

[0043] The above are only the preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any equivalent changes and modifications made according to the content of the present invention application shall fall within the technical scope of the present invention.

Claims

1. A welding tooling for the lubricating oil pipe of a torsional vibration damper of a low-speed diesel engine. The lubricating oil pipe of the torsional vibration damper is formed by connecting a main pipe and two branch pipes. The end face of the right flange of the branch pipe is vertically spaced from the end face of the left flange of the main pipe. It is characterized in that: The welding fixture includes a bottom base I-beam, a side base I-beam, a side base cross plate and a bottom base cross plate; The bottom base I-beam is placed on the ground. The side base I-beam is vertically welded to one end of the bottom base I-beam. The bottom base cross plate is horizontally welded to the upper plane of the other end of the bottom base I-beam. The side base cross plate is vertically welded to the side of the side base I-beam and faces the bottom base cross plate, ensuring that the included angle between the side base cross plate and the bottom base cross plate is 90°±0.2°; Four positioning holes are provided on the side base cross plate for positioning the left flange of the main pipe. The four positioning holes are evenly distributed on the same positioning circle. Two groups of positioning holes are provided on the bottom base cross plate. Each group of two positioning holes is distributed on a positioning circle and is symmetrically distributed along the diameter for positioning the two right flanges of the branch pipe. The positions of the positioning circle and the positioning holes on the side base cross plate, and the positions of the positioning circle and the positioning holes on the bottom base cross plate are determined by the technical requirements of the torsional vibration damper oil pipe; 2. The welding tooling for the lubricating oil pipe of the torsional vibration damper of a low-speed diesel engine according to claim 1, wherein: The flatness error of the side base cross plate and the bottom base cross plate is ≤0.1mm / m.

3. The welding tooling for the lubricating oil pipe of the torsional vibration damper of a low-speed diesel engine according to claim 1, characterized in that: The levelness error of the bottom base I-beam is ≤0.1mm / m, and the length is determined according to the length of the torsional vibration damper oil pipe; 4. The welding tooling for the lubricating oil pipe of the torsional vibration damper of a low-speed diesel engine according to claim 1, characterized in that: The hole pitch tolerance between the positioning holes on the side base cross plate and between the positioning holes on the bottom base cross plate is ±0.05mm.

5. A welding method for the slip oil pipe of the torsional vibration damper of a low-speed diesel engine implemented by using the welding tooling described in claim 1, characterized in that: The welding method includes the following steps: 1) Initially connect the left flange of the main pipe to the side base cross plate through bolts, so that the end face of the left flange fits the plane of the side base cross plate, ensuring that the fitting gap is ≤0.1mm, and checking and ensuring that the coaxiality error between the through hole axis of the left flange and the positioning circle is ≤0.2mm; 2) Pre-connect the two right flanges of the branch pipe to the bottom base cross plate through bolts, so that the end face of the right flange fits the plane of the bottom base cross plate. Lock the flange hole positions through positioning pins. Measure and adjust the deviation between the through hole axis of the right flange and the axis of the positioning circle by a micrometer to be ≤0.15mm, and temporarily fix the right flange and the bottom base cross plate by spot welding; 3) Lift the torsional vibration damper oil pipe to the installation height. After completing the positioning at both ends, measure the included angle between the axis of the left flange and the axis of the right flange. By adjusting the angle of the side base I-beam, achieve precise alignment of this included angle. Then perform spot welding positioning at the connection between the main pipe and the left flange and at the connections between the two branch pipes and the right flanges. Then complete the full welding operation using the TIG welding process; 4) Remove the welding fixture, remove the welding slag from the inner wall of the oil pipe, spray an anti-rust coating, use a grinding wheel to polish the weld seam, and finally complete the assembly welding of the torsional vibration damper oil pipe; 6. The welding method for the lubricating oil pipe of the torsional vibration damper of a low-speed diesel engine according to claim 5, characterized in that: In the step 2), the spacing between the spot welds for temporary fixing by spot welding is 100mm, and the length of each weld is 5mm; 7. The welding method for the lubricating oil pipe of the torsional vibration damper for low-speed diesel engines according to claim 5, characterized in that: In the step 3), the length of each spot weld for positioning at the connection between the main pipe and the left flange and at the connections between the two branch pipes and the right flanges is 10mm, and the spacing is 150mm; The TIG welding process includes: a current of 130 - 150 A, interlayer temperature control ≤ 100 °C, real-time monitoring and control of welding deformation within ≤ 0.15 mm, and full welding is completed in three segments.

8. The welding method for the lubricating oil pipe of the torsional vibration damper for a low-speed diesel engine according to claim 5, characterized in that: In the said step 3), the precise alignment of the angle between the axis of the left flange and the axis of the right flange is α = 90° ± 0.5°.

9. The welding method for the lubricating oil pipe of the torsional vibration damper for low-speed diesel engines according to claim 5, characterized in that: In the said step 4), removing the welding fixture includes: removing the positioning pins and removing the temporary spot welding fixed points between the right flange and the bottom base plate.

10. The welding method for the lubricating oil pipe of the torsional vibration damper of a low-speed diesel engine according to claim 5, characterized in that: In the said step 4), the weld seam is polished to a surface roughness Ra ≤ 3.2 μm.

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