A method for welding the inner hole of a rectangular spline short bushing

Abstract

A method for surfacing the inner hole of a rectangular spline short bushing includes: firstly, surfacing a transition layer on the surface of the spline inner hole; then, machining the transition layer; after passing dye penetrant testing, surfacing a fusion layer on the surface of the transition layer; wherein the welding wires used for the transition layer and the fusion layer are SNi2061 and SNi4060, respectively; and the surfacing process of the transition layer and the fusion layer includes: firstly, placing the rectangular spline short bushing on a roller frame; then, adjusting the position of the rectangular spline using the roller frame so that the root radius (R-angle) of a certain spline tooth is in a boat-shaped welding position; then, surfacing the R-angle; for each plane of the spline tooth, first adjusting the position of the rectangular spline using the roller frame so that a certain plane is in a flat welding position; then, surfacing the plane; and surfacing the remaining spline teeth in the same manner. This invention effectively ensures the performance quality of the surfacing layer.

Description

Technical Field

[0001] This invention belongs to the field of workpiece welding technology, and specifically relates to a method for overlaying welding the inner hole of a rectangular spline short bushing. Background Technology

[0002] A rectangular splined short bushing is typically fitted onto the telescopic bow rudder system of a ship. This splined short bushing is used after being assembled with the splined shaft on the telescopic bow rudder system, and its structure is as follows: Figure 1 As shown.

[0003] The base material for rectangular spline short bushings is mostly 0Cr16Ni5Mo stainless steel. According to design requirements, a layer of Monel alloy material needs to be deposited into the inner hole of the spline, and the specific technical requirements for the deposited layer are as follows: (1) The surface hardness of the weld overlay is less than 185HB.

[0004] (2) The tensile and compressive yield strengths of the fusion line and the weld overlay are both greater than 286 MPa, and the shear strengths are both greater than 159 MPa.

[0005] (3) The surface of the weld overlay is qualified by PT (NB / T47013-2015) Grade I, and the welding deformation during the weld overlay process is controlled to be no more than 1 mm.

[0006] Because the inner diameter of the rectangular spline is only 380mm, the space is small and the welding space is limited. Furthermore, it is difficult to guarantee the quality of the weld overlay when depositing Monel alloy on the irregular surface of stainless steel. Therefore, depositing Monel alloy on its surface is technically very difficult. Summary of the Invention

[0007] The purpose of this invention is to address the aforementioned problems in the prior art by providing a method for welding the inner hole of a rectangular spline short bushing that can effectively guarantee the quality of the weld overlay.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows: A method for welding the inner hole of a rectangular spline short bushing, the method comprising: firstly welding a transition layer onto the surface of the spline inner hole, then machining the transition layer, and after passing the dye penetrant testing, welding a fusion layer onto the surface of the transition layer, wherein the welding wires used for the transition layer and the fusion layer are SNi2061 and SNi4060 respectively, and the welding process of the transition layer and the fusion layer includes the following steps in sequence: Step A: Place the rectangular spline short shaft sleeve on the tire rolling frame; Step B: Adjust the position of the rectangular spline using the rolling frame so that the root R-angle of a certain spline tooth is in the boat-shaped weld position, and then perform overlay welding on the R-angle. Step C: For each plane of the above spline teeth, first adjust the position of the rectangular spline using the roller frame so that a certain plane is in the flat welding position, and then perform the overlay welding on that plane. Step D: Complete the welding of the remaining spline teeth according to steps BC.

[0009] When overlaying the transition layer, a mixture of argon (75% by volume) and helium (25% by volume) is used as the shielding gas. The welding parameters include: welding current 140-160A, voltage 23-26V, welding speed 40-50cm / min, and gas flow rate 20-25L / min.

[0010] When depositing the weld overlay, a mixture of 75% argon and 25% helium by volume is used as the shielding gas. The welding parameters include: welding current 140-160A, voltage 23-26V, welding speed 40-50cm / min, and gas flow rate 20-25L / min.

[0011] During the welding process, the interlayer temperature is controlled at less than or equal to 60℃.

[0012] In the aforementioned welding method, after the weld overlay layer is completed, the workpiece is placed in an annealing furnace for annealing treatment, and then the workpiece is removed from the furnace and air-cooled to room temperature. The annealing treatment includes: the furnace temperature does not exceed 100°C when the workpiece enters the furnace, the workpiece is heated at a rate of 150°C / hour after entering the furnace, and the furnace temperature is held at 490-510°C for 4-5 hours.

[0013] The welding direction of the overlay is from the inside of the spline towards its end.

[0014] During the welding process, the overlap between two adjacent weld beads is 1 / 3 to 1 / 2 of the weld bead width.

[0015] The thickness of the transition layer before and after machining is 1.8-2.1 mm and 1-1.3 mm, respectively, and the combined thickness of the transition layer and the weld layer after machining is 5 mm.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention discloses a method for overlaying the inner hole of a rectangular spline short bushing. The overlaying process for the transition layer and the weld layer includes: first, adjusting the position of the rectangular spline so that the root radius (R-angle) of a certain spline tooth is in a boat-shaped weld position; then, overlaying welding is performed at the R-angle; next, for each plane of the spline tooth, the position of the rectangular spline is adjusted so that the plane is in a flat weld position, followed by overlaying welding of the plane. This method, combined with the structural characteristics of the rectangular spline, designs a welding process for overlaying Monel alloy on 0Cr16Ni5Mo material. This special welding process ensures that the performance of the overlay layer meets the relevant technical requirements, effectively guaranteeing the quality of the overlay layer. Therefore, the present invention effectively guarantees the quality of the overlay layer. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a rectangular spline short shaft sleeve.

[0018] Figure 2 This is a schematic diagram of the welding process in Example 1.

[0019] Figure 3 This is a schematic diagram of the welding direction in Example 1. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0021] See Figure 1 A method for welding the inner hole of a rectangular spline short bushing, the method comprising: firstly welding a transition layer onto the surface of the spline inner hole, then machining the transition layer, and after passing the dye penetrant testing, welding a fusion layer onto the surface of the transition layer, wherein the welding wires used for the transition layer and the fusion layer are SNi2061 and SNi4060 respectively, and the welding process of the transition layer and the fusion layer includes the following steps in sequence: Step A: Place the rectangular spline short shaft sleeve on the tire rolling frame; Step B: Adjust the position of the rectangular spline using the rolling frame so that the root R-angle of a certain spline tooth is in the boat-shaped weld position, and then perform overlay welding on the R-angle. Step C: For each plane of the above spline teeth, first adjust the position of the rectangular spline using the roller frame so that a certain plane is in the flat welding position, and then perform the overlay welding on that plane. Step D: Complete the welding of the remaining spline teeth according to steps BC.

[0022] When overlaying the transition layer, a mixture of argon (75% by volume) and helium (25% by volume) is used as the shielding gas. The welding parameters include: welding current 140-160A, voltage 23-26V, welding speed 40-50cm / min, and gas flow rate 20-25L / min.

[0023] When depositing the weld overlay, a mixture of 75% argon and 25% helium by volume is used as the shielding gas. The welding parameters include: welding current 140-160A, voltage 23-26V, welding speed 40-50cm / min, and gas flow rate 20-25L / min.

[0024] During the welding process, the interlayer temperature is controlled at less than or equal to 60℃.

[0025] In the aforementioned welding method, after the weld overlay layer is completed, the workpiece is placed in an annealing furnace for annealing treatment, and then the workpiece is removed from the furnace and air-cooled to room temperature. The annealing treatment includes: the furnace temperature does not exceed 100°C when the workpiece enters the furnace, the workpiece is heated at a rate of 150°C / hour after entering the furnace, and the furnace temperature is held at 490-510°C for 4-5 hours.

[0026] The welding direction of the overlay is from the inside of the spline towards its end.

[0027] During the welding process, the overlap between two adjacent weld beads is 1 / 3 to 1 / 2 of the weld bead width.

[0028] The thickness of the transition layer before and after machining is 1.8-2.1 mm and 1-1.3 mm, respectively, and the combined thickness of the transition layer and the weld layer after machining is 5 mm.

[0029] The principle of this invention is explained as follows: This invention provides a method for internal hole surfacing welding of a rectangular spline short bushing. This method, on the one hand, takes into account the structural characteristics of the rectangular spline, employing a method where the root radius (R-angle) of the spline teeth is surfacing at a boat-shaped welding position, and the planes of the spline teeth are surfacing at a flat welding position. On the other hand, for the surfacing process, a mixed gas consisting of 75% argon and 25% helium by volume is used as the shielding gas to ensure the forming quality of the surfacing layer. Simultaneously, relatively small welding parameters are selected for the surfacing operation, and the interpass temperature is strictly controlled during the surfacing process. After surfacing, the workpiece is annealed to reduce welding stress. Based on these measures, the quality of the surfacing layer is effectively improved, ensuring its performance meets relevant technical requirements. Example

[0030] See Figure 1 A method for welding the inner hole of a rectangular spline short bushing, the method specifically being: First, a 2mm thick transition layer is deposited on the inner surface of the spline hole. Then, the transition layer is machined to 1.3mm. After passing the dye penetrant inspection, a weld bead is deposited on the surface of the transition layer, so that the sum of the thicknesses of the transition layer and the weld bead is greater than 5mm. Then, the workpiece is placed in an annealing furnace for annealing treatment. The welding conditions for the transition layer are as follows: 1.2mm diameter welding wire SNi2061, a mixed gas consisting of 75% argon and 25% helium by volume as the protective gas, jetting, nozzle diameter 17mm, DC reverse polarity, welding current 140-160A, voltage 23-26V, welding speed 40-50cm / min, and gas flow rate 20-25L / min. The welding conditions for the fused layer are as follows: 1.2 mm diameter welding wire SNi4060, a mixed gas consisting of 75% argon and 25% helium by volume as the shielding gas, jetting, nozzle diameter 17 mm, DC reverse polarity, welding current 140-160 A, voltage 23-26 V, welding speed 40-50 cm / min, gas flow rate 20-25 L / min, and interpass temperature less than or equal to 60 °C. The welding process for the transition layer and the weld overlay layer is carried out in sequence according to the following steps: 1. Clean each surface of the spline teeth with alcohol; 2. Place the rectangular splined short shaft sleeve on the tire rolling frame; 3. See Figure 2 In (a), the position of the rectangular spline is adjusted by using a tire roller frame so that the root R-angle of a certain spline tooth is in the boat-shaped welding position, and then the R-angle is welded. 4. See Figure 2 In step (b), the position of the rectangular spline is adjusted by using a tire roller frame so that the side of the spline teeth is in the flat welding position, and then side welding is performed. 5. See Figure 2 In step (c), the position of the rectangular spline is adjusted by using a tire roller frame so that the upper surface of the spline teeth is in the flat welding position, and then the upper surface is overlaid with weld. 6. All other spline teeth shall be welded according to steps 3-5 until the welding is completed; In the above-described welding process, the welding direction is from the inside of the spline towards its end (see...). Figure 3 The overlap between two adjacent weld beads is 2 / 5 of the weld bead width; The annealing process includes: the furnace temperature is 80°C when the workpiece is put into the furnace, the workpiece is heated at a rate of 150°C / hour after it is put into the furnace, the furnace temperature is raised to 500°C and held for 5 hours, and then the workpiece is taken out of the furnace and air-cooled to room temperature.

[0031] The weld layer of a batch of workpieces obtained using the method described in Example 1 was subjected to quality inspection, and the results are as follows: The weld overlay was subjected to dye penetrant testing (NB / T47013-2015), and passed Level I.

[0032] Tensile test results show that the yield strength of the weld overlay cladding metal is 300-316 MPa, which meets the design yield strength ≥286 MPa.

[0033] Hardness test results show that the hardness at 5mm from the weld overlay fusion line is less than 185HB, which meets the design requirements.

[0034] The shear test results show that the shear strength of the weld overlay is 503-558 MPa, which meets the requirement of a shear strength greater than 159 MPa.

[0035] The welding deformation is less than 1mm, which meets the design requirements.

Claims

1. A method for welding the inner hole of a rectangular spline short bushing, characterized in that: The welding method includes: first, welding a transition layer onto the surface of the spline inner hole; then, machining the transition layer; after passing the dye penetrant testing, welding a fusion layer onto the surface of the transition layer; wherein the welding wires used for the transition layer and the fusion layer are SNi2061 and SNi4060, respectively; and the welding process for the transition layer and the fusion layer includes the following steps in sequence: Step A: Place the rectangular spline short shaft sleeve on the tire rolling frame; Step B: Adjust the position of the rectangular spline using the rolling frame so that the root R-angle of a certain spline tooth is in the boat-shaped weld position, and then perform overlay welding on the R-angle. Step C: For each plane of the above spline teeth, first adjust the position of the rectangular spline using the roller frame so that a certain plane is in the flat welding position, and then perform the overlay welding on that plane. Step D: Complete the welding of the remaining spline teeth according to steps BC.

2. The method for welding the inner hole of a rectangular spline short bushing according to claim 1, characterized in that: When overlaying the transition layer, a mixture of argon with a volume content of 75% and helium with a volume content of 25% is used as the shielding gas. The welding parameters include: welding current 140-160A, voltage 23-26V, welding speed 40-50cm / min, and gas flow rate 20-25L / min. When depositing the weld overlay, a mixture of 75% argon and 25% helium by volume is used as the shielding gas. The welding parameters include: welding current 140-160A, voltage 23-26V, welding speed 40-50cm / min, and gas flow rate 20-25L / min.

3. The method of claim 1 or 2, wherein: During the welding process, the interlayer temperature is controlled to be less than or equal to 60℃.

4. The method of claim 1 or 2, wherein: In the aforementioned welding method, after the weld overlay layer is completed, the workpiece is placed in an annealing furnace for annealing treatment, and then the workpiece is removed from the furnace and air-cooled to room temperature. The annealing treatment includes: the furnace temperature does not exceed 100°C when the workpiece enters the furnace, the workpiece is heated at a rate of 150°C / hour after entering the furnace, and the furnace temperature is held at 490-510°C for 4-5 hours.

5. The method of claim 1 or 2, wherein: The welding direction of the overlay is from the inside of the spline towards its end.

6. The method of claim 1 or 2, wherein: During the welding process, the overlap between two adjacent weld beads is 1 / 3 to 1 / 2 of the weld bead width.

7. The method of claim 1 or 2, wherein: The thickness of the transition layer before and after machining is 1.8-2.1 mm and 1-1.3 mm, respectively, and the combined thickness of the transition layer and the weld layer after machining is 5 mm.

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