A welding process for a cyclone nozzle housing assembly

Abstract

The application provides a kind of welding process method of cyclone nozzle shell assembly, it is related to welding technical field, including the following steps: adopting spectral analyzer to verify shell and nozzle material, on its surface treatment;By the positioning fixture of the shaft center positioning rod and inner fixed plate and radially compact radial force plate, shell and nozzle are clamped and fixed;Adopting multilayer multichannel digitized pulse MIG welding;Shell and nozzle assembly after welding are placed into aging furnace;The shell and nozzle assembly after welding are detected.The shaft center positioning rod, inner fixed plate and radially compact radial force plate realize the high-precision positioning of shell and nozzle, accurately adjust radial force plate, strictly control coaxiality to ≤0.05mm, the precision is improved, the stability of medium flow is greatly enhanced, solves the positioning precision difference when positioning by using conventional fixture, shell and nozzle coaxiality deviation exceeds 0.15mm, causes the problem of medium flow disorder, separation efficiency decline.

Description

Technical Field

[0001] This invention relates to the field of welding technology, and in particular to a welding process method for a hydrocyclone nozzle housing assembly. Background Technology

[0002] As a high-efficiency separation device, the core component of the hydrocyclone, the nozzle housing assembly, is welded from the housing and the nozzle. This assembly needs to withstand the scouring of high-pressure media and periodic vibration, so the requirements for the sealing performance, tensile strength and fatigue resistance of the weld are extremely high.

[0003] In existing technologies, when welding the nozzle and housing components of a hydrocyclone, the positioning accuracy is poor when using conventional fixtures, and the coaxiality deviation between the housing and the nozzle exceeds 0.15mm, resulting in turbulent medium flow and reduced separation efficiency. The heat input of manual arc welding is unstable, causing severe thermal deformation. Radial deformation occurs in the housing after welding, which requires subsequent correction, increasing process costs. Martensite structure is easily generated when welding dissimilar steels, resulting in low weld reliability, excessive weld hardness, and easy cracking under vibration conditions, leading to a short component service life. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a welding process method for a hydrocyclone nozzle housing assembly, thereby solving the problems mentioned in the background section.

[0005] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0006] This invention relates to a welding process method for a hydrocyclone nozzle housing assembly, specifically including the following steps:

[0007] 1. Component pretreatment: The materials of the housing and nozzle are verified using a spectral analyzer, and their surfaces are then treated.

[0008] Second, the housing and nozzle are clamped and fixed by a positioning fixture with a axial positioning rod and an inner fixing plate and a radially pressing radial force plate;

[0009] Third, multi-layer, multi-pass digital pulse MIG welding is adopted, using ER309MoL welding wire, and welding is performed in the order of root pass, fill pass, and cover pass.

[0010] Fourth, place the welded shell and nozzle assembly into an aging furnace and cool them in the furnace to below 80°C, then remove them from the furnace and air cool them.

[0011] Fifth, conduct visual inspection, ultrasonic testing, penetrant testing, and mechanical property testing on the welded shell and nozzle assembly, and record the welding parameters to form an electronic file.

[0012] Furthermore, the chemical composition of the housing and nozzle detected by the spectrometer in step one is as follows: the carbon content of the housing is ≤0.20%, the chromium content is ≥1.0%, and the chromium content of the nozzle is ≥16% and the nickel content is ≥10%. The surface treatment of the housing and nozzle involves acetone degreasing and soaking for 5-8 minutes, followed by quartz sandblasting at a pressure of 0.6-0.8MPa to achieve a rust removal grade of Sa2.5 and a surface roughness of Ra3.2-Ra6.3μm. Then, the welded end faces of the housing and nozzle are chamfered using an angle grinder with a chamfer angle of 30°±5° and a chamfer width of 2-3mm.

[0013] Furthermore, after the positioning fixture in step two fixes the housing and nozzle, its axial tolerance grade is H7. Then, the radial runout of the housing and nozzle is monitored by the displacement sensor on the positioning ring. The radial force plate is adjusted to make the coaxiality ≤0.05mm, and a copper shim with a thickness of 0.5-1.0mm is inserted between the welding end faces.

[0014] Furthermore, the digital pulse MIG welding machine in step three is configured with... A mixed shielding gas is used. The chromium-nickel content of the welding wire ER309MoL is matched to that of dissimilar steels. The presence of Mo enhances resistance to pitting corrosion. During welding, the parameters for different welding passes are as follows: For the root pass, the pulse current is 180-200A, the pulse voltage is 22-24V, the welding speed is 8-10cm / min, the heat input is 0.8-1.0kJ / cm, and the interpass temperature must be controlled at ≤150℃. The filler weld is divided into filler weld one and filler weld two. The parameters for both are the same: pulse current of 220-240A, pulse voltage of 24-26V, welding speed of 10-12cm / min, heat input of 1.2-1.4kJ / cm, and interpass temperature of ≤250℃. For cover pass welding, the pulse current is 200-220A, pulse voltage is 23-25V, welding speed is 9-11cm / min, heat input is 1.0-1.2kJ / cm, and interpass temperature of ≤200℃.

[0015] Furthermore, in step three, the welding operation uses a short-circuit transition method for the root pass, welding from the nozzle end to the shell end. The fill and cover passes use a spray transition method. After each pass, the slag is cleaned with a wire brush. During the welding process, an infrared thermometer is used to monitor the interpass temperature in real time. If the temperature exceeds the limit, the welding is suspended and the temperature is allowed to cool naturally to the set temperature.

[0016] Furthermore, in step four, the heating rate of the aging furnace is controlled at 50℃ / h, and the temperature is raised to 220℃±10℃ and held for 2.5-3h. The residual welding stress is eliminated through low-temperature aging, and the furnace is cooled and removed from the furnace.

[0017] Furthermore, the outer tube inspection requirements in step five are as follows: the weld reinforcement should be 2-3mm, free from defects such as undercut, porosity, and cracks, and conform to the requirements of GB / T19418-2019. Ultrasonic testing should be conducted according to JB / T4730.3-2020 standard to detect internal weld defects, with equivalent defects ≤ Φ2mm. Penetrant testing (PT) should be conducted according to JB / T4730.5-2020 standard to detect surface and near-surface defects of the weld, with no linear defects. For mechanical property testing, two pieces should be sampled from each batch for weld tensile testing, hardness testing, and bending testing. The welding current, voltage, speed, shielding gas flow rate, and other parameters should be recorded to form an electronic archive.

[0018] Furthermore, the positioning fixture in step two includes: a fixed frame, which is a rectangular frame structure, and two positioning support plates are installed on the top of the fixed frame; a drive motor is installed at one end of the top of the fixed frame, and a rotating rod is installed on the output end of the drive motor; the rotating rod is rotatably installed on the side of the two positioning support plates; two guide rods are installed between the two positioning support plates; guide blocks are slidably installed on the outer side of the two guide rods; positioning rings are slidably installed on the inner side of the two guide blocks; the positioning rings are annular structures, a displacement sensor is installed on the inner side of the positioning rings, and three evenly distributed drive cylinders are installed on the outer side of the positioning rings, with radial force plates installed on the output ends of the drive cylinders; the radial force plates are arc-shaped structures, and rollers are rotatably installed on the side ends of the radial force plates.

[0019] Furthermore, a support bracket is installed at the top edge of the fixed frame; a direction guide component is slidably installed on the top inner side of the support bracket; a drive component is installed at the bottom of the direction guide component; a welding gun is installed at the bottom of the drive component; a welding machine component is installed on the rear side of the fixed frame; a conveying component is installed on the welding machine component; and the conveying component is connected to the drive component.

[0020] Furthermore, a rotating wheel is rotatably mounted at the middle position of each of the two positioning support plates; a chain assembly is mounted on the outer side of each of the two rotating wheels, and the outer side of the two rotating wheels is connected to the outer side of the rotating rod through the chain assembly; a central positioning rod is slidably mounted through the middle position of each rotating wheel; a limiting protrusion is provided on the outer side of the central positioning rod, and an adjusting threaded rod is rotatably mounted inside the central positioning rod; a center plate is mounted on the side end of the adjusting threaded rod; the nozzle and housing assembly of the hydrocyclone are annularly fitted on the outer side of the central positioning rod, and a support plate one is rotatably mounted on the side end of the central positioning rod; a support plate two is rotatably mounted on the side end of the center plate; an inner fixing plate is rotatably mounted on the side ends of the support plate one and the support plate two, wherein the outer side of the inner fixing plate has an arc-shaped structure.

[0021] This invention provides a welding process for a hydrocyclone nozzle housing assembly, which has the following advantages:

[0022] In use, this invention employs a dedicated positioning fixture, a central positioning rod, an inner fixing plate, and a radial clamping force plate to achieve high-precision positioning of the housing and the nozzle. A displacement sensor on the positioning ring monitors radial runout in real time, precisely adjusting the radial force plate to strictly control coaxiality to ≤0.05mm. This improved precision significantly enhances the stability of media flow, improving it by 25% compared to traditional processes. This effectively increases the separation efficiency of the hydrocyclone by 15%-20%, significantly improving product performance.

[0023] During the welding process, this invention utilizes digital pulsed MIG welding technology, which enables precise control of heat input and effectively avoids the thermal deformation problems caused by unstable heat input in manual arc welding. Simultaneously, inserting a 0.5-1.0mm thick copper shim between the welding ends absorbs some heat, further reducing thermal deformation. The radial deformation of the welded shell is ≤0.3mm, a significant reduction that eliminates the need for subsequent straightening processes, directly lowering production costs by 10% and improving production efficiency.

[0024] ER309MoL welding wire is used for welding. The chromium and nickel content of the welding wire is matched with that of dissimilar steel, and the Mo element it contains can improve the resistance to pitting corrosion. Low-temperature aging treatment eliminates residual welding stress and avoids the decrease in hardness of wear-resistant steel caused by high temperature. The weld tensile strength is tested to be ≥500MPa, which effectively improves the reliability of the weld and significantly increases the service life of the components to 18-24 months, which is 2-3 times that of traditional processes. This greatly reduces the frequency of equipment replacement and maintenance costs, bringing significant economic benefits to users. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments will be briefly described below.

[0026] The accompanying drawings described below are only related to some embodiments of the invention and are not intended to limit the invention.

[0027] In the attached diagram:

[0028] Figure 1 A welding process flow diagram of the present invention is shown;

[0029] Figure 2 A schematic diagram of the overall structure of the present invention is shown;

[0030] Figure 3 A three-dimensional structural diagram of the support bracket of the present invention is shown;

[0031] Figure 4 A three-dimensional structural diagram of the guide rod of the present invention is shown;

[0032] Figure 5A three-dimensional structural diagram of the positioning ring of the present invention is shown;

[0033] Figure 6 This diagram shows the internal fixing plate, support plate one, and support plate two of the present invention in their unfolded states.

[0034] Figure 7 This diagram shows the folded state of the inner fixing plate, the first support plate, and the second support plate of the present invention.

[0035] Figure 8 A schematic cross-sectional view of the rotating wheel structure of the present invention is shown;

[0036] Figure 9 A cross-sectional view of the axial positioning rod of the present invention is shown.

[0037] List of reference numerals

[0038] 1. Fixed frame; 101. Positioning support plate; 102. Rotating rod; 103. Guide rod; 104. Guide block; 105. Positioning ring; 106. Radial force application plate; 107. Roller;

[0039] 2. Support bracket; 201. Directional guide assembly; 202. Drive assembly; 203. Welding torch; 204. Welding machine assembly; 205. Conveying assembly;

[0040] 3. Rotating wheel; 301. Axis positioning rod; 302. Adjusting threaded rod; 303. Center plate; 304. Support plate one; 305. Support plate two; 306. Inner fixing plate. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the described embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] Please refer to Figures 1 to 9 :

[0043] Example 1: This invention proposes a welding process method for a hydrocyclone nozzle housing assembly, comprising the following steps:

[0044] 1. Component pretreatment: The materials of the housing and nozzle are verified using a spectral analyzer, and their surfaces are then treated.

[0045] Second, the housing and nozzle are clamped and fixed by a positioning fixture with a axial positioning rod 301 and an inner fixing plate 306 and a radially pressing radial force plate 106.

[0046] Third, multi-layer, multi-pass digital pulse MIG welding is adopted, using ER309MoL welding wire, and welding is performed in the order of root pass, fill pass, and cover pass.

[0047] Fourth, place the welded shell and nozzle assembly into an aging furnace and cool them in the furnace to below 80°C, then remove them from the furnace and air cool them.

[0048] Fifth, conduct visual inspection, ultrasonic testing, penetrant testing, and mechanical property testing on the welded shell and nozzle assembly, and record the welding parameters to form an electronic file;

[0049] The chemical composition of the housing and nozzle detected by the spectrometer in step one is as follows: the housing has a carbon content ≤0.20% and a chromium content ≥1.0%, while the nozzle has a chromium content ≥16% and a nickel content ≥10%, to avoid embrittlement phases during welding of dissimilar steels. The surfaces of the housing and nozzle are treated by acetone degreasing and soaking for 5-8 minutes to remove oil, followed by quartz sandblasting at a pressure of 0.6-0.8 MPa to achieve a rust removal grade of Sa2.5 and a surface roughness of Ra3.2-Ra6.3 μm, enhancing weld fusion. Finally, the welded ends of the housing and nozzle are ground using an angle grinder. The chamfering process involves a chamfer angle of 30°±5° and a chamfer width of 2-3mm to prevent incomplete weld penetration. In step two, after the positioning fixture fixes the housing and nozzle, its axial tolerance grade is H7. The radial runout of the housing and nozzle is then monitored by a displacement sensor on the positioning ring 105. The radial force plate 106 is adjusted to ensure coaxiality ≤0.05mm. A 0.5-1.0mm thick copper shim is inserted between the welding end faces to ensure a uniform welding gap. The copper shim also absorbs some heat, reducing thermal deformation. Step three involves a digital pulse MIG welding machine configured with… A mixed shielding gas is used. The chromium-nickel content of the welding wire ER309MoL is matched to that of dissimilar steels. The presence of Mo enhances resistance to pitting corrosion. During welding, the parameters for different welding passes are as follows: For the root pass, the pulse current is 180-200A, the pulse voltage is 22-24V, the welding speed is 8-10cm / min, the heat input is 0.8-1.0kJ / cm, and the interpass temperature must be controlled at ≤150℃. The filler weld is divided into filler weld one and filler weld two, with identical parameters: pulse current 220-240A, pulse voltage 24V / cm. -26V, welding speed 10-12cm / min, heat input 1.2-1.4kJ / cm, interpass temperature ≤250℃; for cover welding, pulse current 200-220A, pulse voltage 23-25V, welding speed 9-11cm / min, heat input 1.0-1.2kJ / cm, interpass temperature ≤200℃; in step three, the root pass welding uses a short-circuit transfer method, welding from the nozzle end to the shell end to avoid diffusion of carbon elements from the wear-resistant steel to the stainless steel; the fill and cover welds use spray welding. The transition process involves cleaning slag with a wire brush after each weld to ensure no slag inclusions between layers. During welding, an infrared thermometer is used to monitor the inter-layer temperature in real time; welding is paused if the temperature exceeds the limit, and the material is allowed to cool naturally to the set temperature. In step four, the aging furnace heating rate is controlled at 50℃ / h to avoid secondary deformation caused by sudden temperature increases. The temperature is raised to 220℃±10℃ and held for 2.5-3 hours to eliminate residual welding stress through low-temperature aging, while simultaneously preventing a decrease in the hardness of the wear-resistant steel due to high temperatures. The steel is then cooled in the furnace to prevent thermal stress caused by excessively rapid cooling. Step five, the outer tube inspection requirements, include weld residue... The weld should be 2-3mm high, free from defects such as undercut, porosity, and cracks, and meet the requirements of GB / T19418-2019. Ultrasonic testing should be performed according to JB / T4730.3-2020 standard to detect internal defects in the weld, with equivalent defects ≤ Φ2mm. Penetrant testing (PT) should be performed according to JB / T4730.5-2020 standard to detect surface and near-surface defects in the weld, with no linear defects. For mechanical property testing, two pieces should be sampled from each batch for tensile testing, hardness testing, and bending testing of the weld. The welding current, voltage, speed, shielding gas flow rate, and other parameters should be recorded to form an electronic archive.

[0050] In Example 2, based on Example 1, the positioning fixture includes a fixed frame 1, which is a rectangular frame structure, and two positioning support plates 101 are installed on the top of the fixed frame 1; a drive motor is installed at one end of the top of the fixed frame 1, and a rotating rod 102 is installed on the output end of the drive motor; the rotating rod 102 is rotatably mounted on the side of the two positioning support plates 101; two guide rods 103 are installed between the two positioning support plates 101; and guide blocks 104 are slidably installed on the outer side of each of the two guide rods 103. Positioning rings 105 are slidably installed on the inner sides of the two guide blocks 104; the positioning rings 105 are annular structures, and displacement sensors are installed on the inner side of the positioning rings 105, while three evenly distributed drive cylinders are installed on the outer side of the positioning rings 105, with radial force plates 106 installed on the output ends of the drive cylinders; the radial force plates 106 are arc-shaped structures, and rollers 107 are rotatably installed on the side ends of the radial force plates 106; a support bracket 2 is installed at the top edge of the fixed frame 1; and a slidably installed support bracket 2 is installed on the inner top of the support bracket 2. Directional guide assembly 201; a drive assembly 202 is mounted on the bottom of the directional guide assembly 201; a welding torch 203 is mounted on the bottom of the drive assembly 202; a welding machine assembly 204 is mounted on the rear side of the fixed frame 1; a conveyor assembly 205 is mounted on the welding machine assembly 204; the conveyor assembly 205 is connected to the drive assembly 202; rotating wheels 3 are rotatably mounted at the middle positions of the two positioning support plates 101; chain assemblies are mounted on the outer sides of the two rotating wheels 3, and the outer sides of the two rotating wheels 3 are connected to the rotating rod 102 through the chain assemblies. The outer transmission connection is as follows: A shaft positioning rod 301 is slidably mounted through the middle position of the rotating wheel 3; a limiting protrusion is provided on the outer side of the shaft positioning rod 301, and an adjusting threaded rod 302 is rotatably mounted inside the shaft positioning rod 301; a center plate 303 is mounted on the side end of the adjusting threaded rod 302; the nozzle and housing assembly of the cyclone separator are annularly sleeved on the outer side of the shaft positioning rod 301, and a support plate 304 is rotatably mounted on the side end of the shaft positioning rod 301; a support plate 305 is rotatably mounted on the side end of the center plate 303.An inner fixing plate 306 is rotatably mounted on the side ends of support plate 1 304 and support plate 2 305. The outer side of the inner fixing plate 306 has an arc-shaped structure. During the welding of the hydrocyclone shell and nozzle assembly, the axial positioning rod 301 is pulled outward from the middle position of the rotating wheel 3. The surface-treated shell and nozzle are placed on the outside of the two axial positioning rods 301. A copper shim is placed between the welding parts of the shell and the nozzle. The adjusting threaded rod 302 is rotated inside the axial positioning rod 301 to move the center plate 303. Support plate 1 304 and support plate 2 305 drive the inner fixing plate 306 to unfold and move outward, so that multiple inner fixing plates 306 are respectively installed on the shell and nozzle. On the inner side of the nozzle, the sliding guide block 104 on the outer side of the guide rod 103 drives the positioning ring 105 to move, so that the positioning ring 105 drives the three radial force plates 106 to be at the weld seam of the housing and the nozzle. The displacement sensor on the inner side of the positioning ring 105 detects the weld seam. The drive cylinder drives the radial force plates 106 to apply radial pressure to the weld seam. The friction of the rollers 107 at both ends of the radial force plates 106 in contact with them makes the weld seam gap aligned. The direction guide assembly 201 moves along the inner side of the top of the support bracket 2. The drive assembly 202 adjusts the position of the welding gun 203 at the bottom. The welding machine assembly 204 provides ER309MoL welding wire and through the conveying assembly 205. The nozzle and housing assembly are welded using a mixed protective gas, with the following steps performed sequentially: root pass, fill pass 1, fill pass 2, and cover pass. A drive motor at the top of the fixed frame 1 drives the rotating rod 102 to rotate. The outer side of the rotating rod 102 drives two rotating wheels 3 to rotate on the side of the positioning support plate 101 via two chain sets. The rotating wheels 3 drive the inner fixing plate 306 via the axial positioning rod 301, which in turn drives the housing and nozzle to rotate. The positioning ring 105 rotates between the guide blocks 104, thereby moving the weld seam to facilitate continuous welding by the welding torch 203. After welding, the nozzle and housing assembly are placed in an aging furnace for cooling and then inspected to obtain a high-quality hydrocyclone nozzle and housing assembly.

[0051] Example 3, based on Example 1, takes a Φ150mm hydrocyclone nozzle housing assembly used in mining as an example. The housing is made of NM500 wear-resistant steel, and the nozzle is made of 316L stainless steel. Welding is performed using this process. Spectrometer analysis confirms that the housing has a carbon content of 0.18% and a chromium content of 1.2%, while the nozzle has a chromium content of 17% and a nickel content of 12%. After degreasing by soaking in acetone for 6 minutes, the assembly is sandblasted to Sa2.5 grade using 0.7MPa quartz sand. An angle grinder is used to chamfer the weld joint to 30° with a width of 2.5mm. The treated nozzle and housing are then installed on a special positioning fixture, with a 0.8mm thick copper shim inserted. The inner fixing plate 306 fixes the inner side of the fixture, and the radial force plate 106 fixes the outer side of the weld, ensuring a centering shaft tolerance of H7 and a fit clearance of 0.03mm. The displacement sensor inside the positioning ring 105 monitors radial runout ≤0.04mm. Then, using… The protective gas flow rate is 20L / min. The root pass welding speed is 190A / 23V / 9cm / min, the fill pass welding speed is 230A / 25V / 11cm / min, and the cap pass welding speed is 210A / 24V / 10cm / min. The interpass temperature is controlled between 150-250℃. After welding, the weld is placed in an aging furnace and heated to 220℃ at 50℃ / h, held for 2.8h, and then cooled to 75℃ before being inspected. The inspection standards are: weld reinforcement of 2.5mm, no appearance defects, ultrasonic testing with no defects ≥2mm, penetrant testing with no surface defects, and sampling tensile testing with a tensile strength of 520MPa, a hardness of 260HV, and no cracks after bending 180°. The welding parameters are uploaded to the cloud in real time to form a traceable archive. The produced component has been tested on-site and has been continuously operated for 20 months under a medium pressure of 1.8MPa without weld leakage or cracks. The hydrocyclone separation efficiency is stable at over 92%, meeting the requirements for industrial use.

[0052] The working principle of this embodiment is as follows: The surface-treated housing and nozzle are placed on the outside of the two axial positioning rods 301. The copper shim is placed between the welding parts of the housing and the nozzle. Rotating the adjusting threaded rod 302 drives the center plate 303 to move. The support plate 1 304 and the support plate 2 305 drive the inner fixing plate 306 to unfold and move outward and install it on the inside of the housing and the nozzle. The sliding guide block 104 on the outside of the guide rod 103 drives the positioning ring 105 to move. The positioning ring 105 drives the three radial force plates 106 to be fixed at the weld seam of the housing and the nozzle. After the welding gun 203 is adjusted in position by the directional guide component 201 and the drive component 202, it welds the nozzle and housing assembly. After the welding is completed, the nozzle and housing assembly is placed in the aging furnace for cooling and then tested to obtain a high-quality hydrocyclone nozzle housing assembly.

[0053] The following points should be noted in this article:

[0054] 1. The accompanying drawings of the embodiments of the present invention only involve the structures involved in the embodiments of the present invention; other structures can refer to general designs.

[0055] 2. Where there is no conflict, the embodiments of the present invention and the features thereof can be combined with each other to obtain new embodiments.

[0056] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A welding process method for a hydrocyclone nozzle housing assembly, characterized in that, Includes the following steps:

1. Component pretreatment: The materials of the housing and nozzle are verified using a spectral analyzer, and their surfaces are then treated. Second, the housing and nozzle are clamped and fixed by a positioning fixture, wherein the positioning fixture includes: a fixed frame (1), the top of which is equipped with two positioning support plates (101); a drive motor is installed at one end of the top of the fixed frame (1), and a rotating rod (102) is installed on the output end of the drive motor; the rotating rod (102) is rotatably mounted on the side of the two positioning support plates (101); two guide rods (103) are installed between the two positioning support plates (101); the outer sides of the two guide rods (103) are slidably mounted. The system is equipped with guide blocks (104); positioning rings (105) are slidably installed on the inner sides of the two guide blocks (104); displacement sensors are installed on the inner sides of the positioning rings (105), and three evenly distributed drive cylinders are installed on the outer sides of the positioning rings (105), with radial force plates (106) installed on the output ends of the drive cylinders; rollers (107) are rotatably installed on the side ends of the radial force plates (106); rotating wheels (3) are rotatably installed at the middle positions of the two positioning support plates (101); chain sets are installed on the outer sides of the two rotating wheels (3). The outer sides of the two rotating wheels (3) are connected to the outer side of the rotating rod (102) via a chain assembly; a slidable shaft positioning rod (301) is mounted through the middle of the rotating wheel (3); a limiting protrusion is provided on the outer side of the shaft positioning rod (301), and an adjusting threaded rod (302) is rotatably mounted inside the shaft positioning rod (301); a center plate (303) is mounted on the side end of the adjusting threaded rod (302); the nozzle and housing assembly of the hydrocyclone are encircled on the outer side of the shaft positioning rod (301), and the side end of the shaft positioning rod (301) is... A support plate 1 (304) is rotatably mounted; a support plate 2 (305) is rotatably mounted on the side end of the center plate (303); an inner fixing plate (306) is rotatably mounted on the side ends of the support plate 1 (304) and the support plate 2 (305); after the positioning fixture fixes the housing and the nozzle, its axial tolerance grade is H7, and then the radial runout of the housing and the nozzle is monitored by the displacement sensor on the positioning ring (105), the radial force plate (106) is adjusted to make the coaxiality ≤0.05mm, and a copper shim with a thickness of 0.5-1.0mm is inserted between the welding end faces; Third, multi-layer, multi-pass digital pulsed MIG welding is employed. The digital pulsed MIG welding machine is equipped with an Ar + 20% CO2 mixed shielding gas. The ER309MoL welding wire has a chromium-nickel content that matches the welding of dissimilar steels, and the inclusion of Mo enhances its resistance to pitting corrosion. Welding is performed in the sequence of root pass, fill pass, and cover pass. The parameters for different welding passes are as follows: For the root pass, the pulse current is 180-200A, the pulse voltage is 22-24V, the welding speed is 8-10cm / min, the heat input is 0.8-1.0kJ / cm, and the interpass temperature must be controlled at ≤150℃; for the fill pass... For filler welds 1 and 2, the parameters are identical: pulse current 220-240A, pulse voltage 24-26V, welding speed 10-12cm / min, heat input 1.2-1.4kJ / cm, and interpass temperature ≤250℃. For capping welds, the pulse current is 200-220A, pulse voltage 23-25V, welding speed 9-11cm / min, heat input 1.0-1.2kJ / cm, and interpass temperature ≤200℃. The root pass weld uses a short-circuit transfer method, welding from the nozzle end to the shell end. The filler and capping welds use a spray transfer method. Fourth, place the welded shell and nozzle assembly into an aging furnace and cool them in the furnace to below 80°C, then remove them from the furnace and air cool them. Fifth, conduct visual inspection, ultrasonic testing, penetrant testing, and mechanical property testing on the welded shell and nozzle assembly, and record the welding parameters to form an electronic file.

2. The welding process method for a hydrocyclone nozzle housing assembly according to claim 1, characterized in that, The chemical composition of the housing and nozzle detected by the spectrometer in step one is as follows: carbon content ≤0.20%, chromium content ≥1.0% for the housing, and chromium content ≥16% and nickel content ≥10% for the nozzle. The surface treatment of the housing and nozzle involves acetone degreasing and soaking for 5-8 minutes, followed by quartz sandblasting at a pressure of 0.6-0.8MPa to achieve a rust removal grade of Sa2.5 and a surface roughness of Ra3.2-Ra6.3μm. Then, the welded end faces of the housing and nozzle are chamfered using an angle grinder with a chamfer angle of 30°±5° and a chamfer width of 2-3mm.

3. The welding process method for a hydrocyclone nozzle housing assembly according to claim 1, characterized in that, In step three, after each weld, the slag is cleaned with a wire brush. During the welding process, an infrared thermometer is used to monitor the interpass temperature in real time. If the temperature exceeds the limit, the welding is suspended and the temperature is allowed to cool naturally to the set temperature.

4. The welding process method for a hydrocyclone nozzle housing assembly according to claim 1, characterized in that, In step four, the heating rate of the aging furnace is controlled at 50℃ / h, and the temperature is raised to 220℃±10℃. The temperature is held for 2.5-3h to eliminate welding residual stress through low-temperature aging. The furnace is then cooled and removed from the furnace.

5. The welding process method for a hydrocyclone nozzle housing assembly according to claim 1, characterized in that, The requirements for the outer tube inspection in step five are as follows: the weld reinforcement should be 2-3mm, with no undercut, porosity, or cracks, and should meet the requirements of GB / T19418-2019. Ultrasonic testing should be conducted according to JB / T4730.3-2020 standard to detect internal weld defects, with equivalent defects ≤ Φ2mm. Penetrant testing (PT) should be conducted according to JB / T4730.5-2020 standard to detect surface and near-surface defects of the weld, with no linear defects. For mechanical property testing, two pieces should be sampled from each batch for weld tensile testing, hardness testing, and bending testing. The welding current, voltage, speed, and shielding gas flow rate parameters should be recorded and compiled into an electronic archive.

6. The welding process method for a hydrocyclone nozzle housing assembly according to claim 1, characterized in that, A support bracket (2) is installed at the top edge of the fixed frame (1); a direction guide component (201) is slidably installed on the top inner side of the support bracket (2); a drive component (202) is installed at the bottom of the direction guide component (201); a welding torch (203) is installed at the bottom of the drive component (202); a welding machine component (204) is installed on the rear side of the fixed frame (1); a conveying component (205) is installed on the welding machine component (204); and the conveying component (205) is connected to the drive component (202).

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