Narrow-channel three-dimensional impeller slotting welding method and narrow-channel three-dimensional impeller

Abstract

This invention discloses a welding method for narrow-channel three-dimensional impellers and a narrow-channel three-dimensional impeller. The welding method includes: turning a blank to form a disc and a cover; milling blades on the disc; milling welding grooves on the cover; and welding the disc and cover together by hand to form the impeller. Therefore, compared with electrical discharge machining (EDM), the manual welding method for processing narrow-channel three-dimensional impellers has a shorter processing cycle and lower processing cost. Furthermore, compared with robotic welding, it allows for real-time adjustment of welding conditions and parameters based on deformation caused during welding to meet the needs of the current welding position, thereby ensuring good welding results, improving impeller performance, and making it suitable for widespread application.

Description

Technical Field

[0001] This invention relates to the field of impeller processing technology, and in particular to a method for slotting and welding a narrow-channel three-dimensional impeller and the narrow-channel three-dimensional impeller. Background Technology

[0002] Narrow-channel ternary impellers, due to their narrow flow channels and numerous blade twists, are typically machined using integral electrical discharge machining (EDM). However, EDM is not very efficient, and it involves several steps, including electrode design, electrode machining, integral impeller EDM, and abrasive flow machining, resulting in a long machining cycle and high costs for each impeller. Summary of the Invention

[0003] In order to solve the above-mentioned problems in the prior art, the purpose of this invention is to provide a method for slotting and welding a narrow-channel three-dimensional impeller and a narrow-channel three-dimensional impeller, so as to shorten the processing cycle and reduce the processing cost of the narrow-channel three-dimensional impeller.

[0004] The technical solution adopted in this invention is as follows:

[0005] A welding process for a narrow-channel three-dimensional impeller includes: machining a blank to form a disc and a cover; milling blades on the disc; milling welding grooves on the cover; and welding the disc and cover together by hand to form the impeller.

[0006] As a preferred embodiment of the present invention, before the step of welding the wheel disk and the wheel cover together by manual welding to form an impeller, the method further includes: pre-assembling the wheel disk with milled blades and the wheel cover with milled welding grooves; fixing the pre-assembled wheel disk and wheel cover to a welding turntable; wherein the welding turntable can drive the pre-assembled wheel disk and wheel cover to move as a whole, so as to adjust the welding position to a flat welding position.

[0007] As a preferred embodiment of the present invention, after the step of fixing the pre-assembled wheel disk and wheel cover to the welding turntable, and before the step of welding the wheel disk and wheel cover together by manual welding to form an impeller, the method further includes: a fixing ring is sleeved on the outer periphery of the wheel disk, and the fixing ring is welded to the wheel disk; the opening ring of the wheel cover is sleeved on the outer periphery of the fixing ring, and the fixing ring is welded to the wheel cover; wherein, the fixing ring is provided with a vent hole, and the vent hole is connected to the flow channel between two adjacent blades.

[0008] As a preferred embodiment of the present invention, the method further includes: heat-treating the welded impeller to eliminate welding stress; and turning the heat-treated impeller to remove the retaining ring and retaining ring, as well as the machining allowance of the impeller disc and the impeller cover to form the finished impeller.

[0009] As a preferred embodiment of the present invention, the step of welding the wheel disc and the wheel cover together by manual welding to form an impeller specifically includes: sealing the bottom by argon arc welding; filling the bottom by electric arc welding; wherein, multiple welding grooves are welded and sealed by symmetrical welding.

[0010] As a preferred embodiment of the present invention, the step of sealing the bottom by argon arc welding specifically includes: preheating the wheel and wheel cover to 150°C to 200°C; welding the bottom of the welding groove by argon arc welding, while simultaneously filling the wheel at the position opposite to the welding position with argon gas; wherein, the diameter of the tungsten electrode for argon arc welding is 2.3mm to 2.8mm, the welding current is 150A to 160A, the purity of the argon gas is 99.80% to 99.99%, and the flow rate of the argon gas is 8L / min to 12L / min.

[0011] As a preferred embodiment of the present invention, the step of filling welding by arc welding specifically includes: using a welding rod with a diameter of 3.2 mm to 4.0 mm and a welding current of 90 A to 160 A to fill the weld groove by arc welding.

[0012] In a preferred embodiment of the present invention, the centerline of the welding groove is arranged opposite to the centerline of the blade; the length of the welding groove is equal to the length of the blade, and the bottom width of the welding groove is 0.4 to 0.6 mm larger than the width of the blade, and the bottom width of the welding groove is smaller than the opening width; the bottom thickness of the welding groove is 1.1 mm to 1.3 mm; wherein, a plurality of first through holes are provided along the length direction of the groove bottom, and the diameter of the first through holes is 0.8 to 1.2 mm larger than the width of the blade.

[0013] As a preferred embodiment of the present invention, the wheel disk with milled blades is provided with a positioning part, and the wheel cover with milled welding grooves is provided with a limiting part; the wheel disk and the wheel cover are pre-assembled by matching the positioning part and the limiting part.

[0014] A narrow-channel three-dimensional impeller is manufactured by the narrow-channel three-dimensional impeller welding process provided in the first aspect embodiment above.

[0015] The beneficial effects of this invention are as follows:

[0016] The narrow-channel three-dimensional impeller slotting welding method and the narrow-channel three-dimensional impeller of the present invention are processed by manual welding. Compared with electrical discharge machining, the processing cycle is short, the processing cost is low, and the application range is wide. Compared with welding robot welding, it can adjust the welding conditions and welding parameters in real time according to the deformation caused by welding during the welding process to meet the needs of the current welding position, thereby ensuring good welding effect, improving the working performance of the impeller, and making it suitable for widespread application. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart of the narrow-channel three-dimensional impeller welding process provided in an embodiment of the present invention;

[0018] Figure 2 This is a partial structural diagram of the wheel cover provided in an embodiment of the present invention before welding;

[0019] Figure 3 This is a partial structural diagram of the wheel before welding provided in an embodiment of the present invention;

[0020] Figure 4 This is a partial structural diagram of the wheel and wheel cover provided in an embodiment of the present invention before welding;

[0021] Figure 5 This is a partial structural diagram of the wheel and wheel cover fixed to the welding turntable according to an embodiment of the present invention;

[0022] Figure 6 This is a partial structural schematic diagram of the fixing ring provided in an embodiment of the present invention;

[0023] Figure 7 This is a partial structural schematic diagram of the fixing ring provided in an embodiment of the present invention.

[0024] Among them, 110-wheel cover; 111-welding groove; 112-groove bottom; 113-limiting part; 120-wheel disc; 121-blade; 122-positioning part; 130-fixing ring; 131-mounting hole; 140-fixing ring; 141-positioning surface. Detailed Implementation

[0025] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0026] The following reference Figures 1 to 7This invention describes a method for slotting and welding a narrow-channel three-dimensional impeller and a narrow-channel three-dimensional impeller according to some embodiments of the present invention. Specifically, the narrow-channel three-dimensional impeller welding method is used to manufacture finished narrow-channel three-dimensional impellers. In one possible embodiment provided by the present invention, the narrow-channel three-dimensional impeller manufactured by the narrow-channel three-dimensional impeller welding method has an outlet width of 10mm to 13mm for its blades 121, and the number of blades 121 is 11 to 20, specifically 15 blades 121. The blades 121 are characterized by slight twisting on the shaft and / or cover side, uniform thickness, locally thinned leading and trailing edges, and a longer leading edge extending into an arc segment, belonging to a narrow-channel three-dimensional impeller. Due to the narrow flow channel of the impeller and the twisted blades (121), integral EDM (Electrical Discharge Machining) is not feasible. EDM is inefficient and requires multiple steps, including electrode design, electrode machining, EDM of the entire impeller, and abrasive flow machining, making it take approximately three months to process a single impeller, resulting in a long processing cycle. Furthermore, EDM is expensive; machining a large-diameter, narrow-flow-channel ternary impeller can cost over 1 million RMB. Moreover, EDM equipment is not commonly used. When multiple narrow-flow-channel ternary impellers need to be machined simultaneously, waiting for sequential processing can lead to delays in delivery. Outsourcing further increases costs. Therefore, EDM machining of narrow-flow-channel ternary impellers has become a bottleneck restricting production.

[0027] In view of this, an embodiment of the first aspect of the present invention provides a welding method for a narrow-channel three-dimensional impeller, such as... Figure 1 As shown, the method includes:

[0028] Step 102: The blank is machined to form a wheel disc and wheel cover;

[0029] Step 104: Mill the blades on the wheel;

[0030] Step 106: Mill welding grooves on the wheel cover;

[0031] Step 108: Weld the impeller and the cover together by hand welding to form an impeller.

[0032] The narrow-channel three-dimensional impeller welding method provided in this embodiment of the invention processes the impeller by manual welding. Specifically, firstly, the blank is machined to form the impeller disc 120 and the impeller cover 110, and then... Figure 2 As shown, blades 121 are milled into the wheel 120, as follows: Figure 3As shown, a welding groove 111 is milled into the wheel cover 110. Then, the wheel disc 120 and the wheel cover 110 are welded together by hand to form an impeller. Compared with the impeller machining by electrical discharge machining in related technologies, this method simplifies the steps of electrode design and machining, which helps to shorten the machining cycle. At the same time, the machining cost is lower, which helps to reduce the manufacturing cost of narrow-channel three-dimensional impellers. Furthermore, when multiple narrow-channel three-dimensional impellers need to be welded, multiple operators can be assigned to manually weld them simultaneously. This avoids the problem of untimely delivery due to the limited number of electrical discharge machining equipment, and also avoids the problem of increased machining costs due to the need for outsourcing machining due to the limited number of electrical discharge machining equipment. It can meet the need to process multiple narrow-channel three-dimensional impellers simultaneously. In other words, the method of machining impellers by hand welding provided by the embodiments of the present invention has a short machining cycle, low machining cost, and wide applicability, making it suitable for widespread application.

[0033] Furthermore, such as Figure 4 As shown, the impeller 120 and the wheel cover 110 are welded together by the welding groove 111 to form an impeller. It is understood that the bottom 112 of the welding groove 111 needs to be penetrated to weld the blades 121, the solder, and the wheel cover 110 together, thus achieving an overall connection between the impeller 120 and the wheel cover 110. During the welding process, welding at the current position will cause deformation at adjacent welding positions. For example, if welding is performed sequentially from the beginning to the end of the welding groove 111, the bottom 112 of the welding groove 111 is divided into several welding positions, namely the first welding position, the second welding position, the third welding position, ..., the Nth welding position. When welding at the first welding position, the bottom 112 of the groove at the second welding position will deform. Especially for narrow-channel three-dimensional impellers with significant blade twisting, the deformation caused by welding often amplifies the twisting deformation of the blades 121. By performing welding manually, operators can directly and clearly observe the deformation at the second welding position. Therefore, they can reasonably adjust the welding conditions and parameters, such as the welding direction, welding time, and welding position, based on the deformation at the second welding position and the degree of twisting of the blade 121, to match the welding conditions and parameters with the deformed welding position and the degree of twisting of the blade 121, thereby ensuring a good welding effect. If a welding robot is used to weld the wheel cover 110 and the wheel disc 120 together through the welding groove 111, the welding parameters of the welding robot are preset in the system. Therefore, it is impossible to adjust the welding parameters according to the deformation caused during the welding process. At the same time, the diameter of the welding gun head of the welding robot is large, which cannot meet the welding needs of positions with small weld seams, thus limiting its use.

[0034] In other words, the embodiments provided by this invention weld the impeller 120 and the cover 110 together by manual welding. This allows for real-time adjustment of welding conditions and parameters based on deformation caused during welding, ensuring good welding results and improving impeller performance. Furthermore, the manual welding method uses smaller electrode and torch diameters, meeting the welding needs of smaller weld seams, expanding its application range, and making it suitable for widespread use.

[0035] In some possible implementations provided by the present invention, such as Figure 1 and Figure 5 As shown, the centerline of the welding groove 111 is positioned opposite to the centerline of the blade 121, meaning the profile of the welding groove 111 matches the profile of the blade 121. The length of the welding groove 111 is equal to the length of the blade 121. The side of the welding groove 111 away from the axis extends through the sidewall of the wheel cover 110. Furthermore, the width of the bottom 112 of the welding groove 111 is 0.4 to 0.6 mm wider than the width of the blade 121. This arrangement increases the contact area between the impeller, the solder, and the wheel cover 110 during the welding process of the blade 121 and the wheel cover 110, thereby improving the reliability of the welding between the impeller 120 and the wheel cover 110. Specifically, the width of the bottom 112 of the welding groove 111 is 0.4 mm, 0.5 mm, 0.6 mm, or other values ​​that meet the requirements, which are greater than the width of the blade 121.

[0036] Furthermore, the width of the bottom 112 of the welding groove 111 is smaller than the opening width. That is, the welding groove 111 is approximately a V-shaped groove, or it is a flared groove with a smaller bottom 112 width. This design facilitates welding by allowing the welding torch and welding rod to penetrate the bottom 112 of the welding groove 111 through the wider opening, simplifying the operation. It is understood that the groove wall of the welding groove 111 can be at least one of a plane, a bent surface, or a curved surface. The thickness of the bottom 112 of the welding groove 111 is 1.1mm to 1.3mm. This design facilitates rapid penetration of the bottom 112 during manual welding to connect the blade 121 to the solder and wheel cover 110, ensuring welding reliability while improving welding efficiency. Specifically, the thickness of the bottom 112 is 1.1mm, 1.2mm, 1.3mm, or other values ​​that meet the requirements.

[0037] By providing multiple first through holes along the length of the groove bottom 112, with the diameter of the first through holes being 0.8mm to 1.2mm larger than the width of the blade 121, operators can visually and clearly observe whether the centerline of the welding groove 111 and the center position of the blade 121 are consistent. Adjustments can be made if the centerlines of the welding groove 111 and the blade 121 are inconsistent, ensuring accurate alignment of the welding groove 111 and the blade 121. It is understood that the number of first through holes can be three, four, five, or other required numbers. Due to the significant twisting of the blade 121, multiple first through holes improve the accuracy of alignment between the welding groove 111 and the blade 121. To reduce processing costs, the number of first through holes can be set to three. Specifically, the diameter of the first through holes is 0.8mm, 0.1mm, 1.2mm larger than the width of the blade 121, or other required values.

[0038] In some possible implementations provided by the present invention, before step 108, the method further includes:

[0039] Step 107-1: Pre-assemble the wheel disc with milled blades and the wheel cover with milled welding grooves;

[0040] Step 107-2: Fix the pre-assembled wheel and wheel cover to the welding turntable; wherein, the welding turntable can drive the pre-assembled wheel and wheel cover to move as a whole, so as to adjust the welding position to the flat welding position.

[0041] In this embodiment, the specific steps for fixing the wheel disc 120 and wheel cover 110 to the welding turntable are described before the step of manually welding the wheel disc 120 and wheel cover 110 together. Specifically, the wheel disc 120 with milled blades 121 and the wheel cover 110 with milled welding grooves 111 are first pre-assembled. The wheel disc 120 with milled blades 121 is provided with a positioning part 122, and the wheel cover 110 with milled welding grooves 111 is provided with a limiting part 113. The wheel disc 120 and wheel cover 110 are pre-assembled by the appropriate pairing of the positioning part 122 and the limiting part 113. Specifically, the positioning part 122 and the limiting part 113 are positioning stops or other structures that meet the requirements. Positioning the wheel disk 120 and the wheel cover 110 through the positioning stops helps to improve the positioning accuracy and precision of the wheel disk 120 and the wheel cover 110, thereby improving the alignment accuracy of the welding groove 111 and the impeller and reducing the machining error of the impeller. It is understood that the positioning part 122 and the limiting part 113 can also be other structures that meet the requirements.

[0042] Specifically, the wheel 120 with milled blades 121 has a machining allowance before welding. Specifically, the outer diameter of the wheel 120 has a machining allowance of 20mm to 30mm, specifically 24mm; the inner diameter of the ring has a machining allowance of 8mm to 12mm, specifically 10mm; and the height has a machining allowance of 18mm to 22mm, specifically 20mm. The upper part of the shaft disc has a machining allowance of 3mm to 7mm, specifically 5mm; and the lower part has a machining allowance of 13mm to 17mm, specifically 15mm. The welding shrinkage of the blades 121 is 0.5mm to 0.9mm, specifically 0.7mm. The back of the shaft disc is flattened without leaving an angle to enhance rigidity and facilitate subsequent heat treatment loading. The positioning part 122 is a groove structure, set along the outer edge of the wheel 120, and located on the side of the wheel 120 facing the wheel cover 110.

[0043] The wheel cover 110, milled with welding grooves 111, has machining allowances before welding. Specifically, the outer diameter of the wheel cover 110 has a machining allowance of 22mm to 26mm, specifically 24mm; the outer diameter of the ring has a machining allowance of 8mm to 12mm, specifically 10mm; the height has a machining allowance of 11mm to 15mm, specifically 13mm; and the thickness of the wheel cover at the outlet is 8mm to 12mm, specifically 10mm, to ensure subsequent heat treatment and processing requirements. Three first through holes are drilled at appropriate positions along the inlet to outlet of the blade 121 at the bottom of the groove 112 as welding observation holes to facilitate observation during welding assembly. A protruding structure is provided on the wheel cover 110 at a position opposite to the groove structure in the wheel disc 120, serving as a limiting part 113.

[0044] Then, the pre-assembled wheel disc 120 and wheel cover 110 are fixed to the welding turntable. The welding turntable can move the pre-assembled wheel disc 120 and wheel cover 110 as a whole, thereby adjusting the welding position to a flat welding position. This setting helps improve welding quality and ensures a good welding effect, thus improving the working performance of the impeller. Specifically, the welding turntable can adjust the position of the wheel disc 120 and wheel cover 110 through a welding positioner to adjust the current welding position to a flat welding position. After the welding at the current position is completed, the position of the wheel disc 120 and wheel cover 110 can be adjusted again through the welding positioner to make the pre-welding position a flat welding position. Then, by operating in sequence, all welding positions of the welding grooves 111 can be welded in a flat welding position, which greatly improves welding quality and ensures a good welding effect. Specifically, for the welding of each welding groove 111, a symmetrical welding method can be adopted, using multiple layers and multiple passes, and each welding groove 111 is welded in a flat welding position, so that the welding rod and welding gun do not swing laterally, thereby improving the welding effect. Understandably, once a welded groove 111 is completed, it is necessary to strictly remove slag and visually inspect for defects in order to improve the welding quality.

[0045] Furthermore, since the welding groove 111 of the wheel cover 110 is equal in length to the wheel disc 120, meaning that the wheel cover 110 has welding grooves 111 along the entire length of the blade 121, the welding position differs from the slotted welding impeller welding method in related technologies. If the impeller is placed horizontally, there will be a vertical welding position at the opening of the wheel cover 110. Vertical welding is not conducive to ensuring welding quality and should be avoided as much as possible during operation. Therefore, in the embodiments of the present invention, the welding position is adjusted by the welding positioner of the welding turntable to ensure that the welding position is a flat welding position at all welding points, thereby improving welding quality and ensuring good welding effect, and improving the working performance of the impeller.

[0046] In some possible embodiments provided by the present invention, after step 107-2 and before step 108, the method further includes:

[0047] Step 107-3: A fixing ring is fitted around the outer periphery of the wheel and welded to the wheel; wherein, the fixing ring is provided with a vent hole, and the vent hole is connected to the flow channel between two adjacent blades.

[0048] Step 107-4: The wheel cover's opening ring is fitted onto the outer periphery of the fixing ring, and the fixing ring is welded to the wheel cover.

[0049] This embodiment describes a control scheme for preventing impeller deformation during the welding process. Specifically, as follows: Figure 5As shown, after the pre-assembled impeller 120 and impeller cover 110 are fixed to the welding turntable, and before welding the impeller 120 and impeller cover 110 together, a retaining ring 130 is welded to the outer periphery of the impeller 120 to reduce the deformation of the impeller 120, and a retaining ring 140 is welded to the opening of the impeller cover 110 to reduce the deformation of the impeller cover 110. Specifically, considering the structural characteristics of the welded impeller, the impeller cover 110 has a welding groove 111, which weakens the rigidity of the opening of the impeller cover 110. Therefore, auxiliary tooling for the welding process, including the retaining ring 140 and the retaining ring 130, is designed to provide rigid support and fixation for easily deformable parts, strictly controlling welding deformation. The specific process is as follows: after the impeller disk 120 and the wheel cover 110 are assembled and fixed to the welding turntable, a fixing ring 130 is first added to the outer circle of the wheel cover 110, and a fixing ring 140 is added to the opening ring of the wheel cover 110. The fixing ring 130 is first welded to the wheel cover 110, and then the fixing ring 140 is welded to the impeller disk 120.

[0050] Specifically, the structure of the fixing ring 130 is as follows: Figure 6 As shown, the retaining ring 130 is a circular ring structure with a thickness of 40mm to 60mm. The inner diameter of the retaining ring 130 matches the outer diameter of the impeller 120, and the machining accuracy of the inner wall surface of the retaining ring 130 at the contact point with the outer diameter of the impeller cover 110 needs to meet assembly tolerance requirements. Simultaneously, to meet welding requirements, the retaining ring 130 is provided with vent holes, which are connected to the flow channels between two adjacent blades 121. That is, based on the flow channel configuration of the impeller, the retaining ring 130 has vent holes along the circumferential direction at positions opposite to each flow channel. It is understood that the vent holes can be machined by drilling, and their diameter can be φ7mm, φ8mm, φ9mm, or other sizes that meet the requirements. It is understood that the radial length of the retaining ring 130 is 80mm to 150mm to enhance rigidity. It is understood that the retaining ring 130 is provided with a mounting hole 131. After the retaining ring 130 is fitted onto the outer circumference of the wheel 120, the retaining ring 130 and the wheel 120 are fastened together by passing a set screw through the mounting hole 131. Then, the two are connected together by welding to improve the reliability of the connection. It is understood that the mounting hole 131 can also be used to install other connecting parts to fasten the retaining ring 130 to the wheel 120. This invention does not specifically limit the connection.

[0051] The structure of the retaining ring 140 is as follows Figure 7As shown, the fixing ring 140 is a circular ring structure with a thickness of 40mm to 60mm. A positioning surface 141 is machined at the contact point between the fixing ring 140 and the inner diameter of the wheel cover 110's ring, used to support the ring portion of the wheel cover 110. The positioning surface 141 is used to position the fixing ring 140 against the wheel cover 110's ring. The dimensions of the positioning surface 141 are 15mm x 15mm, 20mm x 20mm, 25mm x 25mm, 20mm x 25mm, 15mm x 20mm, or other dimensions that meet the requirements. It can be understood that when the positioning surface 141 is 20mm x 20mm, it provides good support and fixation for the ring in both the axial and radial directions. The radial length of the fixing ring 140 is 100mm to 150mm to ensure the overall rigidity of the fixing ring 140.

[0052] In some possible implementations provided by the present invention, after step 108, the method further includes:

[0053] Step 110: Heat treat the welded impeller to eliminate welding stress; turn the heat-treated impeller to remove the retaining ring and retaining ring, as well as the machining allowance of the impeller disc and the impeller cover to form the finished impeller.

[0054] This embodiment describes the process of manufacturing a finished impeller from a welded impeller. First, the welded impeller is removed from the welding turntable and heat-treated to relieve welding stress. Then, the heat-treated impeller is machined to remove the machining allowances of the retaining ring 130, retaining ring 140, impeller disc 120, and impeller cover 110, ultimately forming the finished impeller.

[0055] Understandably, the quality of the weld can be inspected using X-rays, dye penetrant testing, or other methods after the impeller has been welded. If the weld is found to be substandard, it should be repaired promptly to ensure the quality of the impeller.

[0056] Furthermore, the turning process for the heat-treated impeller specifically includes:

[0057] The heat-treated impeller is rough-machined.

[0058] Weld inspection is performed on the impeller after rough machining;

[0059] The impellers that pass the inspection are then precision-machined to form the finished impeller.

[0060] In other words, the heat-treated impeller will be machined to remove the machining allowances of the retaining ring 130, retaining ring 140, impeller disc 120, and impeller cover 110, ultimately forming the finished impeller. The process is divided into two parts: rough turning and finish turning. Weld inspection is performed between rough turning and finish turning. This arrangement helps improve the accuracy of weld inspection and avoids situations where the weld surface is qualified but the internal weld is not. At the same time, if the weld inspection fails, it can be repaired in time. Then, the repaired impeller can be finished to produce the finished impeller, which helps reduce the defect rate, improve the pass rate of impeller processing, and reduce manufacturing costs.

[0061] In some possible implementations provided by the present invention, step 108 specifically includes:

[0062] Step 108-1: Seal the bottom using argon arc welding;

[0063] Step 108-2: Fill welding is performed using arc welding; wherein, multiple welding grooves are welded and sealed using a symmetrical welding method.

[0064] This embodiment describes a specific control scheme for welding the impeller 120 and the cover 110 together by manual welding to form an impeller. First, argon arc welding is used for the bottom sealing, which helps reduce weld defects, such as incomplete or missing welds. Then, electric arc welding is used for the filler welding, thereby welding the impeller 120 and the cover 110 together. This improves the reliability of the welding between the impeller 120 and the cover 110, ensures good weld quality, and enhances the impeller's working performance.

[0065] Furthermore, multiple welding grooves 111 are welded and sealed using a symmetrical welding method. For example, two welding grooves 111 located on the same diameter of the wheel cover 110 are welded and sealed one after the other. Alternatively, when welding any one welding groove 111 is completed, another welding groove 111 on the opposite side located on the same diameter, or a welding groove 111 on the opposite side adjacent to the same diameter, is welded. This avoids the problem of continuous welding of two adjacent welding grooves 111, which would cause the shrinkage allowance generated by welding to accumulate together and cause large errors. By welding multiple welding grooves 111 using a symmetrical welding method, it is possible to ensure uniform flow at the bottom 112 of the welding groove 111 and to distribute the shrinkage allowance generated by welding evenly to the adjacent welding grooves 111, thereby reducing errors, improving machining accuracy, and improving the working performance of the impeller.

[0066] Furthermore, the specific steps of argon arc welding for sealing the bottom include: preheating the impeller 120 and the impeller cover 110 to 150°C to 200°C, then using argon arc welding to weld the bottom 112 of the welding groove 111, while simultaneously purging the impeller 120 with argon gas at the position opposite to the welding position. That is, relative to the welding position, argon gas is purged from the back of the impeller, which provides a certain protective effect and helps improve the quality and reliability of the weld. Specifically, the argon arc welding is a self-fusion welding process, and the tungsten electrode diameter is 2.3mm to 2.8mm, the welding current is 150A to 160A, the argon purity is 99.80% to 99.99%, and the argon flow rate is 8L / min to 12L / min. Specifically, the tungsten electrode diameter is 2.3mm, 2.5mm, 2.8mm or other values ​​that meet the requirements; the welding current is 150A, 155A, 160A or other values ​​that meet the requirements; the argon purity is 99.80%, 99.90%, 99.99% or other values ​​that meet the requirements; and the argon flow rate during welding is 8L / min, 10L / min, 12L / min or other values ​​that meet the requirements.

[0067] Furthermore, the specific steps of using arc welding for filler welding include: using a welding electrode with a diameter of 3.2 mm to 4.0 mm and a welding current of 90 A to 160 A to fill the weld groove 111 with arc welding. The welding electrode is an FV520(B) stainless steel basic welding electrode. Specifically, when the diameter of the welding electrode is 3.2 mm, the welding current is 90 A to 120 A, and when the diameter of the welding electrode is 4.0 mm, the welding current is 120 A to 160 A. It can be understood that the diameter of the welding electrode can be other values ​​that meet the requirements, and the welding current can also be other values ​​that meet the requirements.

[0068] The narrow-channel three-dimensional impeller welding method provided by this invention differs from the slotted welding impeller welding method in related technologies. Since the welding groove 111 of the impeller cover 110 is equal in length to the impeller disc 120, meaning the entire length of the impeller cover 110 corresponding to the blade 121 is provided with welding grooves 111, the welding position differs from that of horizontally welded impellers. If the impeller is placed horizontally, there will be a vertical welding position at the opening of the impeller cover 110, which is detrimental to welding quality and should be avoided as much as possible during operation. Therefore, the embodiment of this invention uses a welding positioner on a welding turntable to adjust the welding position, ensuring that the welding position is a flat welding position at all welding points, thereby improving welding quality and ensuring good welding effect, and improving the working performance of the impeller. Simultaneously, to prevent welding deformation, a fixing ring 140 and a fixing ring 130 are added to control and protect against welding deformation. Furthermore, the fixing ring 140 and fixing ring 130 are simple to manufacture, easy to assemble and fix, greatly improving the overall quality of the impeller and contributing to improved impeller working performance. Furthermore, by manually welding the impeller disc 120 and the cover 110 together, the welding conditions and parameters can be adjusted in real time according to the deformation caused by welding to meet the needs of the current welding position, thereby ensuring good welding results and improving the impeller's working performance. At the same time, the smaller diameter of the welding rod and welding gun used in manual welding allows for the welding of smaller weld seams, expanding its application range and making it suitable for widespread use.

[0069] According to a second aspect of the present invention, a narrow-channel three-dimensional impeller is provided. This narrow-channel three-dimensional impeller is manufactured using the narrow-channel three-dimensional impeller welding processing method provided in any of the embodiments of the first aspect above. Therefore, it has all the technical effects of any of the embodiments of the first aspect above, which will not be described in detail here.

[0070] In this invention, the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0071] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0072] This invention is not limited to the above-described optional embodiments. Anyone can derive other various forms of products under the guidance of this invention. However, regardless of any changes made in their shape or structure, any technical solution that falls within the scope of the claims of this invention shall be protected by this invention.

Claims

1. A welding and processing method for a narrow-channel three-dimensional impeller, characterized in that, include: The blank is machined to form a wheel disc (120) and a wheel cover (110). Blades (121) are milled out on the wheel (120); A welding groove (111) is milled into the wheel cover (110); The impeller is formed by welding the disc (120) and the cover (110) together by hand welding. Before the step of welding the impeller (120) and the wheel cover (110) together by hand welding to form an impeller, the method further includes: The wheel disc (120) with the milled blades (121) and the wheel cover (110) with the milled welding grooves (111) are pre-assembled; The pre-assembled wheel disc (120) and wheel cover (110) are fixed to the welding turntable; The welding turntable can drive the pre-assembled wheel (120) and wheel cover (110) to move as a whole, so as to adjust the welding position to a flat welding position; The centerline of the welding groove (111) is arranged opposite to the centerline of the blade (121); The length of the welding groove (111) is equal to the length of the blade (121), and the width of the bottom (112) of the welding groove (111) is 0.4 to 0.6 mm larger than the width of the blade (121). The width of the bottom (112) of the welding groove (111) is smaller than the opening width. The thickness of the bottom (112) of the welding groove (111) is 1.1 mm to 1.3 mm; The groove bottom (112) is provided with a plurality of first through holes along the length direction, and the diameter of the first through holes is 0.8 to 1.2 mm larger than the width of the blade (121). After the step of fixing the pre-assembled wheel disc (120) and wheel cover (110) to the welding turntable, and before the step of welding the wheel disc (120) and wheel cover (110) together by manual welding to form an impeller, the method further includes: A fixing ring (130) is sleeved on the outer periphery of the wheel (120), and the fixing ring (130) is welded to the wheel (120). The opening of the wheel cover (110) is fitted around the outer periphery of the fixing ring (140), and the fixing ring (140) is welded to the wheel cover (110). The fixing ring (130) is provided with a vent hole, which is connected to the flow channel between two adjacent blades (121).

2. The narrow-channel three-dimensional impeller welding method according to claim 1, characterized in that, Also includes: The impeller is subjected to heat treatment after welding to eliminate welding stress; The heat-treated impeller is machined to remove the machining allowance of the retaining ring (130) and the retaining ring (140), as well as the machining allowance of the wheel disc (120) and the wheel cover (110) to form the finished impeller.

3. The narrow-channel three-dimensional impeller welding method according to any one of claims 1 to 2, wherein the step of welding the impeller disc (120) and the impeller cover (110) together by manual welding to form the impeller specifically includes: The bottom of the welding groove (111) is sealed by argon arc welding; The welding groove (111) is filled by electric arc welding; Among them, the bottom of multiple welding grooves (111) is welded by symmetrical welding.

4. The narrow-channel three-dimensional impeller welding method according to claim 3, characterized in that, The specific steps of the argon arc welding for sealing the bottom include: The wheel (120) and the wheel cover (110) are preheated to 150°C to 200°C; Argon arc welding is used to weld the bottom (112) of the welding groove (111), while argon gas is supplied to the wheel (120) at the position opposite to the welding position. The tungsten electrode diameter for the argon arc welding self-fusion welding is 2.3 mm to 2.8 mm, and the welding current is 150 A to 160 A; the purity of the argon gas is 99.80% to 99.99%, and the flow rate of the argon gas is 8 L / min to 12 L / min.

5. The narrow-channel three-dimensional impeller welding method according to claim 3, characterized in that, The specific steps of using arc welding for filler welding include: The weld groove (111) is filled by arc welding using welding rods with a diameter of 3.2 mm to 4.0 mm and a welding current of 90 A to 160 A.

6. The welding method for a narrow-channel three-dimensional impeller according to any one of claims 1 to 2, characterized in that, The wheel disk (120) with the milled blade (121) is provided with a positioning part (122), and the wheel cover (110) with the milled welding groove (111) is provided with a limiting part (113). The positioning part (122) and the limiting part (113) are used to pre-assemble the wheel (120) and the wheel cover (110) in a suitable manner.

7. A narrow-channel three-dimensional impeller, characterized in that, The narrow-channel three-dimensional impeller is manufactured by the narrow-channel three-dimensional impeller welding process described in claims 1 to 6.

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