Hook claw surfacing processing method and four-piece hook claw surfacing processing method

Abstract

The present invention provides a hook claw surfacing processing method and a four-joint hook claw surfacing processing method, comprising the following steps: step S1.1: processing a hook claw tooth portion to be welded hole on a hook claw part; step S1.2: placing the hook claw part in a heat treatment furnace for preheating, and then performing argon arc welding primer surfacing on the hook claw tooth portion to be welded hole; step S1.3: machining the argon arc welding surfacing layer on the hook claw tooth portion to be welded, retaining the surfacing layer of a preset thickness; step S1.4: preheating the hook claw part again, and continuing to perform surfacing welding on the hook claw tooth portion to be welded hole using oxyacetylene. The present invention uses argon arc welding combined with oxyacetylene welding and double-sided surfacing to perform hook claw small hole surfacing, effectively solving the problem that oxyacetylene surfacing easily causes carburization of the parent material and the problem that single-sided welding deep holes are inaccessible.

Description

Technical Field

[0001] The present invention relates to the technical field of hook claw processing, in particular to a hook claw surfacing processing method and a four-connection hook claw surfacing processing method, especially a control rod drive mechanism hook claw surfacing and processing method. Background Art

[0002] As the main equipment of the nuclear island, the control rod drive mechanism is a key servo mechanism of the control system and safety protection system of the nuclear power plant reactor, which directly affects the normal operation and safety reliability of the nuclear reactor. The hook is a key component for the normal operation of the control rod drive mechanism. Its performance quality determines whether the control rod drive mechanism can serve normally. The hook has a complex shape and a precise structure, and it is difficult to weld and process. Cobalt-based alloys have good high temperature resistance, corrosion resistance and wear resistance, and are ideal contact materials. They are often used in harsh working conditions, such as welding of the teeth and small holes of the hook of the control rod drive mechanism.

[0003] Due to the complex structure of the hook and the difficulty of cladding, the traditional method uses oxyacetylene welding with a special speed changer to clad the hook teeth and the hook holes. However, in the process of oxyacetylene cladding of cobalt-based alloys, since the oxyacetylene flame is a carburizing flame, the parent material 022Cr19Ni10N is prone to carburization, which increases the possibility of intergranular corrosion of the hook, which is not conducive to the long-term effective service of the control rod drive mechanism. In particular, the hook hole has a small aperture (aperture ) and deep (about 25mm), double-sided oxyacetylene cladding is required to fully fill the inner surface of the hook hole. Repeated double-sided cladding will further increase the possibility of carburization of the hook hole base material 022Cr19Ni10N.

[0004] Based on the above problems, the present invention adopts a method of combining argon arc welding and oxyacetylene welding to perform surfacing welding on the claw teeth and the claw small holes, and combines the machining process to form a set of hook manufacturing methods, avoiding carburization of the hook base material 022Cr19Ni10N, and solving the intergranular corrosion problem that may be caused by oxyacetylene surfacing. The surfacing layer is well formed, and after machining, the hook parts are qualified in liquid penetration test and Rockwell hardness test, meeting the product requirements of 39-47HRC. Summary of the invention

[0005] In view of the defects in the prior art, the object of the present invention is to provide a hook claw surfacing welding processing method and a four-connection hook claw surfacing welding processing method.

[0006] A control rod drive mechanism hook cladding processing method according to the present invention comprises the following steps:

[0007] Step S1.1: machining holes for welding of hook teeth on the hook parts;

[0008] Step S1.2: placing the hook claw part in a heat treatment furnace for preheating, and then performing argon arc welding to the welding holes of the hook claw teeth;

[0009] Step S1.3: machining the argon arc welding cladding layer on the to-be-welded hole of the claw tooth portion, and retaining the cladding layer of a preset thickness;

[0010] Step S1.4: preheat the hook claw part again, and continue to perform surfacing welding on the holes to be welded on the teeth of the hook claw using oxyacetylene.

[0011] Preferably, in step S1.1, the surface to be welded is wiped clean with alcohol.

[0012] Preferably, in step S1.2, the base material of the hook part is austenitic stainless steel, and the preheating temperature is above 350°C;

[0013] In the step S1.2, the number of surfacing layers is 1 to 2, the hole depth of the surfacing area is ≥37 mm, and the surfacing is performed along the circumferential surface of the inner hole.

[0014] Preferably, in step S1.3, the thickness of the weld overlay layer is retained to be 2 mm.

[0015] Preferably, in step S1.4, the preheating temperature is above 350°C;

[0016] In the step S1.4, the number of surfacing layers is 3 to 6, the hole depth of the surfacing area is ≥37 mm, and the surfacing is performed along the circumferential surface of the inner hole.

[0017] The present invention also provides a four-joint hook claw cladding processing method, which processes the hook claw parts processed by the above-mentioned control rod drive mechanism hook claw cladding processing method, comprising the following steps:

[0018] Step S2.1: machining a small hole of the hook to be welded on one side of the four-joint hook machine, and machining the teeth of the hook after surfacing welding;

[0019] Step S2.2: placing the hook part into a heat treatment furnace for preheating, and then performing argon arc welding to base weld the small hole of the hook on one side;

[0020] Step S2.3: machining a argon arc welding cladding layer on the small hole of the hook claw to be welded on one side, and retaining a cladding layer of a preset thickness;

[0021] Step S2.4: preheating the hook part again, and then using oxyacetylene to continue surfacing welding on one side of the hook hole to be welded;

[0022] Step S2.5: machining the other side of the four-joint hook part to be welded with a small hole;

[0023] Step S2.6: placing the hook part in a heat treatment furnace for preheating, and then performing argon arc welding to base weld the small hole of the hook on the other side to be welded;

[0024] Step S2.7: machining the argon arc welding cladding layer on the small hole of the hook claw to be welded on the other side, and retaining the cladding layer of a preset thickness;

[0025] Step S2.8: preheating the hook part again, and continuing to perform surfacing welding on the other side of the hook hole to be welded using oxyacetylene;

[0026] Step S2.9: Process the tooth shape of the four-piece hook part and cut it into four parts by wire cutting.

[0027] Preferably, in step 2.1, the small hole of the hook to be welded is wiped clean with alcohol;

[0028] In the step 2.5, the small hole of the hook to be welded is wiped clean with alcohol.

[0029] Preferably, in step S2.2, the preheating temperature is above 350°C; in step S2.2, the number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥15mm, and the surfacing is performed along the circumferential surface of the inner hole;

[0030] In the step 2.6, the preheating temperature is above 350°C; in the step 2.6, the number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥15mm, and the surfacing is performed along the circumferential surface of the inner hole.

[0031] Preferably, in step S2.3, the thickness of the cladding layer is retained to be 2 mm;

[0032] In step 2.7, the thickness of the weld overlay layer is kept at 2 mm.

[0033] Preferably, in step 2.4, the preheating temperature is above 350°C; in step 2.4, the number of surfacing layers is 2 to 4, the hole depth of the surfacing area is ≥15mm, and the surfacing is performed along the circumferential surface of the inner hole;

[0034] In the step 2.8, the preheating temperature is above 350° C.; in the step 2.8, the number of surfacing layers is 2 to 4, the hole depth of the surfacing area is ≥15 mm, and the surfacing is performed along the circumferential surface of the inner hole.

[0035] Preferably, the hook holes to be welded on both sides are cylindrical holes to be welded and conical holes to be welded respectively.

[0036] Preferably, the four-piece hook claw part is processed by mandrel clamping and cross processing.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. The present invention adopts argon arc welding to make the base cladding isolation layer, thus avoiding carburization of the hook claw base material and solving the intergranular corrosion problem that may be caused by oxyacetylene cladding.

[0039] 2. The present invention adopts argon arc welding + oxyacetylene welding and double-sided surfacing to perform hook claw small hole surfacing, which effectively solves the problem that single-sided welding deep holes are inaccessible.

[0040] 3. The present invention adopts two types of small holes to be welded, cylindrical and conical. The small holes to be welded have good single-sided accessibility, which effectively solves the problem of different requirements for the penetration depth of the hook holes.

[0041] 4. The present invention adopts integral surfacing and processing of four-piece hook parts, which improves the efficiency of hook manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0043] Figure 1 This is a schematic diagram of processing the holes to be welded on the claw teeth;

[0044] Figure 2 It is a schematic diagram of the processing of the hook claw teeth after welding and the small hole of the hook claw to be welded on one side;

[0045] Figure 3 This is a schematic diagram of processing the small hole of the hook claw to be welded on the other side;

[0046] Figure 4 This is a schematic diagram of the wire cutting of the four-jointed hook claw;

[0047] Figure 5 This is a schematic diagram of a single hook product;

[0048] Figure 6 A flowchart of the steps of the hook claw cladding processing method;

[0049] Figure 7 It is a schematic diagram of the thickness of the surfacing layer of the hook eyelet;

[0050] Figure 8 for Figure 5 Front view of the middle hook;

[0051] Fig. 9 for Figure 5 Rear view of the middle hook;

[0052] Fig.10 for Figure 5 Cross-section of the middle hook;

[0053] Fig.11 for Fig.10 A partial enlarged schematic diagram of the middle I part;

[0054] Fig.12 for Fig.10 Schematic diagram of the cross section along line AA. DETAILED DESCRIPTION

[0055] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0056] Embodiment 1:

[0057] like Figures 1 to 6 As shown, this embodiment provides a hook surfacing processing method for processing the hook teeth and hook holes of the Hualong One hook part. The base material grade of the hook part is 022Cr19Ni10N, and the welding material grade is ERCoCr-A.

[0058] The specific steps include:

[0059] Step S1.1: Process the welding holes of the claw teeth on the claw part; wipe and clean the welding surface with alcohol.

[0060] Step S1.2: Place the hook claw part in a heat treatment furnace for preheating, and then perform argon arc welding on the holes to be welded on the hook claw teeth; the preheating temperature is above 350°C; the number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥37mm, and the surfacing is performed along the circumferential surface of the inner hole.

[0061] Step S1.3: machining the argon arc welding cladding layer on the to-be-welded hole of the claw tooth portion, and retaining the cladding layer of a preset thickness; the thickness of the retained cladding layer is 2 mm.

[0062] Step S1.4: preheat the hook claw part again, and continue to perform surfacing welding on the holes to be welded on the hook claw teeth with oxyacetylene; the preheating temperature is above 350°C; the number of surfacing layers is 3 to 6 layers, the hole depth of the surfacing area is ≥37mm, and surfacing welding is performed along the circumferential surface of the inner hole.

[0063] This embodiment also provides a four-joint hook claw surfacing welding processing method, which processes the hook claw part processed by the above hook claw surfacing welding processing method, including the following steps:

[0064] Step S2.1: machining a small hole of the hook to be welded on one side of the four-joint hook machine, and machining the teeth of the hook after surfacing welding; wiping and cleaning the small hole of the hook to be welded with alcohol;

[0065] Step S2.2: placing the hook part in a heat treatment furnace for preheating, and then performing argon arc welding to base weld the small hole of the hook to be welded on one side; the preheating temperature is above 350°C; the number of cladding layers is 1 to 2 layers, the hole depth of the cladding area is ≥15mm, and cladding is performed along the circumference of the inner hole;

[0066] Step S2.3: machining the argon arc welding cladding layer on the small hole of the hook claw to be welded on one side, and retaining the cladding layer with a preset thickness; the thickness of the retained cladding layer is 2 mm;

[0067] Step S2.4: preheat the hook part again, and then continue to perform surfacing welding on the small hole of the hook to be welded on one side with oxyacetylene; the preheating temperature is above 350°C; the number of surfacing layers is 2 to 4 layers, the hole depth of the surfacing area is ≥15mm, and the surfacing is performed along the circumference of the inner hole;

[0068] Step S2.5: machining a small hole for the hook to be welded on the other side of the four-joint hook part; wiping and cleaning the small hole for the hook to be welded with alcohol;

[0069] Step S2.6: Place the hook part in a heat treatment furnace for preheating, and then perform argon arc welding on the other side of the hook hole to be welded; the preheating temperature is above 350°C; the number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥15mm, and the surfacing is performed along the circumference of the inner hole;

[0070] Step S2.7: machining the argon arc welding cladding layer on the small hole of the hook claw to be welded on the other side, and retaining the cladding layer with a preset thickness; the thickness of the retained cladding layer is 2 mm;

[0071] Step S2.8: preheat the hook part again, and continue to perform surfacing welding on the other side of the hook hole to be welded using oxyacetylene; the preheating temperature is above 350°C; the number of surfacing layers is 2 to 4 layers, the hole depth of the surfacing area is ≥15mm, and the surfacing is performed along the circumference of the inner hole;

[0072] Step S2.9: Process the tooth shape of the four-piece hook part and cut it into four parts by wire cutting.

[0073] The hook holes on one side and the hook holes on the other side can be cylindrical and conical, which not only ensures good accessibility of the cladding, but also meets the problem that the hook holes have different requirements for the thickness of the cladding layer, such as Figure 7 The four-piece hook part is cross-shaped and is processed by mandrel clamping and cross processing.

[0074] The present invention adopts the welding method of argon arc welding + oxyacetylene welding for hook claw cladding for the first time, the cladding layer is well formed, and after machining, the hook claw parts pass the liquid penetration test and the Rockwell hardness test, meeting the product technical requirements.

[0075] The present invention adopts the argon arc welding base cladding method for the first time, thereby avoiding carburization of the hook claw base material 022Cr19Ni10N and solving the intergranular corrosion problem that may be caused by oxyacetylene cladding.

[0076] The present invention adopts argon arc welding + oxyacetylene welding and double-sided cladding for the first time, effectively solving the problem of deep hole cladding being inaccessible and reducing welding deformation.

[0077] The present invention adopts two types of small holes to be welded, cylindrical and conical, for the first time. The small holes to be welded have good single-sided accessibility and high practicality for surfacing welding, and effectively solve the problem that the hook small holes have different requirements for penetration depth.

[0078] The present invention adopts the method of mandrel clamping and cross processing for the first time for processing four-piece hook claw parts, thereby ensuring the dimensional accuracy of the hook claw parts.

[0079] The present invention adopts the overall surfacing and processing of the four-piece hook claw parts for the first time. After the surfacing is completed, wire cutting and machining are adopted to finally process them into four hook claw parts, thereby improving the efficiency of hook claw manufacturing.

[0080] Embodiment 2:

[0081] Those skilled in the art may understand this embodiment as a more specific description of Embodiment 1.

[0082] The present embodiment provides a method for surfacing and processing the hook of a control rod drive mechanism, which is used to process the hook teeth and hook holes of the Hualong One hook part. The base material grade of the hook part is 022Cr19Ni10N, and the welding material grade is ERCoCr-A.

[0083] The specific steps include:

[0084] The first step is to process the holes to be welded on the claw teeth. Figure 1 As shown, wipe the surface to be welded with alcohol;

[0085] The second step is to put the hook claw parts into a heat treatment furnace, preheat the temperature to above 350°C, and then perform argon arc welding on the holes to be welded on the hook claw teeth. The number of surfacing layers is 1 to 2 layers, the hole depth in the surfacing area is ≥37mm, and surfacing is performed along the circumference of the inner hole.

[0086] The third step is to machine the argon arc welding cladding layer, and keep the cladding layer thickness about 2mm;

[0087] Step 4: Preheat the temperature to above 350°C, continue surfacing welding with oxyacetylene, the number of surfacing welding layers is 3 to 6, the hole depth of the surfacing welding area is ≥37mm, and surfacing welding is performed along the circumference of the inner hole;

[0088] The fifth step is to machine one side of the four-piece hook to be welded, and the small hole and the teeth of the hook to be welded, such as Figure 2 As shown, wipe the small holes to be welded with alcohol;

[0089] Step 6: Place the hook parts in a heat treatment furnace, preheat the temperature to above 350°C, and then perform argon arc welding on the small hole of the hook to be welded on one side. The number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥15mm, and surfacing is performed along the circumference of the inner hole.

[0090] Step 7: Machining the argon arc welding cladding layer, keeping the cladding layer thickness of about 2mm;

[0091] Step 8: Preheat the temperature to above 350°C, continue surfacing welding with oxyacetylene, the number of surfacing welding layers is 2 to 4, the hole depth of the surfacing welding area is ≥15mm, and surfacing welding is performed along the circumference of the inner hole;

[0092] Step 9: For the four-piece hook parts, machine the small holes for the hooks to be welded on the other side. Figure 3 As shown, wipe the small holes to be welded with alcohol;

[0093] Step 10: Preheat the temperature to above 350°C, perform argon arc welding to the other side of the hook hole to be welded, the number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥15mm, and surfacing is performed along the circumference of the inner hole;

[0094] Step 11: machining the argon arc welding cladding layer, and retaining the cladding layer thickness of about 2 mm;

[0095] Step 12: Preheat the temperature to above 350°C, continue surfacing with oxyacetylene, the number of surfacing layers is 2 to 4, the hole depth of the surfacing area is ≥15mm, and surfacing is performed along the circumference of the inner hole;

[0096] Step 13: Process the tooth shape of the four-jointed hook parts and cut them into 4 parts by wire cutting. The wire cutting diagram is as follows: Figure 4 As shown;

[0097] Step 14: Final machining to the hook product size, such as Figure 5 shown.

[0098] In the second, sixth and tenth steps, the hook parts should be fully preheated in the heat treatment furnace, and can be placed in the heat treatment furnace at a temperature of 350-425℃, and kept warm for ≥1h; the argon arc welding primer should be surfacing with small parameters as much as possible to reduce the dilution of the parent material to the weld. In the actual operation process, a variable speed machine can be used to achieve uniform speed surfacing in the flat welding position to achieve uniform thickness of the surfacing layer.

[0099] In the fifth step, since there are two types of small holes in the product hook claw and the thickness requirements of the cladding layer are different, the small holes to be welded are opened into two types, one is cylindrical and the other is conical, with 4 holes each. Figure 2 As shown; use a clamping and pushing method to clamp the mandrel and install the parts on the mandrel, such as Figure 2 Processing shown.

[0100] In the ninth step, the small hole to be welded on the other side is machined, the mandrel is clamped by a clamp-and-top method, the part is mounted on the mandrel, and the small hole shape on the reverse side of the cladding layer is machined, such as Figure 3 Processing shown.

[0101] In the thirteenth and fourteenth steps, the part needs to be cut into four pieces by wire cutting, and then processed to the final size of the hook by CNC machine tools.

[0102] Embodiment 3:

[0103] Those skilled in the art may understand this embodiment as a more specific description of Embodiment 1.

[0104] This embodiment provides a method for surfacing and processing the hook of a control rod drive mechanism, which is used to process the hook teeth and hook holes of the Hualong One hook parts. The base material grade of the welded part is 022Cr19Ni10N, and the welding material grade is ERCoCr-A. The manufacturing process of the hook is as follows:

[0105] The first step is to process the holes to be welded on the claw teeth. Figure 1 As shown, wipe the surface to be welded with alcohol;

[0106] The second step is to put the hook claw parts into a heat treatment furnace, preheat the temperature to above 350°C, and then perform argon arc welding on the holes to be welded on the hook claw teeth. The number of surfacing layers is 1 to 2 layers, the hole depth in the surfacing area is ≥37mm, and surfacing is performed along the circumference of the inner hole.

[0107] The third step is to machine the argon arc welding cladding layer, and keep the cladding layer thickness about 2mm;

[0108] Step 4: Preheat the temperature to above 350°C, continue surfacing welding with oxyacetylene, the number of surfacing welding layers is 3 to 6, the hole depth of the surfacing welding area is ≥37mm, and surfacing welding is performed along the circumference of the inner hole;

[0109] The fifth step is to machine one side of the four-piece hook to be welded, and the small hole and the teeth of the hook to be welded, such as Figure 2 As shown, wipe the small holes to be welded with alcohol;

[0110] Step 6: Place the hook parts in a heat treatment furnace, preheat the temperature to above 350°C, and then perform argon arc welding on the small hole of the hook to be welded on one side. The number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥15mm, and surfacing is performed along the circumference of the inner hole.

[0111] Step 7: Machining the argon arc welding cladding layer, keeping the cladding layer thickness of about 2mm;

[0112] Step 8: Preheat the temperature to above 350°C, continue surfacing welding with oxyacetylene, the number of surfacing welding layers is 2 to 4, the hole depth of the surfacing welding area is ≥15mm, and surfacing welding is performed along the circumference of the inner hole;

[0113] Step 9: For the four-piece hook parts, machine the small holes for the hooks to be welded on the other side. Figure 3 As shown, wipe the small holes to be welded with alcohol;

[0114] Step 10: Preheat the temperature to above 350°C, perform argon arc welding to the other side of the hook hole to be welded, the number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥15mm, and surfacing is performed along the circumference of the inner hole;

[0115] Step 11: machining the argon arc welding cladding layer, and retaining the cladding layer thickness of about 2 mm;

[0116] Step 12: Preheat the temperature to above 350°C, continue surfacing with oxyacetylene, the number of surfacing layers is 2 to 4, the hole depth of the surfacing area is ≥15mm, and surfacing is performed along the circumference of the inner hole;

[0117] Step 13: Process the tooth shape of the four-jointed hook parts and cut them into 4 parts by wire cutting. The wire cutting diagram is as follows: Figure 4 As shown;

[0118] Step 14: Final machining to the hook product size, such as Figure 5 shown.

[0119] In the second, sixth and tenth steps, the claw parts should be fully preheated in the heat treatment furnace, and can be placed in a heat treatment furnace with a furnace temperature of 350-425℃ for ≥1h. The minimum parameters for argon arc welding primer are: welding current 30-60A, welding voltage 3-10V, welding speed 12-17cm / min, welding material ERCoCr-A, In order to reduce the dilution of the parent material to the weld. In the actual operation process, a variable speed machine can be used to achieve uniform speed surfacing in the flat welding position to achieve the purpose of uniform thickness of the surfacing layer.

[0120] In the fourth, eighth and twelfth steps, the hook parts should be fully preheated in the heat treatment furnace. They can be placed in a heat treatment furnace with a temperature of 350-425°C and kept warm for ≥1h. Oxyacetylene welding parameters: carburizing flame (the length of the middle flame is about 2-2.5 times that of the inner flame), oxygen 0.3-0.7MPa, acetylene 0.03-0.07MPa, welding material ERCoCr-A, In actual operation, a speed changer can be used to achieve uniform speed surfacing in the flat welding position to achieve uniform thickness of the surfacing layer.

[0121] In the fifth step, since there are two types of small holes in the product hook claw and the thickness requirements of the cladding layer are different, the small holes to be welded are opened into two types, one is cylindrical and the other is conical, with 4 holes each. Figure 2 As shown; use a clamping and pushing method to clamp the mandrel, install the parts on the mandrel, and press Figure 2 Process the cross to ensure the width. Due to the large machining allowance, a small cutting depth and fast tool movement method is used to control part deformation during the machining process. The four hooks can very conveniently control the size from the center of the small hole to the center of rotation of the workpiece on the same blank, that is, ensure the 36.5 size of the bottom hole before welding. The processing method of the tapered hole is to first use a center drill on the CNC machining center, then drill a through hole, and then expand the hole with a milling cutter, use computer-aided programming or macro program generation to roughly mill the tapered hole, and finally use a customized forming milling cutter for fine machining to ensure the size and surface roughness of the hole;

[0122] In the ninth step, the outer circle of the four-piece workpiece and the stopper that matches the core rod are turned out (to remove the oxide layer), and the cross is milled out on the machining center (to remove the oxide layer), and the reverse side of the welded small hole (the small hole to be welded) is processed in the same way as the small hole processing in the fifth step. Figure 3 shown.

[0123] In the seventh and eleventh steps, the outer circle of the four-piece workpiece and the stopper that matches the core rod are turned out (to remove the oxide layer), and the cross shape is milled out on the machining center (to remove the oxide layer). The small holes for surfacing are processed in the same way as the small hole processing in the fifth step, and the thickness of the surfacing layer is kept not less than 2mm.

[0124] In the thirteenth step, the outer circle of the 4-piece workpiece and the stopper that matches the mandrel are turned out (to remove the oxide layer), the claw thickness 25±0.05 and the back groove blank are processed on the machining center, and the hardness of the surfacing layer is tested after processing the 2-Ф9 through hole; the 2-Ф9 through hole is expanded to Ensure the center distance is 36.5±0.025 and 38.095±0.025; use tooling to Through-hole positioning, machining the tooth shape after surfacing by lathe; using wire cutting to cut the parts into 4 pieces, and then using a grinder to symmetrically grind the two planes to 24.82±0.02; honing Through hole to 2-Ф9.493±0.007, ensure the surface roughness of small hole is 1.6; Position with 2-Ф9.493±0.007 small hole, finish R25 back groove, such as Figures 8 to 12 shown.

[0125] In the fourteenth step, three-dimensional modeling is performed, and a ball end mill is used to simulate the processing of the R3 chamfer on the tooth surface side through computer-aided programming. After the simulation is correct in the computer, a program is generated and transmitted to the machine tool to process the R3 chamfer on the tooth surface side.

[0126] The present invention adopts argon arc welding combined with oxyacetylene welding and double-sided cladding to perform hook claw small hole cladding, which effectively solves the problem that oxyacetylene cladding easily causes carburization of the base material and the problem that single-sided welding deep holes are inaccessible.

[0127] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A hook surfacing method, characterized in that: The steps include: Step S1.1: machining holes for welding of hook teeth on the hook parts; Step S1.2: placing the hook claw part in a heat treatment furnace for preheating, and then performing argon arc welding to the welding holes of the hook claw teeth; Step S1.3: machining the argon arc welding cladding layer on the to-be-welded hole of the claw tooth portion, and retaining the cladding layer of a preset thickness; Step S1.4: preheating the hook claw part again, and continuing to perform surfacing welding on the holes to be welded on the teeth of the hook claw using oxyacetylene; In the step S1.2, the base material of the hook part is austenitic stainless steel, and the preheating temperature is above 350°C; In the step S1.2, the number of surfacing layers is 1 to 2, the hole depth of the surfacing area is ≥ 37 mm, and the surfacing is performed along the circumferential surface of the inner hole; In step S1.4, the preheating temperature is above 350°C; In the step S1.4, the number of surfacing layers is 3 to 6, the hole depth of the surfacing area is ≥37 mm, and the surfacing is performed along the circumferential surface of the inner hole.

2. The hook claw surfacing method according to claim 1, characterized in that: In the step S1.1, the surface to be welded is wiped clean with alcohol.

3. The hook claw surfacing method according to claim 1, characterized in that: In the step S1.3, the thickness of the weld overlay layer is kept at 2 mm.

4. A method for surfacing welding of four-joint hook claws, characterized in that: Processing the hook claw part processed by the hook claw surfacing processing method according to any one of claims 1 to 3 comprises the following steps: Step S2.1: machining a small hole of the hook to be welded on one side of the four-joint hook machine, and machining the teeth of the hook after surfacing welding; Step S2.2: placing the hook part into a heat treatment furnace for preheating, and then performing argon arc welding to base weld the small hole of the hook on one side; Step S2.3: machining a argon arc welding cladding layer on the small hole of the hook claw to be welded on one side, and retaining a cladding layer of a preset thickness; Step S2.4: preheating the hook part again, and then using oxyacetylene to continue surfacing welding on one side of the hook hole to be welded; Step S2.5: machining the other side of the four-joint hook part to be welded with a small hole; Step S2.6: placing the hook part in a heat treatment furnace for preheating, and then performing argon arc welding to base weld the small hole of the hook on the other side to be welded; Step S2.7: machining the argon arc welding cladding layer on the small hole of the hook claw to be welded on the other side, and retaining the cladding layer of a preset thickness; Step S2.8: preheating the hook part again, and continuing to perform surfacing welding on the other side of the hook hole to be welded using oxyacetylene; Step S2.9: machining the tooth shape of the four-jointed hook part and cutting it into four parts by wire cutting; In the step S2.2, the preheating temperature is above 350°C; in the step S2.2, the number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥15mm, and the surfacing is performed along the circumferential surface of the inner hole; In the step 2.6, the preheating temperature is above 350°C; in the step 2.6, the number of surfacing layers is 1 to 2 layers, the hole depth of the surfacing area is ≥15mm, and the surfacing is performed along the circumferential surface of the inner hole; In the step 2.4, the preheating temperature is above 350°C; in the step 2.4, the number of surfacing layers is 2 to 4, the hole depth of the surfacing area is ≥15mm, and the surfacing is performed along the circumferential surface of the inner hole; In the step 2.8, the preheating temperature is above 350° C.; in the step 2.8, the number of surfacing layers is 2 to 4, the hole depth of the surfacing area is ≥15 mm, and the surfacing is performed along the circumferential surface of the inner hole.

5. The method for surfacing welding of four-joint hook claws according to claim 4, characterized in that: In the step 2.1, the small hole of the hook to be welded is wiped clean with alcohol; In the step 2.5, the small hole of the hook to be welded is wiped clean with alcohol.

6. The method for surfacing welding of four-joint hook claws according to claim 4, characterized in that: In step S2.3, the thickness of the cladding layer is kept at 2 mm; In step 2.7, the thickness of the weld overlay layer is kept at 2 mm.

7. The method for surfacing welding of four-joint hooks according to claim 4, characterized in that: The small holes for the hooks to be welded on both sides are respectively a cylindrical small hole for welding and a conical small hole for welding.

8. The method for surfacing welding of four-joint hooks according to claim 4, characterized in that: The processing of four-piece hook claw parts adopts the method of mandrel clamping and cross processing.

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