Forge welding type cable saddle groove forming process

Abstract

The invention relates to the technical field of application of forging and welding technologies in manufacturing and forming of suspension bridge cable saddles, and particularly discloses a forming process of a forge welding type cable saddle groove. The main technological process comprises the steps that firstly, an alloy material is forged into a rectangular blank through a forging technology, secondly, the forged rectangular blank is machined into a radian structure of a segmented groove bottom plate, thirdly, the segmented groove bottom plate is welded into a whole, and thirdly, the groove bottom plate and a side wall plate are welded to obtain the cable saddle groove. In the prior art, a cast cable saddle groove is heavier and heavier and is inconvenient to process, transport and hoist; and the strength of the cable saddle groove is not matched with that of a main cable steel wire.

Description

Technical Field

[0001] The invention relates to the technical field of application of forging and welding technology in manufacturing and forming of suspension bridge saddles, in particular to a forming process of a forged and welded saddle groove. Background Art

[0002] A suspension bridge is a bridge that uses cables as the main load-bearing components. Its characteristic is that the cables suspended from high towers and anchored on both banks (or both ends of the bridge) are used as the main load-bearing components of the superstructure. The construction of a suspension bridge allows it to use less material to span longer distances, which makes the suspension bridge one of the preferred forms of long-span bridge design.

[0003] The saddle is an important load-bearing component of the suspension bridge, and the saddle groove is the main component of the saddle and also the core component. Castings have a wide range of adaptability, are not limited by the size, thickness and complexity of the castings, and have flexible production methods. Therefore, the saddle is usually processed by casting technology, and its molding process is divided into two types: one is to cast the saddle groove and the saddle as one, and the other is to cast the saddle groove separately and then weld it with the saddle. Therefore, no matter which method is used, the saddle groove must be formed by casting technology. The function of the saddle groove is to support and transfer the load to the suspension cable, and it is an important load-bearing component. Therefore, the larger the span of the suspension bridge, the higher the strength requirement of the saddle groove, and the greater the overall weight of the saddle groove, which leads to the overall weight of the saddle becoming heavier and heavier. For example, in a long-span suspension bridge, the traditional cast saddle is used, and the total weight of each set of loose saddles reaches 200 tons, and the maximum lifting weight of a single piece reaches 150 tons; and as the span of the bridge increases, oversized saddle structures are common, making the overall weight of the saddle heavier and heavier. The change in the weight of the saddle makes the entire process of the saddle, including casting, transportation, hoisting, installation, etc., increasingly difficult and complicated. Designing the saddle groove to be lightweight while meeting the strength requirement is one of the important topics in future suspension bridges.

[0004] And with the increase of span, the tensile strength grade of the main cable steel wire has increased from 1670MPa to more than 2000MPa, while the steel casting has the characteristics of uneven organization, coarse internal grains and non-dense organization, which leads to its low mechanical properties. With the increase of the strength of the main cable, the pressure on the saddle groove per unit cross section also increases accordingly, and the contact stress at the bottom of the saddle groove increases. Through the sliding test of cast steel saddle and high-strength steel wire strands, it was found that after the strands slipped, very obvious and dense main cable wire tensile indentations were formed on the side walls and bottom of the saddle groove, and the indentation depth was mostly between 0.5 and 1mm, and even exceeded 1mm in some cases. Therefore, the molding quality and mechanical properties of the super-large casting saddle groove face practical challenges, and even the strength of its material is no longer compatible with the high-strength main cable steel wire.

[0005] Therefore, exploring a lightweight, high-strength saddle groove manufacturing process is one of the important issues that urgently needs to be solved in the industry. Summary of the invention

[0006] The object of the present invention is to provide a forming process for a forged-welded saddle trough, so as to solve the above-mentioned technical problems that as the span of the suspension bridge increases, the weight of the cast saddle trough in the prior art becomes heavier and heavier, which is inconvenient to process, transport and hoist; and the strength of the saddle trough does not match the main cable steel wire.

[0007] In order to solve the above problems, the technical solution adopted by the present invention is as follows: a forming process of a forged-welded saddle groove, wherein the saddle groove comprises a forged groove bottom plate and a side wall plate, and the forged-welded forming process comprises the following steps:

[0008] Step 1: Forging: According to the designed structural dimensions of the bottom plate of the saddle trough, the bottom plate of the saddle trough is divided into 2-3 segmented bottom plates, and an alloy block made of 30CrMo alloy structural steel is selected for forging, and the alloy block is forged into a rectangular blank larger than the size of the segmented bottom plate;

[0009] Step 2: Rough machining: Rough machining the blank according to the arc shape of the segmented groove bottom plate of the saddle groove, so that the blank forms an arc structure consistent with the segmented groove bottom plate;

[0010] Step 3: Groove bottom plate welding: fix and connect the three rough-machined segmented groove bottom plates into a rough-machined groove bottom plate;

[0011] Step 4: Side wall plate welding: weld the side wall plate on the rough-machined groove bottom plate to form a rough-machined saddle groove;

[0012] Step 5: Finishing: The rough-machined saddle groove is machined to a saddle groove that is consistent with the designed size.

[0013] The beneficial effects of this embodiment are:

[0014] 1. The bottom plate of the saddle trough directly bears the pressure transmitted by the cable, and the bottom plate of the saddle trough has the highest requirements for strength and toughness. Traditional saddle troughs are generally cast. In order for the saddle trough to be able to bear the pressure transmitted by the cable, the cast saddle trough in the prior art usually increases the material consumption to ensure the reliability of strength, making the overall volume and weight of the saddle trough larger and larger, making it more difficult to process, transport and hoist. In the present application, the saddle trough is forged, and forging improves the strength of the material. While reducing the material consumption, the reliability of strength can also be ensured, so that the overall volume and weight of the saddle trough of the present application are reduced, making it simpler to process, transport and hoist.

[0015] 2. The saddle groove is in direct contact with the cable. The bottom plate of the saddle groove directly bears the pressure transmitted by the cable. The bottom plate of the saddle groove has the highest requirements for strength and toughness. Traditional saddle grooves are generally cast. In order for the saddle groove to bear the pressure transmitted by the cable, the material consumption is usually increased to ensure the reliability of strength. However, steel castings have the characteristics of uneven organization and coarse internal grains. The first layer of liquid metal that contacts the mold wall after the liquid metal is injected into the mold has the fastest temperature drop, so it quickly solidifies into finer grains. As the distance from the mold wall increases, the influence of the mold wall gradually weakens, and the crystals grow into columnar crystals parallel to each other in the direction perpendicular to the mold wall. In the center of the casting, the heat dissipation has no significant directionality, and can grow freely in all directions until they contact each other, so an equiaxed crystal area is formed. It can be seen that the organization in the casting is uneven, and generally speaking, the grains are relatively coarse. Therefore, when the amount of material used is increased, the volume and weight of the saddle trough become larger, the internal heat dissipation becomes more difficult, and its strength has an upper limit, which cannot match the existing steel cables above 2000MPa. In this solution, the saddle trough bottom plate is forged, and the forging process is hammering, annealing and other processes at high temperature. Its internal structure is uniform and the strength is higher, which can ensure the reliability of strength and can match the existing cables above 2000MPa.

[0016] 3. In the prior art, the saddle groove is cast as one piece, so the side wall plate of the saddle groove and the bottom plate of the saddle groove are made of the same material. However, the side wall plate of the saddle groove is not the main load-bearing part, and using the same material as the bottom plate causes waste and its cost is also higher. In the present application, the side wall plate and the saddle groove are separated, the bottom plate is forged with an alloy material that meets the requirements, and the side wall plate is made of high-strength steel plate, which is welded as a whole later. This fully reflects the "design principle of using good steel on the blade"; it can simplify the process and reduce processing costs.

[0017] 4. The bottom plate of the trough bears the pressure of the steel cable and disperses the force. Based on its force requirements, the bottom plate of the saddle trough is designed as an arc structure; therefore, if the bottom plate of the trough is to be forged directly into an arc structure, a forging die must be used. However, the structural dimensions of the saddle are usually designed according to the structure and span of the bridge. Generally, only 4 sets of saddles with the same structural dimensions are produced, that is, the manufacturing and production of the saddle does not meet the conditions of mass production. Forging dies are usually an effective means of mass production to improve efficiency and reduce costs, and the cost of forging dies is high, especially for large forging dies. Therefore, it is too expensive to use forging dies to forge the bottom plate of the trough; based on cost considerations, this scheme adopts a die-free forging method, that is, a press is directly used to forge the raw materials into a rectangular billet similar to the shape of the saddle trough bottom plate, and then the shape is formed with mechanical processing, which reduces the investment in dies.

[0018] 5. Since the cable saddle groove bottom plate is an arc-shaped structure, the cable saddle groove bottom plate is forged as a whole and formed into a shape by mechanical processing. The rectangular blank needs to be cut a lot, which will lead to a lot of material waste. Therefore, in this scheme, the cable saddle groove bottom plate is forged in sections, and each section is welded to form a complete cable saddle groove bottom plate after rough machining; the curvature of each section is reduced, and the material cutting amount can be reduced, thereby reducing material waste. On the other hand, the cable saddle structure is large in size, and the one-piece forging of the cable saddle groove bottom plate requires a whole piece of forged steel for forging and forming, which also increases the procurement and acquisition cost of forged steel.

[0019] 6. The bottom plate of the saddle groove is composed of multiple sections welded together. During the welding process, there will inevitably be errors, and the steps formed at the joints of each section will form a relatively concentrated extrusion stress on the steel cable, thus having an adverse effect on the steel cable; therefore, after the assembly of this scheme is completed, the bottom plate of the saddle groove is mechanically finished to avoid the possibility of steps during flat welding, making the overall smooth, not easy to produce extrusion pressure points, and its structure is more reliable.

[0020] Furthermore, the side wall plate in step 4 is forged using Q345R steel.

[0021] In terms of material selection, if the saddle groove is cast, in order to weld it with the saddle later, the saddle groove is generally made of weldable cast steel; and the highest material strength grade of weldable cast steel is ZG340-550H, and its yield strength is not less than 340MPa. The main saddle at this strength is seriously mismatched with the high-strength cast steel wire. And there are only four types of casting materials that meet the requirements of the saddle and meet the standards: ZG230-450H, ZG270-480H, ZG300-500H, and ZG340-550H. After adopting the forging process, there are as many as 75 materials that meet the requirements, including 15 carbon steel forgings and 60 alloy steel forgings. This provides more possibilities for designing and manufacturing high-strength and high-performance saddles.

[0022] Further, the forging process in step 1 is as follows: step a: put on a 3500-ton press, control the initial forging temperature at 1220°C, and the final forging temperature at 850°C, and perform chamfering, riser removal and other corrections on the steel ingot before returning to the heating furnace for further heating; step b: put on a 3500-ton press, control the initial forging temperature at 1220°C, and the final forging temperature at 850°C, and perform roughing, drawing and billeting on the billet before returning to the heating furnace for further heating; step c: put on a 3500-ton press, control the initial forging temperature at 1220°C, and the final forging temperature at 850°C, and perform roughing, drawing and billeting on the billet before returning to the heating furnace for further heating; Ton press, the initial forging temperature is controlled at 1220℃, the final forging temperature is controlled at 850℃, the blank is subjected to the second upsetting and drawing and then returned to the heating furnace for further heating; step d: put on the 3500 ton press, and then draw, trim and shape it, and then put it into the annealing furnace for insulation and waiting for the material; step e: after the planned number of products loaded in the annealing furnace is completed, start the normalizing + tempering heat treatment process, the normalizing temperature is controlled at 880±15℃, and the tempering temperature is controlled at 650±10℃.

[0023] Furthermore, in step 3, the welding is performed by submerged arc automatic welding, and the cladding metal performance of the welding wire is not lower than that of the welding base material. After the welding is completed, the weld and its two sides are heated to about 350° C., kept warm for 2-3 hours, and then cooled naturally.

[0024] Furthermore, the welding in step 4 adopts CO2 gas shielded welding, and the purity of CO2 gas is greater than 99.5%.

[0025] Furthermore, the segmented trough bottom plate in step 1 is divided into 3 sections. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention is a flow chart of the saddle groove forming process according to an embodiment of the present invention;

[0027] Figure 2 This is the finite element extrusion analysis diagram of ZG270-480H casting;

[0028] Figure 3 This is the finite element extrusion analysis diagram of ZG300-500H casting;

[0029] Figure 4 This is the finite element extrusion analysis diagram of 30CrMo forged steel;

[0030] Figure 5 This is the indentation distribution diagram of the extrusion test of 30CrMo forged steel specimen. DETAILED DESCRIPTION

[0031] The following is further described in detail through specific implementation methods:

[0032] The reference numerals in the drawings of the specification include: side wall plate 1, groove bottom plate 2, saddle groove 3.

[0033] Implementation example Figure 1 As shown:

[0034] Step 1:

[0035] Forging: according to the designed structural dimensions of the groove bottom plate 1 of the cable saddle groove 3, the groove bottom plate 2 of the cable saddle groove is divided into three segmented groove bottom plates, and an alloy block with a volume larger than the segmented groove bottom plate is selected for forging, and the alloy block is forged into a blank having a rectangular shape with the segmented groove bottom plate of the cable saddle groove bottom plate;

[0036] The trough bottom plate 2 uses 30CrMo grade forged steel ingot as raw material. The steel ingot is required to be smelted in electric arc furnace (EAF) + ladle refining (LF) + vacuum deoxidation (VD) + argon protection casting; the saddle trough bottom plate is forged in three sections.

[0037] In terms of material selection, if the saddle groove is cast, in order to weld it with the saddle later, the saddle groove is generally made of weldable cast steel; and the highest material strength grade of weldable cast steel is ZG340-550H, and its yield strength is not less than 340MPa. The main saddle at this strength is seriously mismatched with the high-strength cast steel wire. And there are only four types of casting materials that meet the requirements of the saddle and meet the standards: ZG230-450H, ZG270-480H, ZG300-500H, and ZG340-550H. After adopting the forging process, there are as many as 75 materials that meet the requirements, including 15 carbon steel forgings and 60 alloy steel forgings.

[0038] This application takes into account that the saddle groove directly bears the pressure of the steel cable. In the material selection experiment, in order to match the 2000MPa grade steel cable wire, the yield strength of the forged steel material should reach a target of no less than 390MPa. Based on previous work experience, engineers conducted a comparative study on the strength indicators of forged steel materials required for forged and welded combined saddles for 30CrMo, 20CrMnMo and 20CrNiMo. The results show that the forged steel 30CrMo material has a gentler slope while meeting the strength index requirements. The material has relatively consistent mechanical properties from the core to the surface, and can be used as the preferred forged steel material for the saddle. At the same time, the impact resistance of the 30CrMo material under different low temperature conditions was further studied, and the material has relatively excellent low temperature toughness. The test results of forged steel 30CrMo+Q420qE welding test plates show that the MT test of the welding evaluation test plate meets the requirements of GB / T 26952-2011 Level 1, and the UT test meets the requirements of NB / T47013.3-2015 Level I. The performance of the structural welds meets the requirements of high-performance forged and welded combined saddles, forming a good quality benefit.

[0039] By using different types of raw cast steel components and 30CrMo forged steel for finite element analysis and three-coordinate cable strand and saddle groove extrusion tests, the following conclusions were obtained:

[0040] (1) The order of indentation depth is: 30CrMo < ZG300-500H < ZG270-480H. The finite element analysis results of the indentation depth of the forging 30CrMo are relatively more uniform.

[0041] (2) The order of the number of plastic deformation elements entered is 30CrMo < ZG300-500H < ZG270-480H.

[0042] (3) Among the three research materials, the forged steel 30CrMo material has better anti-extrusion deformation ability, higher surface hardness, and its cost is also the steel to be considered first. It can be used as the forged steel material for the pressure-bearing component of the tank bottom plate.

[0043] After selecting the alloy material for forging the tank bottom plate, the following forging process is carried out:

[0044] Step a: Use a 3500-ton press. Control the initial forging temperature at 1220 °C and the final forging temperature at 850 °C. After chamfering and removing the riser of the ingot, return it to the heating furnace for continued heating.

[0045] Step b: Use a 3500-ton press. Control the initial forging temperature at 1220 °C and the final forging temperature at 850 °C. After upsetting and drawing out the billet to make the blank, return it to the heating furnace for continued heating.

[0046] Step c: Use a 3500-ton press. Control the initial forging temperature at 1220 °C and the final forging temperature at 850 °C. After upsetting and drawing out the billet for the second time to make the blank, return it to the heating furnace for continued heating.

[0047] Step d: Use a 3500-ton press. After further drawing out and trimming to form, put it into the annealing furnace for heat preservation and waiting for materials.

[0048] Step e: When the planned number of products in the annealing furnace is completed, start to execute the normalizing + tempering heat treatment process. Control the normalizing temperature at 880 ± 15 °C and the tempering temperature at 650 ± 10 °C.

[0049] In the existing forging process of 30CrMo forged steel, the forging temperature is generally selected between 1100℃-850℃ in the normalizing or tempering state. However, the saddle groove bottom plate blank is large in size and heavy in weight, and it is difficult to transfer it between the heating furnace and the press, and it is even more difficult to transfer it repeatedly; therefore, increasing the interval value of the initial forging temperature and the terminal temperature, maintaining the forging temperature for a longer time during the press operation, can reduce the number of transfers of the blank during the forging process. Secondly, the heavy weight and high thickness of the blank also lead to slow internal temperature rise of the material. Therefore, appropriately increasing the heating temperature is conducive to increasing the internal heating rate. In addition, the surface temperature of the blank is increased by utilizing the temperature gradient inside and outside the blank. The impact on the material is mainly reflected in the reduction of the strength performance of the material surface. However, on the one hand, since the forging block is the blank of the saddle groove bottom plate, the surface material will be mechanically cut in the later stage, and the impact is relatively small. On the other hand, the saddle groove bottom plate is in direct contact with the steel cable, and its surface strength requirement is lower than that of the steel cable, which is beneficial to the steel cable and avoids damage to the steel cable. The saddle groove forged at this temperature shows good matching performance with the steel cable in the indentation test with the steel cable.

[0050] Step 2:

[0051] Rough machining: rough machining the blank according to the arc shape of the segmented groove bottom plate of the saddle groove 3, so that the blank forms an arc structure consistent with the segmented groove bottom plate;

[0052] The CNC boring and milling machine with a rotary table is used for processing in a four-axis linkage mode. During processing, the rotary table drives the parts to rotate synchronously and continuously changes the orientation of the parts, so that the bottom plane of the tool and the bottom surface of the cable groove arc are always kept in a state of being nearly flat when the spindle is cutting, thereby effectively removing the root residue.

[0053] In order to ensure the position requirements of the cable groove and the saddle body and facilitate processing, clamping and correction, the reference plane is first processed and then the reference plane is used; Machine tool: CNC boring and milling machine TK6920 with a large rotary CNC linked rotary table.

[0054] Step 3:

[0055] Groove bottom plate welding: weld the three sections of rough-machined segmented groove bottom plates to form a rough-machined groove bottom plate;

[0056] Since the segmented bottom plate of the saddle trough is forged from 30CrMo forgings, the butt joint between the rough-machined segmented bottom plates is welded using a narrow gap submerged arc welding special automatic welding equipment and submerged arc welding. The cladding metal performance of the welding wire cannot be lower than that of the parent material. The material of the bottom plate of the trough is 30CrMo, so the metal properties of the welding wire need to meet the following requirements:

[0057] Yield strength(MPa) Tensile strength(MPa) Elongation after break (%) Impact energy (J) ≥390 ≥590 ≥15 KU2≥44

[0058] Before welding, harmful substances such as rust, iron oxide, oil, moisture, etc. must be thoroughly removed from the area to be welded so that the surface can reveal a metallic luster.

[0059] The arc must be started and extinguished on the lead plate 80mm away from the designed weld end during submerged arc automatic welding. The arc should not be broken during the welding process. If the arc is broken, the arc stop point must be planed into a 1:5 slope, overlapped by 50mm, and then the arc is started and welded. The overlap should be polished and smoothed after welding.

[0060] The butt joint of 30CrMo forgings is automatically welded with special equipment for narrow gap submerged arc welding. Before formal welding, welders should practice repeatedly to improve their familiarity with the equipment and welding experience. Special anti-deformation tooling is made to rigidly fix the workpiece to prevent deformation of the workpiece due to welding shrinkage and insufficient processing allowance. The process requirements are strictly followed during the welding process. After each weld, an extended air shovel must be used for vibration elimination to reduce welding stress. At the same time, the welding slag can be thoroughly removed to prevent slag inclusion and other problems when welding the next weld.

[0061] In order to eliminate or reduce welding residual stress, soften the hardened structure of the welding heat affected zone, improve the toughness of the welded joint, promote the escape of residual hydrogen, improve the geometric stability of the structure, and enhance the ability of the joint to resist stress corrosion. During the entire welding process, an intermediate stress relief heat treatment is required after the segmented groove bottom plate is butt-jointed. After welding is completed, the whole is subjected to post-weld annealing stress relief heat treatment, and finally the heat preservation and slow cooling are carried out to prevent the generation of cold cracks. The weld and its two sides are heated to about 350℃, kept warm for 2-3 hours, and then cooled naturally.

[0062] All welds must be visually inspected over the entire length and must not have defects such as cracks, lack of fusion, slag inclusions, unfilled arc pits and weld nodules. They must comply with the regulations and be subjected to non-destructive testing of the welds.

[0063] Step 4:

[0064] Side wall plate welding: welding the side wall plate 1 on the rough-machined groove bottom plate to form a rough-machined saddle groove;

[0065] The side wall plate is forged from Q345R steel and welded to both sides of the rough-machined groove bottom plate. CO2 gas shielded welding is used in the welding process, and the welding material is solid welding wire commonly used for welding low-alloy high-strength steel. The metal properties of the welding wire need to meet the following requirements:

[0066]

[0067] The rust on the welding wire and the dirt in the flux must be cleaned; the purity of CO2 gas should be greater than 99.5%. The welding position should be preheated before welding, and the welding groove and surrounding areas should be preheated with a natural gas flame. The preheating area is centered on the weld, and the single-side width is not less than 2 times the plate thickness and not less than 75mm. The preheating temperature of the steel plate butt should reach the range of 100-150℃. The purpose of preheating is to slow down the temperature gradient and cooling rate when the weld joint is heated, and appropriately extend the cooling time in the range of 800-500℃, so as to reduce or avoid the formation of hardened structure, reduce welding stress and deformation, facilitate the escape of hydrogen, and prevent the formation of cracks.

[0068] Step 5:

[0069] Finishing: The rough-machined saddle groove is machined to a saddle groove that is consistent with the designed size.

[0070] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A forming process of a forged and welded saddle trough, wherein the saddle trough comprises a forged trough bottom plate and a side wall plate, and is characterized in that: The forging welding process includes the following steps: Step 1: Forging: According to the designed structural dimensions of the bottom plate of the saddle trough, the bottom plate of the saddle trough is divided into 2-3 segmented bottom plates, and an alloy block made of 30CrMo alloy structural steel is selected for forging, and the alloy block is forged into a rectangular blank larger than the size of the segmented bottom plate; Step 2: Rough machining: Rough machining the rectangular blank according to the arc shape of the saddle groove segmented groove bottom plate, so that the blank forms an arc structure consistent with the segmented groove bottom plate; Step 3: Groove bottom plate welding: fix and connect the three rough-machined segmented groove bottom plates into a rough-machined groove bottom plate; Step 4: Side wall plate welding: weld the side wall plate on the rough-machined groove bottom plate to form a rough-machined saddle groove; Step 5: Finishing: The rough-machined saddle groove is machined to a saddle groove that is consistent with the designed size.

2. The forming process of the forged-welded saddle groove according to claim 1 is characterized in that: The side wall plate in step 4 is forged using Q345R steel.

3. The forming process of the forged-welded cable saddle groove according to claim 1, characterized in that: The forging process in step 1 comprises the following steps: Step a: put the steel ingot on a 3500 ton press, control the initial forging temperature at 1220°C, and the final forging temperature at 850°C, perform chamfering, riser removal and other corrections on the steel ingot, and then return it to the heating furnace for further heating; Step b: put the blank into a 3500 ton press, control the initial forging temperature at 1220°C, and the final forging temperature at 850°C, and then return the blank to the heating furnace for further heating after roughing and drawing. Step c: put the blank into a 3500 ton press, control the initial forging temperature at 1220°C, and the final forging temperature at 850°C, perform a second upsetting and drawing process on the blank, and then return to the heating furnace for further heating; Step d: Put it on a 3500-ton press, then stretch it, trim it and shape it, and then put it into an annealing furnace for insulation and waiting for the material; Step e: After the planned number of products to be loaded into the annealing furnace is completed, the normalizing + tempering heat treatment process is started. The normalizing temperature is controlled at 880±15℃, and the tempering temperature is controlled at 650±10℃.

4. The forming process of the forged-welded saddle groove according to claim 1, characterized in that: In step 3, the welding is performed by submerged arc automatic welding, and the cladding metal performance of the welding wire is not lower than that of the welding base material. After the welding is completed, the weld and the surrounding areas on both sides are heated to about 350° C., kept warm for 2-3 hours, and then cooled naturally.

5. The forming process of the forged-welded cable saddle groove according to claim 1, characterized in that: The welding in step 4 is performed by CO2 gas shielded welding, and the purity of the CO2 gas is greater than 99.5%.

6. The forming process of the forged-welded cable saddle groove according to claim 1, characterized in that: The segmented trough bottom plate in step 1 is divided into 3 sections.

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