CN112296228A - Three-piece type flange ball valve cover rolling die - Google Patents

Three-piece type flange ball valve cover rolling die Download PDF

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Publication number
CN112296228A
CN112296228A CN202011149564.3A CN202011149564A CN112296228A CN 112296228 A CN112296228 A CN 112296228A CN 202011149564 A CN202011149564 A CN 202011149564A CN 112296228 A CN112296228 A CN 112296228A
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China
Prior art keywords
ring
blank
degrees
roller
conical
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Pending
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CN202011149564.3A
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Chinese (zh)
Inventor
周亚夫
吴克成
杨柳
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Sichuan Hongxin Energy Equipment Manufacturing Co ltd
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Sichuan Hongxin Energy Equipment Manufacturing Co ltd
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Priority to CN202011149564.3A priority Critical patent/CN112296228A/en
Publication of CN112296228A publication Critical patent/CN112296228A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21HMAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS
    • B21H1/00Making articles shaped as bodies of revolution
    • B21H1/06Making articles shaped as bodies of revolution rings of restricted axial length

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Forging (AREA)

Abstract

The invention discloses a three-piece type rolling die for a valve cover of a flange ball valve, which comprises a main roller part, a core roller, an upper conical roller of a hole expanding machine and a lower conical roller of the hole expanding machine, wherein the part of the core roller, which penetrates through a blank, consists of a lower cylindrical section, a conical transition section with a large upper part and a small lower part and an upper cylindrical section which are sequentially connected from bottom to top, the main roller part comprises a main roller shaft, a lower cover ring, a spacer ring, a middle ring, the spacer ring and an upper cover ring, the part of the lower end surface of the upper cover ring, which protrudes out of the spacer ring, is a double conical surface consisting of a lower conical surface and an upper conical surface, the included angle between the lower conical surface and the horizontal plane is more than or equal to 5 degrees and less than or equal to 8 degrees, the included angle between the upper conical surface and the horizontal plane is more than or equal to 35 degrees and less than or equal to 42 degrees, the included angle between the lower end surface of the. The upper flange of the blank after the rolling forming is provided with a step, and one end of the inner hole close to the upper flange is provided with a taper, so that the subsequent machine dosage is reduced, the material cost is reduced, and the forging quality is improved.

Description

Three-piece type flange ball valve cover rolling die
Technical Field
The invention relates to the technical field of forging forming dies, in particular to a three-piece type flange ball valve cover rolling die.
Background
The rolling is a rotary forging method for manufacturing the required ring-shaped piece by gradually enlarging the diameter of the ring-shaped blank in a hole pattern formed by a rolling roller and a core roller and forming the ring-shaped blank, which is also called reaming or rolling.
FIG. 1 is a part diagram of a valve cover of a medium-sized and large-sized three-piece flange ball valve, wherein a flange plate at the upper end of the valve cover is provided with a step, and the upper end of an inner hole is provided with a step hole. Fig. 2 is a blank drawing of a valve cover of a medium-sized and large-sized three-piece flange ball valve with a conventional design after being formed by rolling and forging. The flange plate at the upper end of the valve cover forging rolled by the rolling die has no step and is an integral plane; meanwhile, the inner hole is also a straight hole.
At present, the process of rolling, forging and forming a three-piece flange ball valve cover is shown in fig. 3. Mainly comprises (I) blanking, heating and upsetting; secondly, blank making and continuous skin punching; and (III) a rolling forming process, wherein the inner hole of the blank after blank making and continuous skin punching is a straight hole, the flange plate at the upper end of the rolled blank is a plane, and the inner hole is still the straight hole. The rolling die used in the rolling forming is shown in fig. 4.
The rolling die consists of a main roller part, a core roller 8, an upper cone roller 9 of the broaching machine and a lower cone roller 7 of the broaching machine. The core roller 8 is used for sleeving the blank, and the part of the core roller 8 penetrating through the blank is a cylindrical section. The upper cone roller 9 of the broaching machine and the lower cone roller 7 of the broaching machine are respectively arranged on one side of the axis of the core roller 8 and are used for pressing the upper end surface and the lower end surface of the blank. The main roller part is arranged on the other side of the axis of the core roller 8 and is combined with the core roller 8 for rolling the blank, the main roller part comprises a main roller shaft 1, and a lower cover ring 2, a spacing ring 3, a middle ring 4 and a spacing ring 3 which are sequentially coaxially sleeved on the main roller shaft 1 from bottom to top, and are pressed and fixed through a pressing ring 6; the diameters of the lower cover ring 2, the middle ring 4 and the upper cover ring 5 are larger than the diameter of the spacer ring 3, the parts of the upper end surface of the lower cover ring 2 and the upper end surface of the middle ring 4, which protrude out of the spacer ring 3, are conical surfaces, the lower end surface of the blank is positioned in the height range of the conical surface of the lower cover ring 2, and the upper end surface of the blank is positioned outside the pressing ring 6.
Although the structure of the die is relatively simple, the service life of the rolling die for the valve covers of medium-sized and large-sized three-piece flange ball valves is long, and except for the core rod, the service life of one die is more than 4 thousands of dies, and the height of the die can reach 10 thousands of dies. The service life of the core roller is about 4000, so that the cost difference of the die cost which is spread on each forging blank is very small and can be almost ignored. However, in the forged piece formed by rolling the valve cover of the medium-sized and large-sized three-piece flange ball valve with the conventional design, the flange plate at the upper end has no step, and the end, close to the upper flange plate, of the inner hole has no taper, so that the subsequent machining cost is high, and the material cost of blank blanking is greatly increased.
Disclosure of Invention
The invention aims to provide a ring rolling die suitable for a three-piece flange ball valve cover, which can enable an upper flange of a ring-rolled blank to be provided with a step and one end of an inner hole close to the upper flange to be provided with a taper, thereby reducing the subsequent machining dosage and reducing the material cost.
Therefore, the technical scheme adopted by the invention is as follows: a three-piece type flange ball valve cover ring rolling die comprises a main roller part, a core roller, an upper cone roller of a ring rolling machine and a lower cone roller of the ring rolling machine, wherein the core roller is used for sleeving a blank, the part of the core roller, which penetrates through the blank, consists of a lower cylindrical section, a conical transition section with a large upper part and a small lower part and an upper cylindrical section which are sequentially connected from bottom to top; the diameter of the lower cover ring, the diameter of the middle ring and the diameter of the upper cover ring are larger than the diameter of the spacer ring, the parts of the upper end surface of the lower cover ring and the lower end surface of the middle ring, which protrude out of the spacer ring, are conical surfaces, the part of the lower end surface of the upper cover ring, which protrudes out of the spacer ring, is a double conical surface consisting of a lower conical surface and an upper conical surface, the included angle between the lower conical surface and the horizontal plane is not less than 5 degrees and not more than 8 degrees, the included angle between the upper conical surface and the horizontal plane is not less than 35 degrees and not more than 42 degrees, the included angle gamma of the conical transition section is not more than 64 degrees, the lower end surface of the blank is located in the height range of the conical.
Preferably, in the above aspect, an angle α between the lower tapered surface and the horizontal plane is 5 °, and an angle β between the upper tapered surface and the horizontal plane is 42 °.
More preferably, the height of the upper cylindrical section of the core roller extending into the blank is 10mm, and the included angle gamma of the conical transition section is 40 degrees. The included angle is determined by the structure of the final product, and the maximum taper angle gamma is less than or equal to 64 degrees according to the result of digital simulation rolling.
More preferably, the included angle between the upper end surface of the lower cover ring and the horizontal plane is 2.5 degrees.
The invention has the beneficial effects that: the upper end flange step of the valve cover and the upper end taper of the inner hole can be rolled and formed at one time during reaming through the rolling die, and key parameters (including the angle of the double conical surfaces, the structure of the core rod, the height relation between the upper end surface and the lower end surface of the blank and the tapered surfaces of the upper cover ring and the lower cover ring and the like) in the rolling process are controlled by adding the upper cover ring with the double conical surfaces in the rolling die, so that the process feasibility is high, and the quality of the rolled and forged piece is improved. This kind of valve gap, production quantity is big, and the die design after the optimization has greatly reduced machine dosage and material cost, can bring huge economic benefits.
Drawings
Fig. 1 is a part view of a three-piece flange ball valve cover.
Fig. 2 is a diagram of a blank of a conventional three-piece flange ball valve cover formed by rolling forging.
Fig. 3 is a process diagram for rolling, forging and forming a valve cover of a conventional three-piece flange ball valve.
Fig. 4 is a rolling die of a conventional three-piece flange ball valve cover.
Fig. 5 is a diagram of a blank of the three-piece flange ball valve cover formed by rolling and forging.
FIG. 6 is a process diagram for the rolling forging of the valve cover of the three-piece flange ball valve.
FIG. 7 is a blank making die for the rolling forging of the three-piece flange ball valve cover of the invention.
FIG. 8 is a ring rolling die for ring rolling and forging a three-piece flange ball valve cover according to the present invention.
Detailed Description
The invention will be further illustrated by the following examples in conjunction with the accompanying drawings:
the three-piece flange ball valve cover component shown in fig. 1 is typically characterized by an upper flange and a lower flange, wherein the upper flange is provided with a step, and the upper end of an inner hole is provided with a stepped hole. Firstly, a three-piece flange ball valve cover blank as shown in fig. 5 needs to be forged and machined.
The roll-expanding forging forming process adopted by the three-piece flange ball valve cover blank shown in fig. 5 comprises the following steps: blanking, heating and upsetting; secondly, blank making and continuous skin punching; and (III) rolling and shaping, as shown in figure 6. The blank of the valve cover of the three-piece flange ball valve shown in figure 5 is provided with an upper flange, a lower flange and a central through hole, wherein one end of the central through hole close to the upper flange is provided with a taper, and the upper flange is provided with a step.
In the step (I), blanking is carried out by adopting a band sawing machine according to the specification, the size and the precision required by the blanking process. The heating is carried out by adopting a heat accumulating type natural gas heating furnace according to the heating process file strictly, so that the height of the temperature rise, the temperature control, the sectional temperature rise during the stainless steel heating, the heat preservation requirement and the like is consistent with the height of the process file. After heating to the forging temperature, upsetting is performed. But not limited to, a band saw machine, and a circular saw machine may be used. The heating is not limited to the regenerative natural gas heating furnace, and may be an electric heating furnace or the like.
As shown in fig. 7, the blank making and the punching of the integral skin share a set of dies, including a blank making lower die assembly 10, a punching punch 11 and an integral skin punch 12.
In the step (II), the blank after upsetting is placed into a blank making lower die assembly 10, and a conical deep blind hole is punched in the center of the blank through a conical punching punch 11 with a large upper part and a small lower part; the blank is taken out and turned for 180 degrees, then is placed into the blank making lower die assembly 10 again, and the continuous skin layer is punched through the continuous skin punch 12, so that the conical deep blind hole in the center of the blank is changed into a central through hole, and preparation is made for subsequent roll forming.
As shown in fig. 8, the rolling die is mainly composed of a main roll part, a core roll 8, an upper reamer cone roll 9 and a lower reamer cone roll 7. The core roller 8 is used for sleeving the blank, and the part of the core roller 8 penetrating through the blank consists of a lower cylindrical section 8a, a conical transition section 8b with a large upper part and a small lower part and an upper cylindrical section 8c which are sequentially connected from bottom to top. The upper cone roller 9 of the broaching machine and the lower cone roller 7 of the broaching machine are respectively arranged on one side of the axis of the core roller 8 and are used for pressing the upper end surface and the lower end surface of the blank. The main roll part is arranged on the other side of the axis of the core roll 8 and is combined with the core roll 8 to roll the blank. The middle part of the core stick 8 is additionally provided with a step section with taper so as to be matched with the inner hole structure of the blank.
The main roller part mainly comprises a main roller shaft 1, a lower cover ring 2, a space ring 3, a middle ring 4, a space ring 3 and an upper cover ring 5 which are sequentially coaxially sleeved on the main roller shaft 1 from bottom to top, and is pressed and fixed through a pressing ring 6. The diameters of the lower cover ring 2, the middle ring 4 and the upper cover ring 5 are larger than the diameter of the spacer ring 3, and the parts of the upper end surface of the lower cover ring 2 and the upper end surface and the lower end surface of the middle ring 4 which protrude out of the spacer ring 3 are conical surfaces. The part of the lower end surface of the upper cover ring 5, which protrudes out of the spacer ring 3, is a double conical surface consisting of a lower conical surface 5b and an upper conical surface 5a, the included angle between the lower conical surface 5b and the horizontal plane is more than or equal to 5 degrees and less than or equal to 8 degrees, and the included angle between the upper conical surface 5a and the horizontal plane is more than or equal to 35 degrees and less than or equal to 42 degrees. The included angle gamma of the conical transition section 8b is less than or equal to 64 degrees. The lower end surface of the blank is located within the height range of the tapered surface of the lower cover ring 2, and the upper end surface of the blank is located within the height range of the upper tapered surface 5a of the upper cover ring 5.
Preferably, the angle α between the lower tapered surface 5b and the horizontal plane is 5 °, and the angle β between the upper tapered surface 5a and the horizontal plane is 42 °. The upper cylindrical section 8c of the core roller 8 extends into the blank by a height of 10mm, and the angle γ of the conical transition section 8b is 40 °. The upper end surface of the lower cover ring 2 forms an included angle of 3 degrees with the horizontal plane.
The blank after the rolling and expansion of the rolling and expansion die is provided with an upper flange, a lower flange and a central through hole, one end of the central through hole close to the upper flange is provided with a taper, and the upper flange is provided with a step, as shown in figure 5.
In the third step, the blank is placed into a rolling die shown in fig. 8 for rolling and forming.
Preferably, in step (iii), a horizontal numerically controlled broaching machine with axial rolling is used. The blank is placed on a workbench of a hole expanding machine, a core roller 8 is sleeved in an inner hole of the blank, a main roller part rotates, the core roller 8, an upper conical roller 9 of the hole expanding machine and a lower conical roller 7 of the hole expanding machine simultaneously move towards the main roller part, simultaneously, after the upper conical roller 9 of the hole expanding machine moves downwards to a proper position, the inner hole and the outer circle of the blank are gradually expanded under the combined action of the core roller 8 and the main roller part, the total height of the blank is ensured by the downward movement of the upper conical roller 9 of the hole expanding machine, after all sizes and shapes of the blank meet requirements, the upper conical roller 9 of the hole expanding machine, the lower conical roller 7 of the hole expanding machine and the core roller 8 return to original positions, the blank.
Preferably, the three-station double-workbench 2000-ton hydraulic forging press is shared in the step (I) and the step (II). The three stations comprise a first station, a second station and a third station, and the second station is a working station and is positioned in the center of the press. A platform is arranged on the workbench No. 1, and a blank making lower die assembly is arranged on the workbench No. 2.
Placing the blank on a No. 1 workbench at a first station, and moving the No. 1 workbench into a second station for upsetting and descaling; after the blank is clamped, the No. 1 workbench moves to a third station, and the No. 2 workbench moves to a second station and enters a working position; a blank making lower die assembly is arranged on the No. 2 workbench, a blank is placed in the blank making lower die assembly, a punching punch moves to the center of a second station, a conical deep blind hole is punched downwards in the center of the blank, and the punching punch is reset; ejecting the blank, clamping the blank, turning the blank by 180 degrees, putting the blank into a blank-making lower die assembly, moving a continuous skin punch to the central position of a second station, punching off a continuous skin layer downwards, and resetting the continuous skin punch; the No. 2 workbench moves to a third station, a blank is ejected out, and the blank is taken away; and circularly entering upsetting, blank making and continuous punching of the next blank.
After the rolling and expanding formation, before machining, blank inspection, heat treatment (tempering, and solution treatment for stainless steel materials), comprehensive inspection, and warehousing for transfer are required to be performed, which is not described herein again, and the method only explains the core important steps.
Compared with the traditional process method, the process method has the advantages that due to the change of the die, the blanking weight of the blank after the improved design is 406Kg, the blanking weight of the blank after the conventional design is 438.4Kg, the weight of the material after the optimized design is reduced by 32.4Kg, and the material is saved by 7.4 percent, so that the process method is very considerable.
The key point of the annual ring rolling die design is as follows:
(1) the design of the upper cover ring of the ring rolling die is very important, the design of the double conical surfaces at the lower end of the upper cover ring is critical, and the perfect forming of the steps on the upper flange plate of the valve cover forging is related, so that the defect of forging (ring rolling) is avoided. When the included angle beta between the upper conical surface 5a and the horizontal plane is larger than 42 degrees, the deformation acting force of the upper cover ring on the blank is too large, upward axial burrs are generated at the contact position of the upper end of the blank and the upper cover ring, and then the burrs are rolled on the upper end surface through the rolling action of the upper conical roller 9 of the hole expanding machine to form an interlayer. The angle is therefore designed to be 42 ° or slightly less than 42 °. This structure has an additional advantage: the height requirement on the blank is wide, and the blank can be placed in the vertical height range of the angle of the height dimension of the workbench of the hole expanding machine, so that the operation and control capability of the height control of the blank during blank manufacturing is reduced, and the precision control requirement of equipment and the requirement of the technical level of workers are reduced. When the included angle between the lower conical surface 5B of the upper cover ring 5 and the horizontal plane is alpha less than 5 degrees, the position of the beta angle is firstly contacted with the blank, the metal of the blank flows along the direction of the angle B, the metal cannot be contacted with the conical surface of the alpha angle in the upper cover ring in the early stage, and a circle of annular groove is generated at the position during final forming, so that the forging (rolling) defect is formed. Therefore, α in the upper cover ring needs to be designed to be 5 ° or more.
(2) The design of the core rod 8 is also important, the key point is that a position corresponding to the upper end of the upper taper hole of the inner hole of the blank, namely, a small section of the upper cylindrical section 8c is required to extend into the workpiece to form a straight hole, and the straight hole has a very short size, but plays a very large role in the rolling and expanding stability in the rolling and expanding forming process. Because of the taper of the inner hole, the blank generates an axial force in the rolling process, and in the actual production process, because the main roller part of the rolling die and the contact surface between the core rod and the blank are very small during rolling, the blank can generate axial runout under the action of the axial force, thereby causing the generation of forging (rolling) defects. When the core rod is designed, the adverse factors need to be fully considered, so that a section of straight hole is formed in an inner hole at the upper end of the blank in the forming process, and the straight hole part is only acted by radial force, thereby effectively restraining the blank from jumping in the rolling process and avoiding the forging (rolling) defect caused by the blank jumping.

Claims (4)

1. The utility model provides a three-piece formula flange ball valve gap ring rolling die, includes that core roll part, core roller (8) and reamer go up awl roller (9) and reamer lower cone roller (7), core roller (8) are used for suit blank, and the part that passes the blank on core roller (8) comprises lower cylinder section (8a), big-end-up's toper changeover portion (8b) and last cylinder section (8c) that link to each other in proper order from the bottom up, and reamer upper cone roller (9) and reamer lower cone roller (7) set up respectively in one side of core roller (8) axis and are used for pressing the upper and lower terminal surface at the blank, the main roll part sets up the opposite side of core roller (8) axis and combines core roller (8) to be used for carrying out the ring rolling to the blank, and the main roll part includes main roll axle (1) to and from the bottom up in proper order coaxial suit lower cover circle (2), spacer ring (3), well circle (4) on main roll axle (1), The space ring (3) and the upper cover ring (5) are pressed and fixed through a pressing ring (6); the diameter of the lower cover ring (2), the middle ring (4) and the upper cover ring (5) is larger than that of the spacer ring (3), the part of the upper end surface of the lower cover ring (2) and the part of the upper end surface of the middle ring (4) protruding out of the spacer ring (3) are conical surfaces, the part of the lower end surface of the upper cover ring (5) protruding out of the spacer ring (3) is a double conical surface consisting of a lower conical surface (5b) and an upper conical surface (5a), the included angle between the lower conical surface (5b) and the horizontal plane is greater than or equal to 5 degrees and less than or equal to 8 degrees, the included angle between the upper conical surface (5a) and the horizontal plane is greater than or equal to 35 degrees and less than or equal to 42 degrees, the included angle gamma of the conical transition section (8b) is less than or equal to 64 degrees, the lower end surface of the blank is located within the height range of the conical surface of the lower cover ring (2), and the upper.
2. The three-piece flange ball valve cover rolling die according to claim 1, characterized in that: the included angle between the lower conical surface (5b) and the horizontal plane is 5 degrees, and the included angle beta between the upper conical surface (5a) and the horizontal plane is 42 degrees.
3. The three-piece flange ball valve cover rolling die according to claim 1, characterized in that: the upper cylindrical section (8c) of the core roller (8) extends into the blank by 10mm, and the included angle gamma of the conical transition section (8b) is 40 degrees.
4. The three-piece flange ball valve cover rolling die according to claim 1, characterized in that: the included angle between the upper end surface of the lower cover ring (2) and the horizontal plane is 3 degrees.
CN202011149564.3A 2020-10-23 2020-10-23 Three-piece type flange ball valve cover rolling die Pending CN112296228A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011149564.3A CN112296228A (en) 2020-10-23 2020-10-23 Three-piece type flange ball valve cover rolling die

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011149564.3A CN112296228A (en) 2020-10-23 2020-10-23 Three-piece type flange ball valve cover rolling die

Publications (1)

Publication Number Publication Date
CN112296228A true CN112296228A (en) 2021-02-02

Family

ID=74327534

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011149564.3A Pending CN112296228A (en) 2020-10-23 2020-10-23 Three-piece type flange ball valve cover rolling die

Country Status (1)

Country Link
CN (1) CN112296228A (en)

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