Forming Die and Forming Method for a Large-Scale Titanium Alloy Ball Valve

Abstract

The present invention discloses a forming die and a forming method for a large-sized titanium alloy ball valve. The forming die includes an initial shaping die for forging and shaping a non-spherical ball valve blank into a quasi-spherical shape, and a final forging and shaping die for forging and shaping the quasi-spherical ball valve blank into a regular spherical shape. The initial shaping die includes a first upper die and a first lower die. A positioning mechanism is provided on the first lower die to drive the square-structured ball valve blank to make each of its side edges vertically correspond to the first upper die. A cylindrical arc surface is provided on the bottom surface of the first upper die. The initial shaping die further includes a second upper die and a second lower die, and shaping arc spherical surfaces are provided on both the upper and lower surfaces thereof. The final forging and shaping die includes a third upper die with a forming arc spherical surface provided on its lower surface, and further includes a support frame and a through-diameter forming rod inserted into the ball valve. Through the forming die of the present application for the processing and shaping of large-sized ball valve products, the raw material cost and processing cost can be greatly saved.

Description

Technical Field

[0001] The present invention relates to the field of forming technology for large-sized titanium alloy ball valves, and particularly relates to a forming die and a forming method for large-sized titanium alloy ball valves. Background Art

[0002] Ball valves are usually used for the regulation and control of fluids, to cut off, distribute, and change the flow direction of the medium. They can flexibly control the flow of the medium in pipelines. Multi-way ball valves can also achieve confluence, diversion, and flow direction switching. At the same time, any channel can be closed to connect the other two channels. Currently, ball valves are widely used in industries such as petroleum refining, long-distance pipelines, chemical engineering, pharmaceuticals, water conservancy, and municipal engineering. The main structure of a ball valve includes a plug body in the shape of a sphere, which has a circular through-hole or channel passing through its axis. The on-off of the ball valve can be achieved by rotating the valve core.

[0003] Since ball valves are usually used more for the on-off of fluids, in pipeline transportation in specific fields such as the chemical and pharmaceutical industries, due to the corrosion of the ball valve by the fluid, it is usually made of titanium alloy material with high corrosion resistance. And according to the pipeline diameter, a suitable titanium alloy ball valve is selected. For example, for a branch pipeline with a smaller diameter (such as 20 mm), a small-sized ball valve of a suitable specification is selected, and for the main pipeline (such as greater than 250 mm), a ball valve product of a suitable specification is also used.

[0004] When processing ball valves, the current processing method is to use a cylindrical blank larger than the finished ball valve specification, and form a spherical structure on its outer surface through turning processing, and then form a finished ball valve after processing the inner hole in its center. The processing time increases synchronously with the increase of the ball valve specification, as well as the tool cost and labor cost. For example, when processing ball valves applied to large pipelines such as deep sea (usually greater than 300 mm), the cost of turning processing is further prominent. On this basis, the waste of raw materials caused by turning processing is shown in the following table for comparison:

[0005]

[0006] It can be obtained from the table that for the ball valve with processing serial number 1, the weight of the cylindrical blank used is 95 kg, while the weight of the formed ball valve after processing is only 35.72 kg, resulting in a waste of 59.28 kg of raw materials during processing. When processing ball valves with specifications of serial numbers 2 - 5, with the increase of the ball valve size, the weight of the wasted materials during processing further increases (all greater than half of the blank weight), and at the same time, it also leads to an increase in processing time, and a synchronous increase in tool cost and labor cost. Therefore, in the current processing of ball valves, the processing cost of enterprises increases synchronously with the increase of the ball valve specification, and the profit decreases with the increase of the ball valve size. In addition, it results in a higher finished product price for large-sized ball valves, causing an increase in the later use cost of the ball valve. Summary of the Invention

[0007] In view of the above problems, the present invention aims to provide a forming die and a forming method for a large-sized titanium alloy ball valve, which can greatly save raw materials compared with the current turning processing, and also includes aspects such as reduction of processing time, cost of cutting tools, and increase of labor cost.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A forming die for a large-sized titanium alloy ball valve, characterized in that: the forming die includes an initial shaping die for forging and shaping a non-spherical ball valve blank into a quasi-spherical shape, and a final forging and shaping die for forging and shaping the quasi-spherical ball valve blank into a regular spherical shape.

[0009] Specifically, the non-spherical ball valve blank has a square structure, and the initial shaping die includes a first upper die and a first lower die. A positioning mechanism is provided on the first lower die to drive the square-structured ball valve blank to make its respective side edges vertically correspond to the first upper die. A cylindrical arc surface is provided on the bottom surface of the first upper die.

[0010] Specifically, the positioning mechanism is a wedge block that is symmetrically slidably arranged on the first lower die and fits against the side wall of the square-structured ball valve blank. Preferably, the wedge block is contact-adjusted and fixed by a fastening bolt passing through the side wall of the first lower die. At the same time, a right-angle groove and a right-angle block for closing it are also divided on the cylindrical arc surface.

[0011] Specifically, the initial shaping die further includes a second upper die and a second lower die, and shaping arc spherical surfaces are provided on both the upper and lower surfaces of the two.

[0012] Specifically, the final forging and shaping die includes a third upper die, on the lower surface of which a forming arc spherical surface is provided, and also includes a support frame, on which a through-diameter forming rod passing through the ball valve is horizontally rotatably supported.

[0013] A forming die and a forming method for a large-sized titanium alloy ball valve, characterized by including the following steps:

[0014] S1. Place the square-structured blank on the first lower die and fix it through the wedge block, and keep the side edges of the blank vertically corresponding to the first upper die. The first lower die presses down to forge the side edge parts into a quasi-arc structure;

[0015] S2. Rotate and adjust the position of the square blank, and forge each side edge into a quasi-arc structure to obtain a quasi-spherical blank;

[0016] S3. Place the quasi-spherical shape in the shaping arc spherical surface of the second lower die, and jointly shape it into a spherical-structured blank through the second upper die;

[0017] S4. Punch a hole to punch a through-diameter hole in the middle of the spherical-structured blank;

[0018] S5. Place the spherical structure blank after punching on the through - diameter forming rod and suspend it on the support frame. Through the rotational cooperation between the third upper die and the through - diameter forming rod, finally forge a regular ball valve.

[0019] The beneficial effects of the present invention are as follows: The mold used for forming the ball valve in this application can save more than 20% of the raw materials compared with the current turning processing in the publicly announced ball valve specifications. Moreover, as the ball valve specification increases, the proportion of the saved raw materials further increases. The turning processing also includes aspects such as an increase in processing time, tool wear, and an increase in labor costs. Therefore, for the processing and forming of large - specification ball valve products through the forming mold of this application, the raw material cost and processing cost can be greatly saved. When the ball valve processing is batch processing, the increase in the current turning processing cost will be further prominent compared with this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a diagram of the square blank of the present invention.

[0021] Figure 2 It is a diagram of placing the square blank between the first upper die and the first lower die of the present invention.

[0022] Figure 3 It is a top - view structural diagram of the first lower die of the present invention.

[0023] Figure 4 It is a diagram of the process of forging the square blank into a cylindrical blank of the present invention.

[0024] Figure 5 It is a diagram of the forged cylindrical blank of the present invention.

[0025] Figure 6 It is a diagram of placing the cylindrical blank between the second upper die and the second lower die of the present invention.

[0026] Figure 7 It is a diagram of forging the cylindrical blank into a spherical - like blank of the present invention.

[0027] Figure 8 It is a diagram of punching the spherical - like blank of the present invention.

[0028] Figure 9 It is a diagram of forging the spherical - like blank into a finished ball valve of the present invention.

[0029] Figure 10 For the present invention Figure 9 It is a diagram of the spherical - like blank sleeved on the through - diameter forming rod in

[0030] Figure 11 It is a diagram of the deformation of forging the spherical - like blank into a finished ball valve of the present invention.

[0031] In the figure: 12a - groove; 7 - fastening bolt; 11b - right-angled groove; 11c - right-angled block; 80 - square blank; 90 - cylindrical blank; 100 - ball valve. Detailed implementation mode

[0032] In order to enable ordinary technicians in the field to better understand the technical solution of the present invention, the technical solution of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0033] Referring to Figures 1 - 11 A forming die for a large-sized titanium alloy ball valve as shown, the forming die includes an initial shaping die for forging and shaping a non-spherical ball valve blank into a quasi-spherical shape. Among them, the non-spherical ball valve blank usually includes, for example, a square forging blank ( Figure 1 as shown) and a cylindrical forging blank ( Figure 5 as shown). These two structures are structures that are relatively easy to forge and form in forging operation techniques. Therefore, these two blank structures are usually conventional initial blanks applied to the later processing of specific workpieces (such as the ball valve shown in this application). Therefore, through the initial shaping die of the present application, the existing conventional square and cylindrical blanks are initially shaped. Since the final product of the present application is a ball valve with a spherical structure having a middle through diameter, the initial shaping die first shapes these two blank structures into a quasi-spherical structure to approximate the spherical structure of the final ball valve.

[0034] On the basis of the above-mentioned shaping of the square or cylindrical blank to approximate the quasi-spherical structure of the ball valve, in order to further shape it into a ball valve structure, the forming die further includes a final forging and shaping die for forging and shaping the quasi-spherical ball valve blank into a regular spherical shape, which can further shape the blank initially shaped into a quasi-spherical shape into a regular ball valve structure with accuracy meeting the requirements.

[0035] Therefore, in the present application, the initial shaping die and the final forging and shaping die are used to form a ball valve from blank structures different from the ball valve (square and cylindrical) by forging and shaping. Compared with the current turning processing, it can greatly improve the processing speed, save the cost of processing tools, and at the same time greatly save the blank material.

[0036] Since the square blank is forged into a cylindrical blank in the middle, this embodiment will be described by forging the square blank, and the cylindrical blank synchronizes the subsequent forging operations after forging the square blank into a cylindrical blank. Therefore, the non-spherical ball valve blank is defined as a square structure (such as Figure 1 as shown), specifically, such as Figures 2 - 4As shown, the initial shaping die includes an upper die 11 and a lower die 12. Generally, the lower die 12 is fixed on the base of the forging press (not shown in the figure), while the upper die 11 is assembled on the hydraulic rod of the forging press and corresponds to the lower die 12 vertically. Driven by the downward pressure of the hydraulic rod, the upper die 11 moves downward close to the lower die 12, and the workpiece is placed between the two to achieve the forging operation.

[0037] For the forging operation of square blanks, such as Figures 2 - 4 As shown, a positioning mechanism is provided on the lower die 12 to drive the square-structured ball valve blank to a position where each of its side lines corresponds vertically to the upper die 11. The function of this positioning structure is that since the square blank has side lines, when forging it into a spherical-like structure, the side lines need to be deformed by forging so that it gradually approaches the spherical-like structure. Therefore, through this positioning structure, the square blank can be positioned and placed at the position as shown in Figure 2 , 4 As shown, so that one of its side lines corresponds vertically to the upper die 11. A cylindrical arc surface 11a is provided on the bottom surface of the upper die 11. Then, through the downward forging action of the upper die 11, each side line part of the square blank is forged into an arc structure, so that the square blank is finally formed into a cylindrical structure.

[0038] Specifically, as shown in Figures 2 - 4 As shown, the positioning mechanism is a wedge block 4 that is symmetrically and slidably arranged on the lower die 12 and fits against the side wall of the square-structured ball valve blank (a groove for the wedge block 4 to slide and embed is provided on the lower die 12). Preferably, the wedge block 4 is adjusted and fixed by contact through a fastening bolt passing through the side wall of the lower die 11. After the wedge blocks 4 on both sides are slid and adjusted to be in flat contact with the side wall surfaces of the square blank, and locked by the fastening bolts, the single side line of the square blank corresponds vertically to the cylindrical arc surface 11a of the upper die 11. As shown in the forging flow chart in Figure 4 As shown, the square blank is successively flipped so that each of its side lines corresponds vertically to the upper die 11, and positioning is achieved through the wedge block 4. Then, the square blank can be forged into a blank with a cylindrical structure.

[0039] Since during the forging process of each side line of the square blank by the upper die 11, when the cylindrical arc surface 11a of the upper die 11 contacts the side line (right-angle structure) of the square blank, if the side line is skewed, it will cause the forging rotation of the square blank under the large forging pressure of the upper die, especially in the forging process Figure 4In step a, the other three side edges of the square blank are forged into arc structures. When forging the last side edge, since the side walls in contact with the two side wedge blocks are both arc surfaces, it is very easy to cause the left - right deflection of the square blank at the lower end, so effective side - edge forging cannot be achieved. Therefore, to solve this problem, preferably, a right - angled groove and a right - angled block for closing it are also divided on the cylindrical arc surface 11a (preferably, the right - angled block can be embedded and fixed in the right - angled groove by bolts to form a complete cylindrical arc surface 11a). When performing side - edge forging, the right - angled block can be removed. During forging, first, the side edge of the square blank is embedded into the right - angled groove, thereby limiting the left - right deflection of the square blank, and effective forging operations can be achieved. After the forging operation is completed, since a protrusion in the structure of the right - angled groove will be formed on the surface of the square blank, after the right - angled block is assembled again, the protrusion can be forged and eliminated.

[0040] After forging the square blank into a cylindrical blank as described above, and the directly selected cylindrical blanks are all continuously forged through the initial shaping die. Specifically, as Figures 6 - 7 shown, the initial shaping die further includes a second upper die 21 and a second lower die 22, and shaping arc spherical surfaces 2a are provided on both the upper and lower surfaces of the two. The cylindrical blank is placed in the shaping arc spherical surface 2a of the second lower die 22. Through the downward forging of the second upper die 21 and the shaping of the upper and lower shaping arc spherical surfaces 2a, the cylindrical blank can be formed into a blank with a spherical - like structure. In the actual forging process, through the continuous flipping of the cylindrical blank by an external mechanical fixture, it can be forged into a spherical - like structure along the circumferential direction.

[0041] After forging the cylindrical blank into a blank with a spherical - like structure as described above, the final forging and shaping die can be further used to form a ball valve product with higher precision. Specifically, as Figure 9 shown, the final forging and shaping die includes a third upper die 31, and a forming arc spherical surface 31a is provided on its lower surface. It also includes a support frame 5, and a through - diameter forming rod 6 passing through the ball valve is horizontally rotatably supported on the support frame 5. Before final forging, first, a punching operation is performed on the spherical - like blank, and the inner diameter of the punching is smaller than the through - diameter of the formed ball valve. Then, the spherical - like blank is sleeved on the through - diameter forming rod 6, and the through - diameter forming rod 6 is supported on the support frame 5 (as Figure 10 shown). By clamping the through - diameter forming rod 6 with an external mechanical fixture and rotating it, and driving the spherical - like blank to rotate (preferably, rotating a certain angle each time so that the forging action surface of the forming arc spherical surface 31a of the third upper die 31 can be connected), through multiple downward forging of the third upper die 31, the spherical - like blank is gradually shaped through the forming of the forming arc spherical surface 31a, and the wall thickness of the spherical - like blank is extruded by the third upper die 31 and the through - diameter forming rod 6 (as Figure 11As shown in the schematic diagram), the inner diameter of the ball valve reaches the size (the above punching size is smaller than the inner diameter forming size of the ball valve), and the ball valve product can be formed. Among them, since the formed arc spherical surface 31a and the ball valve product have the same radius, during forging, after the spherical blank forging completely fills the formed arc spherical surface 31a, the forging size of the ball valve product can be guaranteed. Later, through turning processing of the surface oxide skin and the through-hole diameter, a ball valve product with higher precision can be formed.

[0042] The forming method for finally forming a ball valve finished product from a square blank using the above-mentioned multiple different molds includes the following steps:

[0043] S1. Place the square blank on the first lower die 12. After the two-sided wedge blocks 4 slide close to and fit the side wall surface of the square blank, lock the wedge blocks 4 through the fastening bolts to keep the square blank fixed. At the same time, make one side line of it correspond to the cylindrical arc surface 11a of the first lower die 12 (preferably, the right-angle block can be disassembled and correspond to the right-angle groove). As Figure 2 、 4 shown, through the downward forging action of the first upper die 11, the side line of the square blank can be embedded into the right-angle groove, which can avoid the left-right skew of the square blank during downward forging, and thus can effectively realize the downward forging operation of the side line.

[0044] S2. As Figure 4 shown in the forging flow chart, successively turn the square blank so that each of its side lines corresponds vertically to the first upper die 11, and realize positioning through the wedge blocks 4. Then, the square blank can be forged into a cylindrical blank. After the forging operation is completed, since a right-angle groove structure bulge will be formed on the surface of the square blank, after assembling the right-angle block again, the bulge can be forged and eliminated.

[0045] S3. Place the cylindrical blank in the shaping arc spherical surface 2a of the second lower die 22. Through the downward forging of the second upper die 21 and the shaping of the upper and lower shaping arc spherical surfaces 2a, the cylindrical blank can be formed into a semi-spherical structure blank. During the actual forging process, through continuous turning of the cylindrical blank by an external mechanical fixture, it can be forged into a semi-spherical structure along the circumferential direction.

[0046] S4. Punch a through-hole in the middle of the semi-spherical structure blank, and the through-hole diameter is smaller than the through-hole diameter of the formed ball valve.

[0047] S5. Sleeve the semi-spherical blank on the through-hole forming rod 6, and support the through-hole forming rod 6 on the support frame 5 (as Figures 9 - 10As shown in the figure, the through-diameter forming rod 6 is clamped by an external mechanical fixture and rotated, driving the spherical blank to rotate (preferably rotating a certain angle each time so that the forging action surfaces of the forming arc spherical surfaces 31a of the third upper die 31 can be connected). Through multiple downward forging of the third upper die 31, the spherical blank is gradually shaped through the shaping of the forming arc spherical surface 31a and the extrusion of the wall thickness of the spherical blank by the third upper die 31 and the through-diameter forming rod 6 (such as Figure 11 shown), so that the inner diameter of the ball valve reaches the size, and the ball valve product can be formed. Among them, since the forming arc spherical surface 31a and the ball valve product have the same radius, during forging, after the spherical blank completely fills the forming arc spherical surface 31a during forging, the forging size of the ball valve product can be guaranteed. Later, through turning processing of the surface oxide skin and the through-diameter, a ball valve product with higher precision can be formed.

[0048] The comparison of the materials used for forging a square blank into a ball valve product by this application and currently turning a cylindrical blank into a ball valve is shown in Table 1 below:

[0049]

[0050] Table 1

[0051] For example, in item 1, the single-piece net weight of the finished ball valve is 35.72 kg. The weight of the square blank required for the processing method of this application is 75 kg, while the weight of the cylindrical blank for current turning processing is 95 kg. Therefore, it is calculated that the weight of the blank that can be saved by using the forming method of this application is (95 - 75) / 95 = 21%. Similarly, it is calculated that the material savings for items 2 - 5 are 21.4%, 25%, 30%, and 31.7% in turn. Under the comparison of this table, the mold used to form the ball valve in this application can save more than 20% of the raw materials compared with the current turning processing in the publicly announced ball valve specifications, and as the ball valve specification increases, the proportion of the saved raw materials further increases. And turning processing also includes aspects such as an increase in processing time, tool wear, and an increase in labor costs. Therefore, through the forming mold of this application for the processing and forming of large-specification ball valve products, the raw material cost and processing cost can be greatly saved. When the ball valve is processed in batches, the increase in the current turning processing cost will be further highlighted compared with this application.

[0052] The principle of the present invention is as follows: First, a blank with a square structure is placed on the first lower die 12. After the two-sided wedge blocks 4 slide close to and fit against the side wall surfaces of the square blank, the wedge blocks 4 are locked by fastening bolts to keep the square blank fixed. At the same time, one side line of the square blank corresponds to the cylindrical arc surface 11a of the first lower die 12. Through the downward forging action of the first upper die 11, the side line of the square blank can be embedded into the right-angle groove, and the single side line can be forged into an arc structure. Then, the square blank is successively flipped so that each of its side lines corresponds vertically to the first upper die 11, and positioning is achieved through the wedge blocks 4. Thus, the square blank can be forged into a blank with a cylindrical structure.

[0053] Then, the cylindrical blank is placed in the shaping arc spherical surface 2a of the second lower die 22. Through the downward forging of the second upper die 21 and the shaping of the upper and lower shaping arc spherical surfaces 2a, the cylindrical blank can be formed into a blank with a spherical-like structure. Then, a through-hole is punched in the middle of the spherical-like structure blank, and the diameter of the through-hole is smaller than the diameter of the formed ball valve. After punching, the spherical-like blank is sleeved on the through-hole forming rod 6, and the through-hole forming rod 6 is supported on the support frame 5. The through-hole forming rod 6 is clamped by an external mechanical fixture and rotated, driving the spherical-like blank to rotate. Through the multiple downward forging of the third upper die 31, the spherical-like blank is gradually shaped by the shaping arc spherical surface 31a, and the wall thickness of the spherical-like blank is extruded by the third upper die 31 and the through-hole forming rod 6, so that the inner diameter of the ball valve reaches the size, and the ball valve product can be formed.

[0054] The above shows and describes the basic principle, main features and advantages of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. A forming die for a large-sized titanium alloy ball valve, characterized in that: The forming die includes an initial shaping die for forging and shaping a non-spherical ball valve blank into a quasi-spherical shape, and a final forging and shaping die for forging and shaping the quasi-spherical ball valve blank into a regular spherical shape; The non-spherical ball valve blank has a square structure. The initial shaping die includes a first upper die (11) and a first lower die (12). A positioning mechanism is provided on the first lower die (12) to drive the square-structured ball valve blank so that its respective side edges are vertically corresponding to the first upper die (11). A cylindrical arc surface (11a) is provided on the bottom surface of the first upper die (11); A right-angle groove (11b) and a right-angle block (11c) for closing it are further divided on the cylindrical arc surface (11a); when forging the side edges of the square blank, the right-angle block (11c) is removed; after the forging of the side edges of the square blank is completed, the right-angle block (11c) is assembled in the right-angle groove (11b); The positioning mechanism is a wedge block (4) that is symmetrically and slidably arranged on the first lower die (12) and fits against the side wall of the square-structured ball valve blank.

2. The molding die according to claim 1, wherein: The initial shaping die further includes a second upper die (21) and a second lower die (22), and shaping arc spherical surfaces (2a) are provided on both their upper and lower surfaces.

3. The molding die according to claim 2, characterized in that: The final forging and shaping die includes a third upper die (31) with a forming arc spherical surface (31a) provided on its lower surface, and further includes a support frame (5). A through-diameter forming rod (6) passing through the ball valve is horizontally rotatably supported on the support frame (5).

4. The forming method of a forming die for a large-sized titanium alloy ball valve according to claim 3, characterized in that, It includes the following steps: S1. Place the square-structured blank on the first lower die (12) and fix it through the wedge block (4), and keep the side edges of the blank vertically corresponding to the first upper die (11). The first lower die (12) presses down to forge the side edge part into a quasi-arc structure; S2. Rotate and adjust the position of the square blank, and forge each side edge into a quasi-arc structure to obtain a quasi-spherical blank; S3. Place the quasi-spherical blank in the shaping arc spherical surface (2a) of the second lower die (22), and jointly shape it into a spherical-structured blank through the second upper die (21); S4. Punch a hole to punch a through-diameter hole in the middle of the spherical-structured blank; S5. Sleeve the punched spherical-structured blank on the through-diameter forming rod (6) and suspend it on the support frame (5), and finally forge a regular ball valve through the rotational cooperation of the third upper die (31) and the through-diameter forming rod (6).

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