CN109277461B - integral extrusion forming die for complex inner ring rib of light alloy shell - Google Patents

Abstract

The present invention discloses an integral extrusion mold for complex inner ring ribs of a light alloy shell, which includes an upper mold assembly, an inner support structure assembly and a lower mold assembly, the lower mold assembly includes a die for accommodating a light alloy cylindrical piece, The upper mold assembly includes a punch for extruding light alloy cylindrical parts downwards, and the inner support structure assembly includes an upper inner support and a lower flexible filling inner support; the lower flexible inner inner support is made of flexible material according to the shape of the lower part of the inner ring rib. For the sand mold required for the ring bar, the lower flexible filling body support is placed at the lower part of the inner ring bar, the upper inner support forms the shape of the upper part of the inner ring bar, and the upper inner support is placed at the upper part of the inner ring bar. The invention greatly improves the utilization rate of materials, overcomes the difficult problems brought about by using the support structure material in the split petals for precision plastic forming, and solves the jamming problem when the mold is released, thereby protecting the mold and realizing large-scale, complex and lightweight Simultaneous forming of inner ring ribs during overall plastic forming of alloy shell components.

Description

Integral Extrusion Die for Complicated Inner Ring Rib of Light Alloy Shell

technical field

The invention relates to the technical field of plastic processing and forming of metal materials, in particular to an extrusion forming die for the inner ring rib of a large complex light alloy shell.

Background technique

With the development of aerospace technology, the integration of large and complex light alloy shell components is becoming more and more intense. However, there are certain difficulties in the development of key complex shell components, which are manifested in: high development cost, long cycle, low forming dimensional accuracy, mainly relying on machining to ensure accuracy; large and complex light alloy shells are prone to defects during the forming process, Large fluctuations in performance and unstable quality lead to low reliability and pass rate. The precise forming technology of key complex shell components in some advanced weaponry has not yet been broken through in China, and many key complex shell components in new weaponry have to rely on imports or decompose them into several parts. It can be seen that forming technology plays a vital role in the development of my country's advanced weapons and equipment and the development of the national defense industry. Among them, the performance of parts produced by metal plastic forming method is the best. It is the general trend that metal plastic forming technology is applied to the production of military products. The production of large and complex light alloy shell components with inner ring ribs is an indispensable part of the development of national defense products.

The overall forming of the inner ring rib of large and complex light alloy shell components is particularly difficult. Traditional forming methods, such as segmental forming and then welding, casting or machining, produce products with varying degrees of welding cracks, casting bubbles, Defects and deficiencies such as shrinkage cavities, high processing costs, and waste of resources not only have low performance but also cannot meet the service requirements of the product. An improved method - using the hot extrusion forming method of the split inner support structure to realize the precision plastic forming of the inner ring rib of the large complex light alloy shell member, as shown in Figure 1-2a. The inner ring rib is formed on the basis of the light alloy cylindrical part as shown in Figure 4 formed by the first step of reverse extrusion, and the second extrusion is formed into a large complex light alloy shell with an inner ring rib as shown in Figure 5 Body components.

Although the utilization rate of materials can be improved to a certain extent, there are still some processing difficulties and disadvantages. If the inter-engaged split-valve internal support mold structure is adopted, the structural characteristics of the split-lobe mold will form a certain gap between the petals after they are separated. During hot extrusion, part of the metal will flow into the gap of the split mold, forming burrs, resulting in the loss of part of the material and the jamming problem when the mold is released. At the same time, the processing and assembly requirements of the support structure mold in the split petal are relatively high, and it is difficult to realize it accurately, as shown in Figure 2-2a.

The difficulty in forming this type of part is that the lower support of the inner ring rib needs the inner support to realize the enlargement and reduction in the diameter direction, and at the same time it is easy to place and take out the mold; the second is that the inner ring rib needs to be formed at a certain position. , it is necessary to ensure that the upper support of the inner ring rib remains stationary at a certain position and at the same time realize the plastic forming of the light alloy cylindrical part by the punch; the third is that the inner support material ensures the realization of the inner ring rib forming Basically, the inner ring rib will not be damaged when the mold is taken out.

Contents of the invention

In view of the above three problems, combined with the existing processing technology, the purpose of the present invention is to provide an integral extrusion mold for complex inner ring ribs of light alloy shells, so as to realize the precision plastic forming of inner ring ribs of large complex light alloy shell components , the mold greatly improves the utilization rate of materials, overcomes the difficulties caused by the precision plastic forming of the support structure material in the split flap, and solves the jamming problem when the mold is released, thereby protecting the mold and realizing large and complex Simultaneous forming of inner ring ribs during overall plastic forming of light alloy shell components.

In order to achieve the above object, the technical scheme of the present invention is as follows:

An integral extrusion mold for the complex inner ring rib of a light alloy shell, including an upper mold assembly connected with the upper structure of the press, an inner support structure assembly and a lower mold assembly connected with the lower structure of the press, the lower mold assembly includes The die for accommodating the light alloy cylindrical piece, the upper mold assembly includes a punch for extruding the light alloy cylindrical piece downward, and the inner support structure assembly includes a disc spring, a disc spring support rod, a wedge, an upper inner support , the mandrel and the lower part of the flexible filler are supported in the body; the upper part of the oblique wedge is tightly connected to the disc spring support rod, and the lower part of the oblique wedge is tightly connected to the mandrel; the upper inner support and the lower part of the flexible filler are supported in the body Form a closed space, the inner support of the lower part of the flexible filling follows the shape of the lower part of the inner ring bar, and the sand mold required for the inner ring bar is made of flexible materials. The shape of the upper part, the upper inner support is placed on the upper part of the inner ring rib, and the inner support of the lower flexible filling bears the pressure from the upper inner support and the mandrel, so as to provide three-dimensional compressive stress for the flexible filling body during forming, so as to ensure that the inner The forming of the ring rib is complete.

Further, the upper mold assembly also includes an upper template and an upper mold backing plate connected to the upper workbench of the press; the upper template is assembled on the upper workbench of the press with fastening bolts; the upper template, the upper mold The backing plate and punch are assembled together with hexagon socket head cap screws.

Further, the lower mold assembly also includes a lower formwork connected to the lower workbench of the press, a knockout plate, a top block and a push rod; the lower formwork is assembled on the lower workbench of the press with fastening bolts; the The lower template and the die are fixed together by hexagon socket head screws; the jack block and the ejector rod are connected together by screw fastening, and there are corresponding grooves on the die and the lower template, and the jack block Positioning function; the punching plate is a T-shaped key structure, and there is a corresponding matching T-shaped groove structure on the die.

The beneficial effects of the present invention are:

1. The flexible filler used has certain high temperature strength. The flexible filling body adopts heat-resistant molding sand with a certain high-temperature strength for casting, which can adapt to certain deformation and expansion and contraction. It has the advantages of easy discretization after forming, and easy removal from the inner cavity with ring ribs. The upper internal support and the lower flexible structure internal support jointly constitute the closed space for forming the inner ring rib. During the forming process, the flexible filling body has sufficient high temperature strength to withstand the pressure from the upper inner support and the mandrel, and the light alloy cylindrical part can be changed by controlling the process parameters (forming angle of the beading part, fillet of the transition zone) The force on the wall metal during the extrusion and deformation of the inner ring reinforcement can better control the metal stress state, equivalent variable, plastic deformation and tissue uniformity, etc., ensuring the orderly flow of the wall metal and transforming it into an inner ring. Ring ribs, the formed inner ring ribs are continuous and complete with the streamline of the shell wall metal.

2. Propose a new inner support structure that is easy to take out. As shown in Figure 3, this is a kind of flexible filling in vivo support. This kind of material can be easily processed into complex shapes of filling bodies corresponding to various inner ring bars. Compared with the internal support of the split mold structure, this kind of flexible filling internal support saves a lot of cost. It is not only suitable for the inner ring rib structure provided in the present invention, but also suitable for the overall forming of some crisscross complex inner rib structures. After the extrusion is completed, the flexible filling body is deformed and dispersed for easy removal by controlling the temperature reasonably.

3. Simplify mold design. For the split internal support structure, the design calculation is very complicated, the assembly precision is high, the assembly is difficult, and the angle and gap between the split petals are difficult to control accurately. During the extrusion process, the motion matching of each split module is difficult to meet the design requirements. During the operation, part of the metal flows into the gap of the split mold, resulting in burrs which cause the mold to jam, resulting in forming failure. In the present invention, the flexible filling body is a whole, and there is no problem of flashing during the process of forming. In addition, the use of flexible fillers as the inner support structure not only enables the integral forming of the inner ring ribs of large and complex light alloy shell components, but also avoids the cumbersome process of separately placing the support structure components in the split mold, which simplifies mold design and operation. more convenient.

4. Reduce the processing cost of the mold. Compared with the internal support structure of the split mold, the flexible filler is used as the internal support structure. One is to avoid the metal flowing into the gap of the split mold during the extrusion forming process to form flashes that cause the mold to be jammed. The problem of processing molds; the second is that for such large and complex light alloy components with inner ring ribs, the processing accuracy of the support in the split mold is high, the processing cost is expensive, and the yield is low. However, the flexible filling body is used as the inner support structure, and the upper mold component and the inner support structure component are skillfully connected together by using a tapered inclined surface structure, so that the mold structure can be regarded as two parts: the upper mold part and the lower mold part. The processing is simple and the production cost is saved.

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

Description of drawings

Fig. 1 is a sectional view of the working state of the mold when the light alloy tubular part is extruded by utilizing the support in the split mold;

Fig. 2 is the sectional view of support in split mold;

Figure 2a is a bottom view of the support in the sub-valve;

Fig. 3 is a schematic diagram of the working state of the mold when the light alloy cylindrical part is extruded by using flexible material as the inner support structure in the embodiment provided by the present invention;

Fig. 4 is the schematic diagram of light alloy tubular part in the embodiment provided by the present invention;

Fig. 5 is a schematic diagram of a large complex light alloy component with inner ring ribs formed by extruding the light alloy cylindrical part in the embodiment provided by the present invention.

Label description

1—upper template; 2—upper mold backing plate; 3—hexagon socket head cap screw; 4—punch; 5—disc spring; 6—disc spring support rod; 7—wedge; 8—upper inner support; 9 —mandrel; 10—support in the lower flexible filling body; 11—die; 12—top block; 13—enclosed space; 14—lower formwork; 15—ejector; 16—beating plate; .

Detailed ways

The present invention discloses an integral extrusion mold for complex inner ring ribs of a light alloy shell, as shown in Figures 1-4, which includes an upper mold assembly connected to the upper structure of the press, an inner support structure assembly, and an assembly connected to the press The lower mold assembly connected to the lower structure, the lower mold assembly includes the die 11 for accommodating the light alloy cylindrical piece 17, and the upper mold assembly includes the punch 4 for pressing the light alloy cylindrical piece 17 downward.

The upper mold assembly also includes an upper template 1 and an upper mold backing plate 2 connected to the upper workbench of the press. The upper template 1 is assembled on the upper workbench of the press with fastening bolts. The upper template 1 , the upper mold backing plate 2 and the punch 4 are assembled together by hexagon socket head cap screws 3 .

The internal support structure assembly includes a disc spring 5 , a disc spring support rod 6 , a wedge 7 , an upper inner support 8 , a mandrel 9 and a lower flexible filling inner support 10 . The oblique wedge 7 and the disc spring support rod 6 are connected together by screw fastening, and the oblique wedge 7 and the mandrel 9 are also connected together by screw fastening. Shape, using flexible materials to make the sand mold required by the inner ring rib, the lower flexible filling body support 10 is directly placed at the lower part of the inner ring rib, the upper inner support 8 forms the shape of the upper part of the inner ring rib, and the upper inner support 8 is placed on the inner ring rib In the upper position, the upper inner support 8 and the lower flexible filling body support 10 form a closed space 13 to provide three-dimensional compressive stress for the flexible filling body during forming, thereby ensuring the integrity of the forming of the inner ring rib. The lower mold assembly also includes a lower template 14 connected to the lower workbench of the press, a knockout plate 16, a top block 12 and a push rod 15. The lower template 14 is assembled on the lower workbench of the press with fastening bolts. The lower template 14 and the die 11 are fixed together by hexagon socket head cap screws 3 . The jack block 12 and the ejector rod 15 are connected together by screw fastening, and there are corresponding grooves on the die 11 and the lower template 14 to position the jack block 12 . The punching plate 16 is a T-shaped key structure (not shown), and a corresponding matching T-shaped groove structure (not shown) is arranged on the die 11 .

The inner ring rib is formed on the basis of the light alloy cylindrical part 17 shown in Figure 4 formed by the first step of reverse extrusion, and the second extrusion is formed into a large complex light alloy with an inner ring rib as shown in Figure 5 member. Therefore, the sequence of the inner ring rib extrusion forming method of the above components is as follows:

(1) Preparation before forming: heat the light alloy cylindrical part 17 and the mold as shown in Fig. 4 to the forming temperature and keep it warm for a certain period of time, and install it on the press according to the above assembly relationship. In addition, the surfaces of the male mold 4 , the concave mold 11 , and the inner support are evenly coated with oil-based graphite lubricant, and the light alloy cylindrical piece 17 is placed in the concave mold 11 .

(2) Forming process: firstly, the above-mentioned mold is placed in place, and the inner support 10 of the lower flexible structure is placed into the light alloy cylindrical part 17 . The press drives the upper mold plate 1, the upper mold backing plate 2 and the punch 4 of the upper mold assembly to move downward. With the pressing down of the press, the upper inner support 8 reaches the designated position and enters the extrusion forming stage.

The punch 4 moves relative to the upper inner support 8 that is running in place, and at the same time the upper die backing plate 2 starts to come into contact with the disc spring 5. The disc spring 5 can withstand a certain load deformation, and the upper inner support 8 produces The downward force of the light alloy cylindrical piece will cancel each other out against the upward force produced by the upper inner support 8 . At the same time, the disc spring 5 can play a role of sealing to meet the sealing requirements, can achieve the effect of low stroke and high compensation force, and ensure that the formed inner ring rib meets the precision requirements to the greatest extent.

(3) After extrusion molding is completed: the upper worktable of the press stops moving downward, and the upper worktable of the press moves upward in the opposite direction, driving the punch 4 to rise and make the punch 4 separate from the inner ring rib of the component, and continue to rise the punch 4 will drive the upper inner support 8 to move upward. At this time, it is necessary to laterally push the knockout plate 16 to the knockout position to ensure that the light alloy cylindrical part 17 does not move together with the upper inner support 8 . The workbench continues to move upwards, so that the light alloy cylindrical part 17 is disengaged, and the ejector rod 15 pushes out the formed member. After that, by controlling a reasonable temperature, the support in the flexible filling body is deformed and discretized, which is easy to take out, so as to complete the extrusion and obtain the required inner ring ribs of large and complex light alloy shell components.

Compared with the prior art, the present invention has the following technical effects:

1. The flexible filler used has certain high temperature strength. The upper inner support 8 and the lower flexible structure inner support 10 jointly constitute a closed space 13 for forming inner ring ribs. During the forming process, the flexible filling body has sufficient high temperature strength to withstand the pressure from the upper inner support 8 and the mandrel 9, and the light alloy cylinder can be changed by controlling the process parameters (forming angle of the beaded part, fillet of the transition zone) The force condition of the wall metal of the shaped part 17 during the extrusion deformation of the inner ring rib can better control the metal stress state, equivalent variable, plastic deformation and tissue uniformity, etc., ensuring the orderly flow of the wall metal and Transformed into an inner ring rib, the formed inner ring rib is continuous and complete with the flow line of the shell wall metal.

2. Propose a new inner support structure that is easy to take out. As shown in 10 in Figure 3, this is a kind of flexible filling in vivo support. This kind of material can be easily processed into complex shapes of filling bodies corresponding to various inner ring bars. Compared with the internal support of the split mold structure, this kind of flexible filling internal support saves a lot of cost. It is not only suitable for the inner ring rib structure provided in the present invention, but also suitable for the overall forming of some crisscross complex inner rib structures. After the extrusion is completed, the flexible filling body is deformed and dispersed for easy removal by controlling the temperature reasonably.

3. Simplify mold design. For the split internal support structure, the design calculation is very complicated, the assembly precision is high, the assembly is difficult, and the angle and gap between the split petals are difficult to control accurately. During the extrusion process, the motion matching of each split module is difficult to meet the design requirements. During the operation, part of the metal flows into the gap of the split mold, resulting in burrs which cause the mold to jam, resulting in forming failure. In the present invention, the flexible filling body is a whole, and there is no problem of flashing during the process of forming. In addition, the use of flexible fillers as the inner support structure not only enables the integral forming of the inner ring ribs of large and complex light alloy shell components, but also avoids the cumbersome process of separately placing the support structure components in the split mold, which simplifies mold design and operation. more convenient.

4. Reduce the processing cost of the mold. Compared with the internal support structure of the split mold, the flexible filler is used as the internal support structure. One is to avoid the metal flowing into the gap of the split mold during the extrusion forming process to form flashes that cause the mold to be jammed. The problem of processing molds; the second is that for such large and complex light alloy shell components with inner ring ribs, the processing accuracy of the support in the split mold is high, the processing cost is expensive, and the yield is low. However, the flexible filling body is used as the inner support structure, and the upper mold component and the inner support structure component are skillfully connected together by using a tapered inclined surface structure, so that the mold structure can be regarded as two parts: the upper mold part and the lower mold part. Simple and save production cost.

The above are only specific embodiments of the present invention, and are not intended to limit the protection scope of the present invention. All equivalent changes made according to the design idea of this case fall within the scope of protection of this case.

Claims (3)

1. The utility model provides a whole extrusion forming die of complicated inner ring muscle of light alloy casing, includes the last die assembly who is connected with the superstructure of press, interior bearing structure subassembly and the lower die assembly who is connected with press substructure, lower die assembly includes the die of holding light alloy cylinder, goes up the die assembly and includes the terrace die of extrusion light alloy cylinder down, its characterized in that: the inner support structure component comprises a disc spring, a disc spring support rod, a wedge, an upper inner support, a mandrel and a lower flexible filler inner support; the upper part of the inclined wedge is fixedly connected with the disc spring supporting rod, and the lower part of the inclined wedge is fixedly connected with the core shaft; the upper portion inner support and the lower portion flexible filling body support to form a closed space, the lower portion flexible filling body support is made of flexible materials into a sand mold required by the inner ring rib according to the shape of the lower portion of the inner ring rib, the lower portion flexible filling body support is arranged at the lower portion of the inner ring rib, the upper portion inner support forms the shape of the upper portion of the inner ring rib, the upper portion inner support is arranged at the upper portion of the inner ring rib, and the lower portion flexible filling body support bears pressure from the upper portion inner support and the mandrel.

2. The integral extrusion forming die for the complex inner annular rib of the light alloy shell as claimed in claim 1, wherein: the upper die assembly also comprises an upper die plate and an upper die base plate which are connected with an upper workbench of the press machine; the upper template is assembled on an upper workbench of the press machine by fastening bolts; the upper template, the upper die base plate and the male die are assembled together through the hexagon socket head cap screws.

3. The integral extrusion forming die for the complex inner annular rib of the light alloy shell as claimed in claim 1, wherein: the lower die assembly also comprises a lower die plate, a knockout plate, a top block and a top rod which are connected with a lower workbench of the press; the lower template is assembled on a lower workbench of the press machine by fastening bolts; the lower template and the female die are fixed together through an inner hexagonal cylindrical head screw; the ejector block and the ejector rod are connected together in a threaded fastening mode, and corresponding grooves are formed in the female die and the lower template to position the ejector block; the material beating plate is of a T-shaped key structure, and a corresponding matched T-shaped groove structure is arranged on the female die.