WO2013143371A1

WO2013143371A1 - T-bend extrusion shaping method

Info

Publication number: WO2013143371A1
Application number: PCT/CN2013/071966
Authority: WO
Inventors: 李镇南
Original assignee: Li Zhennan
Priority date: 2012-03-29
Filing date: 2013-02-28
Publication date: 2013-10-03
Also published as: CN102658321A

Abstract

Disclosed is a T-bend extrusion shaping method, wherein a T-bend workpiece is clamped in a main pipe cavity formed of an upper and lower mould, and a support cylinder (14) pushes a support bar (24) in a T-bend branch pipe cavity (23) towards the pipe wall of the branch pipe opening end of the T-bend workpiece; a side cylinder (13) pushes to insert a thimble (131) into the main pipe opening, and a water injection system injects water at normal pressure into the T-bend workpiece via a liquid-through pipe cavity; the thimble (131) is continuously inserted into the main pipe inner cavity of the T-bend workpiece, the water injection system injects high pressure water into the T-bend workpiece, the copper T-bend main pipe is slightly expanded under the pressure of the water, the side cylinder (13) continues to push forward, propelling the thimble bench to extrude in the direction of the T-bend, thus together with the high pressure water in the T-bend workpiece, forcing the copper of the T-bend main pipe to extend towards the branch pipe cavity (23), and the support bar (24) in the support cavity (23) withdraws until the branch pipe is formed; the water injection system stops injecting high pressure water, the thimble (131) withdraws, the top mould (11) withdraws, and the branch pipe shaping is completed. With the aforementioned method, a higher shaping quality of T-bend shaped products can be achieved, the consistency of the shaped products is excellent and production capacity is improved.

Description

Three-way extrusion forming method

Technical field

The present invention relates to the field of metal pipe processing, and more particularly to a three-way extrusion forming process. Background technique

The tee is a pipe connection. Also known as pipe tee, tee pipe fittings or tee fittings, three general purpose in the main pipe branch, wide use, wide industry, wide application range. In the field of refrigeration, the common three-way copper is made. The traditional copper tee is mainly made by filling the lead. The copper tube is cut to a certain length, and the molten lead is poured into the inner cavity of the copper tube. After the tube cavity is solidified, the lead adhered to the surface of the copper tube and the lead of the copper tube nozzle are removed, a small hole is drilled in the port extruded from the copper tube, and then the lead in the to-be-processed part in the mold is passed through the hydraulic machine. Pressure is applied to extrude the copper tube into a copper tube tee. After the three-way forming, it is necessary to heat the lead in the tee. If the shape of the tee is Y-type or other shaped tee, the molten lead should be poured into the inner cavity of the copper tube again, and the lead is in the copper tube. After the cavity is solidified, the extruded semi-finished product is bent into a desired shape by a punching machine, the remaining amount of the product is cut and removed, and the lead in the product is melted by heating, and the product is immersed in the acid solution to remove the adhesion to the copper pipe. The lead in the inner chamber is cleaned with water after removal of lead. In order to prevent the product from rebounding, it is necessary to use a press or other equipment to shape it. Use the drill pipe to flatten the three nozzles of the tee and then pickle, dry, inspect, and package. In the process of processing lead in the process of filling lead, it is easy to cause contact between human body and lead. Lead can cause serious harm to the human body. It is mainly ingested into the body through the respiratory tract and digestive tract. Once the lead enters the human body, even through drug treatment. It is also difficult to discharge. Lead compounds can enter the human body through the lungs, digestive organs, skin, etc., and gradually accumulate in the human body. It can hinder the growth and development of red blood cells, destroy the central nervous system of people, and cause mental decline. On the other hand, lead is a non-renewable resource, and the price is increasing, which increases the manufacturing cost of the three links. Furthermore, in 2005, the United States and Japan and other countries have issued restrictions on industrial lead, stipulating that no lead should be added during the processing, so that the processing industry of the three links will be transferred to developing countries such as China, resulting in more Lead pollution incident.

In order to solve this problem, the applicant applied for an invention patent of the three-way forming die and the three-way forming method on December 21, 2010, and provided a branch pipe cavity and a support rod in the forming die, through high-pressure water. The wall of the tee workpiece is extruded to form a tee branch in the tee branch lumen. However, when water is used as the extrusion medium, the pressure of the water is increased by the thickness of the workpiece. If the thinness is inconsistent, and the water pressure needs to be high, otherwise there will be a situation in which the product cannot be inflated and the waste product is produced, and the processing qualification rate is not high.

Summary of the invention

The technical problem to be solved by the present invention is to provide a three-way extrusion forming method with good processing consistency, high qualification rate, good quality and uniform pipe wall in view of the above-mentioned deficiencies of the prior art, so that the finished product has a beautiful appearance and an inner diameter. Uniform and consistent product consistency.

The technical solution adopted by the present invention is a three-way forming method, which comprises an upper mold and a master cylinder for driving the upper mold, a lower mold, a side cylinder and a thimble, a support cylinder and a support rod, and a passage through the ejector pin. a water injection system for injecting water into the three-way workpiece, and a main cavity of the three-way workpiece is clamped on the upper mold and the lower mold, and the thimble is inserted into the opening of the main chamber under the push of the side cylinder, and the thimble is provided with a thimble step, the main cavity is connected to the branch pipe cavity, and the branch pipe cavity is provided with a support rod which is reciprocally displaceable and provides a supporting force by the support cylinder, wherein the three-way forming comprises the following steps:

1) clamping the three-way workpiece in the main cavity formed by the upper and lower molds, and pushing the support rod in the three-way branch pipe cavity toward the pipe wall of the open end of the branch pipe of the three-way workpiece;

2) The side cylinder is advanced, the thimble is inserted into the main pipe, and the water injection system injects the normal pressure water into the three-way workpiece through the liquid pipe;

3) The thimble continues to be inserted into the main cavity of the three-way workpiece, and the water injection system injects high-pressure water into the three-way workpiece, the copper tee main pipe slightly rises under the action of water pressure, and the main port is pressed against the outer wall of the thimble to form a sealing state;

4) The side cylinder continues to advance, pushing the thimble step to the three-way direction, and cooperating with the high-pressure water in the three-way workpiece to force the copper material of the tee main pipe to be pushed to the branch pipe cavity. At this time, the thrust force F2 of the thimble is larger than that of the support rod. Supporting force Fl, the support rod is retracted into the branch tube in the support cavity;

5) The water injection system stops water injection, the thimble retreats, and the upper mold retracts.

The water injection system includes a booster cylinder and a liquid storage cylinder, and the booster cylinder and the piston rod of the liquid storage cylinder are coupled to each other. The branch lumen is disposed in the lower mold or the upper mold.

The branch pipe cavity is composed of a semi-circular straight groove which is symmetrically arranged in the upper die and the lower die, respectively.

In the step of extrusion forming of the three-way branch pipe, the pressure of the high-pressure water is 30 to 200 MPa. In the step of extrusion forming of the three-way branch pipe, the pressure of the high-pressure water is preferably 60~160 MPao, and the thrust of the thimble is 30t~100t. The support pressure provided by the support rod is 5~100 MPao

The force value of the support force F1 of the support rod is constant.

Compared with the prior art, the present invention has the following advantages:

1. The three-way extrusion forming apparatus of the invention makes the three-way finished product have higher appearance quality, the finished product has good consistency, the three-way U-shaped bending position transitions smoothly, and the outer diameter of the three-way can meet the requirements of equal diameter. , reducing the production process, reducing the difficulty of the production process, and improving the quality and productivity of the product.

2. The three-way extrusion forming apparatus of the invention can complete a plurality of workpieces at the same time, has high automation degree, reasonable design of the mold, can effectively reduce product scrap rate and improve production efficiency.

3. The three-way extrusion forming method of the present invention uses water as a filling medium for high-pressure extrusion, and fully satisfies the requirements of the directives that cannot be added in the production process issued by the countries such as the United States and Japan, thereby eliminating lead pollution. Effectively reduce the damage of lead to the worker's body, make the working environment cleaner, and the water cost is lower than lead, and can be recycled to achieve environmental protection.

4. The liquid storage cylinder connected to the booster cylinder of the present invention adopts the method of first adding normal pressure water and refilling high pressure water, and the atmospheric pressure water first evacuates the air in the inner cavity of the three-way workpiece, and the high pressure water can be fully filled and lubricated. The cavity, more importantly, during the extrusion molding process of the branch pipe, the wall of the three-way workpiece tends to be uniform due to the pressure, and the main port and the thimble are sealed, when the thimble presses the three-way workpiece, The auxiliary thimble forms the branch pipe. The processing equipment used in the invention adopts liquid extrusion molding at normal temperature, and has simple structure, can efficiently and quickly produce copper tee, and is an ideal molding equipment.

DRAWINGS

Figure 1 is a schematic block diagram of a three-way extrusion forming apparatus used in the present invention;

Figure 2 is a schematic view showing the structure of a lower die of the three-way extrusion forming apparatus shown in Figure 1;

Figure 3 is a schematic view showing the structure of the ejector pin of the three-way extrusion forming apparatus shown in Figure 1;

Figure 4 is a schematic view showing the structure of the upper mold of the Y-shaped tee;

Figure 5 is a schematic view showing the structure of a lower die of a T-shaped tee;

Figure 6 is a cross-sectional view showing the structure of a support rod of a T-shaped tee;

Figure 7 is a step-by-step illustration of the thimble working state.

detailed description

The invention will be further described below by way of specific embodiments with reference to the accompanying drawings.

The three-way extrusion forming apparatus of the present invention is composed of an upper mold 11 and a lower mold 12. See Figure 1-4, tee forming The apparatus also includes a hydraulic machine 10, a side cylinder 13, a thimble 131, a support cylinder 14, and a control system. The upper mold 11 is installed in the upper cylinder of the hydraulic machine 10 and is controlled to travel up and down in the vertical direction by the control system. The lower mold 12 is placed on the hydraulic machine platform. The support cylinder 14 is a cylinder, which provides a constant thrust Fl of the support rod, and the role of the ejector pin 131. The two main ports of the workpiece clamped and fixed by the upper and lower molds are completely sealed, and a liquid filling process is performed to extrude the three-way workpiece to form the workpiece into a tee. The thimble is an elongated metal rod which is hollowed to form a liquid passage lumen 131, and the end is provided with a thimble boss for pressing the tee. The upper and lower molds are respectively symmetrically arranged with U-shaped grooves. When the upper and lower molds are closed, the upper and lower molds are enclosed by a cavity for accommodating the three-way pipe fittings, and the cavity is adapted to the shape of the three-way pipe fittings. It is more suitable when the gap between the two is 0.01~0.03mm, which is convenient for placing the U-shaped three-way pipe fittings and extracting the finished tee.

2 is a schematic view showing the structure of a lower die of the three-way extrusion forming apparatus of the present invention. The lower mold 12 of the three-way forming apparatus is provided with a U-shaped groove 120, and the U-shaped groove 120 is a semi-circular groove, and is combined with the U-shaped groove of the upper mold to form a U-shaped cavity having a circular cross section. The lower mold is provided with a three-way branch pipe cavity 140 communicating with the U-shaped groove 120. The support rod ₁₄₁ moves up and down in the three-way branch pipe cavity 140, and the movement of the support rod is driven by the power unit. The power unit is usually hydraulically operated (not shown). When processing the tee, the upper and lower molds are closed, and the thimble 131 is inserted into the main pipe of the tee pipe in the U-shaped cavity of the upper and lower molds, the water injection system works, and the liquid water enters the tee pipe from the water injection cavity in the thimble, the thimble The structure is shown in Figure 3.

Referring to Fig. 5-6, it is a schematic diagram of a T-die lower mold structure and a mounting structure of the support rod. The lower mold 21 is provided with a main chamber 22 and a branch chamber 23, as can be clearly seen from Fig. 6, the support rod 24 In the branch lumen 23. The support rod is very important for the forming of the branch pipe. It is pushed and pushed in the three-way to prevent the high-pressure water in the tee from breaking through the branch pipe. The constant force F1 of the support rod can ensure the forming quality of the branch pipe. Fig. 7 shows the process of forming the three-way branch pipe from the four position states of the thimble, wherein the position state 31 indicates that the thimble is inserted into the main nozzle (only one thimble is shown in the figure, and the other thimble is omitted). Position status 32 indicates the start of injection of high pressure water. The position state 33 indicates that the ejector step abuts against the tee main port. The position state 34 indicates a state in which the ejector pin is pressed toward the branch pipe to cause the branch pipe to be formed.

The process of three-way forming is as follows:

1) Close the mold. The upper mold moves downward and closes with the lower mold, and the three-way workpiece is clamped in the cavity formed by the U-shaped groove of the upper and lower molds. The master cylinder also provides a clamping force to the upper die to hold the upper die and the lower die in place. When the workpiece is placed in a cavity formed by the upper mold and the lower mold, the state of the support rod is at the set position and the end of the support rod abuts against the wall of the three-way workpiece. The support cylinder 14 outputs a support force F1 to push the support rod up to the lower mold U Type groove bottom.

2) The side cylinder is propelled, and the thimble is inserted into the main pipe. The water injection system injects the normal pressure water into the three-way workpiece through the liquid pipe cavity. The filling of the squeezing medium is completed and the air in the tee workpiece is emptied.

3) The thimble continues to be inserted into the main lumen of the three-way workpiece. When in the set position, the boosting cylinder of the water injection system works, the liquid storage cylinder of the water injection system communicates with the liquid passage lumen of the thimble, and the water is pressurized by the booster cylinder. From the liquid passage tube of the thimble into the three-way inner cavity, the water pressure in the copper tee is simultaneously increased, the copper tee main pipe slightly rises under the action of water pressure, and the main port is pressed to form a seal on the outer wall of the thimble. The pressure of the high pressure water after the thimble is inserted into the tee main pipe to support the boosting cylinder is in the range of 30 to 200 MPa. It is preferably 60 to 160 MPa.

4) The side cylinder continues to advance, pushing the ejector step against the three-way main port, and continuing to press in the direction of the three-way branch end, and cooperating with the high-pressure water in the three-way workpiece to force the copper material of the tee main pipe to the branch cavity At this time, the supporting cylinder transmits a supporting force F1 for which the force value is kept constant to the supporting rod, the thrust force F2 of the thimble is larger than the supporting force F1 of the supporting rod, and the supporting rod is retracted into the branch tube forming in the supporting cavity. In this step, the thrust of the thimble is 30t~100t (t means the unit of weight per ton). The support pressure provided by the support rod is 5~100 MPa. During this process, the thimble acts as a seal and support.

5) The booster cylinder stops working. The water injection system injects the normal pressure water into the tee, the side cylinder depressurizes the ejector pin, and the upper die rises to take out the workpiece.

For different shapes of tees, the process procedure in the clamping stage will be slightly different, such as T-pass. In the mold-closing step, the straight-tube three-way workpiece is placed in the semi-circular groove of the cavity, and the support cylinder works. The support rod is placed on the pipe wall of the workpiece, and the upper mold is pressed down to the lower mold to hold the pressure, and then the side cylinder is pushed into the normal pressure water. For Y-pass, the U-shaped three-way workpiece is first placed in a U-shaped semi-circular groove, the main cylinder is downwardly locked and held, and the rear support cylinder pushes the support rod to the support rod against the opening of the three-way branch pipe. On the wall of the pipe. The side cylinders are advanced and the thimbles are inserted into the two main ports.

When the three-way branch pipe (T-pass) is formed, the booster cylinder is reset, the workpiece is not filled with high-pressure water, but the normal-pressure water, the side-cylinder retreats, the thimble is retracted from the main pipe, and the master cylinder drives the upper die upward. At this time, it is operated by the supporting cylinder, and the releasing force is outputted to the support rod, so that the formed tee is withdrawn from the branch pipe cavity. Among them, the demolding force is larger than the constant support force F1.

For the Y-pass, in this step, since the branch pipe cavity is formed by the two semi-circular grooves on the upper die and the lower die, when the booster cylinder is retracted, the upper die is advanced, and the side cylinder is retracted. The workpiece can be removed. At this time, the support cylinder does not need to work to push out the tee workpiece. During the extrusion molding of the three-way branch pipe, the support force of the support rod is provided by the support cylinder and the force value is constant. If the support force of the support rod is provided by the spring or the superior glue, the support force will generally increase gradually with the compression of the spring or the deformation of the superior glue, which is not conducive to the formation of the branch pipe, and the present invention provides a support cylinder. The constant support force can improve the forming quality of the three-way branch pipe, and the thickness of the inner wall of the branch pipe is uniform.

The three-way extrusion forming of the invention adopts water as the medium for extrusion forming, and has great social and economic benefits. Compared with the method of using lead forming or oil forming, the invention has obvious technical advantages, and the forming of the three-way branch pipe By adjusting the working hydraulic pressure on both sides of the support rod by the system, the extrusion length of the branch pipe can be changed, so that the adaptability of the mold is wider. A water tank can be arranged under the lower mold of the hydraulic machine. When the workpiece is processed, the water in the workpiece flows into the water tank, returns to the hydraulic system for recycling, is environmentally friendly and keeps the working environment clean.

Claims

Claim

A three-way extrusion forming method, the three-way forming apparatus comprising an upper mold and a master cylinder for driving the upper mold, a lower mold, a side cylinder and a thimble, a support cylinder and a support rod, and a liquid passage cavity through the thimble a water injection system for injecting water into the three-way workpiece, a main cavity of the three-way workpiece is clamped on the upper mold and the lower mold, and the thimble is inserted into the opening of the main chamber under the pushing of the side cylinder, and the thimble is provided with a thimble step. The main cavity communicates with the branch pipe cavity, and the branch pipe cavity is provided with a reciprocable displacement support rod supported by the support cylinder, wherein the three-way forming comprises the following steps:

2) pushing the side cylinder, inserting the thimble into the main pipe, and the water injection system injects the normal pressure water into the three-way workpiece through the liquid pipe;

3) The thimble continues to be inserted into the inner cavity of the three-way workpiece, and the water injection system injects high-pressure water into the three-way workpiece, the copper tee main pipe slightly rises under the action of water pressure, and the main port is pressed against the outer wall of the thimble to form a sealing state;

5) The water injection system stops the injection of high pressure water, the thimble retreats, the upper die retreats, and the branch pipe is formed.

The three-way extrusion forming method according to claim 1, wherein the water injection system comprises a booster cylinder and a liquid storage cylinder, and the booster cylinder and the piston rod of the liquid storage cylinder are coupled to each other.

The three-way extrusion forming method according to claim 2, wherein the branch pipe cavity is disposed in the lower die or the upper die.

A three-way extrusion forming method according to claim 2, wherein: said branch pipe cavity is constituted by a semi-circular straight groove mold which is symmetrically disposed in the upper mold and the lower mold, respectively.

The three-way extrusion forming method according to claim 4, wherein in the step of extruding the three-way branch pipe, the pressure of the high-pressure water is 30 to 200 MPa.

The three-way extrusion forming method according to claim 5, wherein in the step of extruding the three-way branch pipe, the pressure of the high-pressure water is preferably 60 to 160 MPao.

7. The three-way extrusion forming method according to claim 5, wherein: the thrust of the thimble is 30t~100t.

The three-way extrusion forming method according to claim 5, wherein the support rod provides a supporting pressure of 5 to 100 MPao.

The three-way extrusion forming method according to claim 1, wherein the force value of the supporting force F1 of the support rod is constant.