MXPA01000667A - Hydro compression tube forming die and method for making same - Google Patents

Abstract

An apparatus is provided for forming a tubular fitting from a blank tube having an interior. The apparatus includes a right die plate, a left die plate, a lower die plate and an upper die plate. The right die plate has a first cavity capable of receiving the blank tube. The left die plate has a second cavity aligned with the first cavity. The right die plate has a first guide post and the left die plate has a second guide post. The first cavity is joined to the second cavity to form a forming cavity. The lower die plate is capable of supporting the right die plate and the left die plate. The lower die plate includes a port capable of receiving a fluid line. The upper die plate is capable of moving between a first position and a second position. The upper die plate has guide holes for receiving the first and second guide posts and aligning the upper die plate with the right die plate and the left die plate. The apparatus further includes a fluid delivery means for communicating a fluid via the fluid line to the interior of the blank tube. A plunger is used to pressurize the fluid in the blank tube to expand the tube so that the shape of the tube conforms to the forming cavity.

Description

HYDROCOMPRESSION TUBE FORMING MACHINE AND METHOD TO MANUFACTURE THEM FIELD OF THE INVENTION The present invention relates, in general, to the field of cold rolling of tubular materials and, more particularly, to an apparatus and method for hydroforming a tubular accessory from a tubular target.

BACKGROUND OF THE INVENTION The industry requires tubular forms of one piece to be obtained from standard tubular targets. The operations of bending, stretching, crushing and radial expansion of a tubular target, with or without a mandrel, are known. From some metals and alloys, complex tubular profiles are formed through a hydroforming process. The hydroforming process requires several steps to form the desired tubular profile. See, for example, U.S. Patent Application Serial No. 08 / 856,511, filed May 15, 1997, and assigned to the assignee of the present application, which application is hereby incorporated by reference in its entirety. Generally, a tube or workpiece is placed between a pair of dies having cavities that define the desired, desired profile of the tube. The dies are joined and the ends of the work piece are sealed with a pair of sealing units. The workpiece is filled with fluid that is then pressurized. The pressurization of the fluid within the workpiece results in the expansion of the work piece to conform to the shape of the cavity. The fluid is drained from the work piece and the sealing units are removed to release the work piece. The main problem with this process is that the hydroforming presses are extremely expensive. A single press hydroformadora can cost approximately three million dollars. Since mechanical or hydraulic presses are widely available and have been in service in many factories for years, attempts have been made to modify these presses to carry out the previous hydroforming operation. The problem with previous attempts to perform hydroforming operations on mechanical or hydraulic presses is that many additional pieces of equipment are required in order to make the hydroforming operation work. This equipment may include, for example, external water units, hydraulic and additional accessories, external, hoses and valves. This increases the cost and decreases the reliability of the hydroforming operation. The present invention is focused on eliminating some of the additional equipment required to carry out a hydroforming operation.

SUMMARY OF THE INVENTION In accordance with one aspect of the present invention, there is provided an apparatus for forming a tubular fitting from a tubular target having an interior. The apparatus includes a right die plate, a left die plate, a lower die plate and an upper die plate. The right die plate has a first cavity capable of receiving the tubular target. The left die plate has a second cavity aligned with the first cavity. The right die plate has a first guide post and the left die plate has a second guide post. The first cavity is joined to the second cavity, to form a forming cavity. The lower die plate is capable of supporting the right die plate and the left die plate. The lower die plate includes a hole capable of receiving a fluid line. The upper die plate is able to move between a first position and a second position. The upper die plate has pilot holes for receiving the first and second guide posts and aligning the upper die plate with the right die plate and the left die plate. The apparatus further includes a fluid supply means for communicating a fluid, through the fluid line, to the interior of the tubular target. A piston is used to pressurize the fluid in the tubular target and expand the tube, so that the shape of the tube fits into the forming cavity.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing advantages, as well as other advantages of the invention, will become apparent upon reading the following detailed description and upon reference to the drawings, in which: Figure 1 is a side view with part separation of a die in accordance with one embodiment of the present invention; Figure 2 is a top view of one embodiment of the upper die plate of the present invention; Figure 3 is a top view of one embodiment of the right and left die plates of the present invention; Figure 4 is a top view of one embodiment of the lower die plate of the present invention; and Figure 5 is a cross-sectional view of the right die plate of Figure 3, along line 5-5. Although the invention is susceptible to various modifications and alternative forms, specific embodiments have been presented by way of example in the drawings and will be described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms described. On the contrary, the invention will cover all modifications, equivalents and alternatives that fall within the spirit and scope of the invention, as defined by the appended claims.

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a hydraulic press operates as a hydroformer apparatus. The hydroforming device creates a tubular accessory from a tubular target. In one embodiment, the punching apparatus for hydrocompression tube forming is used in a hydraulic press. The hydraulic press includes a moving press part. The hydraulic press implements a hydroforming process that gives form to the tubular target to produce a generally tubular profile. The process of hydroforming requires that the tubular target be enclosed in a forming cavity between the die plates, right and left, joined together. The tubular target is filled with fluid. A piston starts in a retracted position. The piston is lowered into the interior of the tube to the depth shown, in order to pressurize the fluid and expand the tubular target into the recess of the forming cavity. In this way, a tubular accessory is formed which has a shape that molds to the forming cavity. As illustrated in Figure 1, the hydroformer apparatus used in the above process includes a die 10 having a right die plate 16 (shown in Figure 3), a left die plate 18, a lower die plate 12 and an upper die plate 14. The upper die plate 14 is mounted to a moving part of the press. The lower die plate 12 is mounted to a fixed die platform, through the bolt holes 50 (shown in Figure 4). Referring to Figure 5, a tubular fitting is formed by placing the tubular blank, with the open end upward, on a tube setter 24 contained in a first cavity 22 in the right die plate 16. The right die plate 18 includes a second cavity. The first cavity 22 is aligned with the second cavity to form a forming cavity 26. The forming cavity 26 represents the desired cross-sectional shape of the tube formed. The lower die plate 12 supports the right and left die plates 16 and 18. When the hydroforming process starts, the upper die plate 14 is in a first position displaced away from the upper part 28 of the right die plates. left 16 and 18. Subsequently, the moving part of the press moves the upper die plate 14 from the first position to a second position adjacent to the upper part 28, as illustrated in Figure 5. The moving part of the press moves the upper die plate 14 by means of a first moving means, such as, for example, hydraulic cylinder assemblies and motor and screw combinations. As illustrated in Figure 3, the right die plate 16 includes a first guide post 34 and the left die plate 18 includes a second guide post 36. As illustrated in Figure 2, the top die plate 14 has a first and second corresponding guide holes 38 and 40, for receiving the first guide post 34 and the second guide post 36 and aligning the upper die plate 14 with the right and left die plates 16 and 18. Then, the descent of the plate of upper die 14 presses the right and left die plates 16 and 18 into a sealed position.

Focusing on Figure 5, the right die plate 16 includes a tube setter 24, which has therein a conduit 25 capable of receiving and draining fluid. As illustrated in Figure 4, the lower die plate 12 also includes a conduit 25 which is connected to an aperture 42 which is capable of receiving a connecting member, such as for example a line for fluid, a pressure gauge, etc. A fluid supply means, such as for example a hydraulic pump, supplies fluid through the conduit 25 into the tubular target placed in the forming cavity 26, illustrated in Figure 5. The position bolts 46, 48 are partially positioned within the first die plate or right die plate 16 and partially within the second die plate or left die plate 18, as shown in Figures 3 and 5. The conduit 25 is in fluid communication with the fluid line that the fluid provides. A piston 32 is used to pressurize the fluid in the tubular target. The pressurized fluid expands the tube so that it molds into the forming cavity 26 thereby forming the tubular fitting. The fluid pressure in the tube is increased by lowering the piston 32 through a hole in the piston as shown in Figures 2 and 3 and inside the tube, to the depth shown in Figure 5. The moving part of the the press includes a second movement means for lowering the piston 32 within the fluid filled tube and thus increasing the pressure in the tube. That means of movement may include, for example, hydraulic cylinder assemblies and motor and screw combinations. The resulting pressure in the tube is high enough to expand the tube and fill the voids in the forming cavity 26. This pressure depends on the material of the tubular target and the distance D to which the piston is inserted into the tube. This pressure is greater than the pressure at the point of deformation, which would expand the tube within the recesses of the forming cavity, and less than the pressure at the point of deformation of the die plates. In normal operation, the pressure is greater than 703.07 kilograms per square centimeter (10,000 pounds per square inch). For example, the pressure can be as high as 7,030.7 kilograms per square centimeter (100,000 pounds per square inch), as long as the die plates are not separated. The typical pressure range is between 3,515.35 kilograms per square centimeter (50,000 pounds per square inch) and 7,030.7 kilograms per square centimeter (100,000 pounds per square inch). By increasing the pressure of the fluid in the tube, the tube expands into the recesses of the forming cavity 26. After the tube has expanded, the pressure on the fluid is decreased by removing the piston 32 and draining the fluid from the tube. formed, through the conduit 25 in the pipe setter 24. The upper die plate 14 is then raised to allow the formed tube to be removed from the right and left die plates 16 and 18. The formed tube can be removed with the help of elevators. Although particular embodiments and applications of the present invention have been illustrated and described, it will be understood that the invention is not limited to the precise structure and compositions described herein, and that various modifications, changes and variations will be apparent from the foregoing descriptions. , without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (16)

NOVELTY OF THE INVENTION Having described the above invention, it is considered as a novelty, and therefore, the content of the following is claimed as property: CLAIMS

1. An apparatus for forming a tubular fitting from a tubular target having an interior, the apparatus is characterized in that it comprises: a first die plate having a first cavity capable of receiving the tubular target, the first die plate having a first guide post; a second die plate having a second cavity aligned with the first cavity, the second die plate having a second guide post, the first cavity and the second cavity being configured to join and form a forming cavity; a lower die plate capable of supporting the first die plate and the second die plate, the lower die plate having an opening capable of receiving a fluid line; an upper die plate capable of moving between a first position and a second position, the upper die plate has first and second guide holes for receiving the first and second guide posts and aligning the upper die plate with the first die plate and with the second die plate; means for supplying fluid, for communicating a fluid, through the fluid line, into the interior of the tubular target; and a piston placed inside the tubular target, to pressurize the fluid that is in the tubular target and thereby expand the tube, so that it molds to the forming cavity. The apparatus according to claim 1, characterized in that the means for supplying fluid includes a hydraulic pump. 3. A method for forming a tubular fitting from a tubular blank having an interior, the method is characterized in that it comprises the steps of: providing a first die plate having a first cavity, the first die plate having a first guide post; place the tubular target in the first cavity; providing a second die plate having a second cavity, the second die plate having a second guide post; aligning the second cavity with the first cavity, to produce a shaping cavity; supporting the first die plate and the second die plate with a lower die plate, the lower die plate has a conduit; providing an upper die plate capable of moving between a first position and a second position, the upper die plate has first and second guide holes; aligning the first and second guide posts with the first and second guide holes, respectively; moving the upper die plate from the first position to the second position, to allow the first and second holes to receive the first and second guide posts, respectively; provide a fluid inside the tubular target, through the conduit; and, moving a piston towards the interior of the tubular target, to pressurize the fluid and expand the tube in such a way that it molds to the forming cavity. The apparatus according to claim 1, characterized in that it comprises at least one position bolt, the position bolt is partially positioned inside the first die plate and is located partially inside the first die plate and the second plate of die The apparatus according to claim 1, characterized in that the upper die plate is mounted to the moving part of a press. The apparatus according to claim 1, characterized in that the lower die plate is mounted to a fixed die platform. The apparatus according to claim 1, characterized in that the forming cavity has the desired cross-sectional shape of the tube formed. The apparatus according to claim 5, characterized in that the moving part of the press moves the upper die plate by means of a hydraulic cylinder assembly. 9. The apparatus according to claim 5, characterized in that the moving part of the press moves the upper die plate by a combination of motor and screw. The method according to claim 3, characterized in that the conduit is connected to an opening capable of receiving a connection member. The method according to claim 10, characterized in that the connection member is a fluid line. The method according to claim 10, characterized in that the connecting member is a pressure gauge. The method according to claim 3, characterized in that the fluid is pressurized from about 703.07 kilograms per square centimeter (10,000 pounds per square inch) to about 7030.7 kilograms per square centimeter (100,000 pounds per square inch). The method according to claim 13, characterized in that the fluid is pressurized from about 3,515.35 kilograms per square centimeter (50,000 pounds per square inch) to about 7,030.7 kilograms per square centimeter (100,000 pounds per square inch). 15. The method according to claim 3, further comprising, after the step of moving a piston, the step of removing the piston to drain the fluid and reduce the pressure of that fluid. 16. The method according to claim 15, further comprising, after the step of removing the piston, the step of lifting the upper die plate.