Pre-tightening type heavy press equipment and mounting and pressing method

Abstract

The invention relates to the technical field of press equipment, in particular to pre-tightening type heavy press equipment and an installing and pressing method. The upper cross beam and the lower cross beam are connected through the stand columns to form a rack structure of the press, the hydraulic cylinder is fixed to the upper cross beam, and the piston rod of the hydraulic cylinder drives the upper die to vertically move in the middle of the rack, so that the upper die makes contact with the lower die when pressed downwards, and a forging material is pressed into a forging workpiece; pre-tightening structures are additionally arranged on the upper portion of an upper cross beam and the lower portion of a lower cross beam, the pre-tightening structures are tightened in advance before pressing is started, the two ends of the upper portion of the upper cross beam and the two ends of the lower portion of the lower cross beam are pre-tightened, downward strain is generated in the middle of the upper cross beam, upward strain is generated in the middle of the lower cross beam, and then pressing action is conducted. The downward pressing force of the hydraulic cylinder is counteracted by the strain in the middle of the lower cross beam, and the upward counter-acting force of the forging workpiece is counteracted by the strain in the middle of the upper cross beam, so that the arching and bending conditions of the upper cross beam and the lower cross beam are improved.

Description

Technical Field

[0001] The invention relates to the technical field of press equipment, in particular to pre-tightened heavy-duty press equipment and an installation and pressing method. Background Art

[0002] The press is an important basic equipment in the machinery manufacturing industry, and its application involves various fields of national economy, military and national defense. The elastic deformation of the press frame depends on the design stiffness of the frame structure. Insufficient stiffness will cause defects such as inadequate size and misalignment in the forged workpiece. The higher the stiffness of the equipment and the smaller the elastic deformation of the structure, the higher the precision of the formed forgings. The hydraulic press frame consists of an upper crossbeam, a lower crossbeam and a column. The hydraulic cylinder set on the upper crossbeam drives the slider to press the workpiece. The pressing force and reaction force of the hydraulic cylinder act on the lower crossbeam and the upper crossbeam respectively. The pressing force and reaction force during pressing drive the middle position of the upper and lower crossbeams to arch upward and downward respectively, causing the press to deform. When the pressing force of the hydraulic cylinder deviates from the center line, the slider and the lower crossbeam are no longer parallel, but produce a certain angle, which causes the upper and lower molds to be misaligned, affecting the precision of the forged workpiece. Summary of the invention

[0003] The technical problem to be solved by the present invention is that the pressing force and reaction force of the hydraulic cylinder of the existing press act on the lower beam and the upper beam respectively, causing the press to deform and affecting the accuracy of the forged workpiece.

[0004] In order to solve the above problems, the present invention provides a press equipment and installation pressing method which can improve the rigidity of the upper beam and the lower beam of the press, thereby ensuring the accuracy of the forged workpiece; The first technical solution of the present invention is: A pre-tightening heavy-duty press equipment comprises an upper crossbeam, a lower crossbeam, a column, a hydraulic cylinder, an upper mold and a lower mold. The upper crossbeam and the lower crossbeam are connected by the column. The hydraulic cylinder is fixed on the upper crossbeam, and the piston rod of the hydraulic cylinder passes through the upper crossbeam and is fixedly connected to the upper mold. The lower mold is fixed on the lower crossbeam. The upper part of the upper crossbeam and the lower part of the lower crossbeam are respectively provided with pre-tightening structures. The upper part of the upper crossbeam and the lower part of the lower crossbeam are pre-tightened at both ends by the pre-tightening structures. When the piston rod of the hydraulic cylinder drives the upper mold to move toward the lower mold, the pre-tightening structure on the upper crossbeam is used to offset the reaction force of the hydraulic cylinder, and the pre-tightening structure on the lower crossbeam is used to offset the pressing force of the hydraulic cylinder.

[0005] Preferably, a further technical solution of the present invention is: The pre-tensioning structure includes two anchor seats, the bottoms of the two anchor seats are respectively fixed at the two ends of the upper part of the upper beam or the two ends of the lower part of the lower beam, a plurality of pre-tensioning ropes are tied between the two anchor seats, and a plurality of conical clips are fixed to the outer ends of the two anchor seats, and the pre-tensioning ropes are passed through the conical clips to ensure that the two ends of the pre-tensioning ropes can only be pulled toward the outer ends, and the pre-tensioning force of the pre-tensioning ropes causes the upper part of the upper beam and the lower part of the lower beam to generate strains that offset the reaction force and the pressing force.

[0006] There are four columns, which are respectively fixed at the four corners of the upper beam and the lower beam, a slider is fixed on the upper part of the upper mold, the upper part of the slider is fixedly connected to the piston rod of the hydraulic cylinder, and the four corners of the slider are slidably matched with the four columns. The piston rod and the upper mold are connected through the slider.

[0007] The four corners of the slider are all fixed with sliding claws, and the outer ends of the sliding claws are provided with sliding grooves that match the columns, and the sliding claws slide in cooperation with the columns through the sliding grooves. The sliding claws enable the slider to be stably connected to the columns.

[0008] A tie rod is axially passed through the middle of each column, and the upper and lower ends of the tie rod pass through the upper beam and the lower beam respectively, and the outer end of the tie rod is threadedly connected with a nut. The tie rod increases the connection stability between the column and the upper beam and the lower beam.

[0009] The second technical solution of the present invention is: A pre-tightening heavy-duty press installation and pressing method, applied to the above-mentioned press equipment, comprises the following steps: Step 1: Connect the upper crossbeam and the lower crossbeam through the column, and fix the hydraulic cylinder on the upper crossbeam so that the piston rod of the hydraulic cylinder is downward; fix the upper mold at the front end of the piston rod of the hydraulic cylinder, fix the lower mold on the upper part of the lower crossbeam, and calibrate the upper mold and the lower mold so that the vertical positions of the upper mold and the lower mold correspond; Step 2: fix the pre-tightening structure at the upper part of the upper crossbeam and the lower part of the lower crossbeam, and pre-tighten the two ends of the pre-tightening structure, so that the middle position of the upper crossbeam generates a downward slightly arched strain, and the middle position of the lower crossbeam generates an upward slightly arched strain; Step 3: Place the forging material in the lower die, then control the piston rod of the hydraulic cylinder to extend, drive the upper die to move downward, until the upper die and the lower die are in close contact, and press the forging material into a forged workpiece according to the shape of the die. At this time, the strain in the middle of the lower beam offsets the downward pressing force of the hydraulic cylinder, and the strain in the middle of the upper beam offsets the upward reaction force of the forged workpiece. Step 4: After forging is completed, the piston rod of the hydraulic cylinder is controlled to retract, driving the upper die to move upward, taking out the forged workpiece and waiting for the next forging workpiece pressing.

[0010] Compared with the prior art, the present invention using the above-mentioned technical solution 1 and technical solution 2 has the following beneficial effects: The present invention connects the upper crossbeam and the lower crossbeam through columns to form a frame structure of the press, fixes the hydraulic cylinder on the upper crossbeam, and drives the upper die to move vertically in the middle of the frame through the piston rod of the hydraulic cylinder, so that the upper die contacts the lower die when pressing downward, and the forging material is pressed into a forged workpiece; by adding a pre-tightening structure to the upper part of the upper crossbeam and the lower part of the lower crossbeam, the pre-tightening structure is tightened in advance before starting to press, so that the upper ends of the upper crossbeam and the lower ends of the lower crossbeam are pre-tightened, and after pre-tightening, a downward strain is generated in the middle position of the upper crossbeam, and an upward strain is generated in the middle position of the lower crossbeam, and then a pressing action is performed, the downward pressing force of the hydraulic cylinder is offset by the strain in the middle position of the lower crossbeam, and the upward reaction force of the forged workpiece is offset by the strain in the middle position of the upper crossbeam, thereby improving the arching and bending conditions of the upper and lower crossbeams. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic structural diagram of Embodiment 1 of the present invention; Figure 2 Schematic diagram of the upper crossbeam structure of the first embodiment of the present invention; Figure 3 is a schematic diagram of the anchor seat structure of the first embodiment of the present invention; Figure 4 It is a schematic diagram of the use of the through-type jack and the anchor seat according to the first embodiment of the present invention; Figure 5 is a schematic diagram of the bending strain of the upper beam in the second embodiment of the present invention; In the figure: 1. column; 11. upper crossbeam; 12. lower crossbeam; 13. pull rod; 14. nut; 15. hydraulic cylinder; 16. slider; 161. sliding claw; 17. upper mold; 18. lower mold; 2. pre-tightening rope; 3. anchor seat; 4. conical clip; 5. through-type jack; 6. jack bracket; 7. anchor plate. DETAILED DESCRIPTION

[0012] The present invention will be further described below in conjunction with embodiments, the purpose of which is only to provide a better understanding of the content of the present invention. Therefore, the examples given do not limit the protection scope of the present invention.

[0013] See attached Figure 1-5The first embodiment of the present invention discloses a preloaded heavy-duty press device, including an upper crossbeam 11, a lower crossbeam 12, a column 1, a hydraulic cylinder 15, an upper mold 17 and a lower mold 18. The upper crossbeam 11 and the lower crossbeam 12 are connected through the column 1. The cylinder body of the hydraulic cylinder 15 is embedded in the upper crossbeam 11 and fixedly connected through the end flange bolts. The piston rod of the hydraulic cylinder 15 is vertically facing the lower mold 18, and a slider 16 is fixed to the front end of the piston rod of the hydraulic cylinder 15. The bottom of the slider 16 is connected to the upper mold 17 through a screw. The lower mold 18 is fixed to the upper part of the lower beam 12 by bolts, and the upper part of the upper beam 11 and the lower part of the lower beam 12 are respectively provided with pre-tightening structures, and the upper ends of the upper beam 11 and the lower ends of the lower beam 12 are pre-tightened by the pre-tightening structures. When the piston rod of the hydraulic cylinder 15 drives the upper mold 17 to move toward the lower mold 18, the pre-tightening structure on the upper beam 11 is used to offset the reaction force of the hydraulic cylinder 15, and the pre-tightening structure on the lower beam 12 is used to offset the pressing force of the hydraulic cylinder 15.

[0014] In this embodiment, the pre-tightening structure includes two anchor seats 3, the bottoms of the two anchor seats 3 are respectively fixed to the two ends of the upper part of the upper beam 11 or the two ends of the lower part of the lower beam 12 by bolts through anchor plates 7, a plurality of anchor holes are opened in the two anchor seats 3, a plurality of pre-tightening ropes 2 are tied between the two anchor seats 3, the length direction of the pre-tightening rope 2 is perpendicular to the displacement direction of the upper mold 17, the two ends of the pre-tightening rope 2 are respectively inserted into the anchor holes of the two anchor seats 3, and a plurality of conical clips 4 are fixed to the outer ends of the two anchor seats 3. Specifically, the conical clip 4 adopts a steel strand clip, and the conical clip 4 is inserted into the outer side of the anchor hole from the outside to the inside, so that the large diameter end of the conical clip 4 faces outward and the small diameter end faces inward, and the pre-tightening rope 2 is passed through the conical clip 4 to ensure that the two ends of the pre-tightening rope 2 can only be pulled toward the outer end. During pre-tightening, a jack bracket 6 is fixed on the outside of the two anchor seats 3, and the pre-tightening rope 2 on the outside of the anchor seat 3 is passed through the jack bracket 6 and inserted into the through-type jack 5. The jack bracket 6 adopts a tool anchor limit plate, which limits the movement of the conical clamp 4. The through-type jack 5 is used to pull the two ends of the pre-tightening rope 2 outward to tighten the pre-tightening rope 2. After the through-type jack 5 is loosened, the conical clamp 4 prevents the two ends of the pre-tightening rope 2 from shrinking to the middle, thereby achieving a pre-tightening effect. After pre-tightening, the through-type jack 5 and the jack bracket 6 are removed, and the pre-tightening rope 2 at the outer end of the anchor seat 3 is tied and tied. Through the pre-tightening force of the pre-tightening rope 2, the upper part of the upper beam 11 and the lower part of the lower beam 12 generate strains that offset the reaction force and the pressing force.

[0015] In this embodiment, four columns 1 are provided, and the columns 1 are rectangular columns, which are respectively fixed at the four corners between the upper crossbeam 11 and the lower crossbeam 12. The four corners of the slider 16 are fixed with sliding claws 161, and the outer side of the sliding claw 161 is provided with a right-angled slide groove, which matches the inner corner position of the column 1. When the piston rod of the hydraulic cylinder 15 drives the slider 16 to move, the sliding claw 161 abuts against the column 1 through the slide groove to slide up and down, and the slider 16 is stably connected to the column 1 through the sliding claw 161.

[0016] In this embodiment, the pre-tightening structures of the upper cross beam 11 and the lower cross beam 12 can be provided in multiple groups. By setting different pre-tightening forces in each group of pre-tightening structures, the pre-tightening degree at different positions of the upper cross beam 11 and the lower cross beam 12 can be controlled.

[0017] In this embodiment, a tie rod 13 is axially passed through the middle of each column 1, and the upper and lower ends of the tie rod 13 pass through the upper cross beam 11 and the lower cross beam 12 respectively, and are provided with threaded sections, and nuts 14 are threadedly connected on the tie rod 13 protruding from the upper cross beam 11 and the lower cross beam 12. The tie rod 13 increases the connection stability between the column 1 and the upper cross beam 11 and the lower cross beam 12.

[0018] In this embodiment, the pre-tensioning rope 2 adopts a fiber rope with a high elastic modulus. The fiber rope can not only provide a pre-tensioning force to offset the tensile stress generated by part of the working load, but more importantly, under the action of the same residual tensile stress, the fiber rope has a large stiffness and can reduce the deformation of the upper beam 11 and the lower beam 12 compared to the traditional rib plate, thereby achieving the effect of improving the frame stiffness.

[0019] Embodiment 2 of the present invention discloses a pre-tightening heavy-duty press installation and pressing method, which is applied to the above-mentioned press equipment and includes the following steps: Step 1: Install the press equipment: connect the upper crossbeam 11 and the lower crossbeam 12 through the column 1, and fix the hydraulic cylinder 15 on the upper crossbeam 11, so that the piston rod of the hydraulic cylinder 15 is downward; fix the upper mold 17 at the front end of the piston rod of the hydraulic cylinder 15, fix the lower mold 18 on the upper part of the lower crossbeam 12, and calibrate the upper mold 17 and the lower mold 18 so that the vertical positions of the upper mold 17 and the lower mold 18 correspond; Step 2: pre-tighten the upper crossbeam 11 and the lower crossbeam 12: fix the pre-tightening structure at the upper part of the upper crossbeam 11 and the lower part of the lower crossbeam 12, and pre-tighten the two ends of the pre-tightening structure, so that the middle position of the upper crossbeam 11 generates a downward slightly arched strain, and the middle position of the lower crossbeam 12 generates an upward slightly arched strain; Step 3: Pressing and forging: Place the forging material in the lower die 18, then control the piston rod of the hydraulic cylinder 15 to extend, drive the upper die 17 to move downward, until the upper die 17 and the lower die 18 are in close contact, and press the forging material into a forged workpiece according to the shape of the die. At this time, the strain at the middle position of the lower crossbeam 12 offsets the downward pressing force of the hydraulic cylinder 15, and the strain at the middle position of the upper crossbeam 11 offsets the upward reaction force of the forged workpiece; Step 4: After forging is completed, the piston rod of the hydraulic cylinder 15 is controlled to retract, driving the upper die 17 to move upward, taking out the forged workpiece and waiting for the next forging workpiece pressing.

[0020] The present invention connects the upper crossbeam 11 and the lower crossbeam 12 through the column 1 to form the frame structure of the press, fixes the hydraulic cylinder 15 on the upper crossbeam 11, and drives the upper die 17 to move vertically in the middle of the frame through the piston rod of the hydraulic cylinder 15, so that the upper die 17 contacts with the lower die 18 when pressing down, and presses the forging material into a forged workpiece; by adding a pre-tightening structure on the upper part of the upper crossbeam 11 and the lower part of the lower crossbeam 12, the pre-tightening structure is tightened in advance before starting to press, so that the upper ends of the upper crossbeam 11 and the lower ends of the lower crossbeam 12 are pre-tightened, after pre-tightening, the middle position of the upper crossbeam 11 generates downward strain, and the middle position of the lower crossbeam 12 generates upward strain, and then the pressing action is performed, the downward pressing force of the hydraulic cylinder 15 is offset by the strain in the middle position of the lower crossbeam 12, and the upward reaction force of the forged workpiece is offset by the strain in the middle position of the upper crossbeam 11, thereby improving the arching and bending of the upper crossbeam 11 and the lower crossbeam 12. The pre-tensioning principle of the present invention is similar to the tensioning principle of prestressed steel strands of a bridge. When the pre-tensioned fiber ropes are fixed at the two ends of the upper part of the upper beam 11, the upper part of the upper beam 11 is subjected to the retraction force of the fiber ropes, generating a retraction force moving toward the middle, so that the two ends of the upper part of the upper beam 11 tend to retract toward the middle, causing the middle position of the upper beam 11 to have a tendency to arch and deform downward, but no actual deformation occurs. When the upper beam 11 is subjected to the reaction force of the pressing work, the reaction force acts on the middle position of the upper beam 11, causing the tendency of the middle position of the upper beam 11 to arch and deform downward to resist the reaction force, thereby offsetting the reaction force and avoiding deformation of the upper beam 11 during the pressing work. The offsetting effect of the lower beam 12 is the same as that of the upper beam 11.

[0021] The present invention uses a lightweight, high-strength, high-elastic modulus fiber rope to replace the reinforcing rib plate. With the cooperation of a detachable pre-tightening structure, the anchor points of the upper and lower beams 12 of the press can be arbitrarily changed, and the pre-tightening force can be arbitrarily adjusted, thereby turning the traditional frame beam with fixed stiffness into a variable stiffness beam with arbitrarily adjustable stress. This method can turn the press frame into an equipment structure with flexible stiffness control according to the forging accuracy requirements of the workpiece and the eccentric pressing changes of the press, thereby improving the versatility of the frame and reducing the weight of the equipment. It is a composite frame structure design method with variable stiffness, which is suitable for promotion and use.

[0022] The above description is only a preferred feasible embodiment of the present invention, and does not limit the scope of rights of the present invention. All equivalent changes made using the contents of the present specification and its drawings are included in the scope of rights of the present invention.

Claims

1. A preloaded heavy-duty press equipment, comprising an upper crossbeam, a lower crossbeam, a column, a hydraulic cylinder, an upper mold and a lower mold, wherein the upper crossbeam and the lower crossbeam are connected by the column, the hydraulic cylinder is fixed on the upper crossbeam, and the piston rod of the hydraulic cylinder passes through the upper crossbeam and is fixedly connected to the upper mold, and the lower mold is fixed on the lower crossbeam, characterized in that: The upper part of the upper crossbeam and the lower part of the lower crossbeam are respectively provided with pre-tightening structures, through which the upper and lower ends of the upper crossbeam and the lower crossbeam are pre-tightened. When the piston rod of the hydraulic cylinder drives the upper mold to move toward the lower mold, the pre-tightening structure on the upper crossbeam is used to offset the reaction force of the hydraulic cylinder, and the pre-tightening structure on the lower crossbeam is used to offset the pressing force of the hydraulic cylinder.

2. The preloaded heavy-duty press equipment according to claim 1 is characterized in that: The pre-tensioning structure includes two anchor seats, the bottoms of the two anchor seats are respectively fixed to the two ends of the upper part of the upper beam or the two ends of the lower part of the lower beam, a plurality of pre-tensioning ropes are tied between the two anchor seats, and a plurality of conical clips are fixed to the outer ends of the two anchor seats, and the pre-tensioning ropes are passed through the conical clips to ensure that the two ends of the pre-tensioning rope can only be pulled toward the outer ends.

3. The preloaded heavy-duty press equipment according to claim 1 is characterized in that: There are four columns, which are respectively fixed at the four corners of the upper beam and the lower beam. A slider is fixed on the upper part of the upper mold. The upper part of the slider is fixedly connected to the piston rod of the hydraulic cylinder. The four corners of the slider are slidably matched with the four columns.

4. The pre-tightening heavy-duty press equipment according to claim 3 is characterized in that: The four corners of the sliding block are all fixed with sliding claws, and the outer ends of the sliding claws are provided with sliding grooves that cooperate with the columns, and the sliding claws slide in cooperation with the columns through the sliding grooves.

5. The preloaded heavy-duty press equipment according to claim 1, characterized in that: A pull rod is axially passed through the middle of each column, the upper and lower ends of the pull rod pass through the upper cross beam and the lower cross beam respectively, and the outer end of the pull rod is threadedly connected with a nut.

6. A method for installing and pressing a pre-tightening heavy-duty press, applied to the press equipment according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1: Connect the upper crossbeam and the lower crossbeam through the column, and fix the hydraulic cylinder on the upper crossbeam so that the piston rod of the hydraulic cylinder is downward; fix the upper mold at the front end of the piston rod of the hydraulic cylinder, fix the lower mold on the upper part of the lower crossbeam, and calibrate the upper mold and the lower mold so that the vertical positions of the upper mold and the lower mold correspond; Step 2: fix the pre-tightening structure at the upper part of the upper crossbeam and the lower part of the lower crossbeam, and pre-tighten the two ends of the pre-tightening structure, so that the middle position of the upper crossbeam generates a downward slightly arched strain, and the middle position of the lower crossbeam generates an upward slightly arched strain; Step 3: Place the forging material in the lower die, then control the piston rod of the hydraulic cylinder to extend, drive the upper die to move downward, until the upper die and the lower die are in close contact, and press the forging material into a forged workpiece according to the shape of the die. At this time, the strain in the middle of the lower beam offsets the downward pressing force of the hydraulic cylinder, and the strain in the middle of the upper beam offsets the upward reaction force of the forged workpiece. Step 4: After forging is completed, the piston rod of the hydraulic cylinder is controlled to retract, driving the upper die to move upward, taking out the forged workpiece and waiting for the next forging workpiece pressing.

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