Solutions to the defects of metal stamping parts and how to install them on the punch and debug them

{1}Solutions to defects of metal stamping parts

1.Solutions to wrinkling

If the wrinkling problem occurs around the parts,it can be solved by adjusting the blank holder force.In production,it will increase the air cushion pressure and reduce the height of the balance weight,and innovate the service pressing force to wrinkles.In the case of tensile conical parts and hemispherical parts,the material is in the suspended state at the beginning of stretching,which makes it easy to wrinkle the side wall.Therefore,in addition to increasing the pressure,it is also necessary to increase the number of tensile ribs and change the shape of ribs,so that the radial tensile force in the plate is deeply served by innovation,so as to wrinkle.Alternatively,the gap of the pressing surface can be adjusted to distinguish the bending deformation of the straight line from the elongation deformation area,and the gap of the pressing surface should be increased so that the pressing surface can maintain the function of pressing material in the process of material movement,so as to avoid wrinkling.

2.Countermeasures to crack

If there is a problem of tension crack,the height of the balance weight of the blank holder ring of the drawing die needs to be adjusted to adapt to the deviation of equipment accuracy and the gap of the concave convex die,so as to achieve force balance.Secondly,if the fillet radius of the die is too small,it is easy to crack.Therefore,it is necessary to increase the fillet radius of the die to improve the degree of crack.It can also change the shape of the stamping die before deep drawing,give full play to the advantages of process incision and reduce the tensile crack problem caused by material accumulation,or change the position and shape of the tensile rib,and use semi-circular rib or trapezoidal rib according to the thinning rate of the material.

3.Countermeasures for rebound

At present,the main method to solve the springback problem is to supplement the forming process with the pressing surface,which can reduce the drawing.This method is mainly used when the pressing surface is on the flange surface of the component.Usually,the pressing surface will have a certain bending.In order to reduce the drawing and protect the blank from sticking and pressing on the pressing surface,the local pressing surface needs to be processed into an inclined angle of about 60 degrees.If the included angle is too small,it will lead to the problem of wrinkles,but if the included angle is too large,it will also cause serious rebound.At the same time,it is also necessary to avoid ripple in the drawing process,mainly because the punch has a definite role in drawing blank.You can avoid springback and protect the quality of parts by controlling the drawing distance.

4.Strengthen the use of simulation technology

In the forming process of metal and hardware stamping parts,the forming and disposal simulation software of plates requires operators to have sufficient technical ability and experience accumulation.At present,due to the great differences in experience and technology between different personnel,the simulation results of different personnel will be very different.In order to make good use of simulation technology,enterprises need to increase investment,improve the level of computer hardware and software,and strengthen the introduction of talents to protect enterprises from further making full use of optimized simulation software.At the same time,enterprises also need to strengthen the training of talents,improve the computer level of workers and meet the operation requirements of stamping forming simulation.

{2}How to install and debug aluminum alloy stamping parts on the punch press

Installing and debugging aluminum alloy stamping parts on the press is a basic skill that every die worker should have,but many new stamping and die workers often can't master it skillfully.Let's share how to install and debug aluminum alloy stamping parts on the press.

1)First check whether the operation of the punch is normal and whether the die is intact.Stop the punch at the top dead center,adjust the stop screws on both sides of the slider to the high position,and wipe the contact surface between the punch and the installed die.

2)Install the die.For the die without guide device,first take the upper die to the workbench,place a thick board or slightly soft and flat thick material under the upper die for the stainless steel stamping part,and push them under the sliding block together.For the mold with guide device,the upper and lower molds with the guide parts in the matching state can be pushed under the sliding block together with the selected sizing block.

Turn the flywheel by hand or press the inching button(for large and medium-sized punches)to move the slider down,and move the upper die at the same time to align the die handle with the die handle hole of the slider.For the upper die without die handle,the upper die shall be placed at the lower part of the center of the slider,and the bolts in the T-shaped groove of the slider shall be aligned with the open groove or fixing hole of the upper die.Then slowly lower the sliding block until the lower plane of the sliding block is close to the upper plane of the upper formwork of the die,and tighten the bolts to fix the upper formwork.

3)Install the lower die.For the punch die without guide device,remove the skid under the upper die first,and then plug the lower die together with the selected sizing block under the upper die.Move the sliding block downward and horizontally move the position of the lower die at the same time to make the matching gap between the working parts of the upper and lower dies roughly uniform.Fix the lower die slightly,and then insert it with red copper sheet and hard paper for fine adjustment.In case of straight edge,a feeler gauge can also be used,or the aluminum alloy stamping part punched last time can be used to calibrate the die.After the gap is adjusted,the lower die can be fixed.

4)Adjust the closing height of the punch press.Adjust the closing height according to the of the punch required by the die into the female die,and tighten the locking mechanism after it is appropriate.Then empty punch and test punch.For adjustable stroke punch,the stroke should be adjusted first,and then the closing height.

5)Adjust the charging and jacking device,adjust the slider to the top dead center position,and adjust the stop screw downward to make its lower end contact the charging cross arm.Try punching once to see if you can lay off the material.If you can't cut the material,continue to adjust the stop screw down.Try to adjust it.Don't adjust it too much.Too much will damage the mold.