Common problems and solutions of stamping dies

1. Scrap jumping
(1) If the length of the punch is not enough, replace the punch according to the cutting edge of the punch to cut into a material thickness of the concave die plus 1mm
(2) The gap of the concave die is too large, and the gap can be reduced by cutting in or by using the covering machine
(3) The punch or template is not demagnetized. Use demagnetizer to demagnetize the punch or template
2. Scrap plugging
(1) The blanking hole is small or offset, and the blanking hole is enlarged to make the blanking smooth
(2) The blanking hole has a chamfer. Increase the blanking hole to remove the chamfer
(3) The knife edge is not tapered, and the linear cutting taper or the reverse expansion hole reduces the length of the straight wall position
(4) The straight wall position of the knife edge is too long, and the reverse side is drilled to shorten the straight wall position of the knife edge
(5) The edge is broken, resulting in a large edge, and the material is blocked, and the edge is reground
3. Poor front
(1) The edge of the blade is broken, resulting in excessive edge and regrinding the edge
(2) The clearance between the punch and the die is too large, the wire is cut into the block, and the clearance is reset
(3) Poor finish of concave die blade, polishing the straight wall position of blade
(4) The clearance between the punch and the die is too small, so the die is saved again and the clearance is equipped
(5) If the jacking force is too large, pull out the draper reversely and change the spring to reduce the jacking force
4. Uneven trimming
(1) Positioning offset adjusting positioning
(2) One-sided forming, material pulling and pressing force increase, and positioning adjustment
(3) Design error, resulting in uneven tool connection, cutting edge insert
(4) Feeding is not allowed to adjust the feeder
(5) The feeding step calculation is incorrect. Recalculate the step and reset the tool position
5. The punch is easy to break
(1) The closing height is too low, and the punch cutting edge is too long. Adjust the closing height
(2) Improper material positioning causes the punching punch to cut one side, adjust the positioning or the feeding device to break due to uneven stress
(3) The lower die scrap blocks the knife edge, causing the punch to break, and re-drill the large blanking hole to make the blanking smooth
(4) The fixed part of the punch (splint) and the guide part are repaired or cut into the block again to make the punch move up and down smoothly (punch)
(5) The punch is not well guided, which causes the punch to be forced on one side to re-repair the punch clearance
(6) The cutting edge of the punch is too short, and it interferes with the punching plate to change the punch again, increasing the length of the cutting edge
(7) The punch is not fixed well, and moves up and down. Fix the punch again so that it cannot move up and down
(8) The punch edge is not sharp and regrind the edge
(9) The surface of the punch is strained, and the stress is uneven during stripping. Replace the punch again
(10) The punch is too thin, too long, and the strength is not enough. Change the punch type again
(11) The punch hardness is too high, the punch material is not correct, change the punch material, and adjust the heat treatment hardness
6. Iron filings
(1) Rebar dislocation Recalculate the rebar position or bending position
(2) The bending clearance is too small, extrude iron filings to readjust the clearance, or grind the forming block, or grind the forming punch
(3) Bending punch is too sharp to repair R angle
(4) The material of the knife edge is too small. Reconnect the knife edge
(5) The pressure bar is too narrow. Grind the pressure bar again
7. Poor sprouting
(1) The center of the sprouting bottom hole does not coincide with the center of the sprouting punch to determine the correct center position, or move the position of the sprouting punch, or move it to the position of sprouting - edge high - edge low or even fracture dynamic pre-punching, or adjust the positioning
(2) The gap of the die is uneven, resulting in sprouting - high side - low or even broken sprouting gap during repair
(3) The sprouting bottom hole does not meet the requirements, resulting in the sprouting height and recalculation of the bottom hole diameter, and the pre-punching increases or reduces the diameter deviation, or even cracks
8. Poor molding
(1) The forming die punch is too sharp, which causes the material to crack. The forming punch is trimmed with R angle, and the knife edge is properly trimmed with R angle
(2) The length of the forming punch is not enough, resulting in the failure to calculate the correct length of the punch and adjust the actual length of the punch to meet the forming requirements
(3) The forming punch is too long and the material at the forming part is deformed. It is very important to determine the correct length of the punch and adjust the actual length of the punch to meet the requirements until the punch breaks
(4) The material at the forming part is not enough to cause tensile crack, calculate the expanded material, or repair the R angle, or reduce the forming height
(5) Poor positioning, resulting in poor molding adjustment positioning or feeding device
(6) The forming gap is too small to cause cracks or deformation
9. Bending dimension
(1) The mold is not adjusted in place, resulting in angle error, resulting in size deviation, poor closing height or poor angle difference
(2) Insufficient elasticity leads to poor angle, resulting in dimensional deviation. Replace the spring
(3) The material does not meet the requirements, resulting in poor angle, resulting in size change of material or re-adjustment of gap deviation
(4) The deviation of material thickness causes poor angle, which leads to the size deviation. The material thickness is determined, and the material is changed or the gap difference is readjusted
(5) Improper positioning leads to size deviation Adjust the positioning to make the size OK
(6) The design or processing error causes the repair welding and grinding between the bent male blocks, eliminates the gap between the blocks, and results in small bending size
(7) The forming company has no R angle, and the bending height is too small under the angle and other normal conditions
(8) The bending size on both sides is too large for compression reinforcement
(9) One-sided bending and drawing cause dimensional instability, increase spring force and adjust positioning
(10) The clearance is unreasonable, resulting in poor angle and dimension deviation. Repair the clearance
(11) The height of the bending tool is not enough, and the bending punch is too short to close the bending tool, which increases the height of the bending tool, so that the bending punch can close into the position of the bending tool as much as possible, resulting in more bad angle
(12) The bending speed is too fast, resulting in deformation of the bending root. Adjust the speed ratio and select a reasonable speed
(13) The structure is unreasonable, the folding knife is not inserted into the fixed template, and the groove is milled again. When the folding knife is inserted into the template for stamping, the gap becomes larger
(14) The hardness of the formed male heat treatment is not enough, resulting in the collapse of the pressing line or the flattening of the re-formed male pressing line
10. No unloading
(1) Improper positioning or feeding Adjust the positioning or feeding device
(2) The avoidance is not enough to polish the avoidance
(3) The inner guide pillar is strained, which causes poor plate movement. Replace the inner guide pillar
(4) The punch is pulled or the surface is not smooth. Replace the punch
(5) Reasonably rearrange the position of the ejector pin
(6) The jacking force is not enough, or the stripping force is not enough. Replace the jacking spring or stripping spring
(7) The punch and splint do not fit smoothly. Repair the splint and splint to make the punch fit smoothly
(8) The forming slide block is not smoothly matched. Trim the slide block and guide groove to make it fit smoothly
(9) The heat treatment of the plate is not suitable, and the plate is deformed after stamping for a period of time. Grind the plate again to correct the deformation
(10) The punch is too long or the length of the ejector pin is not enough. Increase the length of the ejector pin or replace it with a punch with appropriate length
(11) The punch is broken and the punch is replaced
(12) The template is not magnetized, and the workpiece is brought up to demagnetize the template
11. Unsmooth feeding
(1) The mold is not aligned, resulting in that the belt is not in the same line with the feeder and the mold is not aligned with the mold or adjusted feeder
(2) Leveling machine or material replacement for uneven belt
(3) Non-discharging causes irregular feeding. Refer to non-unloading solutions
(4) The positioning is too tight. Adjust the positioning
(5) The guide pin is too tight or the straight wall position is too long. Adjust the guide pin
(6) The punch is not fixed properly or is too long and interferes with the material belt. Replace the punch with proper length and fix it again
(7) The ejector pin is too short, and the belt interferes with the molding block to adjust the length of the ejector pin to avoid interference
(8) Improper arrangement of floating block position Adjust the floating block position
12. Poor riveting
(1) The closing height of the mold is not correct. The riveting is not in place. Adjust the closing height
(2) The workpiece is not placed in place, and the positioning deviation is adjusted
(3) Before riveting, if the workpiece is defective, confirm the sprout hole, and refer to the solution for the defect of the sprout hole to confirm whether the riveting hole is chamfered. If there is no chamfer, increase the chamfer
(4) The riveting punch is not long enough, and replace it with a punch with appropriate length
(5) Confirm that the riveting punch does not meet the requirements and use the riveting punch that meets the requirements
13. Missing or installing
(1) Careful wrong punch when assembling carelessly
(2) The punch has no direction mark. Mark the punch with direction
14. Install the wrong screw
(1) Do not know the thickness of the template. The thickness of the template is too long or too short
(2) Not careful and experienced enough to select proper screws
15. Disassembly and assembly of mold
(1) If the pin hole is not cleaned, clean the pin hole and pin. When removing the mold, the locating pin should be removed first. If it is easy to damage the mold, the screw should be used to guide it, and then the locating pin hole should be drilled
(2) Do not damage the pin hole when the pin is knocked down due to incorrect assembly and disassembly procedures
16. Locating pin
(1) When the hole wall is roughened and scratched, resulting in too tight mold assembly, carefully check whether the pin hole is roughened, otherwise the pin hole that cannot be punched out should be reamed again
(2) The pin hole is out of position or there is no escape hole below. Add a locating pin escape hole
17. The spring is too long
(1) Not paying attention to the depth of the spring hole, measuring the depth of the spring hole, calculating the compression amount of the spring, and selecting again can not be pressed down
(2) Not careful enough, not experienced enough, suitable spring bottom dead center