What are the overhaul methods for stamping dies?

Overhaul methods for stamping dies

(1) Loose die: Punch or die movement exceeds single side clearance. Adjust the combination clearance.

(2) Tilted die: The straightness of the punch or die is not correct, or there is a foreign object between the templates, so that the templates cannot be flattened. Reassemble or grind to correct.

(3) Deformation of the formwork: The formwork is not hard enough or thick enough, or is deformed by external impact. Replace the formwork with a new one or correct the dismantling method.

(4) Deformation of the mould base: insufficient thickness of the mould base or uneven force, straightness of the guide pillar and guide sleeve. Grinding correction or re-fill plastic steel or replace the die holder or make the force average.

(5) Die interference: die size, position is correct, the upper and lower die positioning deviation, whether the group will be loose, the precision of the punching machine is not ì, frame die incorrect.

(6) Punching and shearing skew: the punch is not strong enough, the size of the punch is too close, the lateral force is not balanced, the punch is half skewed. Strengthen the role of stripping slant plate to guide the protection or punch to increase, small punch grinding short lt increase heel heel long early support guide, pay attention to the feeding length.

Mould damage

(1) Heat treatment buried: quenching temperature is too high or not enough, tempering times temperature time is not appropriate, quenching way time did not grasp; after using a period of time before the problem.

(2) Stamping overlap: overlapping pieces of material continue to be stamped, usually with a broken stripper plate.

(3) Blockage of scrap: the drop hole is not drilled or the size does not match or the drop is not cleaned up in time on the bed, with more damage to the punch and lower template.

(4) Punch falling: the end is fully fixed or suspended, or the screw is too fine strength is not ì, or the punch is broken.

(5) Escape hole not ì: punch pressure plate escape hole size or depth is not enough, punch and stripping plate escape part not ì usually for stripping plate damage.

(6) Foreign objects entering: products blowing out and bouncing back, die parts breaking down and falling off, screws protruding from the die surface or other objects entering the die, may damage the lower die, stripping plate or punch, guide column.

(7) Grouping error: wrongly installed parts position, direction and damage.

(8) Spring factors: spring force is not enough or broken or the height of the set is not equal to the height of the stripping plate tilt, or the spring is not always formulated, resulting in overlapping punching damage parts.

(9) Improper stamping: the working height is adjusted too low, the guide pillar loses oil, the material strip is mistakenly sent or punched half material, the peripheral equipment such as sending, putting and receiving machine is damaged, the air pipe is not installed or opened, the punching machine is abnormal, etc., the damage caused.

(10) Improper maintenance: the above-mentioned points occur as a result of not replacing or not locking the screws or not restoring them to their original state.

Dimensional variation

(1) Cutter abrasion: too large or large size (cutting shape); small size (punching hole); bad flatness. Re-grind or replace the punching die.

(2) No guide: guide pin or other positioning device does not work, the feeder is not relaxed or the guide pin diameter is not ì and cannot be corrected to guide. The positioning block is worn and the feeding distance is too long.

(3) The punching die is too short: the bend becomes too large, the chamfer is not enough, the forming is not complete.

(4) Not enough escape hole: squeezed or bracketed by injury or deformation. Clean up the escape hole or increase the escape hole and depth.

(5) Insufficient ejections: poor feeding, bending of the material strip, poor stripping, upper mould pulling, lengthening of the ejections.

(6) Improper ejections: improperly formulated ejector pin, improper spring force or too long ejections. Adjust the spring force or change the position or number of pins; pin grinding short fit.

(7) Poor guiding: the length of the guiding plate is not ì or the guiding gap is too large, or the die and the discharge machine are skewed or the distance between the die and the feeder is too long.

(8) under the material deformation: part of the bending parts can not allow the material overlap, must fall each time, or disc-shaped strain available pressure pad or shear slant à overcome.

(9) bending deformation: upper bending bend at the extrusion; near the joint hole deformation by tension, uneven force bending à tilt punch is not long enough.

(10) punching and shearing deformation: material twisted and uneven, size increase or eccentric asymmetry.

(11) impact deformation: products blown out of the air pressure is too strong or gravity fall impact deformation.

(12) floating chip extrusion: waste material floating or fine chips left on the die surface or foreign objects such as extrusion deformation.

(13) improper material: material width or plate thickness, material or material hardness is not appropriate, will also produce bad.

(14) Poor design: poor engineering arrangements and poor gap settings are difficult to overcome unless the design is changed.