Common problems and maintenance methods for stamping dies.
A.The maintenance of the mould should be careful, patient and orderly, and should not be carried out blindly.The material belt should be attached to the fault repair, so that the problem can be inquired.Open the mould and check the condition of the mold, confirm the cause of the failure, find out the problem, and then make the mold cleaning to remove the mold.The force should be uniform when the die is removed, and the unloading spring is on the fixed plate and the stripper plate.A.Maintenance of mold: maintenance of continuous mold, careful, patient, step-by-step, do not blindly engage in.The material belt should be attached to the fault repair, so that the problem can be inquired.Open the mould and check the condition of the mold, confirm the cause of the failure, find out the problem, and then make the mold cleaning to remove the mold.To force wants even, dismantle for stripping the spring between the fixed plate and stripper plate and spring discharge guide pin on the immediate roof, the mould structure, the removal of the stripper to ensure balance pop-up, stripper tilt may lead to the mould punch rupture.1.Intensive maintenance: intensive is disassembled should pay attention to mold the status of the original, so that the follow-up mold when loading convenient recovery, padded or shift yuan good is to be made on the part of the thickness of the gasket and make records.To replace the convex mold, it is necessary to test whether the blanking block and the concave mold are smooth, and whether the gap between the insert and the die is even, and the gap between the die and the punch should be evenly distributed.It is necessary to check whether the effective length of the punch is sufficient to meet the required length.Replace the broken punch to find out the cause, and check whether the corresponding concave die has broken blade, and whether the cutting edge is needed.Assemble the punch to check whether there is enough clearance between the punch and the fixed block or the fixed plate, and check if there is any residual activity for the pressure block.Assemble the concave die should be placed in the horizontal, and then use the flat iron block to be used as the copper rod in the concave die surface to knock in place, cut non-diagonal force to knock in, the bottom of the concave die to chamfer.After loading, check whether the concave surface is flat with the die.Punch die and mold core after assembly to do to take care with necessary inspection, all parts are in the wrong or installed backwards, check the die and the die block is installed backwards, blanking hole blockage, whether you need new change parts stolen material, need to steal material enough, mould whether need to lock position lock.Note do stripper screw locking, lock from inside to outside, balanced cross clamping force, not one lock screw first, then lock another screw, lest cause stripper tilt cracking or punch mould precision is lower.2.Maintenance of the stripper plate: the removal of the stripper can be pried with two screwdriver, then the force is removed with the balance of the two hands.When removing difficulty, should check whether the mold clean, lock screw whether all disassembly, whether should card of material caused by mold damage, find out the reason to do the corresponding processing, must not blindly disposal.When assembling the stripper plate, clean up the punch and stripper plate, add lubricating oil to the guide column and the convex mould inlet, place it smoothly, then put the pressure in place with both hands, and repeat several times.If too tight should find out the reasons (guide pillar and guide bush orientation is normal, each part whether have damage, new change can punch over stripper position is correct,), find out the reason to do the corresponding processing.The fixed plate has a pressing block to check whether the unloading back plate is sufficient.Contact surface between the stripper and die materials, long time stamping produce indentation (stripper between the die and the material thickness reduction in capacity of aggregate is commonly 0.03 0.05 mm, when indentation seriously, will affect the material of accuracy, causing abnormal product size, instability and so on, to stripping panel board and stripper for repair or regrinding.The contour sleeve should be inspected for accuracy. It will cause the stripper to be tilted when it is not high, and its precision guide and stable elastic function will be damaged and should be maintained.3.Guide site inspection: how to cooperate with the guide column and guide sleeve, whether there are burns or wear marks, whether the mold guide oil state is normal and should be inspected.The wear and precision of the guide parts can be damaged, so that the precision of the mould can be reduced, and problems can occur in the parts of the mould. Therefore, proper maintenance and regular replacement are necessary.Check the precision of the guide material. If the guide tip (positive nail) is worn out, it has lost the proper precision and function of the material belt guide and must be replaced.Check the spring condition (stripper springs and spring lifter, etc.), to see if the fracture, or use for a long time, though not fracture, but has lost the original fatigue strength, must make regular maintenance, replacement, otherwise it will harm the mold or production is not smooth.4.Mold clearance adjustment: mold core positioning hole for frequent mold core and multiple combinations of wear and tear, causing big clearance after assembly (loose after assembly produce) or uneven clearance (positioning deviation), all can cause after cutting cross section shape, punch break easily, produce burr, etc., can be through the hedge cutting section status after inspection, make the appropriate clearance adjustment.Clearance hours, less, the cross section gap is big, the cross section is more and larger burrs, to obtain the reasonable gap in the form of displacement of yuan, adjust good, should make appropriate records, can also be marked at the edge of the concave die, etc., so that the follow-up work.Daily production should be paid attention to the collection and preservation of the original mold better condition of the material belt, if the subsequent production is not smooth or the mold changes, can be used as a reference for the mold overhaul.In addition, the auxiliary system, such as whether the top material is worn or not, whether the top material, the guide tip (positive nail) and the bushing are worn, should be checked and maintained.2.Mould the causes of common failures. Countermeasures in progressive die stamping production, stamping adverse phenomenon must be specific analysis, to take effective countermeasures, fundamentally solve the problem of what happened, so can reduce production cost, achieve smooth production.The following are the reasons for the common stamping defects in the production and the analysis of the countermeasures as follows, for the reference of the mold maintenance personnel.1.(1) causes: A, wear of the knife edge;B. The effect is not obvious after the clearance is too large.C. Knife edge collapse Angle;D, the gap is not reasonable up and down or loose;E. The mold is dislocated.(2) countermeasures: A.B. Control the machining accuracy or change of the design clearance;C.D. Adjust the clearance of blanking clearance to confirm the abrasion of hole holes or the machining accuracy of the forming parts;E. Replace the guide or regroup mode.2.(1) cause: A, large gap;B. Improper feeding;C. The stamping oil droplets are too fast and the oil is sticky;D. The mold is not demagnetized;E. The die is worn and the chip is attached to the punch mould.F. The convex mold is too short.G, the material is hard, the cutting shape is simple;H. Emergency measures.(2) countermeasures: A, control the machining accuracy of convex and concave mold or modify the design gap;B. Trim the material belt and clean the mould timely when it is sent to the appropriate position;C. Control the amount of oil dripping, or replace the oil to reduce the viscosity;D. After the study, demagnetization (more attention should be paid to the iron);E. Study the punch edge;F. Adjust the length of the concave die;G. Change the material and modify the design.To top out or trim the inclined plane or arc (note the direction).Reduce the bonding area between the end face and the cuttings of the punch edge;H, reduce the sharpness of the cutting edge, reduce the study amount of the cutting edge, increase the roughness of the surface of the straight edge of the die, and use the vacuum cleaner to absorb the waste.Slow down and slow down the dandruff.3.(1) reason: A, the hole is small;B. The leakage hole is large and the cuttings are tumbling;C. The edge of the knife is worn and the edge is large.D. The stamping oil droplets are too fast and the oil is sticky;E. The surface roughness of the straight edge of the concave mold, and the powder sintering is attached to the blade part;F. Soft material;G. Emergency measures.(2) countermeasures: A, modify the leakage hole;B. Modify the leakage hole;C. Blade trimming;D. Control dripping oil and replace oil;E, surface treatment, polishing, attention to reduce surface roughness during processing;Change the material, F, modify the blanking clearance;G. The end face of the punch blade is fixed with a slope or arc (attention direction), and the vacuum cleaner is used to blow air at the blanking hole of the washboard.4.(1) the reason: A,. The edge of the concave die is worn, and the edge is generated (the shape is large and the inner hole is small).B. Improper design size and clearance, poor machining accuracy;C. Blanking die and concave die insert, etc.D, guide pin wear, insufficient pin diameter;E. Wear of guide parts;F, feeding machine delivery distance, pressure material, relaxation adjustment;G. Improper adjustment of mold closing height;H, the material bit wear, no pressure material (strong pressure) function (the material traction of the material is caused by the small punching hole);I, the unloading insert pressure is too deep, the punching hole is large;J. Mechanical performance variation of stamping materials (unstable strength elongation);K, punching shear force on material traction, causing dimensional variation.(2) countermeasures: A.B. Modify the design and control the machining accuracy;C. Adjust its position accuracy and blanking clearance;D. Replace the guide pin;E. Replace the guide column and guide sleeve;F. Adjust the feeding machine;G. Reset the closed die height;H, grind or replace the strip insert, increase the pressure function, adjust the pressure material;I, reduce the pressure depth;J. Replace material and control incoming quality;K. The end face of the punch blade is fixed with a slope or arc (attention direction) to improve the force condition during the punching.The current material part is located on the unloading insert to add a guide function.5.(1) reason: A, feeding machine delivery distance, pressure material, relaxation adjustment;B. Variation in delivery distance in production;C. failure of feeding machine;D, the material arc, the width is extremely poor, the margin is large;E. Die stamping abnormality, the scythe bending is caused;F. Insufficient guide hole diameter and upper mold pulling material;G, bending or tearing up and down;H, improper material removal function of the guide plate, material belt;I, thin material, sent in warping;J. Improper setting of the mould and the vertical deviation of the feeder.(2) countermeasures: A, readjustment;B. Readjustment;C. Adjustment and maintenance;D. Change materials to control incoming quality;E, eliminate materials with sickle bending;F. Study the punch and punch and die;G. Adjust the power of stripping spring;H, modify the guide material, and prevent material belt;I, the feeding machine and the mold shall be equipped with upper and lower pressure materials, and the upper and lower extruding safety switch shall be set;J. Re-erect the mold.6.(1) reason: A, ramming edge (especially the carrier);B. Rough edges of materials;C. Improper punch depth (too deep or too shallow);D. The punching part is crushed.E, local pressure is too deep or pressure to partial damage;F. Mold design.(2) countermeasures: A, study the cutting edge;B. Replace the material and add the cutting edge device;C. Reset punch depth;D. Clean the mold, and solve the problem of dandruff and pressure;E. Check and adjust the correct height of the stripping and concave die insert.F. Adjust the whole bending mechanism.7.(1) causes: A, dandruff, debris blocking, card mould, etc.;B. Improper feeding, cutting half material;C. Insufficient punch strength;D. The large and small convex models are too close to each other.E, punch and die parts are too sharp;F, the blanking clearance is small;G, non-stamping oil or use of stamping oil is volatile;H, blanking clearance uneven, offset, convex, concave mode interference;I, strip block precision or wear, loss of precision guiding function;J, mold orientation is inaccurate and wear;K, convex, concave mold material selection improper, hardness improper;I, the guide material (pin) wear;M, the gasket is improperly added.(2) countermeasures: A.B. Pay attention to the feeding, timely trim the material belt, and clean the mold timely;C. Modify the design, increase the overall strength of the punch, reduce the size of the straight edge of the concave die, and pay attention to the Angle of the end face of the punch blade.D. The length of the small punch is shorter than the larger one.E. Modify the design;F. Control the machining accuracy or modification design clearance of the convex and concave mold.G. Adjust the amount of oil dripping oil or replace oil;H, check the precision of each forming part, and adjust or replace it to control the machining accuracy;I, research or replacement;J. Replace the guide column and guide sleeve, and pay attention to daily maintenance;K, replace the material and use the appropriate hardness;I. Replace the guide material;M, correction, gasket number can be few, and use steel cushion, the concave die gasket should be under the pad.8.Variation of bending deformation size (1) reason: A, guide pin wear, insufficient pin diameter;B. Poor precision and wear of the bending guide bits;C, bending and convex, die wear (pressure loss);D. Lack of molds;E. The material slip, bending and convex, the concave mode has no guide function, no prepressure is applied when bending;F. Poor mold structure and design size;G. The edge of the punching piece is caused by bending.H, convex die of bending position, more gasket of concave die, cause dimensional instability;I. variation of material thickness and size;J. Mechanical deformation of materials.(1) countermeasures: A, replace the guide pin;B. Regrind or replace;C. Regrind or replace;D. inspection and correction;E. Modify the design, add the guide position and prepress function;F. Modify the design size, break down the bending, and increase the bending and shaping;G. Study the blanking knife edge;H, adjust, adopt integral steel pad;I, replace material, control incoming material quality;J. Replace material and control incoming quality.9.(2) reason: A, burr edge;B. There is pressure wound in the stamping parts, and the mould has chips;C, convex and concave die (bending position) pressure loss or damage;D. Turn the material when cutting;E. Wear and loss of the relevant pressure parts;F. There is no consistency in the size of the relevant tearing bit and the blade wear;G. The precut depth of the relevant vulnerable position is not consistent, and the concave die is worn or broken.H, the convex and concave die of the relevant punching area has a broken edge or serious wear;I. Mold design defects.(2) countermeasures: A, research the material bit blade;B. Clean the mould and solve the problem of floating debris;C. Restudy or replace the new parts;D. Study the cutting edge, adjust or add the strong pressure function;E. Inspect and implement maintenance or replacement;F, maintenance or replacement to ensure the consistency of the tearing condition;G. Check the condition of pre-cut and convex and die, and implement maintenance or replacement;H, check the status of convex and concave mold, implement maintenance or replacement;I, modify the design, set the height adjustment or add the shaping station.10.Improper maintenance (1) reason: A, the mold has no anti-stay function, and the failure of the group mode leads to the reverse direction and misplacement, etc.;B. The inserts that have been migrated are not restored in their original form.(2) countermeasures: A, modify the mold, and increase the anti-freeze function;B. Make marks on the mold, and make necessary inspection and confirmation of the care belt after the group module, and make a written record for the inquiry.In the stamping production, the daily maintenance of the mold is of vital importance, that is, the daily attention should be paid to check whether the punching machine and the mold are in normal state, such as the refueling of the supply guide of the stamping oil.The inspection of the mold before the machine, the inspection of the blade section, the confirmation of the locking of each part, etc., can avoid the occurrence of many sudden accidents.You must first think before doing the mold repair, and carefully record the accumulation of experience.