1. Bracket assembly shall be installed in the middle of the maintenance sub-instrument panel of convex and concave die
Punch and die are the most frequently maintained parts in progressive die.Two methods can be used for its maintenance: when the burr of the parts is more than the specified, concave, punch edge abnormal wear, passivation, edge breakage, must be sharpened or replaced;When the number of stamping pieces reaches the specified durability (such as Cr12MoV steel: 30,000-50,000 times/grinding every edge;Steel bonded cemented carbide: 300,000-600,000 times/grinding every edge;Cemented carbide: 500,000-1 million times/grinding each edge), regardless of whether the stamping parts are qualified must be carried out on the edge of the grinding.The grinding requirements for different die steel are different: the grinding amount of alloy steel die is not more than 0.2mm each time;Each grinding of cemented carbide die should not exceed 1mm.After the grinding, the length of the convex and concave die becomes shorter, the gasket of corresponding thickness can be put in the back to ensure the synchronicity of the work of the convex and concave die in each punching station.For bending, stretching and local forming of convex and concave die to prevent foreign matter falling, it will seriously damage the forming surface, before stamping to carefully check, and compressed air will be used to clean the forming surface.If there is excessive deformation, wear or even burn on the forming surface, it should be replaced immediately, and pay attention to the lubrication of the forming surface.
2. Maintenance of unloading plate
Discharge plate is the key part of progressive die, which is responsible for guiding and protecting punch.The fit gap between hole and punch on the unloading plate of safety fixed piece is only 1/3 to 1/4 of the gap between punch and punch. Its rigidity, strength and abrasion resistance will seriously affect the guiding accuracy of punch. Therefore, the lubrication of sliding part on the unloading plate should be strengthened regularly.In the process of sharpening and changing the punch, if the size of the punch is small and the number of punch is large, it is necessary to avoid removing the punch unloading plate from the top, otherwise, it is difficult to reassemble and the guiding accuracy is difficult to reach the initial state.The key of dismantling and loading/unloading material board is to keep stable, otherwise the punch will break.
3, guide pillar guide sleeve maintenance
Precision multi-station progressive die generally adopts ball or roller guide guide sleeve, which is an important part to maintain high precision die.The lubrication is generally more concerned, but due to eccentric load caused by the guide pillar of abnormal wear often overlooked, especially in the process of high-speed stamping, guide pillar and the heat generated by the friction between the ball and roller too late out, lead to guide post thermal expansion, exacerbating the guide pillar of wear, and even burn, it seriously affected the guidance accuracy and die life, so to check the size and the surface of guide pillar, and timely replacement.For the small guide post and small guide sleeve on the unloading plate, the matching clearance shall not exceed 1/2 of the clearance between the punch and the unloading plate.
4. Spring maintenance
There are a lot of spring used on the mold, some are in the invisible state of work, once there is a problem, the damage is greater, so the implementation of spring management maintenance is very important.Spring maintenance is difficult to judge from the appearance, according to the number of parts processed and spring life to determine the cycle of replacement.If the punch is grinded for several times, the closing height of the die decreases, the replacement of the spring must be paid attention to.Stable work, compression as small as possible is the key to choose the spring;If it is a nitrogen spring, it is necessary to ensure that the stamping process is in harmony with the spring characteristic curve. The spring spring pressure should be balanced and the work should be stable to avoid impact and vibration.
5. Maintenance of other parts
After the unloading screw is used for a long time, the thread will wear out due to the action of force, and the locking force will decrease, which will cause the unloading plate is not stable, so it should be replaced regularly;The guide nail is a key part for precise control of feeding step.When the safety inspection guide pin is stopped, the precision stamping part should check its movement flexibility and sensitivity frequently.For the floating roof, it is necessary to ensure consistent movement without hysteresis and replace the spring regularly.For the mechanism with lateral stamping, it is necessary to ensure reliable wedge fixation and smooth working surface (Ra<0.2a). For the slider, it is necessary to ensure smooth movement and no obvious lateral oscillation.For the reverse punch mechanism, the reliability of the reverse punch punch guide, whether the lever is deformed or not, and whether the reset is timely;On the parts to prevent scrap rebound, to pay attention to the reliability of its movement, maintenance at any time;Fixed pieces of small screws, due to the effect of large screw force deformation, directly affect the locking force, should be replaced on time.