The correct use and maintenance of the most popula

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The correct use and maintenance of CNC punch molds

the service life of CNC punch molds depends on factors such as reasonable mold structure, high manufacturing accuracy, good heat treatment effect, and the correct selection of punches and the installation accuracy of punch molds. In addition, the correct use, maintenance, and maintenance of molds can not be ignored. The following points should be paid attention to:

(1) strict inspection should be carried out before the installation and use of molds from scratch, Remove the dirt and check whether the guide sleeve of the mold and the mold are well lubricated

(2) regularly check the rotary table and die mounting base of the press to ensure the coaxial accuracy of the upper and lower rotary tables

(3) install the punch and die on the turntable according to the installation procedure of the die to ensure that the direction of the punch and die is consistent, especially for those things with direction requirements (non-circular and square) shipping in Southeast Asia. We all share these things after careful consideration. We should pay more attention to the cold die to prevent wrong and reverse installation

(4) after the mold is installed, check whether the fastening screws of the mold installation base are locked correctly

(5) when the punch and die edges of the punch die are worn, they should be stopped and sharpened in time, otherwise the wear degree of the die edge will be rapidly expanded, the die wear will be accelerated, and the quality of the punch and the service life of the die will be reduced

(6) for the general mold used in batch production, there should be a backup to facilitate the rotation production and ensure the production needs

(7) the stamping personnel should use soft metal (such as copper, aluminum, etc.) to make operation tools to prevent the mold from being damaged when knocked or smashed during the installation process

(8) the mold should be handled with care during transportation, and it is not allowed to throw or touch randomly, so as to avoid damaging the cutting edge and guide of the mold

(9) the mold should be put back to the designated position in time after use, and be oiled for rust prevention

(10) ensure the service life of the mold, and regularly replace the spring of the mold to prevent the fatigue damage of the spring from affecting the use of the mold. Common problems in the use of punch dies

(1) apply for and start the formulation of relevant measurement calibration specifications. Punch wear is too fast

main reasons: ① the die clearance is too small. Generally, it is recommended that the total die clearance is 20% - 25% of the material plate thickness. ② Poor alignment of convex and concave dies, including insufficient accuracy of die base, die guide components and turret inserts, etc. ③ The punch temperature is too high, which is mainly due to the overheating of the punch caused by the continuous stamping of the same die for a long time. ④ The improper grinding method of the die leads to the annealing of the die and the aggravation of wear. ⑤ During partial unilateral punching, such as step punching, angle punching or shearing, the lateral force will make the punch deflect to one side, and the gap on this side will be reduced, resulting in serious die wear. If the installation accuracy of the machine tool die is not high, it will seriously make the punch deflect over the lower die, causing damage to the punch and die

(2) mold belt problem

mold belt will cause waste rebound, and its related factors: ① the sharpness of the mold edge, the larger the fillet of the edge, the easier it is to cause waste rebound. ② The input modulus of the mold is certain for each station of the machine tool. The input modulus of the mold is small, which is easy to cause waste rebound. ③ Whether the clearance of the mold is reasonable. If the clearance of the mold is not appropriate, it is easy to cause waste rebound. ④ Whether there is much oil on the surface of the processed plate. ⑤ Spring fatigue damage

methods to prevent the mold from being loaded: ① use a special anti loading concave die. ② The mold is often sharpened to keep sharp and demagnetized. ③ Increase die clearance. ④ The inclined blade die is used to replace the flat blade die. ⑤ Mold installation ejector. ⑥ Reasonably increase the entry modulus of the die. ⑦ Check the fatigue strength of the die spring or discharge sleeve

(3) mold neutrality problem

mold is easy to occur in use. The wear amount of each side of the punching core is different, and some parts have large scratches, which wear faster. This situation is particularly obvious on thin and narrow rectangular mold. The main reasons for this problem are: ① the design or machining accuracy of the turret of the machine tool is insufficient, which is mainly due to the poor alignment of the mold mounting base of the upper and lower turntables. ② The design or machining accuracy of the die cannot meet the requirements. ③ The precision of the guide sleeve of the die punch is not enough. ④ Improper choice of die clearance. ⑤ The mold mounting base or mold guide sleeve is not well aligned due to long-term wear and tear

in order to prevent inconsistent die wear, it should: ① regularly use centering mandrel to check and adjust the neutrality of machine tool turret and mounting base. ② Replace the mold guide sleeve in time and select the convex and concave mold with appropriate clearance. ③ Adopt full lead mold. ④ Strengthen the hearts of operators, find out the causes in time after discovery, so as to avoid greater losses

(4) use of special forming molds

in order to meet production needs, forming molds or special molds are often used, mainly including bridge molds, shutter molds, counterbore molds, hole turning and thread tapping molds, boss molds, stretching molds, combined molds, etc. the use of special or forming molds can greatly improve production efficiency, but the price of forming molds is high, usually 4 ~ 5 times that of ordinary molds. In order to avoid mistakes, we should pay attention to and follow the following principles:

① check the direction during mold installation to ensure that the installation direction of the convex and concave mold of the mold is consistent

② correctly adjust the stamping depth of the die according to the requirements, and each adjustment should not exceed 0.15mm

③ use a lower punching speed

④ the plate should be flat without deformation or warping

⑤ the forming position should be as far away from the clamp as possible

⑥ when using the forming die, the downward forming operation should be avoided

⑦ when stamping, press with the ordinary die first, and then use the forming die

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