Mold cleaning is a key process in mold maintenance and maintenance, and it is also a bottleneck restricting mold maintenance. Because the speed of mold manufacturing is much faster than the speed of mold cleaning, and the mold is quickly cleaned, it is ready for the next production, so the time left for mold cleaning is quite limited. How to clean the mold?
1. Standardized cleaning procedure
Systematic mold maintenance is based on maintenance requirements and consistency of maintenance operations. In order to achieve the "cost-effective" goal, cleaning molds must be careful: develop a detailed mold cleaning program. When cleaning different parts of the mold, such as internal cleaning of the press, wiping along the edge, regular cleaning, and main cleaning, the cleaning operation method is also different.
After a certain period of operation of the mold and after visual inspection of plating wear, track marks, and mold residue content in the venting and non-venting areas, the technician can determine the procedure and frequency of mold cleaning by visual inspection. Therefore, it is important to understand the cycle of safe operation of the mold and to document the observations of residue accumulation and wear inside the mold.
Based on the mold having a certain operating cycle, all molds should be accompanied by documentation of the relevant maintenance procedures and maintenance intervals. In general, controlling the internal grease level and gear broaching, sliders, internal shaft pins and bushings, and other moving parts are key to ensuring stable production. Other factors affecting production include contamination or blockage of the waterline and sprinklers, leakage of manifolds, rust and corrosion due to water leakage or condensation.
2. What level of cleaning is enough
Usually, when the molding process is completed, dirt or residue is often left on the mold, and the final cleaning requirements are different for different kinds of residues. Resins such as polyvinyl chloride produce hydrogen chloride gas, which can corrode many types of die steel. Some other residues are separated from the flame retardant and the antioxidant, which can cause corrosion to the steel. There are also some pigment colorants that can rust the steel and the rust is difficult to remove. Even ordinary sealed water, if placed on the surface of an untreated mold for a long time, will also cause damage to the mold.
Therefore, the mold should be cleaned as necessary according to the established production cycle. Each time the mold is removed from the press, it is first necessary to open the mold vents to remove all oxidized dirt and rust from the mold and non-critical areas of the stencil to prevent it from slowly corroding the steel surface and edges. In many cases, even if the cleaning is completed, some uncoated or rust-prone mold surfaces will soon appear rust again. Therefore, even if it takes a long time to brush the unprotected mold, the surface rust cannot be completely avoided.
Many molds now have "self-cleaning" vent lines that have a high gloss. By rinsing and polishing the vents to the degree of polishing of SPI#A3, or by milling or grinding, the residue is discharged to the waste area of the vent line to prevent residue from adhering to the surface of the roughing stand. . However, if the operator uses a coarse brushing pad, emery cloth, sandpaper, grindstone or a brush with nylon bristles, brass or steel to manually grind the mold, it will cause excessive cleaning of the mold.
In general, when the surface of the mold is subjected to high-pressure pulverization cleaning using hard plastics, glass beads, walnut shells, and aluminum pellets as an abrasive, if the abrasive is used too frequently or improperly used, the polishing method also causes The surface of the mold is filled with voids, and it is easy for the residue to adhere to it, resulting in more residue, abrasion, or premature rupture or burrs of the mold, which is more detrimental to the cleaning of the mold.
Therefore, by finding a cleaning device suitable for the mold and the processing process, and referring to the cleaning method and the cleaning cycle recorded in the archive document, the maintenance time can be saved, and at the same time, the wear of the mold can be effectively reduced.