The processing of precision plastic molds mainly includes the combination of the base plate, the die assembly and the die combination. The female mold with variable cavity is composed of card plates, and the punch with variable core is composed of punch combination base plate, punch assembly, punch combination card plate, cavity cutting component and side section combination plate. Coordinated change of mold convex, concave mold and auxiliary forming system. It can process a series of plastic parts of different shapes and sizes.
Although the mold design is carried out under the expected process conditions when selecting molding materials and molding equipment, people's understanding is often imperfect. How is the quality. After the discovery is always made, repair the model to eliminate the error.
There are many types of bad phenomena in plastic parts, and the reasons are very complicated. There are reasons for the mold and the reasons for the process conditions. The two are often only combined. Before repairing the mold, a detailed analysis and research should be carried out according to the actual situation of the bad phenomena in the plastic parts, and the remedy methods should be proposed after finding out the reasons for the defects of the plastic parts. Because the molding conditions are easy to change, the general practice is to change the molding conditions first, and only consider repairing the mold when changing the molding conditions cannot solve the problem.
"Mold plays an extremely important role in modern industry, and its quality directly determines the quality of the product. Improve the service life and precision of the mold. Shortening the manufacturing cycle of the mold is a technical problem that many companies urgently need to solve, but in the process of using the mold There are often failure forms such as slump, deformation, wear, and even breakage." Luo Baihui, a mold expert, said that there are many ways to repair molds, such as electric spark technology, argon arc welding repair, laser surfacing technology, and electric brush plating.
The welding is performed by using the arc burning between the continuously fed welding wire and the workpiece as the heat source, and the gas shielded arc sprayed from the torch nozzle is used for welding. At present, argon arc welding is a commonly used method, which can be applied to most major metals, including carbon steel and alloy steel. Melting extremely inert gas shielded welding is suitable for stainless steel, aluminum, magnesium, copper, titanium, zirconium and nickel alloys. Due to its low price, it is widely used in mold repair welding. However, it has the disadvantages of large welding heat affected area and large welding spot. Precision mold repair has been gradually replaced by laser welding.
The brush plating technology uses a special DC power supply equipment. The positive pole of the power supply is connected to the plating pen as the anode during brush plating; the negative pole of the power supply is connected to the workpiece as the cathode during brush plating. The plating pen usually uses high-purity fine graphite block as the anode. Anode material, graphite block wrapped with cotton and wear-resistant polyester cotton cover. When working, the power supply components are adjusted to a suitable voltage, and the plating pen immersed in the plating solution is in contact with the surface of the repaired workpiece at a certain relative speed, and the metal ions in the plating solution diffuse to the workpiece under the action of the electric field force. On the surface, the electrons obtained on the surface are reduced to metal atoms, so that these metal atoms deposit and crystallize to form a coating, that is, the required uniform deposition layer is obtained on the working surface of the cavity of the repaired plastic mold.
Laser welding is a welding that uses a laser beam focused by high-power coherent monochromatic photon flow as a heat source. This welding method usually includes continuous power laser welding and pulsed power laser welding. The advantage of laser welding is that it does not need to be carried out in a vacuum, but the disadvantage is that the penetration is not as strong as electron beam welding. Laser welding can carry out precise energy control, so it can realize the welding of precision devices. It can be applied to many metals, especially the welding of some difficult-to-weld metals and dissimilar metals. At present, it has been widely used in the repair of molds.
Light welding is to use a high-power coherent monochromatic photon flow focused laser beam as a heat source for welding. This welding method usually includes continuous power laser welding and pulsed power laser welding. The advantage of laser welding is that it does not need to be carried out in a vacuum, but the disadvantage is that the penetration is not as strong as electron beam welding. Laser welding can carry out precise energy control, so it can realize the welding of precision devices. It can be used for many metals, especially the welding of some difficult-to-weld metals and dissimilar metals. At present, it has been widely used in the repair of molds.