Plastic mold planning is based on correct plastic product planning. Mold planning and manufacturing are closely related to plastic processing. The success of plastics processing largely depends on the role of mold planning and the quality of mold manufacturing.The structural factors that come to mind when planning for plastic molds include:
1. Parting surface, that is, the contact appearance of the concave mold and the convex mold when the mold is closed. The choice of its orientation and method is affected by factors such as the shape and appearance of the product, wall thickness, molding method, post-processing technology, mold type and structure, demolding method, and molding machine structure.
2. Structural parts, that is, sliders, inclined tops, and straight top blocks of complex molds. The planning of structural parts is very important, which is related to the life of the mold, the processing cycle, the cost, the product quality, etc. Therefore, planning a complex mold center structure requires higher comprehensive ability of the planner. Proposal.
The size of the plastic part is small, and the precision level of the product is low. It requires good performance, no cracks, bending resistance, and large-scale production. The mold is planned into a mold and eight-cavity structure, and the following problems are solved.
First, the balance of the pouring system. Multi-cavity molds should be designed so that all cavities are fed at the same time as possible. Because the number of cavities increases, the length of the manifold must be increased. Before the melt reaches the cavity, the injection pressure is increased. There will be a large loss of the heat of the melt. If the flow path is slightly unreasonable, the plastic parts may have disadvantages, such as one-cavity or several-cavity dissatisfaction, or immediate full, but there are problems such as poor welding or internal arrangements. Looseness and other shortcomings, such as raising the injection pressure, and flashing easily occur. The method of planning the runners in the paper uses an unbalanced layout method. After setting the size of the gate and the runners, the injection process is adjusted to a value to ensure that the cavity shrinkage is common, and the plastic parts with high accuracy requirements are guaranteed to be interchanged. The orientation of the gate is set at the thick end of the plastic part as the Y end, which is conducive to movement and shrinkage. It can also prevent welding marks from occurring. The molecules have the orientation to reach the requirement of bending without cracking.
2. Cooling system planning The principle of planning the cooling device is to plan the cooling device without increasing the foundation of the mold's own structure. The number of cooling circuits should be as large as possible on the premise that the transfer area required for cooling and the mold structure allow it. Multi-planning, and the diameter of the cooling channel is as large as possible. Cooling water holes are processed on the upper and lower cavity plates and the movable fixed template. The cooling water holes of the upper cavity plate are connected with the water holes of the fixed template during installation, and then sealed with a sealing ring. The cooling water hole of the lower cavity plate is connected with the water hole of the movable template, and it is also sealed with a seal ring. The water holes are arranged on the upper and lower cavity plates and the movable fixed template.