In the production process of plastic pipes, the parting surface design of plastic pipe mold is an extremely critical link. It not only affects the structural complexity and processing difficulty of the mold, but is also directly related to the convenience of pipe demoulding, which in turn plays an important role in production efficiency and product quality. Reasonable design of the parting surface can ensure that the pipe is smoothly separated from the mold after forming, reducing demoulding resistance and possible damage.
The parting surface should be selected along the largest contour line of the plastic product, so that the plastic product can smoothly come out of the mold cavity when the mold is opened. At the same time, the processing technology of the mold should be taken into consideration, and the parting surface should be as simple and regular as possible to avoid complex curved surfaces or fold lines to reduce the difficulty and cost of mold manufacturing. For example, for circular plastic pipes, a plane along the diameter of the pipe can usually be selected as the parting surface.
The position and shape of the parting surface will significantly affect the demoulding resistance of the pipe. If the parting surface design is unreasonable, such as an undercut or step structure, greater friction and holding force will be generated during demoulding, which will increase the difficulty of demoulding and may even cause the pipe to be deformed or damaged. By optimizing the parting surface so that it is consistent with the demoulding direction of the pipe, demoulding resistance can be effectively reduced and smooth demoulding achieved.
A suitable demoulding mechanism needs to cooperate with the parting surface to better realize pipe demoulding. For example, when using ejector pins to demould, the parting surface should reserve the installation position of the ejector pins, and the distribution of the ejector pins should be even and reasonable to ensure balanced force when the pipe is ejected. When the parting surface has a certain inclination, the design of the demoulding mechanism must also be adjusted accordingly to adapt to the demoulding motion trajectory of the pipe.
The parting surface is also closely related to the exhaust effect of the plastic pipe mold. Good exhaust helps reduce the pressure of the plastic melt in the mold cavity, thereby reducing the holding force on the pipe and indirectly improving the ease of demoulding. Setting an exhaust groove at the parting surface or using the gap of the parting surface for exhaust can effectively remove the air and volatile gases in the cavity, making the pipe forming smoother and demolding easier.
Different plastic materials have different properties such as shrinkage, viscosity and rigidity, which will also affect parting surface design and ease of demoulding. For example, plastics with a large shrinkage rate have a greater force to hold the mold during the cooling process. When designing the parting surface, a certain demoulding slope must be considered to compensate for the impact of shrinkage and prevent the pipe from being damaged during demoulding. strain.
The parting surface design of plastic pipe mold has a decisive impact on the convenience of pipe demoulding. During the design process, it is necessary to follow relevant principles, fully consider the impact of the position and shape of the parting surface on the demoulding resistance, ensure good cooperation with the demoulding mechanism, take into account the exhaust requirements, and optimize and adjust based on the characteristics of the plastic material. Only in this way can a reasonable parting surface be designed to improve the convenience of pipe demoulding and achieve efficient and high-quality plastic pipe production.
