Key points of plastic profile extrusion molding process Plastic sheet production line
DATE：2021/2/27 11:36:14 / READ： / SOURCE：This station
Key points of plastic profile extrusion molding process
Plastic sheet production line
Extrusion molding is one of the main molding methods for plastic products, and is currently widely used in construction, electrical appliances, lighting and other fields. Plastic extrusion molding is to extrude the molten plastic through an open die under pressure to obtain a continuous plastic product with a cross-section similar to the shape of the die hole. Through the method of extrusion molding, many different types of plastic products can be obtained, such as plates, pipes, profiles, films, rods and fibers. The following describes the key points that need to be paid attention to in four-point extrusion molding and mold design in combination with practical applications:1. According to the type of product structure, select the extrusion molding method. The general shaping methods are mainly air-cooled and water-cooled. Generally, the thicker profile of the open type adopts the air-cooled shaping mold, and there is no shaping sleeve. The outer contour of the product is directly shaped by the open copper sheet. The advantage is that it helps to improve the surface drawing. The problem and product details are more adjustable in the shape of the card position; the closed structure product is shaped by a water-cooled shaping sleeve to ensure the appearance of the product. The advantage is that the extrusion speed is fast. Plastic sheet production line www.handern.com
2. Selection of extrusion product materials. For high optical requirements, PC materials with high luminous efficiency can be selected. For bracket products, ABS and PVC materials can be selected for cost factors. There are also some line lights and PMMA materials with better light transmission requirements. For different materials, you need to choose the appropriate processing temperature and baking temperature.
3. According to the product structure and material characteristics, select the appropriate mold design plan. For some products with simple structure, try to give priority to the use of more than one mold solution, which is conducive to improving processing efficiency. Because the PC material is more viscous, when it is applied to LED lighting products, only some simple tubular structures are suitable for 1 out of 2 or 1 out of 4 extrusion molds. When the product structure is complex, only 1 out of 1 molds can be used. forming. The processing stability of PVC and ABS materials is better, and the dimensional stability of the formed products is better. Generally, the direct baking material is preferably used in the extrusion die method of more than one. Plastic sheet production line www.handern.com
4. Combining the feasibility of actual process and mold processing, the product appearance design needs to be more reasonable. First, the product wall thickness is designed to be as uniform as possible, and the wall thickness difference is too large, which will easily lead to excessive internal stress in the product extrusion. Generally, it is recommended that the wall thickness design difference should not exceed 1.3 times. Second, the corner position of the product needs to be designed with rounded corners to ensure that the inner and outer corners are as concentric as possible. Generally, the rounded corners should be designed to be R0.2mm. Too small, too small will easily lead to excessive local stress of the product. Third, the inner rib design of the product should not be too thick or too long. Generally, the thickness of the inner rib is thinner than the thickness of the outer wall, which is conducive to rapid cooling during forming; the length of the rib should not exceed the wall thickness by 2 times.
The birth of a perfect product is inseparable from the structural design of the product itself, as well as the molding process and mold design. Only these mutual matching can ensure the mass production of a product and ensure that the product has strong cost competitiveness. Plastic sheet production line www.handern.com
Author：admin