Paint Pail Mould Suppliers introduced that shrinkage in plastic processing is one of the most common problems in plastic processing. For plastic products that require high surface quality, shrinkage is even more difficult. Therefore, with the continuous improvement of plastic processing technology, in order to minimize the shrinkage of plastic processing, it is imperative to improve product quality.
In plastic processing, injection molded plastic parts are thicker, such as ribs or protrusions, that are more severely contracted than adjacent locations. This is because the cooling rate of the thicker area is much slower than that of the surrounding area. The difference in cooling rate results in the formation of depressions at the connecting surface, which are known as shrinkage marks. This defect severely restricts the design and molding of plastic products, especially large thick-walled products such as beveled cabinets and display housings for televisions. In fact, it is necessary to eliminate shrinkage marks on products with strict requirements such as household appliances, while plastic processing shrinkage marks are allowed for some products with low surface quality requirements such as toys.
There may be one or more reasons for plastic processing shrinkage marks, including processing methods, part geometry, material selection, and mold design. The geometry and material selection are usually determined by the raw material supplier and are not easy to change. However, there are still many factors related to mold design on the mold manufacturer’s side that may affect the shrinkage of plastic processing. Cooling runner design, gate type, and gate size may have multiple effects. For example, small gates such as tube gates cool much faster than tapered gates. Premature cooling at the gate will reduce the filling time in the cavity, thereby increasing the chance of shrinkage marks. For molding workers, adjusting processing conditions is a way to solve the shrinkage problem of plastic processing. Filling pressure and time significantly affect shrinkage. After the part is filled, the excess material continues to be filled into the cavity to compensate for the shrinkage of the material. Too short a filling stage will result in increased shrinkage and eventually produce more or larger shrinkage marks. This method of solving plastic processing shrinkage may not reduce the shrinkage mark to a satisfactory level, but the molding worker can adjust the filling conditions to improve the shrinkage mark.
Through the above introduction, China 20L Pail Mould Manufacturers hopes that you can simply refer to the content of this article in future use.
https://www.rixiangmould.com/
In plastic processing, injection molded plastic parts are thicker, such as ribs or protrusions, that are more severely contracted than adjacent locations. This is because the cooling rate of the thicker area is much slower than that of the surrounding area. The difference in cooling rate results in the formation of depressions at the connecting surface, which are known as shrinkage marks. This defect severely restricts the design and molding of plastic products, especially large thick-walled products such as beveled cabinets and display housings for televisions. In fact, it is necessary to eliminate shrinkage marks on products with strict requirements such as household appliances, while plastic processing shrinkage marks are allowed for some products with low surface quality requirements such as toys.
There may be one or more reasons for plastic processing shrinkage marks, including processing methods, part geometry, material selection, and mold design. The geometry and material selection are usually determined by the raw material supplier and are not easy to change. However, there are still many factors related to mold design on the mold manufacturer’s side that may affect the shrinkage of plastic processing. Cooling runner design, gate type, and gate size may have multiple effects. For example, small gates such as tube gates cool much faster than tapered gates. Premature cooling at the gate will reduce the filling time in the cavity, thereby increasing the chance of shrinkage marks. For molding workers, adjusting processing conditions is a way to solve the shrinkage problem of plastic processing. Filling pressure and time significantly affect shrinkage. After the part is filled, the excess material continues to be filled into the cavity to compensate for the shrinkage of the material. Too short a filling stage will result in increased shrinkage and eventually produce more or larger shrinkage marks. This method of solving plastic processing shrinkage may not reduce the shrinkage mark to a satisfactory level, but the molding worker can adjust the filling conditions to improve the shrinkage mark.
Through the above introduction, China 20L Pail Mould Manufacturers hopes that you can simply refer to the content of this article in future use.
https://www.rixiangmould.com/
コメント