Specific reasons for cracking of injection molded parts.

Injection molding, also known as injection molding, is a processing method in which molten plastic is injected into a mold under high pressure and then cooled and solidified in the mold to finally form the required plastic product. Injection molding is widely used in the production of plastic products of various sizes and shapes, such as daily necessities, industrial parts, automotive parts, etc.

The main steps of injection molding include:

Feeding: Put solid plastic particles or powder into the hopper of the injection molding machine, and melt it into a flowing molten plastic through heating and stirring.

Injection: The molten plastic is pushed by the screw of the injection molding machine and injected into the cavity of the mold under high pressure to fill the entire mold cavity.

Cooling: The molten plastic injected into the mold cools and solidifies in the mold to form the required product shape.

Mold opening: After the plastic cools and solidifies, open the mold and take out the molded plastic product.

Injection molding has many advantages, such as:

High precision: Injection molding can produce parts and products with high precision and high consistency.

High production efficiency: Injection molding machines can produce a large number of products in a short time and are suitable for mass production.

Stable product quality: Since injection molding can control every production parameter well, the product quality is very stable.

Strong plasticity: Injection molding is suitable for various types of plastics and can produce products of various complex shapes.

During the injection molding process, product cracking is usually caused by the following reasons:

Material selection: Choosing materials that are not suitable for injection molding or materials with substandard quality can lead to product cracking.

Temperature control: Injection molding requires strict control of the temperature during the heating and cooling processes. If the temperature is not controlled properly, it is easy to cause excessive internal stress in the product and cracking.

Pressure problem: Improper pressure control during the injection molding process, especially in the injection and holding pressure stages, can lead to uneven product structure or excessive internal stress and cracking.

Mold design: Unreasonable mold design or problems with manufacturing quality can also lead to product cracking.

Product design: Unreasonable product structure design, uneven wall thickness or the presence of stress concentration areas can also lead to cracking problems of products during the injection molding process or in use.

To avoid product cracking, comprehensive analysis and optimization need to be carried out in aspects such as material selection, production process, mold design and product design.