Principle of mold design(2)


Release time :

2023-03-22

In the last issue, I introduced the first part of the principle of mold design, and today I will continue to introduce the second part of the principle of mold design. 1. The surface of the plastic part. In terms of the range that the molding material can cover, the surface structure of the visible surface of the plastic part should be formed at the contact with the mold. If possible, the smooth side of the plastic part should not come into contact with the mold surface. As is the case with bathtubs and laundry tubs using female molds. 2. To modify, if a mechanical horizontal saw is used to cut off the clamping edge of the plastic part, there must be at least 6-8mm margin in the height direction. Additional finishing work, such as grinding, laser cutting or jetting, must also have allowances. The gap between the cutting lines of the knife die is the smallest, and the distribution width of the punching die is also very small when trimming. These are all things to pay attention to. 3. Shrinkage and deformation. Plastics are easy to shrink (such as PE), and some plastic parts are easy to deform. No matter how to prevent them, plastic parts will deform during the cooling stage. Under such conditions, it is necessary to change the shape of the molding die to adapt to the geometric deviation of the plastic part. For example: Although the wall of the plastic part remains straight, its reference center has deviated by 10mm. The mold base can be raised to adjust the amount of shrinkage for this deformation. 4. Shrinkage, the following shrinkage factors must be taken into account when manufacturing blister molding molds. ① The molded product shrinks. If the shrinkage rate of the plastic cannot be clearly known, it must be obtained by sampling or testing with a mold of a similar shape. Note: Only the shrinkage rate can be obtained by this method, and the deformed size cannot be obtained. ② Shrinkage caused by adverse effects of intermediate media, such as ceramics, silicone rubber, etc. ③ Shrinkage of the material used in the mold, such as shrinkage when casting aluminum. All the principles of mold design have been explained for everyone. If you have any questions, you can leave me a message or pay attention to us. We are a professional manufacturer integrating production and sales. Tomorrow, I will introduce to you the working principle of the daily chemical pump head.

In the last issue, I introduced the first part of the principle of mold design, and today I will continue to introduce the second part of the principle of mold design.

1. The surface of the plastic part. In terms of the range that the molding material can cover, the surface structure of the visible surface of the plastic part should be formed at the contact with the mold. If possible, the smooth side of the plastic part should not come into contact with the mold surface. As is the case with bathtubs and laundry tubs using female molds.

2. To modify, if a mechanical horizontal saw is used to cut off the clamping edge of the plastic part, there must be at least 6-8mm margin in the height direction. Additional finishing work, such as grinding, laser cutting or jetting, must also have allowances. The gap between the cutting lines of the knife die is the smallest, and the distribution width of the punching die is also very small when trimming. These are all things to pay attention to.

3. Shrinkage and deformation. Plastics are easy to shrink (such as PE), and some plastic parts are easy to deform. No matter how to prevent them, plastic parts will deform during the cooling stage. Under such conditions, it is necessary to change the shape of the molding die to adapt to the geometric deviation of the plastic part. For example: Although the wall of the plastic part remains straight, its reference center has deviated by 10mm. The mold base can be raised to adjust the amount of shrinkage for this deformation.

4. Shrinkage, the following shrinkage factors must be taken into account when manufacturing blister molding molds. The molded product shrinks. If the shrinkage rate of the plastic cannot be clearly known, it must be obtained by sampling or testing with a mold of a similar shape. Note: Only the shrinkage rate can be obtained by this method, and the deformed size cannot be obtained. Shrinkage caused by adverse effects of intermediate media, such as ceramics, silicone rubber, etc. Shrinkage of the material used in the mold, such as shrinkage when casting aluminum.

All the principles of mold design have been explained for everyone. If you have any questions, you can leave me a message or pay attention to us. We are a professional manufacturer integrating production and sales. Tomorrow, I will introduce to you the working principle of the daily chemical pump head.