Auxiliary machine Auxiliary machine for plastic mesh extrusion molding
DATE：2022/11/2 8:40:09 / READ： / SOURCE：This station
Auxiliary machine Auxiliary machine for plastic mesh extrusion molding
It is basically similar to the auxiliary machine used in the production of monofilament and flat strip, but also has cooling water tank, stretching heating device and coiling device for products. The difference between the auxiliary machine for plastic mesh production and the auxiliary machine for plastic monofilament and flat strip production is that when the round mesh forming mold is used, there is a stretching cylinder connected with the mold through a screw rod within 60~120mm from the forming mold (Figure 10-2). The purpose of this drawing cylinder is to stretch and cool the screen blank extruded from the die. If you want to get a different distance from the mold, you can adjust it by connecting the screw rod; If you want to produce wire mesh with different diameters and get different sizes of screen products, you can replace the stretching cylinder with corresponding specifications.If the flat wire mesh forming die (Figure 10-3) is used for production, the auxiliary machine shall have a traction roller with a similar calendering structure. The wire mesh blank extruded from the die shall first pass through the air cooling temperature and then enter the drafting roller.
See Table 10-1 for technical parameters of auxiliary machine for plastic screen extrusion molding. This auxiliary machine is produced by Shandong Rubber Machinery General Factory.
Forming process
① Process conditions of plastic screen extrusion: The process temperature of each section of the extruder barrel is controlled by domestic HDPE 5000S resin as follows: 140~170 ℃ for the feeding section, 180~200 ℃ for the plasticizing section, and 200~210 ℃ for the homogenizing section.
② When using domestic HDPE and LDPE resin mixture (50% each), the process temperature of each section of the barrel is: 120~160 ℃ for the feeding section, 170~190 ℃ for the plasticizing section, and 200~220 ℃ for the homogenizing section.
③ The mold temperature is 230~250 ℃.
④ The water temperature in the cooling water tank is about 40 ℃. The drawing diameter shall be controlled within 1~3 times of the die diameter.
⑤ If the wire mesh needs to be stretched, the water temperature in the stretching hot water tank is about 100 ℃, and the stretching ratio of the wire mesh is controlled within the range of 4-6 times.
Key points of process operation
① When the mold rotation speed is equal to the traction wire mesh speed, the inner and outer molds rotate at the same time, and the wire mesh is diamond shaped; If the internal mold or external mold is rotated separately, the wire mesh will be square.
② When the traction speed is greater than the mold rotation speed, the internal and external molds rotate at the same time.
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