The molding process of tarpaulin is an important step in making tarpaulin. Linyi tarpaulin manufacturers will talk about the molding process of tarpaulin.
1. Feeding: add a certain amount of material to the mold as needed, and the amount of feeding directly affects the density and size of the product.
If the feeding amount is large, the product has thick burrs, poor dimensional accuracy, difficulty in demoulding, and may damage the mold;
If the amount of feed is small, the product is not tight, the gloss is poor, and even the waste is produced due to lack of material.
2. Closing die: even if the positive die and the negative die are closed after feeding.
When the mold is closed, use it quickly, wait for the Yin, and change to slow when the Yang mold is in contact.
The quick and slow operation method is conducive to shortening the non-production time, preventing the mold from scratching, avoiding the raw materials in the mold groove being taken out by the air due to too fast clamping, and even shifting the insert and damaging the molding rod.
When the mold is closed, the pressure can be increased to heat and pressurize the raw material.
3. Exhaust: When molding thermosetting plastics, moisture and low molecules are often released. In order to eliminate these low molecules, volatile substances and in-mold air, etc, after the plastic reaction in the mold cavity of the plastic mold is carried out to an appropriate time, the release of the release mold can be discharged for a short time.
The exhaust operation can shorten the curing time and improve the physical and mechanical properties of the product, avoiding delamination and bubbles inside the product;
But the exhaust is too early, sooner or later, and it is too early to achieve the purpose of gas;
If it is too late, the solidified gas on the material surface will not be discharged.
The above is the process flow and precautions of the tarpaulin molding process. If there are other problems, please feel free to contact us and look forward to your call!