PVC injection molding plastic resin -2
1.Pay attention to the following points during product design and mold design:
Try to avoid sharp corners or abrupt changes in the product, and the thickness should not change too much, so as to prevent the PVC from degrading.
2.The mold should be designed with a draft angle of more than 10°, allowing for a shrinkage rate of about 0.5%.
3.During mold runner design, pay attention to the following points
a). The mold injection gate should be slightly larger than the nozzle, and larger than the diameter of the conjunctions in the sprue, so that the PVC material is able to flow into the cavity without being blocked, while the pressure is also balanced.
b). Try to adopt the intercepting gate, so that the slag will not flow into the product and cause runner temperature reduction, thus making it easier to form.
c). The gate should be designed at the thickest part of the product, with a sufficient width guaranteed, while the length is preferably between 6-8mm, so that the PVC material is able to flow in smoothly.
d). To reduce pressure and facilitate ejection, a circular runner is preferred, with the diameter ranging from 6 to 10mm, depending on the size and weight of the product.
4. The mold temperature should be controlled by a cooling device, to keep the temperature controllable between 30°C and 60°C.
5.The mold surface should be smooth and chrome-plated to prevent corrosion.
PVC injection molding process
With regard to the injection molding process, pay attention to the following:
(To be continued...)