How To Design A Suitable Draft Angle Of Plastic Product?

In order to facilitate good demoulding for plastic injection molds, the wall of the plastic part should have a tilt Angle α in the direction of the exit mold, and its value is expressed in degrees.

(1) The higher the accuracy of the product, the smaller the inclination of the drawing die should be.

(2) For products with large size, a smaller drawing inclination should be used.

(3) If the shape of the product is complex and not easy to draw, a larger slope should be selected.

(4) The shrinkage rate of the product is large, and the slope should also be increased.

(5) Reinforced plastics should be selected with a large slope, and plastics containing self-lubricants can be used with a small slope.

(6) The wall thickness of the product is large, and the slope should also be large.

（7）The direction of the slope. The inner hole shall be subject to the small end, meet the size requirements of the drawing, and the slope shall be obtained in the direction of expansion; The shape is based on the big end, which meets the requirements of the pattern, and the slope is obtained in the direction of the smaller. In general, die slope. Not limited by the product tolerance zone, the die slope of high-precision plastic parts should be within the tolerance zone.

 

The plastic is hard and brittle, the rigidity is large, and the inclination of the drawing die is large. The core with the following conditions can use a smaller drawing slope:

 

(1) The product stiffness is sufficient when ejecting.

(2) The friction coefficient between the product and the die steel surface is low.

(3) The roughness value of the core surface is small, and the polishing direction is consistent with the direction of the drawing of the product.

(4) The product has small shrinkage and small sliding friction.