Pin point gate, also called olive shaped gate or diamond shaped gate, is a section of circular cross section gate size too small, is the application of a very wide range of gate. Pin point gate size is very important, if the gate opening is too large, in part, the gate of plastic can be difficult to pull off, but, by the gate of plastic products of tension, the stress will affect the shape of plastic parts. In addition, if the pin point gate taper is too small, open mold, pouring plastic where breaking is difficult to determine, will make the product look bad. The runner diameter is 0.6-2.8mm, length is 0.7-1.5mm.
  1.Advantages of point gate. Pin point gate location choice according to the technique request, has little effect on the appearance quality of the products; melt through cross-sectional area is very small gate when the flow rate increased, increased friction, the flow of melt temperature, temperature increase, so, can obtain the contour clear, surface gloss of plastic parts; the gate area is small, the mold when the gate can be automatically broken, is conducive to the automatic operation; because the gate rupture force in small, therefore, the residual stress in the gate of products smaller; the gate solidification faster, can reduce the stress in mold surplus, to release the products.
  2.point gate defects. The pressure loss of large, adverse to the molding, also requires a higher injection pressure; die structure is relatively complex, in general to the mold, to release, but can still use the two plate mould in runnerless die; because the sprue flow rate is high, cause the molecular highly directional, increase the local stress, prone to cracking phenomenon; for large plastic parts or easy plastic deformation, using a pin point gate is easy to deform, then, can develop several point gate feeding at same time.
  3.Application of point gate. Pin point gate is suitable for low viscosity and viscosity on the shear rate sensitive plastic plastic, such as PE, PP, PA, PS injection molding, ABS, suitable for multi cavity mold center feed.