Tensile strength of LDPE resin low voltage differential, rigid poor dimensional stability when processing poor, and connection difficulties, not suitable as a water supply pressure tube material.

C9 aromatic petroleum resin was produced with pressure thermal polymerization instead of the catalytic polymerization under low temperature.

A low pressure casting equipment has been developed, which is specially designed for the production of large-size thin-walled high-quality aluminum alloy parts with resin sand molds.