1. Material: 38 CrMoAl A

Nitriding treatment,Surface hardness :HV≧900

Nitriding depth:0.5-0.8mm

2.Material:Special stainless still

Quenching treatment,hardness:HRC55-58

Suitable for the screw which used for transparent plastic products and high corrosion plastic, prolong life of screw.

3.Material :Tungsten alloy.

Surface spraying ,improve abrasion performance of screw