Standard Specifications | 45/90, 51/105, 55/110, 65/132, 80/156, 80/172, 92/188 | Advantages | 1.Advanced Nitriding Technology 2.Anti-corrosion and Wear-resisting Duplex Metal Spraying Technoloy 3. we uses special alloy powders being sprayed and welded on the screw's ridge,and uses different alloy and welding methods for the screw of different functions. |