The substrate 38crMoAIA screw surface using double alloy welding, can effectively improve the...
Base material:38CrMoAlA, spiral angular surface using double alloy imported alloy steel, after...
Φ45/90 Φ45/100 Φ50/105 Φ51/105 Φ55/110 Φ60/125 Φ65/120 Φ65/132 Φ68/143 Φ70/140 Φ7...
Diamater:Ф16-Ф300
L:D ratio:L/D=15-40
There are gradual , saltain, wave, screen, ...