Screw and barrel for extruder
![](http://www.jwell.cn/cn/product/images/p10-1.jpg)
1) 38CrMoAlA(JIS SACM645)
2) 42CrMo(JIS SCM440)
1) 38CrMoAlA(JIS SACM645)
2) 42CrMo(JIS SCM440)
Heat-treatment
Nitriding treatment
Electroplated hard-chrome finish
High frequency quenching
Spray bimetallic coating
Vacuum quenching