The diameter from 60mm to 1500mm
The length is less than 9000mm
Weight is less than 50T
The material is 60CrMoV, H13, 80Cr2MoV, Gr15, 9Cr2Mo, 9Cr2.
Barrel hardness less than 100HSD
Making process steel ingot-forging-rough machining-QT-2th rough machining
-induction quenching-finished machining-oiling-packing-delivery