We can supply and design all kinds of screw&barrel according to your requirement. We use Japan numerical control and computer control processing device to process screw. screw and barrel for film blowing machine have the follow specification.

1 12289 screw and barrel material
A 12289 38CrMoAlA

This kind of material is applicable to double alloy and common molding screw.

B 12289 9Gr18MoV
C 12289 42CrMo
2 12289 Technics
A 12289 Heating treatment
B 12289     Nitriding treatment
C 12289     Spray bimetallic alloy coating
3 12289 Technical parameter
A 12289 Depth of Nitration layer:0.5-0.8mm
B 12289 Hardness of Nitration :900-1000HV
C 12289 Fragility of Nitration:less than grade 1
D 12289 Roughness of the surface::Ra0.4
E 12289 Straightness of the screw:0.015mm
F 12289 Surface hardness of Nitrated Cr coating layer>=950HV
G 12289 The thickness of Chrome-plating layer:0.025-0.085mm
H 12289 Depth of alloy layer.>2mm.