45# steel Hard Chrome Plated Piston Rod with mirror polishing for gas & oil cylinders

The surface of the products are grand with a special way and electroplated with hard chrome. Finished with mirror polishing, the product is endurable and anti-corrosion, can apply to various gas & oil cylinders, piston rods, packing, carpentry, textile,  printing and dyeing machines, die casting machines, injection molding machines, other mechanical guide rods and carrier rods, etc.

1 material :  top 45# steel

2 outer diameter tolerance : f7-f8 ( with other tolerances available)

3 surface roughness : Ra0.2-0.4

4 hard chrome thickness :  0.015-0.025mm

5 surface hardness : HV700-1150

6 straightness : 0.05-0.10m/m

7 standard length : 1-6 m

Note : those whose surface need to be high echoed with depth 1-3 mm and thickness HRC4552 can be customized. The thickness of plated chrome are vary according to applications : gas hydraulic = =0.02 mm , oil hydraulic is above 0.02 mm.

Process specification:

Chromic anhydride : 250-300g/l 

Best value : 280

Sulphuric acid : 1.8-2.5g/l

Trivalent chromium : 2.5-5g/l

Additive A(DW-032A):10-20ml/l  

Additive B(DW-032B):10g/l 

Fluorine free anti-fog agent C( DW-026): 0.05~0.15ml/l

Temperature : 45-59° note that the temperature is not too high

Current density : 35-90A/dm2

Current efficiency : 30-35

KAF consumption  :  A  50ml/l  B 0.25- 0.5g/l  Fluorine free anti-fog agent C 0.01ml/l 

100kg Chromic anhydride need to be fixed with  A  3-5kg, B 0.5- 1kg  C100ml