durable high quality excavator parts hydraulic lift cylinder assembly

Material 

45# high     grade carbon steel or 40CR

Tempering hardness 

HB240-260

The depth of the high frequency

2mm-3mm

High frequency hardness

HRC55°±2°

Chrome plating thickness

0.03mm-0.06mm

Chromium layer hardness

HV800-1000vpn

Straightness 

≤0.08mm/m

Surface roughness

Ra0.03um- Ra0.06um

Outside diameter tolerance

f7

Kind of steel 

45#

Tensile strength N/mm

≥647

Linearity 

0.3-1/1000 

Specific elongation

≥4

Precision of size

HB

207

Roughness of inner hole

0.4-0.8