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Transporting cylinder chromium plating process the chromium plating layer density reached 300 mesh/was, surface hardness above HV900, generally chromium plating process of chromium plating layer for 60 mesh/was density, thickness of HV700. The company material cylinder thickness of 0.25 mm to 0.32 mm, coating adhesion is extremely strong, not easy to fall off. Fundamentally guarantee the interests of customers, improve the efficient use of the customer.