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Location: 5F, Torch Building, No. 54 Metallurgical Avenue, Qingshan District, Wuhan, Hubei Province

Phone: 027-8656 3216

Email: sales.information@baierchina.


How to distinguish the quality of the sleeve




Surface treatment of sleeve

(1) Bright chrome: very bright like a mirror

(2) Chromite: Matt

(3) Electrophoresis: black with brightness. Under the action of an external DC power supply, the charged particles are directed to the cathode or anode in a dispersed medium to promote the separation of substances;

(4) Phosphating: black, but matte. The sleeve is immersed in a phosphating solution, and a layer of water-insoluble crystalline phosphorus is deposited on the surface, which is the conversion process of phosphate.

Manufacturing process of Bayer company sleeve

Blanks (with various specifications)-grinding (removing burrs, etc.)-turning (mainly molding)-grinding the surface-engraving (such as knurling, printing LOGO, etc.)-heat treatment (in order to increase its hardness )-Electroplating (nickel plating or chromium etc.)-Grabbing black etc.

(1) Look at the surface: whether there are burrs, whether the specifications meet the size standards, whether there are scratches, etc.

(2) Inner substance: measure the torque and hardness with special tools; measure the size; salt spray test etc. Note: When the size of the hexagonal or twelve corners of the socket wrench is less than or equal to 32MM, the hardness value is not lower than HRC39 When it is larger than 32MM, the hardness is not lower than HRC35.