Heat Treatment Technology and Finishing of Sprocket Gears

Heat treatment process

The heat treatment of the sprocket gear directly determines the inherent quality of the gear teeth. Tooth profile processing and finishing after heat treatment are the key to manufacturing, and also reflect the level of gear manufacturing.The quality of the heat treatment process will directly affect the strength, precision, noise and life of the gear.


The working conditions of the sprocket gear are different, and the damage form of the gear teeth is different, which is the basis for determining the calculation criteria of the gear strength and selecting the material and heat treatment.At present, the gear finishing methods used in industry are mainly shaving, grinding, extrusion, grinding and honing.

Teeth shaving is shaving with a razor on a shaving machine.It drives the processed gears to rotate relative to each other, relying on the relative sliding of the tooth surfaces, the shaving cutter cuts off a thin layer of metal on the tooth surfaces to complete the finishing of the gears.The production efficiency of tooth shaving is high, and it is suitable for finishing the soft tooth surface after hobbing and tooth shaping.

Tooth grinding is to use a grinding wheel to grind the tooth surface. Grinding can grind gears with hardened tooth surfaces, eliminate heat treatment deformation and improve gear accuracy.According to the different grinding wheels used, they are divided into:

(1) Conical grinding wheel grinding teeth;

(2) Butterfly grinding wheel grinding;

(3) Grinding teeth with large plane grinding wheel;

(4) worm grinding wheel grinding;

(5) Grinding of involute envelope toroidal worm grinding wheel;

(6) Forming grinding wheel to grind teeth.

Tooth extrusion is to use the extrusion wheel to extrude the tooth surface of the processed gear to improve the surface quality of the gear.

The honing method is basically the same as the shaving method, that is, the shaving cutter is replaced with a honing wheel of the same shape, and the tooth surface is polished by relative sliding with the tooth surface, and the tooth surface of the processed gear can be soft or hard.