Advantages of power honing for gear processing

Why does gear need honing?

After quenching, the gear teeth have oxide scale on their surface, which affects the roughness of the tooth surface. The deformation caused by heat treatment also affects the accuracy of the gear. Since the workpiece has been hardened, in addition to grinding, honing can also be used for finishing.

The principle of honing is similar to that of shaving. The honing ring and the workpiece are similar to a pair of helical gears meshing without side clearance. The relative sliding of the meshing part and a certain pressure between the tooth surfaces are used for honing.

The movement during honing is the same as that of shaving. The honing wheel drives the workpiece to rotate forward and reverse at high speed, and the workpiece reciprocates along the axial direction and is fed radially. Unlike shaving, the radial feed is fed to the predetermined position once after starting, so the tooth surface pressure is large at the beginning, and then gradually decreases until the pressure disappears, and the honing ends.

The honing ring is cast on the iron core after mixing abrasives (usually corundum with a particle size of 80#~180#) and raw materials such as epoxy resin. Honing is a finishing method after the heat treatment of gears.

In modern automobile processing and production, the transmission surface accuracy of gears is very high. The honing technology ensures the high quality of gears and can reduce the noise and wear of parts of the gearbox.

Power honing is a honing process for finishing the gear surface after the gear is heat treated. It is achieved by dressing the dressing wheel, the workpiece shaft and the honing wheel shaft undergo complex movements, and honing removes a certain amount of excess on the gear surface. The gear accuracy can be improved by 2-3 DIN levels.

The honing process is regarded as an important process for significantly reducing gear noise. The tooth surface after honing has been proven to have a better noise reduction effect than after grinding, because the tooth surface corrugation after honing has its special mesh texture. The honing process is also considered to be particularly suitable for the post-heat hard processing of two adjacent gears, because it requires much less undercut grooves between the two gears than grinding.

The principle of honing is similar to that of shaving. The honing ring and the workpiece are similar to a pair of helical gears meshing without side clearance. The relative sliding of the meshing part and a certain pressure between the tooth surfaces are used for honing. The movement during honing is the same as that of shaving. That is, the honing ring drives the workpiece to rotate forward and reverse at high speed, and the workpiece reciprocates along the axial direction and the workpiece is fed radially. Unlike shaving, the radial feed is fed to the predetermined position at one time, so the tooth surface pressure is large at the beginning, and then gradually decreases until the honing ends when the pressure disappears.

Powerful honing grinding is a tooth surface finishing method that uses a gear-shaped honing ring to mesh with the honed gear, which is equivalent to a pair of staggered axis helical gear transmission and uses the relative sliding speed and pressure between the tooth surfaces to perform honing. At the same time, powerful honing is a tooth surface finishing method that directly uses the honing method after heat treatment to remove a certain processing allowance, which can correct the error of the honed gear.

Powerful honing has six major advantages:
1. Honing arcs can reduce the vibration noise of gears
During honing, the honing wheel and the gear are in a staggered axis meshing state, and the relative sliding along the tooth shape direction and the relative sliding along the tooth width direction form a unique honing arc, which can greatly reduce the gear transmission noise.
2. Higher surface compressive stress can be obtained
Honing can produce higher residual compressive stress (1000-1600N/mm2) on the tooth surface, effectively improving the strength, wear resistance and pitting resistance of the gear.
3. Avoid tooth surface burns
Grinding burns have always been a major problem in the grinding process, and grinding heat will reduce the life of the gear. Powerful honing removes material through relative sliding of the tooth surface, with a low cutting speed, and will not produce high-temperature effects on the tooth surface, avoiding tooth surface burns.
4. Better tooth surface roughness
Honing can obtain a smaller tooth surface roughness value at a more economical cost, Ra＜0.1 μm.
5. Can process gears with shoulders
The profile grinding of small grinding wheels is difficult to meet the processing requirements of gears with other interference structures and empty grooves. However, the strong honing process can achieve this. Since the contact method is line contact, honing can be performed along the axial direction of the workpiece to complete the processing of the entire tooth surface, and a more compact gear with shoulders can be obtained.
6. Reduce tool costs
Strong honing can achieve precision machining of gears more economically, with high output, high precision and low unit cost.

MORESUPERHARD’s honing ring can improve the surface roughness of the gear, improve the tooth surface finish, and ensure the accuracy of the gear shape. The tooth surface shape is formed by grinding the tooth shape inside the gear honing wheel, which can reduce the noise of the gear.

Advantages of gear power honing grinding wheel

1. Compared with traditional gear grinding, gear power honing can effectively improve the quality of tooth surface machining
2. Gear power honing technology has uniform cutting force, high machining accuracy and stability
3. Gear power honing can effectively improve the strength, wear resistance and pitting resistance of gears.
4. Gear power honing can reduce the burn on the tooth surface
5. Gear power honing has high production efficiency and low cost, which can realize mass production of gear precision machining more economically and reduce production costs.

—EDITOR: Doris Hu, Sarah Shi

—POST: Doris Hu