Bevel gear made of brass Ms58 module 0.5 15 teeth i=1:1 milled PN: 35020600

The worms are made of case hardened steel with ground bore and worm profile. The worm gears are made of a special alloy (copper-zinc alloy with additives of aluminum, silicon and manganese). It is treated for better sliding characteristics. The chemical resistance is very high due to aluminum additives.

Brass worm gears

The worm wheels are made of a special alloy (copper-zinc alloy) with additives of aluminum, silicon and manganese. It is a special quality developed for sliding purposes.
The chemical resistance is very high due to the aluminum content.
Worm gears made of brass have good corrosion resistance, high strength, good sliding properties and high wear resistance.

Note:

The lead content in worms and worm wheels made of brass is ≤0.1 percent by weight

Plastic worm gears

Plastic worm gears are suitable for low sliding speeds (< 1.5 m/s) and medium tooth pressure due to their bad thermal conductivity. Worms have to be hardened and ground.
The thermal expansion coefficient is appr. 4 times higher than with brass. Therefore the backlash shouldn’t be too small.

Bronze worm gears

Cu Sn 12 DIN EN 1982
Comparatively soft material with good wear resistance, suitable for high sliding speeds.

Cu Sn 12 Ni DIN EN 1982
Comparatively soft material with very good wear resistance, suitable for very high sliding speeds.

CuAl10Fe5Ni5 DIN EN 1982
Comparatively hard material for high torque and low speed.

Cast iron worm wheels

EN-GJS-400-15 DIN EN 1563 / EN-GJL-250 DIN EN 1561
Only suitable for low planing speeds.

Self-locking is affected by the lead angle, the roughness of the flanks, the sliding speed, the lubricant and increases in temperature. Self-locking can be dynamic or static.

Dynamic self-locking: lead angle up to 3° with grease lubricant; lead angle up to 2.5° with synthetic oil lubricants.
Static self-locking: lead angle from 3° to 5° with grease lubricant; lead angle from 2.5° to 4.5° with synthetic oil lubricants.
No self-locking facility is available for lead angles over 4.5° or 5°.

Jarring and vibration can prevent gears from self-locking. Self-locking can also be adversely affected if sliding conditions are particularly good. This can be caused by a number of factors relating to the lubricant, sliding speed and loading. For this reason we are unable to assume any warranty obligations for self-locking.

The reference surface tolerances will determine the lateral positioning of the worm gears. The lateral tolerance “c” must not exceed 0.15 mm for any centre distance.

You can tell if the worm gear is in the correct axial position by checking the position of the tooth contact pattern when the gear wheel is installed. If possible the tooth contact pattern should be towards the run-out side. When the gear is turned in the other direction (reverse operation) the tooth contact pattern should be towards the centre.

The efficiency of the worm gear set generally depends on the following parameters:

• Lead angle of the worm
• Sliding speed
• Lubricant
• Surface quality
• Installation conditions

The larger the centre distance, the greater the degree of efficiency. Sliding bearings are often used with gears with smaller centre distances to save space and reduce costs. The sliding bearings have higher coefficients of friction, which can have a considerable effect on the overall efficiency of the gear. Efficiency data can be obtained from the manufacturer or our catalogue.

The information on this website was generated with the greatest possible care and checked for accuracy. No liability will be accepted for any inaccurate or incomplete data.