Application of grease in gear box

SINBAD Micro speed motor in communication, intelligent home, automobile, medical, safety, robot and other fields are widely used, which small modulus gear drive in micro speed motor has been more and more attention and attention, and the grease used in the reduction gear box has played a boosting role, the main role of grease are: ① reduce friction and wear, prevent gluing; ② Reduce the noise; (3) Absorb shock and vibration; (4) Anti-rust and anti-corrosion; (5) Heat dissipation, cooling and removal of foreign bodies; ⑥ Improve gear meshing life, etc.

The gear material used in the reduction gear box has a great relationship with the selection of grease. Under the normal operation of the gear transmission device, the characteristics of grease should be considered: (1) with appropriate viscosity; (2) higher carrying capacity; ③ Good wear resistance; (4) Oxidation stability and thermal oxidation stability; (5) Anti-emulsification, anti-foam, anti-rust and anti-corrosion; Good liquidity, low freezing point and safe use; ⑦ EP extreme pressure agent can provide wear protection and other properties under mixed friction conditions.

Gear materials in the reduction gear box are usually metal, powder metallurgy, plastic, MIM, etc., because of the different materials, often output torque, current, temperature, speed, noise requirements are different, at the same time, the structure of the reduction gear box will also have different requirements for the characteristics of the grease, so, different characteristics of the grease came into being.

In general, (1) the more compact the structure of the reduction gear box, the smaller the volume, the smaller the heat dissipation area, the higher the extreme pressure performance of the characteristics of the grease, the better the thermal stability; (2) In the transmission of multiple gear meshing pairs, grease is required to have foam resistance and high adhesion; (3) The working temperature of gear in meshing also changes with the change of working torque, so the grease is required to have good viscose-temperature characteristics and low evaporation at starting and normal operating temperatures; (4) Reduction gear box used such as bearings, oil seals and other materials as well as different gear materials require grease to have good compatibility and oxidation resistance


Choice of grease viscosity:

The output state of the reduction gear box and the gear material used is closely related to the viscosity of grease, usually the output torque of the gear box is relatively large, in order to achieve the life or ensure that the failure form above is extended or not occurred, the gear material is generally selected metal, sticky grease its adhesion is larger, has better protection and anti-psych for metal materials, It can effectively reduce the noise of the gear box, so in general, grease with larger viscosity is selected; And for the output torque is smaller reduction gear box, usually gear material for plastic, if the viscosity of the grease is selected, the gear box in order to overcome the resistance brought by viscosity, the output current or torque will be significantly increased, the operation of the gear box is restricted, therefore, the output torque is smaller or plastic material gear box usually choose viscosity smaller grease.

For high speed gear box, due to the high speed of the gear, its requirements are generally smaller starting current or torque, so the general selection of low viscosity grease.

Generally do not choose different viscous grease in the form of structure, but the planetary gear box as a special form, the following gives the choice of low speed grease

Choice of oil quantity:

The amount of grease in the reduction gear box determines the operating life of gear meshing, noise, etc., too much will cost up. The amount of grease used in the reduction gear box of different structures is different. The choice of the amount of grease in the planetary reduction gear box is usually 50~60% of the blank volume left by the gear meshing is appropriate; The parallel shaft or staggered shaft reduction gear box usually has more white space, and the oil quantity is selected according to the relative low noise of the multi-pair meshing gear; Worm gear, face gear box to gear tooth slot volume 60% is appropriate.


Four. Choice of color:

The color and viscosity of grease itself does not have a certain correlation, but usually the viscosity of the grease its color will be more intense, such as red.

Reduction gear box grease generally includes, ① precision grease; ② food-grade waterproof muffler grease; (3) gear grease; Molybdenum disulfide silencer grease.

The color of molybdenum disulfide silencer grease is black. Other greases are generally white, yellow, red and so on. In general, we can choose these colors of greases at will

Post time: May-18-2023