The Effect of Grease Consistency on its Performance

The consistency of grease has the following effects on its performance:

Shear resistance

The higher the consistency grade, the greater the viscosity of the grease is usually, and the better the shear resistance is, which is suitable for use in high load and high temperature environments. It can form a thicker oil film on the surface of mechanical parts to reduce friction and wear.

Sealing

Thicker grease can better fill the gap and play a certain sealing role to prevent dust, impurities, etc. from entering the friction parts.

Applicable temperature range

Generally speaking, high-viscosity grease is less likely to flow at high temperatures and has better heat resistance; while low-viscosity grease has relatively good fluidity at low temperatures and is more suitable for low-temperature environments.

Starting resistance

When the shear rate is very low (such as the equipment startup stage), the viscosity of the grease has a great relationship with the starting of the lubricated friction parts. Since the grease has a high viscosity when the shear rate is low, the grease with too high a viscosity will increase the starting resistance, especially at low temperatures, which may affect the low-temperature starting and even cause difficulties.

High-speed adaptability

When the machine speed is high, the lubricant viscosity is required to be low. At this time, the grease structure is damaged more severely, and the viscosity becomes low, which can adapt to the requirements of high-speed operation. When the speed is slow, the grease viscosity is required to be larger, and the viscosity of the grease is usually larger at low shear speeds.

Filling and maintaining

Grease with appropriate consistency can make it easy to fill and maintain the grease on the friction surface to maintain a long-lasting lubrication effect. If the consistency is too thin, the grease may be lost on the friction surface due to insufficient adhesion; if it is too thick, it is not easy to enter and fill the friction surface, and the internal friction resistance of the grease is large, so it cannot be applied to the lubrication requirements of high-speed running parts.