Principles of lubricant selection according to the working conditions of machinery
author: Ann
2024-10-22
Burden
For large loads, lubricants with high viscosity or good oleophobic and extreme pressure properties should be used. On the contrary, the load is small, should choose the lubricant with small viscosity. Intermittent or impact mechanical movement, easy to destroy the oil film, should be used with a larger viscosity or good extreme pressure lubricant, or with this lubricant made of taper into the smaller (harder) grease.
For large loads, lubricants with high viscosity or good oleophobic and extreme pressure properties should be used. On the contrary, the load is small, should choose the lubricant with small viscosity. Intermittent or impact mechanical movement, easy to destroy the oil film, should be used with a larger viscosity or good extreme pressure lubricant, or with this lubricant made of taper into the smaller (harder) grease.
Speed
High speed, need to choose the viscosity of the smaller lubricant or with the viscosity of the smaller lubricant made of grease; on the contrary, with the viscosity of the larger lubricant or with the viscosity of the larger lubricant made of grease. For high-speed rolling bearings, in order to supplement the mechanical stability of all grease and into the drain, as well as to overcome the role of centrifugal force, it is best to choose a thicker No. 3 grease; for general speed is not too high for bearings, in order to reduce the torque of the bearings, especially the starting torque, it is possible to choose a low consistency of the grease.
High speed, need to choose the viscosity of the smaller lubricant or with the viscosity of the smaller lubricant made of grease; on the contrary, with the viscosity of the larger lubricant or with the viscosity of the larger lubricant made of grease. For high-speed rolling bearings, in order to supplement the mechanical stability of all grease and into the drain, as well as to overcome the role of centrifugal force, it is best to choose a thicker No. 3 grease; for general speed is not too high for bearings, in order to reduce the torque of the bearings, especially the starting torque, it is possible to choose a low consistency of the grease.
Temperature
In high temperature conditions, should be used viscosity, high flash point, good oil and oxidation stability of the lubricating oil or with good thermal stability of the base oil and thickener (lithium soap, load calcium soap, load aluminum soap, etc.) made of higher dropping point of the grease. In low-temperature conditions, should be used with less viscosity, low freezing point of the lubricating oil or made of this oil with better low-temperature performance of the grease. The friction parts with big temperature change should use lubricating oil with better viscosity and temperature performance or grease with wider temperature range (such as general-purpose lithium grease).
In high temperature conditions, should be used viscosity, high flash point, good oil and oxidation stability of the lubricating oil or with good thermal stability of the base oil and thickener (lithium soap, load calcium soap, load aluminum soap, etc.) made of higher dropping point of the grease. In low-temperature conditions, should be used with less viscosity, low freezing point of the lubricating oil or made of this oil with better low-temperature performance of the grease. The friction parts with big temperature change should use lubricating oil with better viscosity and temperature performance or grease with wider temperature range (such as general-purpose lithium grease).
Moisture
In a humid working environment, or working conditions with more contact with water, should be used to resist emulsification ability of oil, rust-proof performance of better lubricants, grease, can not choose sodium-based grease.
In a humid working environment, or working conditions with more contact with water, should be used to resist emulsification ability of oil, rust-proof performance of better lubricants, grease, can not choose sodium-based grease.
Friction surface precision
Rough surfaces require the use of lubricants and greases with higher viscosity or lower taper. Conversely, lubricants and greases with smaller viscosity or larger taper in should be used.
Rough surfaces require the use of lubricants and greases with higher viscosity or lower taper. Conversely, lubricants and greases with smaller viscosity or larger taper in should be used.
Friction surface position
On vertical guide rail and screw, the lubricant is easy to lose, and a lubricant with higher viscosity should be used. Vertical bearings are suitable to use grease, which can reduce the loss and keep lubrication.
On vertical guide rail and screw, the lubricant is easy to lose, and a lubricant with higher viscosity should be used. Vertical bearings are suitable to use grease, which can reduce the loss and keep lubrication.
Lubrication method
In the circulating lubrication system, it is required that the oil change cycle is long and the heat dissipation is fast, so the lubricant with smaller viscosity, better anti-foaming and anti-oxidation stability should be used. In the splash and oil mist lubrication system, in order to reduce the oxidation of lubricant, should be used with anti-oxidation, anti-foam additives lubricant. In the centralized lubrication system, in order to facilitate the delivery, should be used for low consistency of the No. 1 or No. 1 grease.
In the circulating lubrication system, it is required that the oil change cycle is long and the heat dissipation is fast, so the lubricant with smaller viscosity, better anti-foaming and anti-oxidation stability should be used. In the splash and oil mist lubrication system, in order to reduce the oxidation of lubricant, should be used with anti-oxidation, anti-foam additives lubricant. In the centralized lubrication system, in order to facilitate the delivery, should be used for low consistency of the No. 1 or No. 1 grease.
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