A car includes dozens of nodes in which moving parts made of metals or their alloys interact. And in each such unit, large frictional forces arise due to considerable rotational speeds and high mechanical loads.
Effective lubricants must be used to counteract the negative effects of friction. Among all types of lubricants in a car, lithium greases are most often used. We will talk about them in this material.
Lithium grease: what is it?
Lithium greases are viscous gel-like substances containing lithium. Such lubricants appeared in the forties of the last century and now represent multipurpose antifriction lubricants modified almost to the ideal, produced both in Russia and abroad, by enriching simple petroleum oils with lithium soap.
In appearance, different types of lithium greases can differ both in color (from pale yellow to dark brown) and in the degree of viscosity, which determines the specifics of each particular grease.
Lithium greases popular among modern motorists are widely used in other areas:
- radio-technical devices;
- aircraft equipment;
- high precision measuring mechanisms;
- machines and mechanisms subject to conservation, including heavy industrial and military equipment;
- all kinds of nodes in which the processes of friction, rolling, sliding take place;
See also : Application of graphite grease in a car.
Characteristics of lithium greases
Lithium greases are characterized by the following performance properties:
- Heat resistance. Lithium greases can be successfully used in the most severe climatic conditions, ranging from frosty northern latitudes, in which the air temperature drops to minus 60 ° C, to hot workshops, in which mechanisms must withstand temperatures above 100 ° C.
- Viscosity. Litols envelop the surfaces of metal parts in an optimal way, protecting them from the effects of adverse factors in an aggressive environment. Lithium-containing emulsions retain this property both at low and high temperatures.
- Chemical resistance. Special additives protect metal parts from oxidation by air and water. At the same time, certain types of lithols can adversely affect plastic or aluminum elements, which can limit the scope of their application only to metal (non-aluminum) assemblies.
- Easy to clean parts. Most lithium greases are easily washed off with plain water, which makes cleaning parts easier and cheaper.
- Ability to recover. Lithium grease can restore molecular bonds on the surface of rubbing parts, which is the main condition for restoring their performance, preventing destruction and extending their service life.
See also :The engine eats oil : why and what to do?
The use of lithium greases in a car
The main purpose of automobile anti-friction lubricants is not just to reduce friction, but to increase the performance of a car, extend its life cycle. The service life of moving metal parts is easily achieved through timely maintenance, which consists of cleaning and lubricating. For normal operation of the car (especially in the post-warranty period), it is necessary to regularly check the lubricant level in all units and replace it in a timely manner if a shortage or thickening is detected.
Alarms about the need to apply lubricant are extraneous sounds uncharacteristic for normally operating mechanisms: squeaks, knocks, buzzing, etc. long-term storage without operation (for example, for vacation, business trip, watch, etc.).
In this case, lithium greases must be used strictly for their intended purpose, since different car components require different compositions:
- For CV joints, lithium greases are used with the addition of molybdenum disulfide. Such lubricants well protect mechanisms in which high rotational speeds take place, both from mechanical influences and from short-term heating up to 130 - 150 ° C.
- Lithium grease with the addition of Teflon has been successfully used to lubricate cables, threaded joints, chains and other rubbing parts. This type of lubricant has a particularly high resistance to external aggressive factors (temperature extremes, humidity, pollution and dust), which contributes to reliable protection of exposed parts from corrosion and oxidation.
- Complex lubricants containing a metal conditioner are used to protect hard-to-reach vehicle parts operating under high mechanical pressure. Such lubricants can perform their functions for a long time, without the need for periodic replacement.
- For all other units and parts of machines, universal lithium greases with balanced universal qualities (water repelling effect, good stickiness, wide temperature range, resistance to external adverse influences) can be used.