What Is the Difference Between Lubricants and Lubricants?

First understand the composition of some lubricants and lubricants.

Lubricating oil generally consists of two parts: base oil and additives. Base oil is the main component of lubricating oil and determines the basic properties of lubricating oil. Additives can make up for and improve the deficiencies in the performance of the base oil and give some new properties and are an important part of lubricating oil.

Grease is mainly composed of three parts: thickener, base oil, and additives. Generally, the thickener content in grease is about 10%-20%, the base oil content is about 75%-90%, and the content of additives and fillers is less than 5%.

1. Base oil

Base oil is the dispersion medium in the grease dispersion system, which has a great influence on the performance of the grease. Generally, greases mostly use petroleum lubricants of medium viscosity and high viscosity as the base oil. In order to meet the needs of mechanical lubrication and sealing working under harsh conditions, some use synthetic lubricants as the base oil, such as ester oil, silicone oil, Poly-alpha-olefin oil, etc.

2.Thickener

Thickener is an important component of grease. The thickener is dispersed in the base oil and forms the structural skeleton of the grease, allowing the base oil to be adsorbed and fixed in the structural skeleton. The water resistance and heat resistance of grease are mainly determined by the thickener. There are two main categories of thickeners used in preparing greases. Soap thickeners (i.e. fatty acid metal salts) and non-soap thickeners (hydrocarbons, inorganic and organic types).

Soap-based thickeners are divided into three types: single soap base (such as calcium-based grease), mixed soap base (such as calcium-sodium base grease), and composite soap base (such as complex calcium-based grease). 90% of greases are made with soap-based thickeners.

3. Additives and fillers

One type of additive is needed for grease, called peptizer, which makes the combination of oil and soap more stable, such as glycerin and water. Once water is lost in calcium-based grease, its structure is completely destroyed and cannot form grease. For example, glycerol in sodium-based grease can adjust the consistency of the grease. The other type of additives is the same as in lubricants, such as antioxidants, anti-wear and rust inhibitors, but the dosage is generally higher than that in lubricants. Such as phosphate ester, ZDDP, Elco extreme pressure anti-wear agent, compound agent, dropping point increasing agent, etc. Sometimes, in order to improve the grease's ability to resist loss and enhance lubrication, some graphite, molybdenum disulfide and carbon black are often added as fillers.

You will find that lubrication is basically similar to grease. Grease has an additional thickener.

So what are the differences between grease and lubricant applications and how should you choose them?

The main reasons for choosing grease are:

Cost-effectiveness

Simple - Grease is easily retained on gear surfaces or within the gearbox, so no complex sealing arrangements are required compared to oil lubrication

Main applications for selecting grease exceptions:

Operating conditions require unacceptably short grease relubrication intervals

Lubricating oil must be used for other reasons (e.g. in gearboxes)

Oil lubrication needs to be considered when heat dissipation through circulating oil is required

When cleaning or removing used grease becomes tedious or expensive.