- 1. INTRODUCTION
There are two main raw materials for the production of lubricants:
• Lube base stock
Lube base stock
One of the products is base stock, which processed further, provides us with base oil. Base oil is the lubricant that is used to lubricate machines.
This base oil needs to have certain chemicals called additives added to it to enhance its performance as a good lubricating agent. These additives together perform diverse functions but each additive has a specific use and together they give the lubricant its character. Depending on the engine the lubricants is to be used; the ratio of base oil to additives varies from 85:15 to 90:10.
Base oils: Base oil is highly refined crude oil or in some cases a synthetic composition and they account for roughly one percent of the total output of petroleum products from crude. It is essentially a by -product obtained during refining of crude and is obtained along with the heavier ends.
Different operating conditions like moisture, dust, exposure to air, high/low temperature, high pressure, corrosion, etc dictate which base oil and which additives should be used.
Most automotive lubes are petroleum based. Synthetic lubes are meant for high performance under extreme conditions of temperature and pressure as in aviation turbines, etc and obviously are very expensive. High performance modern Automobiles like Jaguars. Ferraris, etc also use synthetic oils.
Types of Base oils
Lubricating oil should have the following properties: They should not change their viscosity as operating temperature changes should not easily oxidize and produce sludge’s and gums, should protect engine parts from corrosion, should also act as coolants that take away frictional heat, should have detergent properties that keep the machine surfaces clean by constantly removing and dispersing foreign matter etc.
The most important physical characteristics of lube oil are viscosity and flash point. The oil should be viscous enough to prevent metal contact besides reducing viscous drag. Flash point is the temperature at which oil forms an ignitable mixture with air when it is heated under specified conditions. It denotes the presence of volatile constituents in oil and is indicative of the temperature up to which it can safely be used.
CLASSIFICATION AND SPECIFICATION OF LUBRICANTS
Lubricants for their applications can be broadly classified into:
- Industrial lubricants
- Automotive lubricants
- Aviation & Marine grade lubricants
A label may, at best, be considered as the symbol of a manufacturer’s authentication of oil’s performance claim. A label generally tends to describe the basic performance level of motor oil consistent with its use in an engine application and its viscosity characteristics. Sometimes special features such as energy conserving ability, smokeless ness, chemical and theological design are also either described or implied by the use of certain labels, special labels like "All Synthetic" signify the use of exotic base fluids. While the Society of Automotive Engineers (SAE) grades are used universally to specify viscosity characteristics and low temperature rheology of motor oils, several systems of rating the performance level coexist in the global marketplace.
Probably, the most popular motor oil performance categories are those that have been instituted by the American Petroleum Institute (API).
Apart from the API, there exists several independent motor oil certification and labeling systems including the US military, Committee of Common Market engine Constructors (CCMC) in Europe and JASO (Japanese Automotive Standards Organization). The Bureau of Indian Standards (BIS) performance categories of Engine crankcase oils are generally drawn from the various API categories, US military specs and CCMC categories.
In additional to the performance categories and labels of the above mentioned Technical Societies and Institutions, several labels of approvals by European, Japanese and U.S. OEMs (Original equipment Manufacturers) arc also abundantly found on motor oil cans. Such labels are very often used by oil marketers to achieve market/product segmentation and to embellish the performance superiority claim over specification products.