TACKY LUBRICATING OILS
Lubricating oils with adhesion improvers, tacky viscous, often bituminous, highly viscous lubricants, which are also diluted before use.
Thickening of lubricating oil
Primarily occurs with diesel engines: Combustion residues such as soot, coke, etc. produced by incomplete combustion may be carried with blow-by gases and come in contact with the engine oil as a result of faulty injection pumps, injectors, valves, etc. and cause the oil to thicken.
Thinning of lubricating oil
This occurs in spark-ignition engines if, when the engine is cold, fuel condenses on the cylinder and is then mixed with the lubricating oil through the pumping action at the piston rings. The same phenomenon may occur with fuels with a high final boiling point. When benzin thins lubricating oil in the engine oil, viscosity is reduced and thus jeopardizes lubrication. Testing in accordance with DIN: 51 565.
Non-water-miscible lubricants (metalworking oils) for cutting metal operations. The task of these oils is to lubricate, dissipate heat and remove swarf.
Grease testing machine to determine the high-pressure characteristics of lubricating oils (wear tester). A square test plate is pressed against a moving shaft with the anti-friction bearing ring fitted; to ascertain the loading and appearance of the test specimen.
Tribology covers scientific research and technical applications of friction, wear and lubrication, taking account of design, materials science, regulations imposed by the authorities, etc. Tribo technology also deals with the retention of the value of machines and tools, simplification of lubrication application, minimisation of energy losses plus environmental demands, cost-optimised production and targeted maintenance schedules.
Two-stroke engine oils
When lubricating two-stroke spark-ignition engines, a distinction is made between the following two-stroke engine oils according to the engine type, use, lubrication system, miscibility, mixing ratio, corrosion protection, cleaning effect, biological degradability, etc.:
a) Self-mixing (pre-diluted)
b) Not self-mixing (not pre-diluted) for automatic fresh oil (fresh oil lubrication)
c) Outboard motor oils
The two-stroke oils are classified into three API service categories (American Petroleum Institute): TA, TB, TC for mopeds, scooters, motorcycles and agricultural equipment. There are also the JASO specifications (Japan Automobile Standards Organisation) FA, FB and FC for engine oils with a low sulphate ash content for air-cooled two-stroke engines.
BUCHER AG LANGENTHAL • MOTOREX Lubrication Technology
Bern-Zürich-Strasse 31 • P.O. Box • 4901 Langenthal, Switzerland
Phone +41 (0)62 919 75 75 • Fax +41 (0)62 919 75 95