What the meanig of «SAPS»?
SAPS is an abbreviation for the names of components, namely sulphated ash (SA), sulphur (S) and phosphorus (P) in engine oils. The term was introduced by the Association of European Automobile Manufacturers (ACEA). ACEA divides engine oils into the following categories according to their SAPS content:
• high SAPS are oils that have high levels of sulfated ash, phosphorus and sulfur.
• mid SAPS are oils which have medium levels of sulfated ash, phosphorus, sulfur
• low SAPS are oils that have low levels of sulfated ash, phosphorus and sulfur.
Historically, high SAPS engine oils were the first to appear. However, with the growth of environmental requirements and the emergence of additional exhaust treatment devices – catalytic converters, diesel and gasoline particulate filters, etc., oils with low SAPS content have gained relevance. It turned out that high SAPS oils with high levels of sulfated ash, sulfur and phosphorus reduce the efficiency and service life of particulate filters and catalytic converters.
Sulfated ash is an insoluble sludge that forms when engine oil burns. During normal engine operation, a small portion of the engine oil always enters the combustion chamber. Oil with high metal-containing additives (high SAPS) burns and forms additional ash particles that accumulate in the pores of the particle filter, dramatically reducing its service life. These particles can also damage the catalytic converters by preventing the catalyst from removing toxic substances from the exhaust gases.
Sulfur and phosphorus are also commonly found in engine oil additives. Their combustion produces sulfur and phosphorus oxide compounds that block the particulate filter and can contribute to the irreversible deactivation of catalytic converters.
Modern mid and low SAPS engine oils have reduced levels of sulfated ash, sulfur and phosphorus, which contributes to the normal and long-term operation of particulate filters and catalytic converters.
Engine oils for passenger cars and small trucks in relation to the level of SAPS according to the ACEA classification are designated as:
• high SAPS oils – ACEA A3/B3, A3/B4, A5/B5, A7/B7;
• mid SAPS oils – ACEA C2/C3/C5/C6;
• low SAPS oils – ACEA C1/C4.
Truck engine oils in relation to SAPS level according to ACEA classification are designated as:
• high SAPS oils – ACEA E4/E7;
• mid and low SAPS oils – ACEA E6/E8/E9/E11.
Truck engine oils in relation to the level of SAPS according to the API classification are designated as:
• mid and low SAPS oils – API CJ-4/CK-4/FA-4.