The Influence of the Combustion Products on the Piston-Ring Wear of a Diesel Engine : 2nd Report, Firing

Abstract

A small type Diesel engine is operated with the fuel containing various sulphur compounds and under various engine conditions. These tests show that (1) the top-ring wear is large owing to the fact that it is surrounded with the combustion products, so when the gas-tightness of the top-ring is inadequate, the 2nd-ring wears in the same order ; (2) the more sulphur is contained in the fuel and the lower the temperature of cooling water goes down, the more the corrosive wear increases. The cylinder surface is corroded by the condensed liquids of the engine exhaust gas ; containing much SO₃, the liquid easily penetrates into the lubricating oil, and attacks the metal surface. Chemical analysis shows that SO₃ presents itself so much in the exhaust gas, that the ratio SO₃/SO₂ is about 10%.