Engine exhaust gas purifying catalyser - has monolithic elements tightly toleranced to even out stresses

摘要

The catalyser contains monolithic elements with axial passages, held suspended inside a casing. Elements (2) have a protective coating (3) of cement-like material and a flexible wrapping (4) of wire mesh and are held under press by shock absorbing rings (5a, 5b) set in recesses in the ends of the casing. A diametral tolerance of about (+-) 0.4 mm. pref (+-) 0.2 mm is used when applying the protective coating (3) and a coating thickness not exceeding 2 mm. The end faces partic. the edges, should be smooth and flat with a length tolerance of about (+-) 0.2 mm. working, - and shock-load concentrations are thus minimised. The wire mesh wrapping is applied before the coating has set hard.