Traditionally, the exhaust manifolds on large diesel engines are cast as two parts and connected via sliding joints, which, hitherto, were sealed using machined, cast iron piston rings. These rings worked satisfactorily until new emissions standards were imposed, demanding higher engine operating temperatures. As a consequence, higher exhaust gas temperatures were causing these rings to fail. One leading diesel engine manufacturer is currently using Smalley laminar sealing rings supplied by TFC Europe to overcome the problem.
These are available in a variety of metals, including A286 stainless steel, Inconel x-750, Elgiloy and 17-7 PH/C, among others, and are essentially metallic labyrinth seals comprising multiple rings within a groove.
TFC supplies the Smalley laminar sealing rings in single or double turn form, their arrangement and specific orientation being dependent upon the nature and/or severity of the application environment.