Head gasket with pre-embedded metal shim and method of using same

摘要

A head gasket comprising a laminate, metallic core and fiber- elastomer facing layers on each major surface of the core and defining a plurality of combustion openings, oil and water holes and bolt holes. A thin shim is disposed on one of the facing layers. The shim has arcuate elements lying adjacent to each of a pair of adjacent combustion openings. U- shaped armors at each combustion opening have legs overlapping the edges of the facing layers and portions of the shim elements adjacent to the edges of the combustion openings, with the shim elements extending radially outwardly beyond the armor legs. When the armors, shim and facing layer are precompressed after assembly and during the manufacturing process, the facing layer is densified through a reduction in thickness under the armor, is greatly densified under the armor and shim through a reduction in thickness by approximately the thickness of the shim, and densified in proportion to the shim thickness where the shim elements extend radially outwardly beyond the legs. The gasket is substantially unreduced in thickness radially beyond the shim and armor.