THERMAL INSULATING TYPE EXHAUST MANIFOLD OF ENGINE

摘要

PROBLEM TO BE SOLVED: To avoid a runout in an outside single pipe and prevent generation of chatter sound due to vibrations and the like while thinning each exhaust single pipe, specifically, an inside single pipe in a thermal insulating type of exhaust manifold which has double-wall exhaust single pipes. SOLUTION: Each of exhaust single pipes 51-54 is composed of an inside single pipe 10 and an outside single pipe 11 which are placed inside and outside so as to be double. The upstream-side ends of the inside and outside single pipes 10, 11 are firmly attached to each other, and firmly attached to an upper flange 7. On the outside peripheral face of the downstream-side end of the inside single pipe 10, a plurality of projections 14 which extend in the axial direction and slidably contact the inside peripheral face of the downstream-side end of the outside single pipe 11 are formed at substantially equal spaces in the peripheral direction.