Pump plunger for fuel injection pump of IC engine - comprises coating head and/or shaft with chromium and/or tungsten carbide(s) or oxide(s) ceramics

摘要

Pump plunger has a hard material coating (9, 14) on the head (1) and/or shaft (6), deposited in recesses, pref. 0.05-0.2 mm deep, in the material. Pref. hard materials are Cr and/or W carbides or oxide ceramics. The coating is protected mechanically and from fuel injection pressure by retention of the limiting edges (10a, 10b, 10c) of the plunger. ADVANTAGE - Long operating life with low risk of damage.