METHOD FOR PROCESSING VALVE MECHANISM CONSTITUTING MEMBER

摘要

A surface treatment method for a valve mechanism constituting member, by which the product stably providing a predetermined pulsation reduction effect can be supplied and with which the pulsation reduction effect can be maintained over a long period. Recesses (60) are formed by laser processing either in the periphery (seat surface (51)) of a suction hole (24) with which the suction valve (30) of a valve plate (2) is in contact, or in a part of the suction hole (24) coming into contact with the valve plate (2). Alternatively, a ridge (61) may be formed around each recess (60) by laser processing. To form the ridge (61), hardness of the ridge (61) is adjusted to a level relatively higher than that of other portions by application of laser light.