Method of making an electrically-operated fluid valve having improved sealing of the valve needle to the valve seat when the valve is closed

摘要

A method of making an electrically-operated fluid valve for improving the metal-to-metal sealing of the valve needle to the valve seat, particularly of the rounded tip end of the needle to a frusto-conical depression in the seat. The method comprises applying a controlled axial compressive load to the seated needle to cause the annular zone of sealing contact between the needle and the seat to be coined.