HIGH-TEMPERATURE HIGH-PRESSURE LIQUID FLOW CONTROL VALVE AND METHOD OF PREVENTING FIXING OF ITS STEM

摘要

A cartridge type flow control valve which can be directly installed on a piping without the need of a valve casing and ensure a sufficient sealing property and prevention of stem fixation, comprising a valve disc (1) cantilever-supported and consisting of a valve plate (11) and a stem (12) integrally formed of ceramics, a truncated cone-shaped plug member (2) of a two-layer structure consisting of a high-strength refractory (21) at the axial front and an insulating refractory (22) at the rear and a driving mechanism (3) for the valve disc (1), wherein the valve has a first scaling member (4) consisting of a heat-resisting fiber and wound around the outer periphery of the plug member (2), a mounting member (23) for fixing the plug member (2) and mounted on the mounting seat (103) of an air supply branch pipe (100), a second sealing member (5) consisting of an O-ring to which the mounting member (23) is mounted, and a third sealing member (6) consisting of a gland packing in a bearing member (27) of the stem (12), the plug member (2) being inserted in an opening (102) provided in a flow path wall. A supply of a heated inactive gas or air to a clearance (7) between the stem (12) and an axial hole (24) in the plug member (2) prevents the fixation of the stem.