Control valves

摘要

A control valve has a gland seal comprising a sealing member formed of a flexible polymeric material, preferably PTFE. The sealing member comprises a tubular portion located around the valve spindle and a radially extending flange encircling the tubular portion, the sealing member being supported within the hollow body by its radially extending flange. The spindle and surrounding tubular portion have adjacent surfaces, at least one of which has an annular ridge biased into sealing contact with the other surface.