ENCLOSURE PLACEMENT DEVICE

Abstract

Casing placement device 1, which includes a pneumatic actuator in which a user-operated valve and a self-returning pressure relief valve are incorporated. The actuator may include a piston 12, and the self-returning pressure relief valve may be provided within the piston. The self-returning pressure relief valve may be formed by an orifice 18 through the piston and a valve stem 24 which is urged into contact with the orifice by a resilient member 23. The valve stem and the resilient member may be formed together in a single piece of material. The resilient member may be a resiliently flexible beam and the valve stem a plug.