Abstract: The thermally activated pressure relief valve (10) has a piston (14) normally retained in a closed position and being movable to an open position in case the valve (10) is exposed to an abnormally high temperature. An elastic slotted spring sleeve (20) is disposed within a sleeve (18) of fusible material. In a non-activated state the fusible sleeve (18) maintains the spring sleeve (20) in a radially compressed condition wherein it has a smaller inner diameter effective to retain the piston (14) in the closed position. When the fusible sleeve (18) melts the spring sleeve (20) radially expands to a larger diameter permitting movement of the piston to the open position wherein it is partly received in the spring sleeve (20).

Abstract: A tap for a gas or liquid cylinder is provided that comprises an inverted seat primary valve located in a main portion of a tap body and a secondary check valve spring biased into closed position and located below the lower end of a threaded section of a root end portion of the tap body. Both valves are actuated by an elongated stem extending from the main portion of the tap body into the root end portion. When the tap is fixed to a gas or liquid cylinder, the secondary check valve is located in the cylinder, thereby remaining operative when the tap body is sheared-off at a location where it extends out from a cylinder tap aperture.

Abstract: A tap for a gas cylinder is provided with a position indicator comprising a cylindrical skirt disposed about a cylindrical support member. The skirt is coupled to an actuating wheel of the tap for rotation therewith and for displacement axially with respect to the actuating wheel along the longitudinal axis of the tap. The support member is mounted on the tap body and, in normal operation of the tap, it is retained in fixed position with respect to the tap body. The skirt has an internal screw thread engaging an externally threaded portion of the support member. In closed position of the tap the skirt masks a signaling portion of the support member. When the actuating wheel is rotated to open the tap the skirt is displaced in a direction to uncover the signaling portion to indicate the open position of the tap. The signaling portion may be colored, for example in red.

Abstract: A gas tank valve comprises a wheel handle mounted on a control stem. The wheel handle can be displaced on the control stem in the direction of the longitudinal axis of the stem between a first position, in which the wheel handle is coupled to the stem, with a view to activating it, and a second, uncoupled position, in which the wheel can turn freely on the stem without causing rotational movement of the stem.

Abstract: A tap for a gas or liquid cylinder is provided that comprises an inverted seat primary valve located in a main portion of a tap body and a secondary check valve spring biased into closed position and located below the lower end of a threaded section of a root end portion of the tap body. Both valves are actuated by an elongated stem extending from the main portion of the tap body into the root end portion. When the tap is fixed to a gas or liquid cylinder, the secondary check valve is located in the cylinder, thereby remaining operative when the tap body is sheared-off at a location where it extends out from a cylinder tap aperture.