The flow cross-section between the clear valve housing and valve cone is larger than the flow cross-section of the valve seat. The force of the compression spring is only slightly greater than the pressure differential corresponding to overcoming the flow resistance of the flowing medium through the free cross-section between the clear valve housing and valve cone. As a result, the valve is kept open at this pressure differential. If a sharp pressure drop occurs between the valve and consumer due to bursting or tearing of the compressed air lines, the valve cone is pressed against the valve seat and the flow is interrupted. A small amount of compressed air can flow through the small bore in the valve cone, which on the one hand can no longer cause the hose to whip, and on the other hand, after repair of the line, refills the space between the valve and consumer until pressure equalization is achieved, so that the valve cone is lifted from the valve seat by the compression spring and releases the full flow again.
These valves have been tested by the DMT Institute for operational use.