Leak detection arrangement for valve having sealing means

摘要

A valve includes a plunger which is movable by actuating means such as a solenoid coil, air pressure or other means to move a valve member toward and away from a valve seat. The fluid flow area of the valve is sealed from the actuating means by the diaphragm, O-rings or other forms of sealing structure. In order to insure against leakage past the diaphragm or seal and especially against leakage into the actuating means, the construction includes another diaphragm or seal spaced from the first seal providing a seal space between the first and second diaphragms or seals. In the event of leakage past the first sealing means, flow of the liquid into the space between the first and second sealing means causes an outward flow of the fluid through a detecting passage which thereby provides means which disclose the leakage past the first sealing means so that the first sealing means can be immediately replaced before any damage to the actuating means or to the system itself.