Abstract: In the dry pipe sprinkler valve arrangement disclosed in the specification, a dry pipe sprinkler line is normally supplied with air at a pressure in a range from about 5 psi to about 20 psi and is connected through a check valve, a dry pipe valve and a manual control valve to a water supply line. The dry pipe valve has a clapper which is normally retained in the closed position by a latch member. An actuating valve having a diaphragm which receives air pressure from the sprinkler line on one side and engages an orifice to which water from the water supply is applied on the other side permits the latch member to release the clapper when the air pressure falls as a result of opening of a sprinkler in the sprinkler line. When the system is being reset after operation the latch is either automatically movable or manually movable by an external handle to restore the clapper to its seated position without requiring opening of the dry pipe valve housing.

Abstract: In the embodiments described in the specification, a deluge and preaction control system supplies water to a sprinkler line through a solenoid control valve which may be actuated by a control panel receiving electrical signals from detectors or from an emergency switch. A preaction riser assembly is arranged to bypass the solenoid control valve to supply water to the sprinkler line through a manual valve and to permit testing of the system. An optional compressor supplying air pressure of at least 2 psi to the sprinkler line and detects damage to the sprinkler line by loss of pressure.

Abstract: A split collar for use with pipe and the like including a pair of discrete semicircular collar halves each having outwardly extending flanges at their terminal ends, and which halves cooperate to define an essentially circular opening. The inner surfaces of adjacent flanges abut along their inboard portions and then generally diverge. Aligned holes of elongated configuration are provided in the flanges to permit securing of the halves together in assembled relation with bolt and nut combinations or the like. The point where the inner surfaces of adjacent flanges commence to diverge is inboard of the inner edges of the bolt head and nut; and, as a result, the halves may be swung to a substantially open position after removal of one of the bolts only and without any loosening of the other bolt.