Quick/emergency/steam/shut-off valve is one of the actuators in the automation system, which is composed of multi-spring pneumatic diaphragm actuator or floating piston actuator and regulating valve. It is widely used for cutting off gas, combustion air, cold air and flue gas. It can be installed on the container joint or riser. When the valve is connected to the riser, the joint size shall be at least 3/4 inch. When the vessel joint is a flanged nozzle and the valve is directly installed on the nozzle, the small size of the joint * is 1 inch. When the vessel joint is a pipe joint and the valve is installed on a short joint, the * small size of the joint is 3/4 inch (except for the exceptions mentioned below). The fittings or pipes between the vessel and the valve shall be reduced to * minimum.

1. Special application

If the nozzle of the vessel is flange type and the connected instrument (such as differential pressure gauge) is a small size threaded joint, then the valve * can be 3/4 inch in diameter and connected to the nozzle of the vessel with a reducing flange and nipple.

2. Double cut-off

Some companies allow the use of double cut-off on parallel instruments, which are connected by a tee directly installed on the nozzle. This method can save space and is more economical in many cases.

3. Flange-mounted membrane level transmitter

This type of instrument installation can be designed to be flush with the vessel wall, and the transmitter can be installed between the vessel nozzle and the transmitter with a valve of the same size as the flange.

It is widely used for cutting off gas, combustion air, cold air and flue gas. The gas cut-off valve is used to cut off the burner and gas pipeline. The combustion air shutoff valve is used to cut off the burner and combustion air pipeline. The hot blast stove is separated from the burner or gas system and combustion air system by the burner shut-off valve during the air supply period. The flue valve isolates the hot blast furnace from the flue. The purpose of the cold air valve is to separate the cold air pipeline from the hot air furnace during the combustion period of the hot air furnace. When the pressure in the cold air pipe drops, the gas in the blast furnace may seep into the cold air pipe through the air mixing pipe to form explosive gas. To avoid this situation, the air mixing shut-off valve is set on the air mixing pipe between the air mixing regulating valve and the hot air pipe.