The common utilized valves in heating system include globe valve, gate valve, butterfly valve, ball valve, check valve, safety valve, pressure reduction valve, pressure maintaining valve, balanced valve, regulating valve and other self-operating or electric regulating valve.
Globe valve: Globe valve is used to cut off medium flowing. It has function of regulating and large pressure losses. Globe valve is commonly utilized for heating system to cut off steam in pipe. "J" represents globe valve.
Gate valve: Gate valve is used to cut off medium. When the valve opened completely, medium can flow through gate valve like pipeline. It does not need to change direction and has low pressure losses. Gate valve has bad regulating function. "Z" represents gate valve.
Check valve: Check valve is also called as cut-off valve or one-way valve. Check valve allows medium to flow in one direction. When pressure behind valve is higher than the pressure before valve, check valve closes automatically. Check valve has a lot of types including lift check valve and swing check valve. The shape of life check valve is similar to globe valve, having large pressure losses. For that, life check valve is less used in heat exchange station. "H" represents check valve.
Butterfly valve: Regulating the angle of disc can open or close the valve. Resistance caused by medium flow is large. For that, butterfly valve is less utilized. "D" is used to represent butterfly valve.
Safety valve: Safety is used to decompress to protect equipments and system when medium excess pressure. In some situations, parted hydraulic safety valve can be used as system constant pressure valve after being improved. Safety valve has various types. "Y" is used to represent safety valve.