Steam Solenoid Valves

Steam Solenoid Valves

Solenoid valves for saturated steam and hot water are specifically designed to cope with the aggressive nature and temperature of hot steam. There are two common types of steam solenoid valve either direct acting as found in a most miniature solenoid valves with small 1/8", 1/4", 3/8" or 1/2" threaded port or pressure assisted (also known as servo or floating piston) solenoid valve as typically found from sizes 1/2", 3/4", 1", 11/4", 11/2" and 2" BSP or NPT Thread or even flanged PN16, ANSI150Lb or JIS10K port sizes DN25, DN32, DN40, DN50, DN65, DN80, DN100, DN125, DN150, DN200, DN250 and DN300.

	Steam solenoid valve miniature SA series. Function: 2/2 way Normally Closed Operation: Direct Acting Pressure: 0 to 10 Bar Port: 1/8", 1/4" or 3/8" BSP or NPT Thread. Orifice: 3mm, 3mm and  4mm Body: Brass Seals: PTFE Coil: Class H 180C DIN43650A IP65, option Class N 200C Rated Voltage: 12vDC, 24vDC, 48vDC or 12vAC, 24vAC, 48vAC, 110vAC, 230vAC Good points: Compact, low cost, reduced power consumption, works regardless of pressure, available normally open. Bad points: Low flow small orifice, only available in small port sizes
	Steam solenoid valve PU225S series Function: 2/2 way Normally Closed Operation: Pressure Assisted Pressure: 0.5 to 10 Bar Port: 3/8", 1/2", 3/4", 1", 11/4", 11/2" or 2" BSP or NPT thread or flange Orifice: 15mm, 15mm, 20mm, 25mm, 38mm,38mm, 50mm Body: Brass Seals: PTFE Coil: Class H 185ºC  Voltage: 12vDC, 24vDC, 48vDC or 12vAC, 24vAC, 48vAC, 110vAC, 230vAC, 380vAC Good points: High flow, good range of threaded and flanged sizes Bad points: Relies on a minimum 0.5 bar pressure difference to operate.
	Steam solenoid valve SA series Function: 2/2 way Normally Closed Operation: Pressure Assisted Pressure: 0.5 to 10 or 12 Bar Port: 3/8", 1/2", 3/4", 1", 11/4", 11/2" or 2" BSP or NPT thread or flange Orifice: 15mm, 15mm, 20mm, 25mm, 35mm,35mm, 50mm Body: Brass Seals: PTFE Coil: Class H 185ºC or Class N 200ºC 100% Duty Rated Voltage: 12vDC, 24vDC, 48vDC or 12vAC, 24vAC, 48vAC, 110vAC, 230vAC, 380vAC Good points: High flow, good range of threaded and flanged sizes, available normally open Bad points: Relies on a minimum 0.5 bar pressure difference to operate.
	Steam solenoid valve USLF series Function: 2/2 way Normally Closed Operation: Pressure Assisted Pressure: 0.5 to 10 Bar Port: Flanged DN65, DN80 and DN100 PN16, ANSI150Lb or JIS10K Orifice: 65mm, 80mm, 100mm Body: Cast Iron FC20 Seals: PTFE Coil: Class H 185ºC, option Class N 200ºC Voltage: 12vDC, 24vDC or 24vAC, 110vAC or 230vAC Good points: High flow, 1 piece flange casting, available normally open Bad points: Relies on a minimum 0.5 bar pressure difference to operate.

Steam solenoid valves are typically normally closed (power to open) so the fail-safe position is closed, there are options for normally open (power to close) fail-safe open but really it is wise to avoid these for health and safety reasons as without power supply the valve will stay open.

Steam Solenoid Valve Materials of Construction and Industries.

Steam solenoid valves are available in a range of materials including Brass, Bronze, Stainless Steel and Cast Iron which can be used depending on the application and environment. Stainless steel solenoid valve are typically used for food industry applications where as Brass or Bronze are generally used for industrial systems such as steam boiler outlets, commercial steam washing machines or steam presses in laundries, vending coffee machines, sterilising systems, moulding and autoclave systems.

The internal seals of steam solenoid valves should generally PTFE, which can withstand steam temperatures up to 200 centigrade however a cheaper elastomer seal such as EPDM has been used in some instances but this has temperature limitations of under 150 degrees centigrade.

The solenoid coils will also be rated for high temperature applications, typically H (180 C) or N (200C) Rated

Helpful Hint: It is best practise to use a solenoid valve with PTFE seals which are rated up to 200C for steam, however for hot water EPDM can be OK up to about 150C maximum.

There is a helpful chart showing steam temperatures related to pressure, as these are directly related.