Definition of Steam solenoid valves

Steam solenoid valves are mainly divided into two types based on the steam they handle: saturated steam and superheated steam. The applicable steam sources include boiler steam, steam from thermal power plants, and other related steam types.

Steam solenoid valves are widely used in automatic control systems of various industries and scenarios, such as textile, printing, chemical, plastic, rubber, pharmaceutical, food, building materials, machinery, electrical appliances, surface treatment, scientific research departments, as well as bathrooms, canteens, and air conditioning systems.

For applications with relatively stable temperature and pressure (temperature above 400℃, working pressure below 2.5Mpa), piston-type steam solenoid valves are usually selected.

Structural Features of Steam solenoid valves

Heat Resistance: The electromagnetic and sealing parts adopt special high-temperature-resistant electrical materials and sealing materials, combined with various heat insulation measures.

Wear Resistance: Rational material selection is adopted. The fluid’s lubricating effect is cleverly utilized between the valve cup and guide sleeve, reducing wear and extending service life.

Condensation Resistance: Condensate in steam pipelines is a key factor affecting the operation of steam solenoid valves, but this type of valve is not affected by condensate.

Working Principle of Steam solenoid valves

Steam solenoid valves are categorized into direct-acting type and pilot type. According to their on-off state when de-energized, they can be divided into normally closed (NC) solenoid valves and normally open (NO) solenoid valves.

Normally Closed (NC) Steam Solenoid Valve: When the coil is energized, the armature first lifts the pilot valve plug under electromagnetic force. The fluid on the main valve cup flows out through the pilot valve, reducing the pressure acting on the main valve cup. When the pressure on the main valve cup decreases to a certain value, the armature drives the main valve cup, and the main valve cup opens under pressure difference to allow medium circulation. When the coil is de-energized, the electromagnetic force disappears, and the armature falls and resets due to its own weight. Meanwhile, relying on medium pressure, both the main and pilot valves close tightly.

Normally Open (NO) Steam Solenoid Valve: When the coil is energized, the movable iron core moves downward under suction force, pressing the pilot valve plug down to close the pilot valve. The pressure inside the main valve cup rises; when the pressure reaches a certain value, the pressure difference between the upper and lower parts of the main valve cup is balanced. Under electromagnetic force, the movable iron core presses the main valve cup against the main valve seat, closing the valve. When the coil is de-energized, the electromagnetic suction force is zero. The pilot valve plug and movable iron core are lifted upward by the spring, opening the pilot valve. The main valve cup is pushed up by pressure difference, opening the main valve to allow medium circulation.

Technical Parameters of Steam solenoid valves

Nominal Diameter: DN15～DN600 (G1/8"～24")

Operation Mode: Direct-acting type, pilot type

Operating Environment Temperature: -30—+80℃; -50—+100℃

Coil Operating Temperature: <+50℃, <+85℃

Control Mode: Normally Open (NO), Normally Closed (NC)

International Standard Voltage: AC (380, 220, 110, 24) V; DC (220, 110, 24, 12) V

Circulating Fluid Medium: Steam, saturated steam, and other high-temperature gases

Circulating Fluid Temperature: <+120℃, <+200℃, <+350℃

Circulating Fluid Pressure: -1—64bar

Valve Body Material: Stainless steel (304, 316, 316L), cast steel

Connection Method: Threaded (internal thread, external thread), flanged, welded, clamped, union