Solenoid Valves

Brass Solenoid Valve sizes M5 through to 3" BSP, NPT or DN10 to DN150 flange ports available in both 2/2 way normally open (fail safe open) or 2/2 way normally closed (fail safe Closed) function, either direct acting or pilot operation. Typically a brass solenoid valve is  constructed with a Brass Body and a mixture of Brass and various grades of internal stainless steel parts such as AISI304 core tube, AISI430F armature and AISI302 springs and typically a choice of elastomer sealing materials. Brass is generally a good all round robust general purpose material making a brass solenoid valve a well suited general purpose solenoid valve for the control of Air, Water, Vacuum, Oil, Atmospheric gases and most non aggressive and non corrosive applications.

However the sealing parts of a Brass solenoid valves will typically be either NBR (Nitrile Buna Rubber) which is good for air, water, mineral oils, vacuum, vegetable and hydraulic oil.

EPDM (Ethylene Propylene Diene Monomer) which is good for ozone, fire proof hydraulic oils and alcohols.

FKM Fluoro elastomer (Fluorocarbon) has excellent heat resistance and are suitable for mineral oils and ozone. FKM has good resistance to most acids but brass solenoid valves are not suitable for corrosive media such as acids and alkali's so we have to rule this option out. If aggressive or corrosive chemicals are present we strongly suggest using either a stainless steel solenoid valve or a plastic solenoid valve depending on the media to be controlled.

Typically a general purpose brass solenoid valve will have NBR seals however please read the materials of construction in the technical articles section if you would like more information.

Brass solenoid valves operation and function.

brass solenoid valve miniature series

2/2 Way Normally Closed Miniature Brass Solenoid Valve.

Function: 2/2 way normally closed brass miniature solenoid valve has 2 ports (inlet and outlet) with 2 positions (open or closed), being normally closed means this miniature solenoid valve fail-safe position is closed thus requiring electrical power to open the solenoid valve and allow media flow. These are the most commonly used type of small compact 2 way solenoid valves found in small water, air, oil and gas systems requiring low flow, compact, typically low power (4 to 20 watts), reduced cost and suitable for most low, medium and high pressure applications depending on specification. This small or miniature solenoid valve typical operation is direct acting and hence do not rely on a guaranteed pressure difference between inlet and outlet ports to operate. Typically fitted with low to medium power coils (the electro magnet). Pressure ranges can vary according to specification (orifice and coil power) from 0 or vacuum to 10, 20, 100 or even 200 bar pressure or more. Sizes typically 1/8 Thread through to 1/2 thread.

 miniature brass solenoid valve

2/2 Way Normally Open Miniature Brass Solenoid Valve.

Function: 2/2 way normally open miniature solenoid valve has 2 ports (inlet and outlet) with 2 positions (open or closed), being normally open means miniature solenoid valve fail-safe position is open thus requiring electrical power to close the solenoid valve and stop the flow of media. These are not such a popular solenoid valve series but they do offer small compact 2 way flow control for small water, oil, gas and vacuum systems requiring low or reduced flow, low cost, compact ON/OFF control for most low, medium and relatively high pressure applications. These small or miniature solenoid valve typical operation is direct acting and thus do not rely on a guaranteed pressure differential i.e. higher inlet pressure to outlet pressure difference to operate. Typically fitted with medium power coils (the electro magnet). Typical pressure ranges from 0 to 25 bar. Sizes typically 1/8 Thread through to 1/2 thread. Helpful hint: if you shake the solenoid valve the armature will typically rattle unlike a normally closed version.

brass solenoid valve 2/2 normally closed direct

2/2 Way Normally Closed Zero Rated Brass Solenoid Valve.

Function: 2/2 way zero rated normally closed solenoid valve has 2 ports (inlet and outlet) with 2 positions (Open or closed), being normally closed or fail-safe closed with electrical power required to open the valve and allow media flow. These are by far the most common type of brass general purpose solenoid valve as with power removed or in an emergency shut down situation this solenoid valve will fail-safe into the valve closed position stopping the flow of media. The operation of the model shown here is hung diaphragm, also known as the assisted lift, direct acting and kick pilot. Here we have advantages of a diaphragm or piston attached directly or hung from the armature situated  within core tube which directly controls the flow of media through the solenoid valve. In this way no pressure differential is required for the valve to operate (i.e. guaranteed higher inlet pressure than outlet pressure) thus offering almost guaranteed valve operation and with this diaphragm or piston design offering excellent flow characteristics and is suitable for most vacuum, low pressure, closed loop, gravity fed and medium pressure systems. Typical pressure ranges are 0 / Vacuum to pressures up to or exceeding 10 Bar. Typical sizes ranging from 3/8 thread to 2 " thread and also flange options to DN300. Helpful hint: this design of solenoid valve will typically have coil mounted centrally with no visible adaptor between core tube and solenoid valve body.

 

brass solenoid valve 2/2 normally closed pilot

2/2 Way Normally Closed Servo Assisted Brass Solenoid Valve.

Function: 2/2 way normally closed solenoid valve has 2 ports (inlet and outlet) with 2 positions (Open or closed), being normally closed or fail-safe closed with electrical power required to open the valve and allow media flow. These are a common type of brass general purpose solenoid valve as with power removed this solenoid valve will fail-safe into the valve closed position stopping the flow of media. The operation of the model shown here is known as pressure assisted also known as servo assisted or floating diaphragm or floating piston. Here we have advantages of the media pressure being utilised to open or close the solenoid valve, thus reducing cost and power consumption. When de energised the media pushes the diaphragm or piston firmly into the closed position preventing flow through the valve. When electrical power is applied to the coil (electro magnet) this in turn lifts the armature revealing a pilot hole where the media above the piston or diaphragm is released downstream via this pilot control circuit. The media inlet pressure then over comes the pressure above the sealing diaphragm / piston lifting it into the open position allowing flow though the solenoid valve. When power is removed the control circuit is again closed stopping the media pressure above the seal escaping downstream, the pressure above the sealing diaphragm again accumulates forcing the solenoid valve seal back into the closed position. This diaphragm or piston design offers excellent flow characteristics and are typically less expensive than assisted lift solenoid valves, in fact there is typically an exponential cost saving from sizes above 1" thread. These solenoid valves are suitable for most medium to high pressure and open to atmosphere systems. Typical pressure ranges are 0.5 to pressures exceeding 100 Bar. Typical sizes ranging from 3/8 thread to 3 " thread and also flange options to DN500.

Helpful hint: This solenoid valves totally relies on the pressure differential between inlet and outlet ports to operate. Also the solenoid coil is typically mounted over the outlet port. 

brass solenoid valve 2/2 normally open direct
 

2/2 Way Normally Open Direct Acting Brass Solenoid Valve.

Function: 2/2 way normally open solenoid valve has 2 ports (inlet and outlet) with 2 positions (Open or closed), being normally open or fail-safe open with electrical power required to close the solenoid valve and stop the flow of media. These are not as common as normally closed solenoid valves however they do have the advantage of being fail-safe open and are ideal for systems that require a solenoid control valve to remain open for very long periods of time to allow flow within process systems where their are other emergency fail-safe valves elsewhere in the system. In this way power consumption and heat build up from the solenoid coil is greatly reduced. The operation of the model shown here is hung diaphragm, also know as assisted lift, direct acting and kick pilot. here we have the advantages of a diaphragm or piston attached directly or hung from the armature situated within the core tube which directly controls the flow of media through the solenoid valve. In this way no pressure differential is required for the solenoid valve to operate (i.e. guaranteed higher inlet pressure than outlet pressure) thus offering almost guaranteed valve operation and with this diaphragm or piston design offering excellent flow characteristics and is suitable for most vacuum, low pressure, closed loop, gravity fed and medium pressure systems. Typical pressure ranges are from 0 / vacuum to 10 bar.

Helpful hint: however keep in mind the valve fail-safe position is open and it is advised that a fail-safe close valve is installed elsewhere in the system.

brass solenoid valve 2/2 normally open pilot 

2/2 Way Normally Open Servo Assisted Brass Solenoid Valve.

Function: 2/2 way normally open solenoid valve has 2 ports (inlet and outlet) with 2 positions (Open or closed), being normally open or fail-safe open with electrical power required to close the solenoid valve and prevent flow of media. The operation of the model shown here is known as pressure assisted also known as servo assisted or floating diaphragm or floating piston type. Here we have advantages of the media pressure being utilised to open or close the solenoid valve, thus reducing cost and power consumption. When de energised the media is allowed to lift the diaphragm or piston up into the open position allowing flow of media through the solenoid valve. When electrical power is applied to the coil (electro magnet) pushes the armature inside the core tube down blocking a pilot hole where the media above the piston or diaphragm was being released downstream via the outlet port. The media pressure then builds above the diaphragm or piston pushing it down into the closed position preventing flow though the solenoid valve. When power is removed the control circuit is again open allowing the media pressure above the seal to escape downstream allowing the inlet media pressure to force the solenoid valve (piston or diaphragm) back up into the open position. This diaphragm or piston design offers excellent flow characteristics and are typically less expensive than assisted lift solenoid valves, in fact there is typically an exponential cost saving from sizes above 1" thread. These solenoid valves are suitable for most medium to high pressure and open to atmosphere systems. Typical pressure ranges are 0.5 to pressures exceeding 100 Bar. Typical sizes ranging from 3/8 thread to 3 " thread and also flange options to DN500.

Helpful hint: This solenoid valves totally relies on the pressure differential between inlet and outlet ports to open the solenoid valve. 

3/2 way miniature brass solenoid valve 

3/2 Way Miniature Normally Closed Brass Solenoid Valve.

Function: 3/2 way normally closed miniature solenoid valve has 3 ports (1 inlet and 2 outlets) with 2 positions. As a normally closed 3 way solenoid valve when de-energised the inlet port (bottom left) is closed and the outlet port (bottom right) allows flow in one direction through to the top (vertical pipe) exhaust port. When energised the inlet port (bottom left) allows flow in one direction to outlet port (bottom right) but the exhaust port (Top) is closed. The operation of the model shown here on the left is direct acting when the armature within the core tube is moved by the magnetic field of the coil and is itself directly controlling the flow of media and does not require any pressure differentials to operate. (pressure differential is difference between inlet out outlet pressure.) These are typically small compact 3/2 solenoid valves with low to medium power coils up to 20 watts, pressure ranges from 0 to 15 bar sizes ranging from Cnomo sub base mount to 1/8 or 1/4 Thread. Ideal for pneumatic actuator control of larger valves with fail-safe closed position or pneumatic cylinder control applications for fail-safe cylinder retracted. Helpful hint exhaust port 1/4 Male thread typically up through the solenoid coil. NB in most cases flow can be in any direction but if used this way the working pressure differential could be less. 

Miniature brass 3/2 way normally open solenoid valve 

3/2 Way Miniature Normally Open Brass Solenoid Valve.

Function: 3/2 way normally open miniature solenoid valve has 3 ports (1 inlet and 2 outlets) with 2 positions. As a normally open 3 way solenoid valve the inlet port is open allowing flow to the outlet port and the exhaust port is closed. When energised the inlet port is closed and the outlet port is exhausting through to the exhaust port. The operation of the model shown here on the left is direct acting when the armature within the core tube is moved by the magnetic field of the coil and is itself direct controlling the flow of media and does not require any pressure differentials to operate. (pressure differential is difference between inlet out outlet pressure.) These are typically small compact 3/2 solenoid valves with low to medium power coils up to 20 watts, pressure ranges from 0 to 15 bar sizes ranging from Cnomo sub base mount to 1/8 or 1/4 Thread. Ideal for pneumatic valve actuator control of larger valves with fail-safe open position or pneumatic cylinder control applications for fail-safe cylinder extended. Helpful hint exhaust port 1/4 Male thread typically up through the solenoid coil.

Helpful hint: some 3/2 normally open solenoid valves achieve normally open function by using the top exhaust port as the inlet.

NB in most cases flow can be in any direction but if used this way the working pressure differential could be less. 

3/2 way miniature brass solenoid valve

3/2 Way Miniature Universal Brass Solenoid Valve.

Function: 3/2 way universal miniature solenoid valve has 3 ports (1 inlet and 2 outlets) with 2 positions. As a universal 3 way solenoid valve flow can be in any direction with pressure or vacuum inlet from any of the 3 ports without affecting the stated pressure differential parameters. This is an ideal solution as this solenoid valve can be used as normally closed, normally open or as a diverting valve depending on which port is used as inlet.

For example to obtain 3/2 Way Normally Closed Function.

Inlet bottom left Port 1: the solenoid valve will act as a 3/2 normally closed solenoid valve. When de-energised the bottom left Inlet port 1 is closed and the bottom right outlet port 2 is allowing flow through to the top port 3. When energised the bottom left inlet port 1 allows flow to the bottom right outlet port 2, however the top port 3 is now closed.

Now we can change which port is inlet to obtain different functions of normally closed, normally open or diverting as follows.

To obtain 3/2 way Normally Open Function.

Inlet at Top port 1: The solenoid valve will now act as a 3/2 normally open solenoid valve. When de-energised top inlet port 3 will allow flow to bottom right outlet port 2 with bottom left port 1 closed. When energised the top inlet port 3 will now close but the bottom right port 2 will allow flow to bottom left port 1.

To obtain 3/2 way Diverting Function.

Inlet bottom right port 2: the solenoid valve will act as a 3/2 diverting solenoid valve. When de-energised the inlet bottom right port 2 will allow flow to to top port 3, bottom left port 1 closed. When energised bottom right port 2 will flow through to bottom left port 1 but top port 3 is closed.

These are typically small compact miniature 3/2 Brass general purpose solenoid valves with low to medium power coils from 8 watts up to 20 watts, pressure ranges from vacuum to 13 bar, port sizes ranging from Cnomo sub base mount to 1/8 or 1/4 Thread. These are ideal for pneumatic actuator control for larger valves and allow for fail-safe open or fail safe closed actuator positioning using the same 3/2 way miniature solenoid valve but just simply piping it differently, pneumatic cylinder control applications for fail-safe cylinder retracted or extended and in 12 volt use can be used for diesel and vegetable conversion systems for cars and commercial vehicles.

3 way brass universal solenoid valve

3/2 Way Universal Brass Solenoid Valve.

Function: 3/2 way universal solenoid valve has 3 ports (1 inlet and 2 outlets) with 2 positions. As a universal function 3 way solenoid valve the inlet port can be any of the 3 ports depending on application requirements and flow can be in any direction, looking at the the picture on the right see below for piping options to achieve the required function as below.

To obtain 3/2 Way Diverting Solenoid Valve Function.

Using port 2 as the inlet port flow can be diverted to port 1 or port 3 in both directions. When de-energised flow will be port 2 to port 1 in both directions with port 3 closed. When energised flow is port 2 to port 3  in both directions with port 1 closed.

To obtain 3/2 Way Normally Open Solenoid Valve Function.

Using port 1 as the inlet port. When de-energised flow will be port 1 to port 2  in both directions with port 3 closed. When energised port 1 will close with port 2 allowing flow to port 3 in both directions.

To obtain 3/2 Way Normally Closed Solenoid Valve Function. 

Using port 3 as inlet port. When de-energised inlet port 3 will stay closed and port 1 will allow flow to port 2 in both directions. When energised port 3 will allow flow to port 2 in both directions but port 1 will be closed.

Ideal for large bore pneumatic valve actuator control or large bore pneumatic cylinder control in any configuration of normally closed or open function or simple flow diversion for high flow pneumatic process systems. Port sizes from 1/4 to 1/2 thread, pressures from 0 to 10 bar, optional manual reset, manual override function and ATEX Hazardous area EEx d IIC T6 coil.

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