Solenoids valves are used in a wide range of applications, from industrial machinery, automobiles, to home appliances and systems. A pneumatic solenoid valve regulates the passage of air in a circuit, while a liquid solenoid valve controls the flow of a liquid medium.
The extensive use of solenoid valves is not without a reason. The valves are fast-acting, almost noiseless and accurate, among other advantages.
We picked and described the most common applications.
Most agricultural equipment contain solenoid valves to control a system. You will find them in irrigation devices such as the automatic sprinkler, or motorized farm machines to dose substances.
An irrigation solenoid valve basically controls the flow of water and can be used to operate a sprinkler’s function autonomously.
Other uses include the transmission systems of farm machinery where they’re used to regulate different fluids. You will also find these valves in equipment where they are used to dispense chemicals. Milking machines employ the action of an electromagnetic solenoid valve.
With all these uses, these valve types are among the most common in the agriculture industry, perhaps only comparable to the pneumatic control valve.
Manufacturing Systems
Solenoid valves are used in industries to control machines, dose, mix, or restrict the flow of liquids or gases. As an example, solenoid valves are used in beverage factories to measure the exact amount of drink to be poured into bottles.
The valves can also be used to mix different liquid substances using precise volumes. In automatic systems, solenoid valves are utilized to control the flow of fluid and produce movements.
Automotive Applications
A range of solenoid valves are used in motor vehicle systems. They are usually used to regulate the flow of automotive fluids such as oil, anti-skid brake fluid or even fuel.
In some of these functions, a variable solenoid valve is often utilized. It allows a medium to be controlled instead of shutting it off completely.
A good example of this is when limiting the flow of fuel to the engine to reduce vehicle speed. The fuel solenoid valve is common in countries that have regulatory rules for speed.
Other automobile solenoid valves include the type used to shut off fuel flow and stop a vehicle, the type to drain water from a water fuel separator automatically, and the coolant control solenoid valve in a vehicle’s HVAC system.
Vacuum Systems
Solenoid valves are widely used in vacuum applications. Direct and semi-direct valve types are the most common. They need no minimal pressure levels, which makes them best suited for these situations. A vacuum solenoid valve is usually designed to be leak-free, a necessary requirement in such conditions.
Vacuum applications include the electronics industry where partial removal of air is needed, vacuum manufacturing and automation systems, and vacuum pumps.
Home Heating Units
Heaters use gas or wood to heat up water and distribute it to various fixtures such as the bathroom shower head, kitchen faucet, and other installations. At the heart of the heater’s operation are solenoid valves.
These automatically open and close to let in cold and hot water. The flow rate in the circuit is usually high, which makes a pilot operated solenoid valve the most suitable.
Refrigeration Appliances and systems
An important use of the electric solenoid valve is in refrigeration systems. A refrigeration solenoid valve serves several functions in these units. It prevents high-pressure compressor starts and protects the compressor from fluid hammer issues. The valve also shuts off and opens the passage of refrigerant as required, helping to prevent it from entering the evaporator when the compressor stops.
Car Washing Machines
Car washing equipment delivers high-pressure water and detergent to clean motor vehicles. To mix and rise the water and cleaning solution, these pieces of equipment use a series of automatic solenoid valves.
These valves are usually direct operated types. To protect the valves from the corrosive chemicals in the cleaning solution, manufacturers use nickel-plated brass.
Air Compressor units
An air compressor takes in air and compresses it before taking it to the compressed air reservoir. When air enters the tank, it has to kept under pressure. This is achieved by the use of a solenoid valve.
A compressed air solenoid valve powers up to close the flow of fluid, in this case air, and allows the built-up pressure to remain in the tank.
The compressed air pressure should not remain in the tank for long. When the coil de-energizes, the valve opens and releases the air into the system.
Hot Drink Dispensers
These are machines that dispense coffee, tea, and other beverages. They are usually found in offices and commercial establishments, although some can be used in private places. Hot drink dispensers usually utilize direct acting solenoid valve systems.
The valves open and close in sequence to allow fluids to move through the system.
Water Mixing in a Safety Tap
In places where sanitation is a strict requirement, solenoid valves are used to automatically mix cold and hot water before it comes out of the tap or faucet. Usually, the installations are fitted with a sensor to detect human presence. It can be an infrared sensor or any other device.
Behind the installation are two water solenoid valves. These open simultaneously to let in hot and cold water. The types used are usually pilot operated solenoid valves due to the high flows involved.
Floor Washing Machines
A floor washing machine has to dispense water and cleaning solution at the same time- and in the right amounts. To ensure that, an electromagnetic solenoid valve is utilized for each function.
Because the fluids to be controlled are not under pressure, the valves used are mostly the direct acting types.
Water Metering Devices
These are mechanical devices that regulate the amount of water dispensed. They are used in different places, such as food industries to measure exact water quantities for mixtures. The solenoid valves used in these meters are usually the pilot operated types.
These easily accommodate the high flow rates common in the installations. When system pressures are low, these water solenoid valves incorporate an assisted lift.
Natural Gas Installations and Appliances
Solenoid valves are used in both industrial and home gas systems to open or stop the flow of natural gas. A gas solenoid valve can also be found in the installations that use pneumatic actuators for different functions. Natural gas solenoid valves control the gas flow in domestic gas heating systems, directing when the gas must light up to heat water and when to shut off.
Conclusion
Solenoid valves are a common device in today’s works. They’re used virtually everywhere from automated manufacturing systems, automobiles, refrigeration and AC systems to the pumps and irrigation systems in farms.
Compared to the pneumatic valves or some types of hydraulic valves, they can be found in most home appliances and installations.
In industries and engineering systems, the electromagnetic valve is the most used.
The list of applications is in no way exhaustive, and the examples explained here are the most common.