Everything You Should Know About Solenoid Valves
The hydraulic system of gas and oil firms must be in its best shape to deliver maximum productivity. By choosing the suitable hydraulic solenoid valve, you can ensure the consistent performance of the system. Often solenoid valves are confused with electro-controlled valves. Electrical systems power electro-controlled valves, which can also be dissociated from the valve’s body, but you can’t dissociate solenoid valves from the powering system.
In addition to the working mechanism, you must thoroughly understand various other aspects before selecting solenoid valves. Check the guide below that mentions all the essential details to help with your purchase.
What are solenoid valves?
Solenoid valves are electromechanically operated components that use electric current to create a magnetic field and control the flow rate in the air or fluid-powered mechanical systems. These are appropriate for gas, oil, air and water control applications.
The automatic operation of solenoids is highly convenient to end users and engineers as they can be installed anywhere and don’t require manual supervision.
What are the uses of solenoids?
You can get different models of solenoids designed for different applications and involving various media like
- Compressed air
- Cold and hot liquids
- Natural oil, mineral oil and other oils
- Combustible and aggressive gas
- Aqueous solutions
You see the usage of solenoid valves in various domestic appliances, and some of the typical examples are
- Water flow and heating systems
- Lawn sprinklers
- Car washes
- Air conditioning and refrigeration
- Pressure pumps
- Top-up controls and swimming pool drainage
What are generally open and normally closed solenoid valves?
The powered state of solenoids is categorised into: normally open and normally closed.
A normally open valve gets closed with the energising of the coil allowing the media, especially non-corrosive liquids, air and water, to flow through the system.
Normally closed solenoids use a spring for pressing the plunger tip against the orifice’s opening. This process ensures that the media doesn’t enter the orifice till the plunger gets lifted by the coil’s electromagnetic field.
Do you need a pilot-operated or a directed operated solenoid valve?
A pilot-operated solenoid valve works by creating a pressure difference between downstream and upstream media. Therefore, you can use it only in one direction. Also, the coil that gives the closing or opening signal requires very less electrical power.
These valves are ideal for high flow applications that ensure that the pressure difference between the outlet and inlet of the valve is adequate for the operation.
Direct-operated solenoid valves don’t require pressure difference for operating as the coil acts on the valve or diaphragm. However, these valves require a lot of electrical power and are best for applications requiring low flow rates.
When do you need solenoid valves?
It would help if you had a solenoid valve to control the gas or liquid flow, like during opening or closing a circuit, mixing liquids and gases or dosing products.
The applications may range from controlling a standard process valve to any specific valves like emergency stop valves or fire system valves. An advantage of solenoid valves over traditional valves is their fast response time. You can use them in the following applications:
- In irrigation systems: The low response time of the valve helps save a lot of water.
- In compressors: In the starting phase, the valve discharges the compressor to reduce the torque.
- In some specific cases: If the failure of solenoid valves impose risk on the operator, you can use double-body valves. Generally, these are 3/2way solenoids with a dual valve system compensating for a failed valve.
The sheer range of solenoid designs available in the market can overwhelm you. But don’t forget to check the critical requirements like the temperature, mounting type, pressure, media compatibility and flow rate. Also, go through the manufacturer’s guidelines for safe ratings to ensure that your operating parameters match the specified ratings.