Industrial valves are devices used to control the flow of liquids, gases, and slurries. These valves are designed to withstand tremendous pressures from liquids or gases and can last for years. High-duty industrial valves are often used in utility plants, including water and oil & gas facilities to control fluid flow by opening, closing, and partially obstructing pipes and other channels.
Put simply, industrial valves are mechanical devices that control the flow and pressure of fluids within systems and processes. Usually, they come designed with unique features and applications and, thus, can be of different types.
Choosing the Right Valves for Different Purposes: Know the Major Types
Check Valves: Best for Controlling Backflow in Fluid Systems
What are Check Valves?
Check valves are also known as non-return valves because they allow for only a one-way flow of water, air, stream, or other liquids and gases. These valves prevent the reverse flow of fluids, which could damage industrial equipment and processes if it happens and shut down pumps and compressors. The direction in which the fluid or gas can flow is called the free flow direction; the direction in which fluid is prevented from flowing is called the checked or non-return direction.
For industrial applications, check valves are commonly used to protect pumps in liquid and gas systems from backflow mostly without human interaction, thanks to their simple design and minimum pressure loss. A common application for a non-return check valve is in pump inlet and outlet ports.
Where can Check Valves be Used?
One of the major application areas for check valves are in pipelines of sewage and desalination systems where the backflow of sewage and wastewater respectively into the system needs to be checked. They can also be used to maintain the pressure of the water system when the pumps cut off, and to prevent the medium in the container from being discharged.
Check valves are also recommended in certain special circumstances. For example, backflow of condensate from the lifting pipeline is one of the main causes of water hammer in the condensate recovery line. If the trap’s output is recycled into the same condensate collecting line, a check valve must be installed to prevent condensate water from flowing back to non-running equipment and causing water hammering.
Relief Valves
What are Relief Valves?
A relief valve, commonly known as a pressure relief valve (PRV) is a device that releases or restricts pressure in pipes to maintain pressure balance and prevent build-up. It is sometimes incorrectly referred to as the pressure safety valve.
A relief valve is a mechanical device which allows a gas or liquid to escape from a section of a fluidic system when the pressure exceeds a predetermined limit. The primary function of a relief valve is to protect the equipment during an overpressure event or to increase pressure during a drop. The location of relief valves within a system are decided by process engineers based on PRV requirements and some general guidelines.
Where can Relief Valves be Used?
Relief valves are one of the most economical industrial application solutions, and they may be utilised in all types of gas and liquid applications, as well as high pressure and temperature applications. Usually, relief valves are used in all vessels as a mandatory safety barrier to eliminate pressure hazards cost-effectively.
Relief valves are also utilised in heat-exposed sections of cool liquid lines, on discharge sides of positive displacement pumps, compressors, and turbines, as well as in vessel steam jackets and low-pressure storage tanks that are not normally constructed for vacuum. Process engineers may also install relief valves in particular instances, such as places where formal hazard detection methods indicate and piping systems prone to overpressure and process control failure.
Another possible application, is to use as a thermal relief valves, it is intended to relieve a very small amount of fluid due to thermal expansion within a trapped volume. In this case, it is important that the valve is optimized for very low flow rates. For example for this type of valve is the parking brake system of an aircraft. External temperatures during flight can get very low, while ground temperatures are potentially much higher. While the aircraft is parked the fluid in the parking brake system will expand due to the temperature increase. A thermal relief valve can be used to relieve the fluid when it expands, decreasing pressure to avoid the potential failure of the parking brake system and the dangerous situation of the aircraft rolling unexpectedly.
Flow Control Valves
What are Flow Control Valves?
Flow control valves are used in industrial applications to control the flow rate of the medium. Simply put, these valves can regulate the flow of hydraulic fluid or compressed air and are usually versatile enough to support high pressures and temperatures.
Throttle valves and flow regulators are the two main types of flow control valves. Throttle valves limit the flow of compressed air in one direction and are employed to control volumetric flow rates. The restrictor narrows the cross-section of the line, resulting in localised flow resistance. The bigger the pressure difference with a throttle valve, the greater is the differential pressure at the throttle point, and the higher the volumetric flow rate.
Flow regulators on the other hand, often known as volume control valves, work with pressure compensation. These valves ensure that the predetermined volumetric flow rate remains constant even if the pressure across the valve varies.
Where can Flow Control Valves be Used?
One of the most typical applications for a flow control valve is to control the speed of motors or cylinders in a system. Flow control valves are widely used in oil and gas, materials handling, food processing, automated manufacturing and warehouse equipment, chemical storage, and even residential applications due to their variable performance parameters.
What to Look for when Choosing the Best Industrial Valve for Your Facility?
The size, design, function, and functioning of industrial valves vary widely. Some provide tight leakage protection, while others are excellent throttlers. Understanding each valve makes knowing how to apply them in the industry much easier. At Winova, we offer various micro and precision micro-hydraulics products and electro-fluidic systems for industrial applications. Get in touch with us right away to learn more about what we do and how we can help.
