Several types of valves are used in the petrochemical industry to control or modulate the flow of oil & gas products, change the direction of flow of the fluids, regulate the process pressure, or protect the piping system. Despite serving different functions, most valves consist of similar parts, which include an outer shell, wetter parts or “trim”, bonnet, stem, lever, and an actioning mechanism.
The materials used to manufacture a valve can either be cast metal or forged metal depending on the process conditions, i.e., pressure and temperature. Valves can be manually operated by levers, wheels, or gears, or actuated using hydraulic, electric, pneumatic actuators.
Types of valves by design
• Gate: Most commonly used in the petrochemical industry, gate valves are linear motion bi-directional valves to fully start or stop the flow of fluid.
• Globe: Used to throttle the fluid flow, globe valves are used to create a pressure drop in the pipeline.
• Check: Check valves prevent the backflow of fluid in a pipeline, protecting the equipment required to manufacture oil & gas products.
• Ball: Ball valves are quarter-turn shutoff valves used to start or stop the flow of fluids using a built-in ball that rotates inside the valve body.
• Butterfly: Highly versatile, butterfly valves are used to modulate or control the flow of fluid in a pipeline. They are simpler in construction and available in two types, i.e., concentric, or eccentric.
• Y-Strainers: While not particularly a valve, Y-strainers are extremely important components in the petrochemical industry that filter debris and protect downstream equipment.
In the production of oil & gas products, the globally accepted design standard is the ASME valve standard B16.34 and all valves must comply with the specifications. Each valve is tested under controlled conditions to ensure maximum performance and eliminate security risks.
