Different types of valves used in Oil & Gas Industry

VALVES BY BODY MATERIAL

CAST (the body is obtained by casting steel). The main casting materials for valves are listed in this article.

FORGED (the body is manufactured by forging steel)

VALVES BY TYPE OF ACTUATION

MANUAL: the valve is operated manually, via levers, wheels or gears;

ACTUATED: the valve is actioned via electromechanical devices, called actuators, that may be electric, pneumatic, hydraulic & gas over oil

VALVE BY DESIGN

GATE VALVE: This type is the most used in piping & pipeline applications. Gate valves are linear motion devices used open & close the flow of the fluid (shutoff valve). Gate valves cannot be used for throttling applications, i.e. to regulate the flow of the fluid (globe or ball valves should be used in this case). A gate valve is, therefore, either fully opened or closed (by manual wheels, gears or electric, pneumatic & hydraulic actuators)

GLOBE VALVE: This type of valves is used to throttle (regulate) the fluid flow. Globe valves can also block the flow, but for this process, gate valves are preferred. A globe valve creates a pressure drop in the pipeline, as the fluid has to pass through a non-linear passageway.

CHECK VALVE: this type of valve is used to avoid backflow in the piping system or the pipeline that could damage downstream apparatus as pumps, compressors, etc. When the fluid has enough pressure, it opens the valve; when it comes back (reverse flow) at design pressure, it closes the valve – preventing unwanted flows.

BALL VALVE: A Ball valve is a quarter-turn valve used for shut-off application. The valve opens & closes the flow of the fluid via a built-in ball, that rotates inside the valve body. Ball valves are industry standard for on-off applications & are lighter & more compact than gate valves, which serve similar purposes. The two main designs are floating & trunnion (side or top entry)

BUTTERFLY VALVE: This is a multipurpose valve, cost-effective, valve to modulate or open/close the flow of the fluid. Butterfly valves are available in concentric or eccentric design (double/triple), have a compact shape & are becoming more & more competitive vs. ball valves, due to their simpler construction & cost.

PINCH VALVE: This is a type of linear motion valve that can be used for throttling & shut-off application in piping applications that handle solid materials, slurries & dense fluids.  A pinch valve features a pinch tube to regulate the flow.

PLUG VALVE: Plug valve is classified as a quarter-turn valve for shut-off applications. The first plug valves were introduced by the Romans to control water pipelines.

SAFETY VALVE: A safety valve is used to protect a piping arrangement from hazardous overpressures that may threaten human life or other assets. Essentially, a safety valve releases the pressure as a set-value is exceeded.

CONTROL VALVE: these are valves to automate multiple petrochemical processes.