What is a valve?
A valve is a device that is designed to regulate the flow of liquids, gases, or any substances.
What is a gas valve?
A gas valve is a tool for controlling the flow of gas. The volume of gases that can pass through pipes is controlled by opening or closing an aperture. The valve manages the gas flow by stopping and beginning, modifying the amounts, regulating the direction, controlling pressure, or relieving pressure.
Every environment is unique. Some of them are very corrosive. Others work simultaneously while constantly under pressure. These variations have led to the development of numerous distinct types of valves over the years. Each type of valve has benefits and drawbacks of its own. Understanding the various types and applications within the gas and oil industry is necessary for successful operation and application.
Which valves are used to control gas flow?
Valves are a crucial aspect of piping applications in every sector of the oil and gas industry, making the process run more smoothly. There are many different types and classifications of valves, but here is a list of suitable valves for the oil and gas business.
In this article, we are going to discuss which valve is best for controlling the flow of gas in industries. They are
- Butterfly Valves
- ARC Valves
- Ball Valves
- Globe Valves
A butterfly valve is used to control, halt, and restart the flow. This quarter-turn rotary motion valve rotates the handle at 90°, allowing for both a complete close and a start. It enables it to be used in the oil and gas business. Butterfly valves are used to adjust several types of media that have a low-pressure loss. The valve features an actuator and is appropriate for usage anywhere due to its tiny thickness. These valves are useful in large pipes since they are available in greater sizes. These valves provide great reliability and require minimum maintenance due to their rapid open and closure operations.
Why Butterfly Valves?
Butterfly valves are small and they require less material and less construction effort, butterfly valves are typically less expensive than gate valves. They are also simpler to operate against imbalanced water pressures. They immediately open and close pneumatically when activated.
Advantages of Butterfly Valves
- Butterfly valves are extremely trustworthy and require little maintenance because of their high level of precision, which makes them ideal in industrial applications.
- They have the ability to regulate flow.
- They can be inserted or removed without causing any damage to the pipe network.
Disadvantages of Butterfly Valves
- Butterfly valves lack tight cut-offs.
- Regardless of the setting, this may result in a pressure switch across the valve.
ARC or ARV valves
These valves, which stand for ‘Automatic Recirculation Valve’ and ‘Automatic Recirculation Control,’ are multi-functional, but their principal purpose is to ensure that a pre-determined minimum flow is maintained through the centrifugal pump at all times.
Because centrifugal pumps are frequently overheated, it is critical to maintaining the minimum flow; otherwise, dry valves mean irreparable damage.
Why ARC Valve?
- A non-return function in the main line prevents the medium from flowing backward to the pump
- An automatic bypass control ensures that a minimum flow is permitted to return to the pump during periods of low demand
- Pressure let-down functionality ensures that the recirculating medium is maintained at the proper pressure and flashing and cavitation are prevented.
Ball valves are on/off switches with a quarter-turn action. The flow of liquid or gas media is controlled by a pivoting ball in the middle of the valve.
The turning ball is called a rotary ball, and it has a hole (a bore) in the middle. To open or close the valve, a stem on the top of the ball rotates. The stem can be turned manually or automatically.
Why ball valve?
Ball valves are a fantastic choice because they don’t clog easily and are among the easiest valve types to maintain. Ball valves can also be purchased in three-piece designs, which include a body and two end caps.
Advantages of Ball Valves
- They have a compact and low-maintenance design that does not require lubrication.
- They are the most cost-effective of all valves.
- The major benefit of ball valves is that they have poor throttling characteristics, which can easily erode a ball valve’s seat.
- It is leakproof as well as it opens and closes rapidly
Disadvantages of Ball Valves
- It is not ideal for permanent throttling.
- In residual fluids, the particles collide with and adhere to the surfaces. This may cause leakage, abrasion, and other issues.
Globe valves are commonly used in pipelines to control the flow of more viscous fluids such as oil and gas. They are suitable for on/off operations as well as flow rate control. The distance between the lift plug and the valve seat governs flow rate control in this type of valve. Because of their S-shaped channel, globe valves have a bigger pressure drop than many other types of valves.
Why Globe Valve?
A valve can be used to completely stop the flow of fluid as well as to regulate pressures or flow. It may occasionally be used as a check valve or a pressure relief valve. The globe valve has a significantly higher-pressure loss in the fully open position when compared to a gate valve or ball valve.
Advantages of Globe Valves
- Although the globe valves are throttling, the full-closing behaviour is satisfactory.
- The time between opening and closing is shortened.
- The seating surface approach for body rings is simplified.
- They can function as a check and stop valves.
- They’ve got a positive shut-off.
Disadvantages of Globe Valves
- Increased pressure loss
- Globe valves require greater effort or a high torque actuator to close under high pressure.
What are the criteria to consider while choosing valves to control the gas flow?
- Temperature range of gas.
- Minimum and maximum flow required.
- Type of gas to be controlled.
- Minimum and maximum inlet and outlet pressure at the control valve.
- Pressure drop across the valve is expected during normal flowing conditions.
- Inlet and outlet pipeline size and schedule of pipe.
- Application Conditions
- Maintenance Requirements