Lubricated Plug Valves: How They Work and How to Select One

Choosing the right valve is important for keeping fluid systems running smoothly. Lubricated plug valves are popular in industries like oil, gas, and chemical processing. This is because these valves are durable and easy to maintain.

In this blog, we’ll explain how these valves work. The post will provide you with tips on how you will choose which one suits your business and industry needs. Whether you sell them or use them in your operations, knowing their benefits can help you make a smart choice.

What Are Lubricated Plug Valves?

Lubricated plug valves utilize lubrication to create a seal between the plug and the valve body. The plug refers to a cylindrical or conical component that rotates within the valve body. Its main function is to control the flow of fluids.1

Lubricated plug valves require a special grease. This is injected between the plug and the valve body. This grease helps reduce friction, making it easier to open and close the valve.

Lubricated plug valves are commonly used in systems that require regular operations. Although they have straightforward design, it enables them to be durable. This feature makes them less likely to suffer from wear and tear, even in demanding environments.

How Do Lubricated Plug Valves Work?

The primary mechanism of lubricated plug valves revolves around the plug.² This rotates 90 degrees to either block or allow fluid flow. We explained a step-by-step breakdown of how they work below:

Valve in Closed Position

When the plug is in the closed position, it blocks fluid flow. The lubrication creates a tight seal between the plug and valve body, preventing leaks.

Valve in Open Position

When the plug rotates 90 degrees to the open position, the hollow passage inside aligns with the pipeline, allowing fluid to flow freely.

Lubrication System

A key feature of these valves is their lubrication system. Grease fittings let operators inject sealant grease, maintaining the seal and ensuring smooth operation. Lubrication also helps prevent corrosion and wear.

Pressure Balance

The Inverted Pressure Balance Lubricated Plug Valve has a pressure balance system, allowing the valve to operate with low torque. This makes it easier to open and close, even under high-pressure conditions.

Which Type of Plug Seals Lubrication?

There are two main types of plug seals in lubricated plug valves:

Grease-Sealed Plugs

In this design, a thick grease is injected between the plug and valve body. The grease helps create a tight seal and ensures smooth valve operation. This type of seal is ideal for applications with high pressures or aggressive fluids. It offers a high level of durability and corrosion resistance.

Metal-to-metal seals with Lubrication

This type of seal uses a metal-to-metal contact between the plug and the valve body, but lubrication is still used to reduce friction. Metal-to-metal seals are commonly used in high-temperature settings where softer sealing materials might break down.

How to Select the Right Lubricated Plug Valve

There are several factors to consider when selecting a lubricated plug valve for your system. Here are the key things to look at:

Fluid Type

Lubricated plug valves are ideal for handling corrosive, high-temperature, high-pressure, and abrasive fluids. If you’re working with aggressive media, ensure the valve can withstand these harsh conditions. Lubrication provides an added layer of protection, preventing damage to the valve and ensuring a reliable seal.

Valve Size and Pressure Rating

You should choose a valve that matches the size and pressure rating of your system. The Inverted Pressure Balance Lubricated Plug Valve from PANS Valve is available in a wide range of sizes. It meets API 599/API 6D standards, ensuring top performance in demanding conditions. It also has a pressure rating that can handle various industrial applications.

Material Compatibility

It’s critical to match the valve’s material to the type of fluid it will handle. For corrosive fluids, consider valves made from plastic or with specialized coatings to resist damage. Make sure the valve material can withstand the chemical composition and physical properties of the media for long-term reliability.

Sealing System

Look for a valve with a reliable sealing system. The PANS Valve lubricated plug valve features an oil groove between the valve body and the sealing surface. This allows the seal grease to be injected and ensures an effective seal.

Size and End Connections

Ensure that the valve size matches your pipeline’s dimensions to maintain smooth fluid flow. Additionally, check the valve’s end connections. It could be threaded, welded, or flanged. This step ensures compatibility with your existing pipeline for seamless installation. The step is also crucial for minimizing disruptions during setup and ensuring a secure fit.

Ease of Operation

Make sure the valve is easy to operate. Reputable manufacturers produce valves that are designed with a bolt cover and a flip-chip balanceable pressure structure. This construction ensures light and easy operation. Even under high pressure, the valve can be operated with minimal effort.

Maintenance Requirements

Lubricated plug valves are generally low maintenance. It is essential to select a valve that allows easy lubrication. The grease injection system in the PANS Valve plug valve makes maintenance simple. It ensures the valve stays in optimal condition.

Why Choose the PANS Valve Lubricated Plug Valve?

When it comes to high-quality lubricated plug valves, PANS Valve stands out as a leader in the industry. Here are some reasons why:

• Durable Construction: The Inverted Pressure Balance Lubricated Plug Valve is designed with a bolt cover and pressure balance system. It ensures light and reliable operation even under high pressure.
• High-Quality Sealing: It features an oil groove that allows seal grease to be injected. This improves the sealing capability and reduces the risk of leaks.
• Compliance with International Standards: Pans valve meets the API 599/API 6D standards for design and manufacture. They are built to the highest quality.
• Versatility: They are available with flanged ends or butt welding options. The valve can be used in various pipeline systems.
• Proven Track Record: They have over 36 years of experience in valve manufacturing. PANS Valve is known for its reliability and commitment to quality. Their production facilities cover 25,000 square meters, and they produce over 3,000 tons of valves per year.

Conclusion

Lubricated plug valves are essential for fluid control. They are a top choice thanks to their operational efficiency. They are well-suited for tough conditions, including high pressures and extreme temperatures.

As you select valves for your business or operation, you should consider factors such as size, pressure rating, material, and sealing system. Hence, we recommend the Inverted Pressure Balance Lubricated Plug Valve from PANS Valve. 

PANS’ Inverted Pressure Balance Lubricated Plug Valve features advanced options such as pressure balancing, grease injection, and a dependable sealing mechanism. They are renowned for producing high-quality valves that comply with global standards. PANS Valve is a reliable manufacturer.

For those seeking a robust, efficient, and low-maintenance lubricated plug valve, PANS Valve is a superb option.

References

1 Lubricated VS. Non-Lubricated Plug Valves

(https://norgascontrols.com/blog/valves/lubricated-vs-non-lubricated-plug-valves/)

2 What is a Plug Valve? Types, Parts, Uses, How to Choose

(https://www.gmsthailand.com/blog/what-is-plug-valve/)