Precision in Motion: Examining the Working Mechanism of Lubricated Plug Valves

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Plug valves are a crucial component in various industries, ensuring smooth and efficient flow control of liquids and gases. From oil refineries to wastewater treatment plants, these valves play a vital role in regulating the flow within pipelines. There are different types of plug valves available in the market, each designed for specific applications and operating conditions.

In this blog, we will take a closer look at the various types of plug valves and delve into the working mechanism of lubricated plug valves. So, whether you are a professional in the industry or simply curious about the inner workings of these valves, keep reading to expand your knowledge on this essential piece of equipment. Let’s find out with lubricationfaqs!

Types of Plug Valve

1. Lubricated Plug Valve

Lubricating plug valves are a crucial component of many systems because they make it simple to alter various liquid and gas flows. They are composed of a valve body divided into two halves; one retains the plug, which is inserted into a path between the two, and the other has identical geometric ports sealed around it to regulate flow. A reliable seal with little leakage is achieved by applying lubricant to the plug surface, the faces, and the base of the valve.

In these applications, temperature ranges can range widely, from freezing temperatures to high temperature settings like steam service or power plants. At these temperatures, the lubricant must provide thermal stability and offer additional defense against wear on both surfaces during routine usage.

2. Non-lubricated Plug Valve

Because of their effectiveness and dependability, non-lubricated plug valves are becoming more and more used in a variety of industrial, commercial, and residential applications. These devices are substantially lighter and smaller than conventional plug valve types, which makes them perfect for usage in limited spaces. Compared to many other valve systems, non-lubricated plug valves are incredibly resilient and require less upkeep.

These valves can offer many years of dependable operation in a range of situations because to the extra feature of corrosion resistance. The many needs are present in different sectors, from basic plumbing to difficult applications. Furthermore, they are a great option for the majority of valve needs because they can be utilized with practically any type of vehicle, including fuel, water, and natural gas.

3. Eccentric Plug Valve

An effective flow regulator with a meter is the eccentric plug valve. Greater control is possible by simply turning an eccentric plug in place of a traditional globe or gate valve. When used in applications like food processing or environmental monitoring, this device is well suited for tasks that call for precision adjustment and long-term stability.

Silicone gasket technology offers a trustworthy, leak-proof solution because it doesn’t contain any organic or inorganic components that could deteriorate over time. Furthermore, uncomplicated maintenance is possible for the duration of the swivel plug’s service life because to its smooth operation. Overall, consumers that want accurate and trustworthy flow control can profit greatly from eccentric plug valves.

4. Expanding Plug Valve

Plug valves are a crucial part of many processes, and plug valve expansion can result in increased productivity. This kind of valve creates a sealing ring that offers the best flow control with the least amount of pressure loss by using a conical sleeve that expands outwards when pressure is applied to the piston head.

Expanding plug valves enable washers to be held for a longer period of time and open and close more quickly than the majority of alternate solutions. Thanks to their sealing ring design, they also improve system performance by minimizing vibrations and axial movements. The expansion plug valve, which is dependable, effective, and simple to use, is the ideal method of flow control.

How does the Lubricated Plug Valve work?

By injecting a lubricant under pressure between the face and stem base of the stopper, often made up of a base oil and a viscosity improver, lubricating stopper valves can minimize friction and seal ports. Manufacturers of valves advise using lubricants appropriate for process fluids. In most circumstances, valves need to be re-sealed after a few cycles, and in some cases, after each cycle.

Lubricating oil is used to seal the base in order to lessen friction between the valve body and the stopper’s sealing surface. As high-pressure seal oil is poured around the stopper to produce a high-pressure seal, an oil film between the valve body and the sealing surface of the conical stopper confirms the tightness and smooths the opening and closing motion.

A cavity in the middle of the stopper formed by the lubricated stopper valve runs along its axis. A glue pump coupling is located at the top of this hollow, which is blocked at the bottom. An injection coupling-level check valve prevents the sealant from leaking back after it is put into the cavity. Radial perforations in the middle cavity allow sealant to exit and flow into lubricating grooves that run the whole length of the plug’s seat surface.

The pipeline fluid and lubricant need to get along. It must not break down or be washed away by the flow medium because doing so could contaminate the liquid, break the seal between the plug and the body, and cause a leak. The sealant that is utilized also needs to be temperature resistant for the flow media.

Difference between Lubricated and Non-lubricated Plug Valves

The primary distinction between lubricated and non-lubricated plug valves is the former’s usage of a lubrication system to continuously maintain the valve stem and increase the stem’s lifespan. The friction between the valve body and the stopper is reduced by a non-metallic elastomer or thermoplastic liner in non-lubricated stopper valves.

Stopcock valves that can close off a liquid with a bubble can be lubricated or unlubricated. Non-lubricated stopcock valves are less expensive to maintain even if they are less effective in halting or starting the flow of the medium. The non-metallic seating, however, prevents you from using them in high temperature settings.

Difference between Lubricated and Non-lubricated Plug Valves

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In conclusion, this examination of different types of plug valves and the working mechanism of lubricated plug valves has provided a comprehensive understanding of their functions and applications. We have explored the various types, such as sleeved plug valves, lined plug valves, and lubricated plug valves, each with their unique features and advantages.

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