Whenever a liquid media needs to be monitored, regulated, or altered through various piping sections of a system, a control valve is required. Control valves are a crucial component of every piping system. We are the leading ball valve distributor in Nigeria.
There are several types of control valves, such as ball and plug valves, which perform comparable functions and are often interchangeable. As far as overall structure, function, and applications are concerned, they remain unique. Plug versus ball valves is discussed in this guide along with other relevant information that can help people choose the ideal valve type for the desired applications from reputable industrial valve suppliers.
What Is Plug Valve
Plug valves rotate in a 90-degree circle and regulate flow with tapered or cylindrical stoppers. There is a path for the flow to pass through the disc, which is shaped like a plug. When the bore passage is open, it is in the flow. When the stopper is swiveled 90 degrees from the open position, its heavy part restricts flow.
It is used instead of a gate valve when a speedy operation is required. Plug valves are typically used in low-pressure and low-temperature applications. Plug valves with polytetrafluoroethylene (PTFE) body linings are suitable for use with corrosive chemicals.
The ball valve is an on/off mechanism that can be turned a quarter turn. Gas or fluid media flow is regulated by the valve’s movable ball located in its center. A hole is cut in the middle of the rotary ball, which serves as the pivot. On the top of the valve, a stem allows the ball to be swiveled for opening and closing. Using levers or manually, the stem can be swiveled.
In most cases, ball valves are made of steel, bronze, iron, brass, or PVC. Ball valves can have multiple ports or apertures in them. The two-port ball valve use for conventional on/off control and retains two ports. In applications where multiple media sources are required or media must diverge in different directions, multi-port valves are used (such as 3-way valves, 4-way valves, etc.).
Plug Valve Vs Ball Valve: Major Differences
Find out what the main differences are between ball valves and plug valves.
Different Types of Valve
Below are the differences between plug valves and ball valves.
Plug Valves
The majority of plug valves are full bore, especially rectangular port valves. In low-pressure applications, round port and diamond port valves can also use. Lubricated plug valves and non-lubricated plug valves are available.
There is a lubricant chamber in the plug of lubricated plug valves that maintains lubrication at all times. Lubricated plugs move more smoothly, experience less friction, and are corrosion-resistant. High-temperature applications can handle lubricant plug valves.
Ball Valves
Among the many applications of control, the valve is the ball valve. Depending on their construction and purpose, they are available in a variety of sizes and shapes. As a result, they are currently among the most commonly use valves in the pipe industry. A ball valve can have a full bore or a reduced bore.
Unrestricted medium flow is possible with full bore ball valves. Reduced bore or reduced port valves restrict media flow since they have a bore smaller than the pipeline diameter. There are two types of ball valves: float valves and trunnion valves. When a bi-directional shut-off require, floating ball valves use. Generally, trunnion-mounted ball valves use for high-pressure and high-temperature applications. We are the leading ball valve distributor in Nigeria.
Structure Of The Valves
Plug Valves
Plug valves have conical tapering or cylindrical discs that regulate the flow of liquid through one or more sideways-moving passageways. When the valve is open, the hollow tunnel aligns with the flow, allowing fluid to flow freely. An alignment of the plug restricts the flow after a 90-degree rotation shuts the valve.
Plug valves are compact, straightforward devices that alter the flow of media by cutting or dispersing it. Some plug valves can function at high temperatures, but their primary applications are at medium or low pressures and low temperatures.
Ball Valves
An altered plug valve, a ball valve has a spherical disc and a circular bore channel. In a disc, there is a hole call a port. When the port aligns with the dual ends of the valve, the medium seeps through the valve. If the port vertically aligns with the ends of the valve, the flow ceases.
The small structure, simplicity of use, and compatibility with water, acids, natural gas, and solvents make ball valves useful for a variety of systems. Ball valves perform well even in extreme operating environments like hydrogen peroxide, oxygen, methane, or ethylene. A traditional gas shutdown ball valve is the best suite for opening and closing, while a more sophisticated or customized model can also control flow and throttle.
Function
Plug valves and ball valves are quarter-turn valves that operate with a rapid 90-degree rotation of the actuator. Sealing and shut-off procedures are their main functions. As compared to a ball valve, the sealing surface of a plug valve is significantly larger. This leads to better sealing properties, but it also involves more torque and works during operation.
As a result of their torque-free operation and lightweight design, ball valves are easier to regulate than plug valves. Despite the possibility that their tiny sealing surfaces may result in poor sealing performance, chemical sealants and seal injections have helped address this issue.
Also, read “Most Common Valves used in Oil & Gas Refineries You Should Know”
Construction
Both plug valves and ball valves have bored discs in the middle. A ball valve has a spherical disc with a hollow center. Plug valves consist of conical or cylindrical discs with apertures drilled into them. A plug valve uses a larger disc or ball than a ball valve, enabling it to provide a tighter shut-off than a ball valve. Furthermore, plug valves are more compact than ball valves. Due to their small footprint, plug valves can easily position in smaller departments.
Distinct Principle
The ball valve evolved from the plug valve. Depending on the “plug” used, it can be either a plug or a ball with a circular through hole or channel running through its center. When rotated by 90 degrees, the ball should appear as a sphere at the intake and outlet to stop the flow.
There is packing between the plug and the body that seals the upper components of the plug valve, the conical plug, and the body surface created by the conical pressure. As plug valves typically do not retain bonnets and the handles expose outdoors at the end, they are easy to operate and inexpensive.
Control Capacity
Many types of actuators can use to operate ball valves, including manual, pneumatic, hydraulic, electric, and others. Although they operate under high pressure, they are easy to open and shut down.
It is possible to open and close plug valves manually or electrically by using actuators. Although pneumatic actuators are relatively expensive to install, they can also use to regulate them. Since high-pressure plug valves have a substantial amount of torque, they may be difficult to open and close. As a result, plug valves rarel use in larger applications.
Cost
Plug valves are considerably less expensive than ball valves. The bushing completely covers the “plug,” which prevents wear on the valve body and plug. It is possible to update and repair the valve by changing the bushing and top seal, which can withstand 300°C of continuous use.
Besides the flange and top face, the plug valve is cast in a single step. The internal body, however, does not need to process. Plug valves have a clear cost advantage over ball valves when compared.
Lifespan
Generally, ball valves last longer than plug valves. Plug valves have a larger surface area in contact with the medium and designe to handle greater torque. It indicates that the valve has deteriorated more and is more susceptible to corrosion.
There are unique features of ball valves that prevent the medium from constantly contacting the disc. While there are more moving parts, the low torque ensures that it will last longer with little to no wear and tear.
Check Valves
It is also possible to customize plug valves, although it is only partially feasible. Because of their basic design, which offers little potential for development, it’s possible. Multi-port plug valves come in a variety of sizes, ranging from two to five ports.
It is important to use multiport valves carefully since they might not provide a very tight shut-off. Additional plug valve modifications, such as electric or pneumatic actuators or anti-friction components, are relatively expensive.
Ball Valves
The adjustability of ball valves is significantly greater than that of plug valves. The reason is that there are so many types of ball valves available on the market. In addition to unidirectional and bidirectional ball valves, there are also multidirectional ball valves.
The pieces can retain in one, two, or three pieces with one or more ports. There are split-body, top-entry, end-entry, and side-entry ball valves available. Additionally, double-blocking and double-bleeding ball valves are available.
Maintenance
To operate effectively, both ball valves and plug valves require routine maintenance. As plug valves have fewer moving parts and simpler construction, they are relatively easy to maintain. After removing and cleaning the plug, you can easily reach the remaining valve body to clean it.
It is more difficult to clean ball valves because the ball or disc burie deep within the valve. Over time, the ball valve’s body chamber may accumulate significant debris, making cleaning and maintaining it more difficult.
The operation of plug valves is less expensive than that of ball valves. In a plug valve, the plug fits underneath the bushing to prevent wear on the valve body and plug. Only the top seal and bushing need to replace to maintain the valve’s optimal function.
Are Plug Valves Better Than Ball Valves
Ball valves cannot replace plug valves, but plug valves can replace ball valves. Plug valves are easier to use. A ball valve, on the other hand, has a space between the body and the ball. When the ball valve place and shut down, some medium remains in the void. It is necessary to clean the medium before resuming the operation of the machine. In chemical and food manufacturing facilities, it is a common problem. In situations where a prolonged stop period makes it impossible to thoroughly clean the medium, ball valves become useless.
Flow permits through a plug valve since it has a full port. Ball valves, however, can have a full port or a limited port.
Plug Valve Vs Ball Valve: How To Choose
When choosing between the ball valve and plug valves, it is important to understand the type of valve application.
When To Acquire Plug Valves
Plug valves use in liquid applications such as vapor, air, gas, and hydrocarbons to ensure bubble-tight shutoff. Plug valves commonly use in slurries, sewage, and mud applications because of their large surface area and unrestricted flow.
Plug valves with strengthen seals use when working with corrosive or hard materials. Their straightforward operation and anti-corrosion properties make them the most reliable shutdown option in sensitive applications.
When To Acquire Ball Valves
As well as use in generator skids, compressor skids, gas feed lines, crude oil plants, LNG plants, industrial gas processing plants, polymer plants, field gas plants, hydrocarbon processing, oil refinery feedstock lines, tank farms, separator skids, and automated processes, ball valves have a wide range of applications.
In cryogenic, subterranean, and subsea applications, high-pressure ball valves are essential. The use of stainless steel ball valves is also essential for brewing, desalination, feedwater, cooling water, and petroleum refining.
