The plug has a through slit which remains in-line with the flow in the open condition. sulphur and hydrogen fluoride), since they do not have a body cavity in open communication with the flow when switching, where fouling liquids could be trapped or solidify, potentially jamming the valve. Ball valves may have less impressive sealing abilities but they are easy to operate and can be easily scaled up for larger applications. Reduced bore or reduced port valves restrict the flow of medium as the size of the bore is less than the diameter of the pipeline. Ball and plug valves are very similar in terms of their basic function and application. Non-lubricated plug valves are used instead of lubricated plug valves, where maintenance needs to be kept to a minimum. Damaged seating can sometimes be restored in service using the sealant facility.
The plug can be cylindrical or tapered and has a variety of port types. The three main types of non-lubricated valves are: fully lined, elastomer sleeve and, lift-type plug valve.

These valves are torque seated. This means the valve has more wear and tear and is more prone to corrosion. Buna-N Coated Cast Iron, EPDM and 316 SS Stainless Steel 175 psi Flanged Gear Operator Plug Valve. The cylindrical or conical plug in the valve has a larger surface area so it can provide a better seal. They can be used in special services (e.g. They are easy to open and close and require very little force even when operating under high-pressure conditions. Source: https://www.sciencedirect.com http://www.wermac.org. Plug valve, slim valve for on/off control but with some pressure drop. Your email address will not be published. These valves are torque seated. Industrial-Plug-Valve. Stainless steel ball valves are used in cooling water, feedwater, petroleum refining, desalination, and brewing. They are also extensively used on gas pipeline systems as bypass valves to mainline ball valves, blow-down valves on valve stations and kicker valves. Like for soft-seated ball valves, non-lubricated plug valves are limited by temperature and chemical compatibility of the non-metallic materials used. Round port and diamond port valves can have reduced bores as well but they can only be used in low-pressure applications. The plug bore is normally reduced but full port is available for slurry applications with high solid content where these valves are particularly more suitable than other types. Plug valves are used for a condition where a quick ON / OFF and/or bubble tight closure is required. When the plug is turned, the solid part of the plug blocks the flow, hence closing the valve. A plug valve is named so because it features a conically-tapered or cylindrical disc that resembles a plug. The major difference, though, is how the disc looks like.

Valves can be categorized also based on their function

These valves, although expensive, give a true double block and bleed function in a single valve, and are ideal for preventing product contamination (e.g. However, ball valves have a greater margin for customization than plug valves. 3. Non-Lubricated Plug Valve. Corrosive media.
Ball valves are less heavy than plug valves. Milliken Valve Series 601 8 in. Full port valves are considerably more expensive than reduced port and normally not used in hydrocarbon applications. Control valves need regular maintenance to keep working effectively. All other kinds of customizations on a plug valve like installing electric or pneumatic actuators or adding anti-friction components are very expensive. The valves are however heavier and more expensive than ball valves. Call for Pricing. Plug valves are available in either a lubricated or non-lubricated design. Your email address will not be published. Also known as plug valves, these are often used as a mainline shutoff in natural gas and propane pipelines. This is the reason why they are one of the most popular valves used in the piping industry today. In most designs, the plug can be lifted from the seat through manual adjustment of a jacking screw. Plug valve ends can be flanged, hub type or butt weld. Control valves are an essential part of any piping unit. Though care must be taken while operating multiport valves as they might not provide a very tight shut-off. The range of plug valve applications is broad, and the Flowserve portfolio reliably addresses the vast majority of requirements. When the port is perpendicular to the ends of the valve, the valve is closed and the flow of medium stops. 4. Control valves are an essential part of any piping unit. Plug valves are easier to maintain as the plug can be easily removed and cleaned. In fact, one of the main criticisms of ball valves is that over time, the body cavity of the valve accumulates particles from the medium that is then difficult to remove. Though it has more moving parts, the low torque means less wear and tear. Also let us know if you have any questions! Ball valves are difficult to maintain as the ball or disc is located deep inside the valve and cannot be easily accessed. This valve consists of a plug which can be either cylindrical or conical in shape. We use cookies to enhance your experience in case of repeated visits. Plug valves are also smaller in size as opposed to a ball valve. When the port is in line with both ends of the valve, the valve is open and allows medium to flow through it easily. The basic function of these valves is to manage the flow of medium through different piping areas of a system.

As the plug contacts or “cams” into the seat, the seating surfaces dynamically align to achieve shutoff. Their versatility makes them a popular choice for turbine skids, gas feed lines, compressor skids, crude oil plants, generator skids, polymer plants, separator skids, LNG plants, field gas plants, industrial gas processing plants, tank farms, oil refinery feedstock lines, hydrocarbon processing, and automated process applications. Ball valves are extremely versatile control valves. Non-lubricated plug valves contain a polymeric body liner or a sleeve, which is installed in the body cavity. If the plug 90° is rotated from the open position, the solid part of the plug … Furthermore, their sealing capabilities can be enhanced with added technology and mechanisms. To see availability for this product, personLog In or Get Online Access. You can find multi-port plug valves in the market that start from 2 ports and go all the way up to 5 ports. We also use third-party cookies that help us analyze and understand how you use this website. Of all valves, the plug type, ball and the globe type has some similarities. For the globe valve, it is cylindrical.

Source: https://blog.projectmaterials.com. The two key reference specifications covering this type of valve, for petrochemical applications, are the. The plug has no contact with its seat until it turns within a few degrees of the shutoff position. It is mandatory to procure user consent prior to running these cookies on your website. This valve type can also be referred to as rotary globe. This sleeve reduces any friction between the plug and the body. Lubricants shall contain base oil and a viscosity improver like amorphous or fumed silica. In the open position, the plug-passage is in one line with the inlet and outlet ports of the Valve body. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. These valves are not torque seated. For double block and bleed non-piggable upstream applications, where space and weight is a consideration, double isolation plug valves may be considered instead of two valves in series. They are available with resilient plug facings for drip tight bi-directional shutoff, or metal plugs that provide shutoff per ANSI/FCI 70-2 Class IV. There are so many types of control valves to choose for your needs is a daunting task. This also gives easy access to the rest of the valve body so it can be maintained without much hassle. Required fields are marked *. Non-Lubricated Plug Valve Read on to find out more.

Ball valves, on the other hand, provide torque-free operation. This website uses cookies to improve your experience while you navigate through the website. The basic function of these valves is to manage the flow of medium through different piping areas of a system. Let’s start with the basic definition of both ball and plug valves. They have a number of different types based on their structure and function.