Q: What is the ball design of the Ball Valve?
A: The most common design is the "floating ball design". The ball is suspended in the media and held in place by two sealing rings. Some high-quality valves have a trunnion ball design. The ball is supported at the top and bottom to reduce the load on the valve seats.
Floating: The majority of ball valves have a floating ball. The ball is supported by the valve seats.
Trunnion: Valves with large diameters and high operating pressures (for example DN >100mm and 30 bar) have often a trunnion design. The ball is supported on the bottom and top to reduce the load on the seat rings. The operating torque is generally lower for trunnion valves.
The hole through the ball may have different profiles such as a full bore, reduced bore or V-shaped.
Reduced bore: Most ball valves have a reduced bore. As a result, the valve introduces friction losses in the system. These losses are still relatively small compared to other types of valves. One-piece ball valves are almost always reduced bore.
Full bore: Full bore valves have the same bore diameter as the pipe. The advantage is that there are no extra friction losses, and that the system is mechanically easier to clean (pigging). The downside is that the ball and the housing are bigger than a standard reduced bore quarter-turn valve. The cost is therefore slightly higher, and for many applications this is not required. They are also called full port ball valves.
V-shaped: The hole in the ball or the valve seat has a 'V' shaped profile. As a result, the desired flow rate can be controlled more precisely by rotating the ball. By optimizing the profile, a linear flow characteristic can be approached.
Q: What material is the shell of a Ball Valve generally made of?
A: The most common housing materials are brass, stainless steel and PVC (PolyVinyl Chloride). The ball is usually made of chrome plated steel, chrome plated brass, stainless steel or PVC. The seats are often made of Teflon, but could also be made of other synthetic materials or metals.
Brass ball valve
Brass has the largest market share. Brass is an alloy of copper and zinc and has good mechanical properties. Brass valves are used for (drinking) water, gas, oil, air and many other media. Chloride solutions (e.g. seawater) or demineralized water may cause dezincification. Dezincification is a form of corrosion where which zinc is removed from the alloy. This creates a porous structure with a greatly decreased mechanical strength. A brass housing is ideal for an air ball valve. View our manual 2-way brass ball valves or 3-way brass ball valves.
Stainless Steel ball valve
Stainless steel is used for corrosive media and aggressive environments. They are therefore often used in seawater, swimming pools, osmosis installations, with high temperatures, and many chemicals. Most stainless steel is austenitic. Type 304 and 316 are the most common, 316 has the best corrosion resistance. 304 is sometimes referred to as 18/8 because of 18% chromium and 8% nickel. 316 has 18% chromium and 10% nickel (18/10). Stainless steel valves usually require a higher operating torque than for example brass or PVC valves. This must be taken into account when a stainless steel valve is operated by an electric or pneumatic actuator. View our manual 2-way stainless steel ball valves or 3-way stainless steel ball valves.
PVC ball valve
PVC often has a lower price (except for ISO-top valves) and are widely used in irrigation, water supply and drainage or corrosive media. PVC stands for polyvinyl chloride. PVC is resistant to the most of the salt solutions, acids, bases, and organic solvents. PVC not suitable for temperatures higher than 60 °C, and is also not resistant to aromatic and chlorinated hydrocarbons. PVC is not as strong as brass or stainless steel, therefore PVC ball valves have lower pressure rating. A more in-depth article about PVC ball valves can be read here.
Q: What types of ball valves can be divided into based on shell assembly?
A: One-Piece Ball Valve
A one-piece ball valve has a single-piece cast body that houses the internal components of the ball valve. This eliminates the risk of leakage of the fluid from the valve. One-piece ball valves are the cheapest ball valves and always have a reduced bore. A welded one-piece ball valve is more common but cannot be dismantled for cleaning and repaired once damaged; therefore, it is only used for applications with a low possibility of particle build-up, and where sanitation is not a major concern. On the other hand, screwed one-piece ball valves can be cleaned, serviced, and repaired, but dismantling requires special tools.
Split Body Ball Valves
Split Body Ball Valves are valves that are assembled on the sides of their balls. A split body ball valve may be a two-piece or a three-piece ball valve:
Two-Piece Ball Valve
A two-piece ball valve consists of housing divided into two pieces that are fitted together. The main piece contains the ball and a connection to one end, and the other piece holds the internal components together and has a connection to the other end. Two-piece housing is the most common type among ball valves. The two parts can be dismantled for cleaning, maintenance, and inspection but it requires removal of the valve from the pipe.
Three-Piece Ball Valve
A three-piece ball valve consists of the housing for the internal components of the valve which are fitted and held together by bolt connections to its two ends. The ends are threaded or welded to the main pipe.
Three-piece ball valves are used for applications that rely heavily on valves, that their maintenance activities must frequently be done. They can be cleaned and serviced easily and their seats and seals can be routinely replaced by just taking the valve body out without disturbing the two ends. Three-piece ball valves are commonly used in the food and beverage and pharmaceutical industries where sanitation is crucial to safety and product quality.
Top Entry Ball Valve
A top entry ball valve allows access to the internals of the valve by simply removing the bonnet on top of the valve. This allows in-line maintenance activities (i.e., dismantling, cleaning, inspection, and repairing the valve) without removing the ball valve from the main pipe.
Q: What types of ball valves can be divided into based on spherical design?
A: Floating Ball Valves
The floating ball is the most common ball design in ball valves. The ball is suspended inside the valve and free to move in a lateral direction when the valve is in a closed position. It is sandwiched between two seats that support the valve and hold it in place. The ball is connected to the shaft in a slot on one end while the other end is free. When the valve is in an open position, the shaft connection to the slot at the top of the ball prevents the ball from moving laterally.
The sealing action is only dependent on fluid pressure. During an operation of a floating ball valve, the inlet pressure of the fluid forces the ball to the outlet seat which prevents the fluid from escaping from the valve body. The fluid pressure on the ball and the seats are higher when the ball valve is in the closed position.
Floating ball valves have the simplest design. They come in smaller diameters and are suitable for liquids and gases operating under low to moderate pressures. The application of floating ball valves is limited by the amount of pressure the seats can handle. At high fluid pressure, the seats can be deformed from the pressure exerted by the ball which can affect the sealing characteristics of the valve under low pressure. Furthermore, the torque to rotate the shaft depends on the force required to counteract the same fluid force acting on the ball and seals.
Trunnion Ball Valves
In a trunnion ball valve, the ball is supported by an additional shaft at its bottom which is called the trunnion. This holds the ball in its place and limits the movement of the ball to its axis. The ball can only move if the valve shaft rotates. Trunnion ball valves also feature spring-loaded seats. The inlet fluid pressure activates the springs towards the ball held by the trunnion, which creates a tight sealing.
Trunnion ball valves are available in small to large diameters, but it is more expensive than floating ball designs. They can operate efficiently in a wide range of pressures and they are ideal for high-pressure applications since the fluid pressure is also dissipated to the trunnion and the springs of the seats. Hence, they are easier to operate with a lower operating torque or a small actuator.
Vented Ball Valve
A vented ball valve is constructed and operates in the same way as a standard ball valve, except that the vented ball has small orifices drilled into its side. When the valve is closed, the orifice is directed to the outlet side of the valve. The drilled hole is used to vent trapped gases which causes a build-up of internal pressure inside the valve, to prevent leaking, valve failure, and explosion.
Vented ball valves are used in compressed air systems, cryogenic processing and conveying volatile liquids are also referred to as the “cryogenic valve” because of their usefulness in cryogenic processing.
Q: What are the advantages of using Ball Valve?
A: Quick and Easy Operation: Ball valves have a simple design, typically consisting of a handle or lever and a spherical ball with a hole through it. This design allows for quick and easy operation, making them ideal for applications where rapid shut-off or control is required.
Reliable Shut-Off: Ball valves provide a reliable and tight shut-off when fully closed. The spherical ball with a hole aligns perfectly with the flow path when closed, minimizing the chances of leakage.
Minimal Pressure Drop: Ball valves typically have a low pressure drop across the valve when fully open. This ensures that the flow of fluid or gas through the valve is not significantly restricted, which is important in high-flow applications.
Durability: Ball valves are generally durable and can withstand a wide range of temperatures and pressures. They are often made from materials such as stainless steel, brass, or PVC, which resist corrosion and wear.
Versatility: Ball valves are suitable for a wide range of fluids and gases, including water, oil, gas, steam, and corrosive chemicals. They are commonly used in industries such as petrochemical, water treatment, HVAC, and pharmaceuticals.
Low Maintenance: Ball valves require minimal maintenance because of their simple design. With proper installation and operation, they can last for a long time without needing frequent repairs or replacement.
Bi-Directional Flow: Ball valves are typically designed for bi-directional flow, meaning they can be used for both forward and reverse flow applications.
Precision Control: Some ball valves are designed for precise flow control by using a V-port or characterized ball. These specialized ball valves are used in applications where accurate control of flow rates is critical.
Reduced Friction: Ball valves have low friction compared to other types of valves, such as globe valves. This can result in less wear and energy savings in some applications.
Fire-Safe Design: Certain ball valve designs incorporate fire-safe features, making them suitable for use in fire protection systems and other critical applications.
Q: How Does a Ball Valve Work?
A: Ball valves can have multiple ports, which are the openings in the valve. Two-way ball valves have two ports and are used for traditional on/off control. Multi-port valves (3-way, 4-way, etc.) are used in applications that require more than one source of media or that need to divert media in different directions.
The port of a ball valve can be opened or closed to control media either manually or through actuation. The manual option requires handles or levers and an operator to control the valve. Electric, hydraulic and pneumatic actuation don’t require an operator to control the valve. Actuation is ideal for complex control systems or those that are in remote areas that an operator cannot easily access.
Q: What parts are there for the Ball Valve?
A: Valve Body
This is the main part of the valve and contains all of the components for on/off control.
Rotary Ball
The ball is designed with a center bore (hole) that the media flows through. The direction of the ball is controlled by turning the stem.
Stem
This connects the ball to the external control mechanism. For example, in a manual ball valve the stem is connected to a handle or lever.
Seats
These are discs that lie in between the body and the ball. Seats provide a seal between the two and also support the ball.
Power Source
The stem of the ball valve is rotated using manual or actuated power sources. Manual actuation includes levers and handles that are controlled by an operator. Automated power sources like electric, pneumatic and hydraulic actuation are also available.
Packing
This is a seal around the stem that prevents the media from escaping.
Bonnet
The bonnet is the part of the body that contains the stem and packing.
Q: What are the designs of Ball Valve holes?
A: Full Bore
A full bore design is also called a full port design. The bore diameter is the same diameter as the pipe, which reduces friction losses and makes the valve easier to clean.
Reduce Bore
A reduced bore design is what you will find in most ball valves. This design has a smaller diameter than a full bore and may introduce small losses of friction.
V-Shaped
The hole in the ball or the valve seat can also have a V-shaped design. V-shaped bores can more precisely control flow rate when rotating the ball.
Vented
A vented ball valve has a small hole drilled into the upstream side. This hole eliminates unwanted pressure within the valve.
Q: What driver types are available for Ball Valve?
A: Ball valves are powered manually or through automated energy sources.
Manual Ball Valves
These are designed with handles or levers that must be controlled by an operator. This option is not intended for high-cycle applications.
Pneumatic Actuation
Pneumatic ball valves require compressed air as a power source. This option is best for applications that require high durability and fast cycling times.
Electric Actuation
Applications without access to compressed air rely on electric actuators, which are also known as motorized ball valves. This option is best for low cycle speeds.
Hydraulic Actuation
Hydraulic actuators are similar to pneumatic, but use pressurized fluid (water or oil) instead of air. This option provides more torque output than others.
Q: How is the Ball Valve installed?
A: Check the material of the entire valve, the body, seat, and the ball to make sure there are no possible defects that could have been caused by storage or in the process of shipping.
Check the valve’s pressure rating in comparison with the ball valve application requirement
Make sure the ball valve’s flange (ANSI 150, NPT, socket weld ANSI), thread (NPT, BSP, socket weld ANSI), and the solvent weld (BLP schedule 40) meet the application requirements.
Clean the flange’s surface, so it is free from debris when it comes in contact with the ball valve.
The valve must be supported where necessary so that the load on the piping is reduced, especially when working with bigger valves.
Install a pipe union. This will allow the valve to be removable for maintenance; it is indispensable when working with metal pipework for two and 3-way valves (BVS, BVF8 & BLS3)
Now ensure that bolts are well tightened on a flange valve one after another. Apply pressure to form a seal between the flanges and valve.
Once that is complete, put the valve to work severally to make sure there are no impingements. If this is done, the device is now ready for operation.
Q: How is Ball Valve maintained?
A: Proper ball valve maintenance culture will help increase their lifespan. To maintain:
The valve should be cycled once every month if it is not active.
Clean the valve using a towel to wipe off dirt, oil, or dust regularly. Do not use cleaning agents that will react negatively with the valve’s material.
Lubricate regularly using water-insoluble, synthetic, or oil-based lubricants.
A routine inspection should be carried out at intervals by a trained inspection officer.
Q: What to consider before buying ball valves?
A: Before purchasing ball valves, several factors need to be put into consideration so as to get the perfect value for money. Some of the things that should be considered before buying ball valves include:
Material
Nobody wants to buy a product made with the wrong material, unsuitable for their case application, or even counterfeit materials. Ball valves are made with different materials, some of which are:
PVC: Polyvinyl Chloride (PVC) is a type of plastic used especially in making industrial water valves. It is a durable, rugged, and rigid material. One main advantage of PVC ball valves is that they are less expensive than most other materials. PVC valves are corrosion resistant.
Stainless Steel: it contains chromium in high quantity and some nickel too. Stainless steel is used in making different ball valve types be because of the many essential attributes it contains. It is famous for its durability and high corrosion resistance.
Iron: This material is the most commonly used in oil and gas, water, and steam lines. This is because iron is capable of resisting a wide range of pressure and temperature
CPVC: CPVC or chlorinated PVC contains almost all the features of PVC; the difference is that CPVC can withstand higher temperatures. It is suitable for ball valves that handle hot water.
Bronze and Brass: this material is water and corrosion-resistant. It is popular because of its shiny surface, high durability, and toughness. Bronze and Brass ball valves are an ideal ball valve for high temperature applications.
PP: Propylene monomer is also used for making Polypropylene Ball Valve (PP). It has the ability to resist acids and bases. This material is durable, flexible, lightweight, and rigid thermoplastic. Polypropylene Ball Valves are commonly used in the consumables industries like sugar, flour, etc., and other products like chemicals, fertilizers, and paper, among numerous lots.
Design
Ball valves come in different designs, as will be required by the specific purposes they were designed for. The user application determines the design that should be bought.
Popular ball valve designs are:
Full Bore
Reduced Bore
V-shaped
Vented
Ball Valve Standard
Before buying a ball valve, it must be certified standard by the relevant organizations.
ANSI: the American National Standards Institute is an organization saddled with the responsibility of setting voluntary safety standards for manufacturers in the United States. Check for ANSI’s label on ball valves to confirm their safety.
Uniform Plumbing Code (UPC): The Uniform Plumbing Code are set of codes and standards set by the International Association of Plumbing and Mechanical Officials (IAPMO) to ensure the safety of both plumbers and consumers alike. All the best types of plumbing valves have this.
Underwriters Laboratories (UL): this global organization is responsible for testing mechanical parts, which includes ball valves, to ensure that they function correctly. The UL also devotes itself to promoting safe industrial practices in industries of all countries.
Ball Valve Sizes
Ball valves come in numerous varying sizes. Although some ball valves are made custom to fit specifications, there generally are standard sizes that are common in the ball valve market.
The sizes have their specific purpose, which they serve, a size for a function. When buying a ball valve, check for the size suitable for your application so as not to buy the wrong one. Some of the standard sizes you will find on the label are:
2-inch ball valve
1-inch ball valve
¾ ball valve
½ ball valve
⅜ ball valve
¼ ball valve.
Working Pressure
The working pressure, as seen on the label as ratings, indicates the application type a ball valve is most suitable for.
Some of the pressure ratings you will find are:
Pressure Nominal Classes (PN)- the PN Class number tells you the amount of pressure the ball valve is able to withstand. It is displayed on the item as bars, and each bar represents 14.5038 pounds of pressure.
PSI Rating – PSI stands for pounds per square; it is commonly used in the United States as a measurement of pressure for equipment and instruments. PSI rating indicates the pressure of liquid or gas that a ball valve is capable of allowing its flow through the pipe.
WSP Rating: WSP stands for Working steam pressure, which tells buyers the maximum pressure of steam that a ball valve can withstand at the highest temperature rating.
CWP & WOG Ratings: CWP stands for Cold working pressure and WOG for Water, oil, and gas. CWP indicates a ball valve’s maximum pressure rating between the temperatures of -20° Fahrenheit to 100° Fahrenheit. CWP is commonly used with the valve’s pressure rating.
The WOG rating, however, has become old and is no longer used as often as it was before. This rating means that it is suitable for water, oil, and gaseous substances applications.
Q: How Do You Repair a Ball Valve?
A: Ball valves are generally very hard-wearing, and for the most part, they require little maintenance to keep running smoothly for a long time. This is partly to do with the simplicity of their design and operation.
However, over an extended period of service, the components of a ball valve can wear down. When this happens, they may become stiff or loose, or gradually lose their effectiveness in providing a perfect shut-off function. If you suspect that a worn ball valve may be causing issues in a plumbing system, there are some basic steps that you should take to investigate and solve the problem.
The tools that you will need to repair or replace a ball valve will vary, depending on both the type of ball valve in question as well as the damage which needs to be fixed. A spanner or pipe wrench is usually all you will need to check a domestic plumbing ball valve, but you should also keep a cloth to hand to catch any excess liquid as you disassemble the pipe fittings around the valve.
Firstly, shut off the water supply to the affected area or system. You will need to do this both to inspect the ball valve for impaired function and to avoid wasting water or causing further damage to the surrounding area. After draining any excess water from around and within the ball valve and its port, dry the valve with a cloth
Check which type of fitting your valve uses and remove the ball valve from the port accordingly. Once removed, disassemble the ball valve in an organised and logical order. Keep the constituent parts together and note the order in which they were previously assembled. This will make reassembly much easier, minimising the risk of errors and omissions
Carefully inspect each component of the valve, looking particularly for signs of wear and tear. This includes cracks, splits, physical damage, worn patches, or any signs of leaking or excessive stiffness. If the damage is limited to a single component, you may be able to replace just that part rather than the whole unit
If the damage is hard to visually identify or multiple parts are damaged, it may be easier to replace the entire ball valve. This should be a reasonably easy process in most systems, due to the range of fitting options on offer. In addition to compression, push fitting and threaded ball valves, solvent cement socket valves are another common alternative.
Q: Can a Ball Valve Reduce Water Pressure?
A: No, a standard ball valve, when fully open, does not reduce water pressure. It allows water to flow through with minimal resistance, maintaining the pressure of the incoming water. The primary function of a ball valve is to control the on/off flow of fluids, and when fully open, it offers a low pressure drop.
However, it’s important to note that if a ball valve is partially closed, it can create a restriction in the flow. This restriction can potentially reduce the flow rate and, consequently, the pressure downstream of the valve. In such cases, a partially closed ball valve can act as a flow control device and may reduce the water pressure downstream of the valve. However, ball valves are not designed to function this way and it could lead to extra wear and tear or even failure of the valve.
Q: Is a Ball Valve Better Than a Plug Valve?
A: It depends the choice between a ball valve and a plug valve depends on the specific requirements of the application, as both have unique features and advantages. A plug valve, also known as a cock valve, utilizes a tapered or cylindrical plug to control the flow of liquids or gasses through a quarter-turn motion. It is favored for its simplicity, and tight shut-off, and is commonly used in industries like: water treatment, oil & gas, and chemical processing. On the other hand, a ball valve relies on a hollow, pivoting ball to regulate fluid flow with a quarter-turn motion. It offers fast and efficient operation, durability, and a long life span, making it a popular choice in heating and cooling systems, water distribution, and industrial process cooling.
