Floating Ball Valve

A: Floating ball valves are operated by a shaft, or stem, attached to the top of the ball that turns it 90 degrees (a quarter turn). As the ball rotates, the port is covered or uncovered by the wall of the valve body, either releasing or halting the flow of media. The stem is attached loosely enough to the ball that, as the ball rotates on its axis, the pressure of the flow pushes the ball against its downstream seat, creating a tight seal. For this reason, floating ball valves may not seal as effectively in very low pressure applications after a certain amount of seat wear has occurred. This is because there may not be enough media pressure to force the ball against the downstream seat to create a tight seal. However, in most applications downstream pressure is sufficient to maintain a tight seal long after the seats have begun to wear.

A: Though floating ball valves have numerous applications, their purpose is essentially just to control how liquids flow through pipelines, though these aren’t the only type of ball valve used for this purpose. The other major type – a trunnion ball valve – is also used for such purposes, and a bit later we’ll compare it to the floating variety.
A floating ball valve gets its name from the hollow, ball-like sphere that “floats” freely inside the valve’s body, which is compressed between two flexible seats while suspended in liquid. What a floating ball valve normally does during operation is float slightly downstream, which causes the seating mechanism to compress under the ball. Should the seating disintegrate, the ball floats to the metal stem to seal it. This provides a failsafe within the design.
The system also involves a stem in the valve’s body that connects it to a slot at the top of the ball and allows the ball to rotate 90 degrees. This stem allows the ball to move laterally when upstream pressure acts on it, while the other downstream seat improves the tightness of the valve’s seal. This allows the valve to close when liquid flows in either direction.
The ball itself has a hole through which liquids pass freely when it’s correctly aligned with both ends of the valve. This hole, when perpendicular, seals the valve. When this hole is in any other position, liquid will continue to flow through it. The floating ball valve can stop, distribute and alter the direction liquids flow within a pipeline, with its main features being the sealing design of the seats, which automatically relieve pressure, reliably sealing when flows reverse and acting as a locking device.
Pressure acts on the closed valve on the backside of the upstream seat as well as the ball, which forces the ball in the direction of the downstream seat. This force both deforms and limits the valve seats. This temporary deformation is engineered into the seats’ design, using stored energy to temporarily change its shape in order to keep the seal when temperatures or pressure changes.

A: The main difference between a floating and a trunnion metal seated ball valve is that trunnion ball valves have shafts to hold the ball in place.
First, it’s important to understand the differences between floating and trunnion ball valves. Essentially, these are two different ways the valve supports the internal ball.
In a floating ball valve, the seats hold the ball in place and it floats around in the valve body. Upstream pressure from liquid or gas pushes the ball up against the downstream seat. This helps form a leak tight seal.
By contrast a trunnion metal seated ball valve uses shafts on the top and bottom of the ball to hold it in place. As such, the ball stays in place and does not move laterally inside the valve body. Instead, to provide a tight seal, floating seats surround the ball and are always in contact with it. With pressure, the seats press against the ball to form a seal.
Generally speaking, a floating ball valve will require more torque to operate than a trunnion ball valve. Also, floating ball valves are typically limited to smaller valves compared to trunnion options.

A: A floating ball valve is a simple valve that has a good sealing performance.
The load from the sphere is transmitted to the outlet sealing ring.
The sealing ring should be made of a material that can bear the working load of the sphere medium.
This type of valve is typically used for low and medium-pressure applications.
In a floating ball valve, the ball floats inside the valve. It is not connected to anything. The valve seat is fixed, and the ball is free.
When the pressure changes, the ball moves towards the opening and creates a tight seal to stop the flow.
In this type of valve, the ball is pushed towards the opening to control the flow.
Floating ball valves are often used in multi-port applications.
They are ideal for high-pressure and low-pressure applications, as well as for suspensions containing tiny solid particles.
Firstly, they boast a lower risk of leakage in comparison to trunnion ball valves, rendering them apt for applications where leak prevention is paramount.
Their maintenance is notably more straightforward than trunnion ball valves, which can be intricate to repair, often necessitating system-wide halts for maintenance procedures.
Cost-effectiveness is another feather in their cap, as floating ball valves generally come at a more affordable price point than their trunnion counterparts.
Their versatility shines through in their compatibility with various fluids, easy operability, and suitability for applications in confined spaces.
Offering a rapid response to shutting off or allowing fluid flow, floating ball valves prove invaluable for emergency shut-off systems and critical applications.
The design featuring a floating ball ensures impermeable sealing when pressed onto its seats, guaranteeing a tight seal and preventing any media from leaking through the valve.

A: Spherical Element
Both valve types employ a spherical element, commonly referred to as a ball, to regulate the flow of fluids.
Low Flow Resistance
A notable commonality is the minimal flow resistance exhibited by both valve types, rendering them well-suited for applications prioritizing low resistance to fluid flow.
Versatility with Fluids
Both valves demonstrate versatility, being suitable for use with a diverse range of fluids, making them adaptable to various operational scenarios, including confined spaces.
Quarter-Turn Actuation
Another shared characteristic is the quarter-turn actuation mechanism, ensuring ease of operation.
This feature makes them particularly suitable for emergency shut-off systems and critical applications where quick response is essential.
Valve Stem Control
Both valve types incorporate a valve stem to control the movement of the ball, contributing to their operational efficiency and control.

A: A floating ball valve comprises 3 main parts:
An actuator lever.
A stem.
A floating ball.
The actuator lever is the outermost part used to open or shut-off fluid flow. When it is turned within a 90-degree angle, it rotates the stem which turns the ball to an open or closed position.
At the base of the valve, the ball remains unmounted and is only supported by a stationary polymer ring and seats.
When the valve is shut, medium pressure pushes the ball firmly against the seats. This provides a tight seal and stops flow immediately. However, given as the ball is unsupported, high levels of pressure can not be distributed to a base to lessen the force on the ball. A floating ball valve is thus only recommended for low to medium pressure applications with average temperatures. Where necessary, it can also be customized to work in cryogenic applications.
Regarding overflow management and controlling leakages, a quality floating ball valve should have an anti-static and anti-blow out stem design. This means that in instances when pressure is elevated or during fluid surges, the stem would remain in place with no leakages. A flexible soft seat is equally essential as it creates sealing around the floating ball to stop media flow.

A: The efficiency of floating ball valves makes them ideal for applications such as:
Emergency shut-off systems- pipeline systems such as those involving fuels, water, or critical gases often require a fast-responding shut-off valve in case of emergencies. Given as this type of ball valve is unmounted, it works fast and is therefore suitable for SIL 3 emergency shut-offs.
Water systems- water distribution systems require that pressure is maintained at optimum levels to sustain flow and prevent air pockets from restricting the flow of water. The flow of water also needs to be controlled to prevent overflows. A floating ball valve would be a good choice for water system control as it is pressure-sensitive and can open and shut as needed based on pressure conditions.
Pipeline pressure relief– pipeline pressure management is essential to avoid busts and similar mishaps. A floating ball valve can be added in a pipeline as a pressure outlet valve as it takes on the pressure while remaining intact as opposed to a mounted ball valve that could sometimes blow out.

A: Composite seal
A valve seat is provided on both the upstream and downstream sides of the valve, and the valve seat is embedded in the valve body by means of a special press.
It relies on the elasticity of the valve seat to provide the initial preload.
The seats at upstream and downstream sides of the valve are completely symmetrical, and there is no restriction on the installation direction. It is a two-way valve.
It is mainly used for applications with working conditions below 150℃ (special material can reach 250℃)
It has the advantages of flexible operation and reliable sealing.
Commonly used soft sealing materials include: PTFE, RPTFE, NYLON, PPL, PEEK, etc.
Metal hard seal
The upstream side of the valve is provided with a seat assembly, and the sealing surface is covered with a carbide. The downstream side of the valve body is directly welded.
The seat at the upstream side of the valve provides the necessary initial sealing specific pressure for the valve, the seat at the downstream side of the valve plays the main sealing role, and the valve has a restricted installation direction.
These seals are mainly used in applications with working conditions that include high temperature, and the presence of particles, dust, slurry, etc.
It has the advantages of being high temperature, high pressure, wear and erosion resistant, while being a reliable sealing.
The usual surface covering material is Stellite cemented carbide.
Soft seal
Two valve seat components are provided on both the upstream and downstream sides of the valve. Each valve seat component is formed by a valve seat, a valve seat ring, and a gasket ring. The valve seat ring is fixed in the valve seat by the gasket ring, and an O-ring is arranged between the valve seat and the valve body type sealing ring. On the one hand, the valve seat and the valve body are sealed, on the other hand, it can provide the initial pretension of the valve.
The two valve seats are completely symmetrical, the valve has no restrictions on the installation direction, and it is a two-way valve.
The metal seal is the primary seal, which is used to cut off most of the medium and block the particulate impurities in the medium from entering the soft sealing surface. The soft seal is the secondary seal, which is used to completely block the medium.
These seals are mainly used in applications where the working conditions include the presence of particles, dust, slurry and other media under normal temperature (below 150℃)
It has the advantages of having flexible operation, wear and erosion resistance, long service life and being a reliable sealing type.
The material used for soft seals (valve seat ring) is usually a type of rubber.

A: The main pipeline for oil and natural gas transportation needs to be a clean pipeline, and it needs to be buried underground. For buried pipelines, it is recommended to select full-diameter welded or flanged ball valves. For branch pipes, it is recommended to select flange connections or welded connections with a full diameter or a reduced diameter ball valve.
For the pipeline and storage equipment of oil products, it is recommended to use flanged ball valves.
For city gas and natural gas pipelines, the choice of suggested is floating ball valves with flange connection and female connections.
The metallurgical oxygen piping system should use rigorously de-aliphatic oxygen valves.
When working with fluids at very low temperatures, it is recommended to select the low temperature ball valve with a valve cover
The pipeline system of the catalytic cracking unit of the oil refining unit can be used with a lifting rod ball valve.
In the equipment and piping systems of corrosive media such as acids and alkali used in the chemical industry, it is appropriate to select stainless-steel ball valves made of austenitic stainless steel with polytetrafluoroethylene as the seat ring.
Metal-to-metal sealed ball valves can be used on the piping systems or devices which work at high-temperature in metallurgical systems, power systems, petrochemical plants, and urban heating systems.
When flow adjustment is required, worm gear drive, pneumatic or electric adjustment ball valve with V-shaped opening can be selected.

A: A floating ball valve uses a rotating ball and a stem that provide on/off flow control. When the valve is positioned where the bore is aligned in the same direction as the pipeline, it is in the open position, and fluid can pass downstream. When the ball is rotated 90-degree, the bore becomes perpendicular to the flow path, meaning the floating ball valve is closed, and fluid cannot pass downstream.
Advantages of a floating ball valve include Fast shut off, only a 90-degree turn required to close the valve. The opened or closed state of the valve can be easily detected by position of the handle.
Floating ball designs feature a ball only attached to the stem, without the use of energized seats. Line pressure causes the ball to move or “float” against the downstream seat, creating a positive seal, not allowing media to pass through. The Floating Ball provides tight seal, even after long periods. It is very compact in design compared to other isolation valves, perfect for use in areas with space restraints.

A: The floating ball valve has a simple structure and good sealing performance. However, the load of the sphere which bears the working medium is all transmitted to the outlet sealing ring. Therefore, it is necessary to consider whether the sealing ring material can withstand the working load of the sphere medium. When it is under higher pressure impact, the sphere may shift. As a result, this structure is generally used for medium and low-pressure ball valves.
The overall characteristics of the ball valve floating type are small size, lightweight, simple structure, and a sphere with a free-floating function to better ensure sealing. The ball valve uses a ball with a circular through the hole as the opening and closing part, which rotates 0-90 degrees around the center of the stem under the drive of the valve stem to complete the opening and closing function. It has the characteristics of compact structure and fast switching. It can turn 90 degrees to close the valve and cut off the pipeline medium. The diameter of the spherical passage is the same as the diameter of the pipeline. The flow resistance is small and the flow capacity is large. The valve stem is downloaded, which prevents the accident of the valve stem penetration and ensures the safety of use.

A: Floating ball valves feature all the basic components of a ball valve. In addition to these components, other add-ons like O-rings and extra packing can also be added to customize the valve. Here is a look at some of the main parts of a floating ball valve.
Body
The body of the floating ball valve houses all the moving parts. It may be a single unit or divided into different pieces. The body is designed to protect the working parts of the valve and make it easier to connect the valve to the pipeline. It is also the first pressure boundary of the valve. Floating ball valve body is usually made of carbon steel, stainless steel, low-temperature carbon steel, duplex, super duplex, inconel, and more.
Trim
The trim houses all the moving parts of a floating ball valve. These parts include the stem, ball, seats, and sleeves of the valve. The stem connects the actuator to the disk or ball. It is connected to a slot at the top of the ball and can move the ball to a quarter turn. Floating ball valves feature anti-blowout stems that can handle both medium and low temperatures. The disk in a floating ball valve is in the shape of a hollow ball. The hollow center of the ball is known as the bore. The ball is made of steel and has perforations on it for better sealing. It is connected to the stem on one end and has the ability to freely float in the valve. Floating ball valves feature two elastomeric seats. The seats have seal rings that provide tight shut-off when the valve is turned off and protect the seats against high-pressure when the valve is turned on.
Actuator
The actuator is what you use to open and close the valve. It is connected to the stem on one end so that when you move the actuator, the stem moves as well. Many kinds of actuators can be used with floating ball valves depending on the application and the medium. Some common types include bare stem, gear, hand lever, pneumatic actuator, hydraulic actuator, gas actuator, gas-over-oil actuator, motor-operated actuator, hydraulic/ electro actuator, hydraulic-operated actuator, and more.

A: Floating ball valves have many different sizes, types, and configurations. They are very versatile and can be customized to suit any kind of application or pipeline such as carbon steel ball valve. Here are some common types of floating ball valves.
Based on Bore Size
The hollow center of the ball is called the bore. There are two types of floating ball valves based on bore size.
Full Bore Floating Ball Valves
Full bore floating ball valves feature a bore size that matches the diameter of the pipeline the valve is connected to. These valves allow the flow of medium without any restrictions and are suitable for liquid and gaseous mediums. In full bore floating valves, the onstream pressure from the pipeline affects the entire surface area of the ball, pushing it against the downstream seat more effectively. Full bore floating ball valves provide tighter seals than any other kind of ball valve.
Reduced Bore Floating Ball Valves
In reduced bore floating ball valves, the size of the bore is a few nominal sizes less than the diameter of the pipeline. These valves are suited for applications where the flow of medium needs to be restricted. They are mostly used in the oil and gas industry. In reduced bore floating valves, the onstream pressure from the pipeline affects a dedicated portion of the ball. This means a certain level of pressure is required to push the ball against the downstream seat. Reduced bore floating ball valves can only be used in applications where the pressure is high enough to achieve tight shut-off of the valve.
Based on Assembly
Floating ball valves can have one, two, or three pieces joined together through welded or forged connections. There are three types of floating ball valves based on assembly.
One-Piece Floating Ball Valve
This type of floating ball valve features a single cast or forged steel body that houses all the moving parts of the valve. Single-piece floating ball valves are available in different sizes and are the most compact type of ball valve. They are the cheapest floating ball valves available in the market and are widely used in smaller applications. Single-piece floating ball valves cannot be opened for cleaning, repair, or maintenance so they are mostly used with mediums like gasses where little maintenance is required.
Two-Piece Floating Ball Valve
Two-piece floating ball valves feature two pieces of housing that are either forged or cast together. One piece of the valve is always larger than the other and it houses all the moving parts of the valve. Two-piece floating ball valves can be opened for maintenance, repair, and cleaning. However, the valve needs to be disconnected from the pipeline to do so.
Three-Piece Floating Ball Valve
This type of floating ball valve features three pieces of housing or body. These valves are larger in size and more expensive. You can also find small-sized three-piece floating ball valves for compact applications. The three pieces of the body are forged to each other. One half of the body is bigger and houses all the moving parts of the valve. This type of valve can be easily maintained, repaired, or cleaned without having to remove the valve from the pipeline.

A: Body:
The valve body is the main structure of this valve. It holds the ball, stems, and other internal components. The body is designed to withstand high pressure and temperature. The body of the floating ball valve is made from various materials such as carbon steel, stainless steel, and cast iron.
Seats:
The valve seats are located on both sides of the ball. Its purpose is to provide a seal against the ball. The seats are made from a material such as PTFE or reinforced graphite. This material prevents damage to the ball and provides a tight seal.
Ball:
The ball is a spherical or cylindrical-shaped part of the floating ball valve. It controls the flow of fluid through the valve. The ball is usually made from a rigid material, such as stainless steel, brass, or chrome-plated steel. However, it is designed to fit tightly against the valve seats to prevent leakage.
Stem:
The stem is an extended, slender component that connects the ball to the handle or actuator. The stem is made from stainless steel or a similar material. It is designed to withstand the forces generated during operation.
Handle or Actuator:
The handle or actuator is used to control the opening and closing of the valve. The handle is manually operated, while the actuator can be electric or pneumatic, depending on the application.

A: Lower Cost
Floating ball valves are generally less expensive than trunnion ball valves, making them more cost-effective for low-pressure applications.
Easy Maintenance
Floating ball valves are easier to maintain than trunnion ball valves. The ball and stem can be easily removed from the valve body for inspection and repair.
Quick Operation
Floating ball valves are designed for quick and easy operation, making them suitable for fast-operation applications.
Better Flow Control
Floating ball valves offer better flow control than trunnion ball valves due to the full-port design, which reduces turbulence and pressure drop.