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Floating Ball Valves

Floating ball valves are offered by all of our principal valve manufacturers, Pekos and Starline. Various configurations and design features are available. Floating ball valves are used in many industrial applications and are available as simple quarter-turn isolation valves and also multiport valve configurations. We can provide advice and recommendations for valve selection depending on the various criteria required.

Pekos Valves

Size Range½” – 16”
Pressure ClassANSI 150#, 2” – 24”
ANSI 300#, 2” – 18”
ANSI 600#, 1” – 8”
MaterialsWCC / LCC / CF8M / Bronze AB2
TrimSt. Steel F316 and Exotic
ConstructionFull Bore bolted, Reduced Bore end entry
DesignFloating Ball, Guided Ball and Full Trunnion Mounted.
Seat InsertsPTFE / RPTFE / TFM
CertificationNACE, PED CE/CA, ATEX, Ta Luft, Lloyds Firesafe & Type Approval
FeaturesLT AED O-Rings, ISO Top flange, Emergency Sealant Injection (300# & 600#), European Origin Materials
Starline Ball Valves logo

Size Range½” – 4”
Pressure ClassANSI 150#
ANSI 300#
ANSI 600#
ANSI 800#
MaterialsA105 / LF2 / F316/L / Duplex F51-F5
TrimSt. Steel F316 and Exotic
ConstructionFull Bore & Reduced Bore, Bolted Body Construction
DesignFull Trunnion Mounted, Double Block & Bleed
Seat InsertsVirgin PTFE / RPTFE / Devlon / Peek
CertificationNACE, PED CE/CA, ATEX, Firesafe Certified, API Monogram
FeaturesLT AED O-Rings, ISO Top flange, Emergency Sealant Injection (300# & 600#), European Origin Materials
Starline Ball Valves logo

Size Range½” – 2”
Pressure ClassANSI 150#
ANSI 300#
ANSI 600#
MaterialsA105 / LF2 / F316/L
TrimSt. Steel F316 and Exotic
ConstructionFull Bore & Reduced Bore, Bolted Body Construction
DesignFull Trunnion Mounted, Double Block & Bleed
Seat InsertsPTFE / RPTFE
CertificationNACE, PED CE/CA, ATEX, Firesafe Certified, API Monogram
FeaturesLT AED O-Rings, ISO Top flange, Emergency Sealant Injection (300# & 600#), European Origin Materials
Starline Ball Valves logo

Size Range½” – 6”
Pressure ClassANSI 900#
ANSI 1500#
MaterialsA105 / LF2 / F316/L / Duplex F51-F53-F55
TrimSt. Steel F316 and Exotic
ConstructionFull Bore & Reduced Bore, Bolted Body Construction
DesignFull Trunnion Mounted, Double Block & Bleed
Seat InsertsPTFE / RPTFE / Peek
CertificationNACE, PED CE/CA, ATEX, Firesafe Certified, API Monogram
FeaturesLT AED O-Rings, ISO Top flange, Emergency Sealant Injection (300# & 600#), European Origin Materials
Starline Ball Valves logo

Size Range½” – 2”
Pressure ClassANSI 150#
ANSI 300#
ANSI 600#
MaterialsA105 / LF2 / F316/L
TrimSt. Steel F316 and Exotic
ConstructionFull Bore & Reduced Bore, Bolted Body Construction
DesignFull Trunnion Mounted, Double Block & Bleed
Seat InsertsPTFE / RPTFE
CertificationNACE, PED CE/CA, ATEX, Firesafe Certified, API Monogram
FeaturesLT AED O-Rings, ISO Top flange, Emergency Sealant Injection (300# & 600#), European Origin Materials
Starline Ball Valves logo

Size Range1” – 8”
Pressure ClassANSI 150#
ANSI 300#
ANSI 600#
ANSI 900#
ANSI 1500#
ANSI 2500#
MaterialsA105 / LF2 / F316/L / Duplex F51
TrimSt. Steel F316 and Exotic
ConstructionFull Bore & Reduced Bore, Bolted Body Construction
DesignFull Trunnion Mounted, Double Block & Bleed
Seat InsertsRPTFE / Devlon / Peek
CertificationNACE, PED CE/CA, ATEX, Firesafe Certified, API Monogram
FeaturesLT AED O-Rings, ISO Top flange, Emergency Sealant Injection (300# & 600#), European Origin Materials

Floating Ball Valve Design

In a floating ball design, the ball moves or floats between the two seats with pressure. The valve is designed to seal against the downstream seat as the ball moves from the upstream side. A slot in the ball enables the ball to move in this way. This type of design is typically used on low pressure valves and also larger sizes depending on the differential pressure and the sealing characteristics required. It is also typical on small high-pressure valves.

Floating ball valves can be manufactured with firesafe capabilities which is normally specified for valves used in Petrochemical and hazardous applications. A metal seat profile is usually incorporated in the body to act as a secondary seat seal in the event of a fire when the soft seat components are destroyed.

Floating ball valves are generally less complex than a Trunnion design with fewer components, it is therefore usually less expensive.

A variation to a standard floating ball design is a guided design used on larger sizes and low pressures with design features to help support the weight of the ball and improve performance.

Cavity Pressure Considerations

In floating ball valves it’s also important to think about issues that can occur with a build-up of cavity pressure. Valve seats can be designed to allow cavity pressure to pass and equalise with the line pressure. However, some quick expanding gases need special consideration, and it is sometimes recommended to provide a supplementary vent hole in the upstream side of the ball ensuring that cavity pressure cannot build up, this means the valve is uni-directional and is supplied with a flow arrow.

When a floating ball valve is in the open position in some circumstances there can also be a pressure build up in the cavity, a vent hole in the stem slot can be included to equalise the cavity pressure with the line pressure ensuring improved operation, the valve is still bi-directional with this feature.

Hard seats such as Peek, Nylon or Metal in floating ball valves can be problematic as they increase the seat torque making the valve difficult to operate. Design variations are available to reduce these issues by including a flexible seal behind the seat such as a graphite ring, O-Ring, or spring.

Frequently Asked Questions

A floating ball valve is a type of quarter-turn valve that uses a floating ball to control the flow of fluid through a pipeline. The ball is held in place by two seats, which creates a seal against the ball when the valve is closed, preventing the fluid from flowing through the pipeline.
Floating ball valves have several advantages, including a low torque requirement for operation, a quick response time, and a compact design. They are also relatively easy to maintain and can be used in a wide range of applications.
There are two main types of floating ball valves: two-piece and three-piece. Two-piece floating ball valves have a two-piece body design, with the ball and stem attached to one half of the body. Three-piece floating ball valves have a three-piece body design, with the ball and stem attached to a separate piece that can be removed for maintenance.
Floating ball valves are typically made from materials such as carbon steel, stainless steel, brass, bronze, and other exotic alloys. The material used depends on the application requirements, such as pressure rating, temperature range, and corrosive properties of the fluid being handled.
Floating ball valves undergo rigorous testing to ensure quality and performance. This includes hydrostatic testing to verify the valve body's strength and pressure resistance, seat and seal testing to verify tightness and leakage prevention, and torque testing to verify the actuator's efficiency and functionality. The valves are also subjected to performance testing to verify the flow rate, operating torque, and other functional parameters.
The selection of the right floating ball valve depends on several factors, such as the pressure rating, temperature range, fluid type, and flow rate of the application. Other factors to consider include the valve size, connection type, and end connections. Consulting with a valve manufacturer or supplier can help ensure that the right valve is selected for the specific application.
The maximum pressure rating for floating ball valves varies depending on the design and construction of the valve, as well as the materials used. Generally, floating ball valves can handle pressures ranging from class #150 to #2500, but some designs may be able to handle even higher pressures.
Yes, floating ball valves can be used for both on/off and throttling applications. However, their design is optimised for on/off applications, and they may not be as effective as globe valves or other specialised valves for precise throttling control.
The lifespan of a floating ball valve depends on several factors, such as the application, frequency of use, and maintenance practices. Generally, floating ball valves are designed to last for many years, with a lifespan of up to 20-30 years or more in some cases.
Yes, floating ball valves can be automated using actuators. This allows for remote operation and control of the valve, as well as integration with control systems for monitoring and automation.
Floating ball valves are commonly used in a variety of industries and applications, including oil and gas, petrochemicals, water treatment, HVAC systems, and more. They are particularly well-suited for applications where low torque and quick response times are needed, and where space and weight constraints are a concern.
Floating ball valves can be constructed from materials that are resistant to abrasion and corrosion, such as stainless steel, bronze, or exotic alloys. Additionally, some floating ball valves can be coated or lined with materials that provide additional protection against abrasive or corrosive fluids.
Maintenance and repair of a floating ball valve involves regular inspection, cleaning, and lubrication of the valve components. Depending on the specific design and construction of the valve, repairs may involve replacing worn or damaged seats, seals, or other components. In some cases, the entire valve may need to be replaced.
Full bore floating ball valves have a ball with a bore that is the same size as the pipeline, allowing for unobstructed flow through the valve. Reduced bore floating ball valves have a ball that is smaller than the pipeline, creating a restriction in the flow path. Full bore valves are typically preferred for applications where maximum flow capacity is required, while reduced bore valves may be used in applications where space and weight constraints are a concern.
In floating ball valves the line pressure pushes the ball onto the opposite seat – the higher the pressure, the better the seal. WrTunnion mounted ball valves use a fixed ball that is supported by trunnions / bearings on the centre line of the valve seats and the seats “float” onto the ball. Trunnion mounted ball valves are typically used in higher pressure and larger diameter pipelines, while floating ball valves are better suited for smaller diameter and lower pressure applications. Trunnion mounted ball valves are generally more expensive and have a more complex design than floating ball valves.
One-piece, two-piece, and three-piece floating ball valves refer to the number of components that make up the valve body. One-piece valves have a single body that is cast or machined as a single piece, while two-piece valves have two separate pieces that are threaded or bolted together. Three-piece valves have three separate pieces that can be disassembled for maintenance or repair. Generally, one-piece valves are more compact and lighter weight, while three-piece valves are easier to disassemble and maintain.
The seat in a floating ball valve provides a seal around the ball to prevent fluid from leaking past the valve. The seat is typically made of a soft material, such as Teflon or rubber, that conforms to the shape of the ball and provides a tight seal.
Soft-seated floating ball valves use a seat made of a soft material, such as PTFE, that provides a tight seal against the ball. Metal-seated floating ball valves use a seat made of a hard material, such as stainless steel coated with a hard material such as tungsten carbide, that is resistant to wear and erosion. Metal-seated valves are typically used in applications where the fluid is abrasive or corrosive, while soft-seated valves are used in applications where a tight seal is more important than resistance to wear.
Manual floating ball valves are operated by hand using a lever or handle, while automated floating ball valves are operated using an actuator. Actuators can be pneumatic, electric, or hydraulic, and can be used to open and close the valve remotely, or to control the valve position based on signals from a control system.

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