Ball valves – find manufacturers and suppliers

Ball valves are used to shut off, open, or divert the flow of liquid or gaseous media in piping systems.

They are among the most commonly used industrial valves and are employed in fields such as mechanical and plant engineering, water technology, chemical and process engineering plants, as well as in the energy, food, and building services sectors.
The central component is a perforated ball mounted in the body between two valve seats. By rotating the ball 90 degrees, the bore of the ball is either aligned with the flow direction or positioned perpendicular to it. This allows the flow of the medium to be quickly opened or shut off with a quarter-turn.
Ball valves are characterized by a compact design, reliable shutoff performance, and low flow losses. A variety of materials, connection types, sealing systems, and actuation methods allow them to be adapted to numerous media and operating conditions.

Below is an overview of the operating principle, designs, applications, advantages, and limitations of ball valves, as well as the most important criteria for selecting them.

How ball valves work

A ball valve essentially consists of a body, a perforated shut-off ball, seat seals, a stem, and an actuator.
When open, the bore of the ball is parallel to the pipeline. The medium can flow through the valve. When the ball is rotated 90 degrees, the closed surface of the ball blocks the flow path and interrupts the flow of the medium.
The ball is connected via a stem to a hand lever, gearbox, or actuator. In manually operated ball valves, the position of the lever usually indicates directly whether the valve is open or closed:

• Lever parallel to the pipeline: open
• Lever perpendicular to the pipeline: closed

Ball valves are primarily shut-off valves. Standard designs are only suitable to a limited extent for the continuous regulation of a flow rate. In a partially open position, high flow velocities, turbulence, and heavy stress on the seat seals can occur. For control applications, therefore, specially shaped control balls or control ball valves designed for this purpose are used.

Types of ball valves

Ball valves are available in numerous designs. They differ, among other things, in the ball’s mounting, the number of flow paths, the bore, the body construction, and the type of actuation.

Ball valves with a floating ball

In this common design, the ball is not rigidly mounted in the body. 
The pressure of the fluid slightly presses the ball against the opposing seat, thereby assisting the seal.
Ball valves with a floating ball are frequently used for small and medium nominal diameters, as well as for numerous general industrial applications.

Trunnion-mounted ball valves

In trunnion-mounted ball valves, the ball is mechanically guided at the top and bottom. 
This allows the ball to be securely positioned even at high pressures and with large nominal diameters.
Sealing is achieved via movable seal seats that are pressed against the ball.
Trunnion-mounted designs are used, among other places, in larger pipelines, in the chemical and petrochemical industries, and in oil and gas supply systems.

Two-way ball valves

Two-way ball valves have one inlet and one outlet. 
They are primarily used to fully open or shut off a fluid flow.
This design is the most commonly used type and is employed in piping systems, machinery, utility systems, and process systems.

Three-way and multi-way ball valves

Three-way ball valves have three connections and are used to distribute, mix, or switch media flows.
Depending on the ball’s bore, two specific types are distinguished:
L-bore: connects two of the three ports and is suitable for switching a fluid flow.
T-bore: allows for different connections between the three ports depending on the valve position and can be used for distributing or mixing.
Multi-way ball valves can simplify more complex piping systems and replace several individual shut-off valves.

Full-bore ball valves

In a full-bore ball valve, the bore of the ball largely corresponds to the inner diameter of the connected pipe.
As a result, the flow of the medium is only slightly restricted.
Pressure loss remains low, and with a suitable design, cleaning or testing equipment can also be passed through the pipeline.

Reduced-bore ball valves

In a reduced-bore ball valve, the ball’s bore is smaller than the inner diameter of the pipe. 
This design is more compact and often more cost-effective, but it creates greater flow resistance.
Whether a full or reduced bore is required depends on the allowable pressure differential, the required flow rate, and the properties of the medium.

One-piece, two-piece, and three-piece ball valves

One-piece bodies are compact and cost-effective, but often allow for only limited maintenance.
Two-piece ball valves consist of a main body and a connected body section.
They are used for numerous standard industrial applications.
Three-piece ball valves have a removable center section. This allows the ball and seals to be serviced or replaced without having to completely disassemble the pipe connections.

Metal ball valves

Metal ball valves are made, for example, of brass, steel, stainless steel, or special alloys.
Brass models are frequently used in building services, water systems, compressed air systems, and general utility systems.
Depending on the design, steel and stainless steel ball valves are suitable for higher pressures, temperatures, and more demanding industrial media.

Plastic ball valves

Plastic ball valves are made from materials such as PVC-U, PVC-C, polypropylene, or PVDF. 
They are lightweight and can offer good corrosion resistance against many chemical media.
However, their suitability depends on the type of plastic used, the medium temperature, the operating pressure, and the chemical composition of the medium.
Plastic ball valves are available in both two-way and three-way configurations.

Soft-seated and metal-seated ball valves

Soft-seated ball valves use seat seals made of plastics such as PTFE.
Under suitable operating conditions, they provide a high level of tightness and low operating torques.
Metal-seated ball valves are used for higher temperatures, abrasive media, or particularly demanding applications.
However, they may require higher operating forces and have different leakage characteristics than soft-seal versions.

Manually, pneumatically, and electrically operated ball valves

Manually operated ball valves are actuated by a hand lever or gear mechanism. 
They are suitable for applications where the valve is operated only occasionally and is easily accessible.
Pneumatic actuators enable fast switching and can be easily integrated into automated systems.
Depending on the actuator design, the ball valve can assume a predetermined safety position in the event of a compressed air failure.
Electric actuators are used when compressed air is not available or when electric control is desired.
Additional position feedback, limit switches, and positioning devices enable integration into control and monitoring systems.

Applications of ball valves

Mechanical and plant engineering

In machine and plant engineering, ball valves shut off cooling, lubrication, water, compressed air, and supply lines. 
Their compact design and short travel distance facilitate integration into machines and systems.

Water and wastewater technology

Ball valves are used in water treatment plants, dosing systems, distribution lines, and various auxiliary circuits.
For drinking water applications, materials, seals, and certifications must comply with the applicable requirements.

Chemical and process engineering industries

In chemical and process engineering plants, ball valves are used to shut off and distribute liquids and gases.
For corrosive media, stainless steel, high-alloy materials, or chemical-resistant plastics may be required.
The sealing materials must also be resistant to the medium and the temperature.

Oil and gas industry

In the oil and gas industry, ball valves are used in process plants, storage facilities, and transport and distribution pipelines, among other applications.
Large nominal diameters, high pressures, and increased safety requirements may necessitate trunnion-mounted balls, special sealing systems, and application-specific testing.

Food and pharmaceutical industry

In hygienic production areas, ball valves are used in product, cleaning, and supply lines.
Here, designs that are easy to clean, suitable surfaces, food-grade materials, and minimal dead spaces are particularly important.

Energy and building services engineering

In heating, cooling, air conditioning, and supply systems, ball valves are used to shut off water, heat transfer fluids, and other suitable media.

Compressed air and gas technology

Ball valves enable the rapid shutoff of compressed air and suitable technical gases. 
For flammable, toxic, or ultra-pure gases, special designs and sealing requirements must be taken into account.

Advantages of ball valves

• Quick opening and closing: A 90-degree turn is sufficient to fully open or shut off the flow of the medium.
• Low flow losses: Full-bore designs, in particular, have low flow resistance when fully open.
• Good shutoff performance: Suitable ball and seat seals ensure a reliable seal against the flow of the medium.
• Compact design: Compared to many lift-type valves, ball valves require very little installation space.
• Simple position indication: For manually operated models, the valve position can often be determined directly by the lever position.
• Versatile material selection: Metallic and non-metallic materials allow for use with a wide range of liquids and gases.
• Easy automation: Ball valves can be equipped with pneumatic or electric rotary actuators.
• Low maintenance requirements: When properly selected and used as intended, many ball valves operate reliably for a long time.

Limitations of ball valves

• Standard ball valves are primarily designed for full opening and closing. Continuous throttling in a partially open position can put stress on the seals and the ball surface.
• Solids, fibers, or abrasive particles can accumulate between the ball and the seat or lead to increased wear. For such media, suitable designs, materials, and sealing systems must be selected.
• When the valve is closed, medium can become trapped in the body cavity between the seat seals. If this medium heats up, the pressure may rise. In such applications, pressure-relieving seat designs or other protective measures are required.
• Ball valves with soft seat seals are limited by the temperature and pressure limits of the sealing materials used. Metal-seated versions expand the range of applications but may result in higher costs and greater operating torques.

Key purchasing criteria for ball valves

Fluid and operating conditions

The selection process begins with a precise description of the medium. Particular consideration must be given to the medium’s chemical composition, concentration, temperature, and viscosity, as well as its solids or particle content, corrosiveness, flammability, and hazard potential.
The body, ball, stem, seat seals, and other components in contact with the medium must be sufficiently resistant to the medium.

Operating pressure and temperature

The ball valve must be designed for the maximum pressure that may occur and the actual medium temperature.
It should be noted that the permissible pressure rating of many materials and seals decreases as temperature rises. Short-term pressure spikes and temperature fluctuations should also be taken into account.

Nominal diameter and flow area

The nominal diameter and pipe connection must be compatible with the system. Additionally, a decision must be made as to whether a full or reduced bore is required.
Full bore is particularly useful when low pressure drops, high flow rates, or an unobstructed pipe cross-section are required. Reduced bore can provide a more compact and cost-effective solution for less demanding flow requirements.

Body and seal materials

The selection should not be limited to the body material alone. The ball, stem, seal seats, O-rings, and body seals must also be suitable for the application.
PTFE is frequently used as the seat seal material. Depending on the medium, temperature, and load, modified plastics, elastomers, or metallic sealing systems may be required.

Connection type

Ball valves are available with the following connection types, among others:

• internal or external threads,
• flange connection,
• weld ends,
• socket-weld ends,
• solvent-cement or fusion-weld sockets for plastic piping systems,
• clamp or other sanitary connections.

The connection standard, nominal pressure, sealing system, and overall length must match the existing piping.

Number of ways and operating function

For a simple shut-off application, a two-way ball valve is usually sufficient.
For three-way versions, it must be clearly specified before ordering which connections are to be connected in the individual switching positions and whether an L- or T-bore is required.

Actuation and automation

For manual operation, accessibility, required torque, and the possibility of a locking mechanism must be checked.
For automated ball valves, the drive type, supply voltage or control pressure, actuation time, fail-safe position, switching frequency, and environmental conditions must be specified.
A standardized mechanical interface, such as that specified in ISO 5211, facilitates the combination of the valve and the rotary actuator. Various manufacturers offer ball valves with a corresponding actuator interface for pneumatic and electric actuators.

Leakage, tests, and standards

The required leak tightness depends on the medium, the pressure, and the consequences of a potential leak.
DIN EN 1983 specifies requirements for industrial steel ball valves with various connection types. DIN EN 12266-1 covers pressure tests, test procedures, and acceptance criteria for metal valves. Depending on the industry and application, additional standards, approvals, and testing requirements may apply.
For hazardous, flammable, or environmentally sensitive media, for example, special requirements may apply regarding fire safety, explosion protection, emission behavior, or functional safety.

Maintenance and interchangeability

For systems with high downtime costs, three-piece or multi-piece ball valves can be advantageous, as seals and internal components are easier to maintain or replace.
The following should also be checked:

• availability of seal kits,
• interchangeability of the actuator,
• access to the valve,
• required maintenance intervals,
• spare parts supply,
• long-term product availability.

Manufacturer, consultation, and lifecycle costs

A suitable manufacturer or supplier should be able to provide advice on the selection of materials, seals, pressure rating, bore size, connection type, and actuator.
In addition to the purchase price, installation, automation, the actuator’s energy consumption, maintenance, spare parts, and potential downtime costs should be taken into account.
A ball valve that is technically well-designed can be more cost-effective in the long run than a low-cost model that must be replaced frequently due to unsuitable materials, excessive operating torques, or premature seal wear.

Summary

Ball valves are compact and versatile industrial valves used to shut off, open, and divert liquid or gaseous media. A perforated ball is rotated 90 degrees, enabling a quick and clearly recognizable switching motion.
Different body designs, ball bearings, passageways, materials, and sealing systems enable their use in numerous industrial and technical applications. For automated processes, pneumatic and electric actuators, as well as various feedback and control options, are available.
To ensure reliable operation, ball valves must be carefully selected based on the medium, pressure, temperature, flow rate, connection type, and switching frequency. Special attention is required for aggressive, abrasive, hot, or hazardous media, as well as for applications with high sealing and safety requirements.

Ball valves can be purchased from various manufacturers and suppliers. Comprehensive information about manufacturers and suppliers of ball valves from around the world can be found on Exportpages.