In today’s discussion, we will explore the key differences between two commonly used types of ball valves: the floating ball valve and the trunnion mounted ball valve. These two valve designs play crucial roles in various industries, each with its unique set of features and applications. Understanding the distinctions between them can help you make informed decisions when selecting the right valve for your specific needs. So, let’s dive in and explore the world of floating ball valves and trunnion mounted ball valves, comparing their structures, functions, and ideal use cases to help you make the best choice for your operations.
What Are Floating Ball Valves?
Floating ball valves, as the name implies, have a ball that flows inside the valve’s body. The ball is attached to a stem that is controlled by a handle. The ball is linked to a lever that controls the valve’s opening and closing. Floating ball valves are utilized in numerous industries, including oil and gas, chemical processing, and water treatment.
Floating ball valves are often used in applications with high accuracy. A floating ball valve’s ball is free to move up and down, allowing it to form a tight seal. Floating ball valves are therefore excellent for applications where a tiny amount of leakage is acceptable.
Floating ball valves come in a variety of materials, including brass, stainless steel, and plastic. The material utilized will be determined by the application of the valve. For example, a plastic floating ball valve would best suit an acidic environment, while a brass ball valve would be best for a high-temperature application.
How Does Floating Ball Valves Work?
A floating ball valve is made up of three major components:
§ An actuator lever
§ A stem
§ A floating ball
The actuator lever is the outermost part to open or shut off fluid flow. When turned within a 90-degree angle, it rotates the stem, which turns the ball into an open or closed position.
The ball remains unmounted at the valve’s base, supported only by a stationary polymer ring and seats.
When the valve is closed, medium pressure forces the ball against the seats. This will provide a tight seal and stop the flow immediately. However, given that the ball is unsupported, high-pressure levels cannot be distributed to a base to lessen the force on the ball. As a result, a floating ball valve is only suitable for low to medium-pressure applications with ordinary temperatures.
A quality floating ball valve should have an anti-static and anti-blow-out stem design for overflow management and leakage control. This implies that even when pressure is raised or when fluid surges occur, the stem will remain in place with no leaks. A flexible soft seat is essential as it creates sealing around the floating ball to stop media flow.
The Benefits and Drawbacks of a Floating Ball Valve
A floating ball valve is commonly utilized in a wide range of industrial and commercial applications. The ball in this type of valve is designed to float on top of the fluid, allowing for a tight seal while using minimal force. While floating ball valves have numerous advantages, they also have a few disadvantages.
PROS
· It is suitable for a wide spectrum of fluids.
· Easy to operate
· Good for tight spaces
· Low maintenance
CONS
· Certain fluids may cause the ball to stick.
· It can be difficult to repair
· Not suitable for high-pressure applications
Applications of a Floating Ball Valve
Emergency shut-off systems- Pipeline systems, such as those involving fuels, water, or critical gases, often require a fast-responding shut-off valve in emergencies. This type of ball valve is unmounted, so 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 water flow. Water flow must also be managed to avoid overflows. Because it is pressure-sensitive and may open and shut as needed based on pressure circumstances, a floating ball valve is an excellent choice for water system control.
Pipeline pressure relief– Pipeline pressure relief- Pipeline pressure control is critical to avoiding pipeline breaks and other disasters. A floating ball valve can be added in a pipeline as a pressure outlet valve as it takes on the pressure while remaining intact, instead of a mounted ball valve that could sometimes blow out.
What are Trunnion Mounted Ball Valves?
A trunnion ball valve is a valve that uses a ball that is kept in place by two trunnions or posts. The ball in this design can rotate in place, allowing the valve to open or close. This ball valve is a sort of specialized valve used in a range of industries. These valves are engineered to deliver exceptional performance in essential applications. Trunnion ball valves come in a variety of sizes and pressure ratings to meet the needs of various industries.
Some industries that commonly use trunnion ball valves include the oil and gas, power generation, and chemical processing industries. These valves are also commonly employed in applications that require a high-quality valve that can tolerate high temperatures and pressures.
How Do Trunnion Mounted Ball Valves Work?
A trunnion ball valve consists of 4 main parts:
§ An actuator lever
§ A stem
§ A ball
§ A trunnion
The trunnion serves as the foundation for the ball. At the top end, the ball is linked to the stem and connected to an exterior actuator lever. A flanged trunnion ball valve has spring-loaded seats and a polymer ring insert between the trunnion and the ball. To keep the ball in place, the springs apply pressure to it. Together with the polymer ring, they also reduce friction when the ball rotates.
The ball is made hollow in the middle to facilitate the media flow. It can be either full bore or half bore. A full bore is a ball with the same hollow diameter as the pipeline it is put in. The diameter of the hollow part of the ball is smaller than the diameter of the pipeline in a partial bore.
When the actuator is twisted, the stem to which it is linked likewise turns. These actions cause the ball to rotate to an open or closed position on the trunnion. Seals in the seats and stem prevent fluid from leaking out of the pipeline during and after fluid flow. An adjustable gland packing box also helps the valve take on different pressure capacities. A conventional trunnion ball valve would additionally contain two bleeders for depressurization purposes.
A trunnion ball valve’s construction makes it suited for use in high-pressure and high-temperature fluid management applications.
The Benefits and Drawbacks of a Trunnion Ball Valve
Trunnion ball valves are one of the most popular on the market today. They are used in various industries and applications, from oil and gas to water and wastewater. But what are the advantages and disadvantages of trunnion ball valves?
PROS:
§ Trunnion ball valves are extremely strong and can sustain extreme pressure.
§ They are simple to use and open and close rapidly.
§ Trunnion ball valves have a good seal and can be used with various liquids and gasses.
CONS:
§ Trunnion ball valves can be expensive.
§ If they break, they can be difficult to repair.
§ Trunnion ball valves can be huge and unwieldy, making installation challenging in some situations.
Applications of Trunnion Mounted Ball Valve
· Chemical manufacturing plants. Chemical transfer through pipelines during production necessitates strict management. Corrosive chemicals are used because leaks and high reactive temperatures could endanger employees or the environment. Trunnion ball valves are perfect for securely managing such fluids due to the full-proof sealing applied during production and their high-temperature durability.
· Petroleum industry applications. API 6D trunnion ball valves are suggested for petrochemical sector applications because they are leak-proof and can withstand high pressure. These features are especially useful in high-volume petrochemical pipelines and gas lines requiring careful pressure management.
· Power generation. Power is generated using different fuels. Geothermal power, for example, is produced using steam, whereas hydropower is produced using water.
The material utilized to create electricity must be released into the system in measured units in each circumstance. Because of its ability to handle large-scale, high-temperature, and high-pressure activities, a trunnion ball valve is ideal for managing the flow of such media.
The Primary Distinctions Between Floating Ball Valves and Trunnion Mounted Ball Valves
Ball valves are classified into two types: floating ball valves and trunnion ball valves. Ball valves are valves that control the flow of fluid by using a ball. When the valve opens, fluid can pass through a hole in the center of the ball. When the valve is closed, the ball rotates, obstructing the hole and preventing fluid from passing through.
So, what are the critical differences between a trunnion and a floating valve? The biggest distinction is in the ball’s design. In a floating ball valve, the ball is free to float within the valve’s body. This aligns the ball with the seat, resulting in a tight seal. The ball in a trunnion ball valve is connected to a trunnion, which is a short, cylindrical piece of metal. The trunnion acts as a pivot point for the ball. This advantage is that it strengthens the valve and can prevent the ball from breaking or deforming under high pressure.
Floating ball valves are less likely to leak and easier to maintain than trunnion ball valves. They are also less expensive. Trunnion ball valves, on the other hand, have excellent flow characteristics and can withstand larger pressures.
