Ball Valves and Globe Valves are shut-off valves typically used in piping systems. However, it usually takes time to determine which is most suitable for an application. System design should be completed before deciding on the optimum valve for the task in terms of cost, installation area, flow control, and other factors. Continue reading to learn why a Globe Valve may be better than a Ball Valve.
Working Principles
Globe Valve Working Principles
A Globe Valve is a multi-turn valve, meaning that the handwheel needs to be turned more than 360º to open or close the valve fully. A globe valve’s essential components include the valve body, bonnet, handwheel, stem, and plug. Media enters the valve body through an inlet and departs via an outlet.
The bonnet protects the valve’s threaded components and connects to the valve body. The threaded stem raises or lowers the plug when the user cranks the handwheel. Raising the plug opens the aperture and allows media to flow.
Lowering the plug into the valve seat closes the orifice and stops the flow. In contrast, elevating the disc boosts the flow rate. The flow rate peaks when the disc is elevated to its highest position. The fluid flow rate is adjusted by moving the disc via the stem.
Ball Valve Working Principles
A Ball Valve is a quarter-turn valve, meaning that the handle only needs a 90º turn to open or close the valve. The figure shows the basic components of a ball valve. The stem connects to the ball. The ball sits on the ball valve seat, creating the seal.
O-ring stem seals are used to prevent leakage. All of these components are found within the valve housing. The ball has a bore going through it. In normal functioning, the bore is either parallel to the valve ports, allowing flow, or perpendicular to the ports, preventing flow. For more information on how Ball Valves operate, see our page.
Flow Control
Globe and ball valves are both used to switch on and off the flow. Globe valves can also be partially open or closed to adjust flow. This flow management is possible because the globe valve’s disk sits parallel to the flow. Globe valves attain higher linear flow rates than ball valves, which decreases the impact of the water hammer.
Head Loss
Globe valves have much larger pressure loss in the completely open position compared to ball valves. This is because the fluid must reverse direction several times when it flows through a globe valve.
Valve Design
Globe Valve Design
Globe Valves are available in three basic configurations: T- or Z Globe valve, Y- Globe valve, and angle Globe Valve. Read our post on Globe Valves to learn more about each variety.
Ball Valve Design
The Ball Valve is categorized into many types based on its housing construction, ball design, and port size. Depending on the housing construction, At Aira Euro Automation we manufacture 1, 2, or 3-piece ball valves. Ball valves are classified as full port, standard port, or reduced port based on the size of their ports. Ball valves are classed into two types based on the number of ports: two-way and multiport.
Applications
Globe Valves are used to control fluid flow. Furthermore, globe valves are advantageous in applications requiring precise throttling. Ball Valves, on the other hand, are commonly used for plumbing system shut-off and isolation. Industrial applications for globe valves include fuel oil systems and cooling water systems, while those of Ball Valves include chemical storage and natural gas industries.
Ball Valve and Globe Valve Similarities
Globe Valves and Ball Valves share some similarities. Both valves are used in pipe systems to regulate the flow of liquids and gases. Both are shut-off valves used to allow or prevent fluid passage via a pipe. Globe and ball valves can be controlled either manually or mechanically.
Advantages and disadvantages of Ball valves vs. Globe valves.
Operation: Operation: Ball valves are simpler to use than globe valves.
Throttling: Globe valves are ideal for throttling activities, whereas ball valves should be fully closed or fully open.
Handle: Ball Valves are quarter-turn valves which means the ball valve handle must be turned by 90º to go from fully open to a fully closed state or vice versa. The handwheel of globe valves must be rotated several times from completely closed to fully open.
Cost: Ball valves are less expensive than globe valves due to their simpler design.
Space: Globe valves use more area than ball valves.
Pressure Ratings: Ball valves can withstand more pressure than globe valves.
Durability: Ball valves survive longer than globe valves.
Leakages: Globe valves are more likely to leak than ball valves.
Media Flow Resistance: A globe valve is more resistant to media flow than a ball valve.
Head Loss: Globe valves have a greater head loss than ball valves.
What to choose Ball valve or Globe Valve
The intended function determines whether to use a ball valve or a globe valve. The important considerations to make throughout the selection process are outlined below:
Flow Rate: Ball Valves are ideal for applications requiring a high flow rate due to their full-bore design.
Pressure Drops: Ball valves have reduced pressure drops since the flow passes directly through them.
Maintenance: Ball valves are simple to maintain since they require just a little amount of oil to keep clean. Further maintenance is required when debris accumulates.
Temperature: Ball Valves perform better in high-temperature environments due to their sturdy structure.
Conclusion
Choosing the right valve is crucial when designing a pipe system. Globe and ball valves are two of the most often utilized valves in the oil and gas sector. While both have advantages, globe valves are ideal for situations that need a tight seal, such as high-pressure systems.
Ball valves are ideal for applications that require a speedy shut-off, such as emergency shutdown systems. When seeking for a commercial valve, trust Aira Euro Automation, India’s foremost valve manufacturer, to provide the highest quality Globe Valves, Ball Valves, Gate Valves, Butterfly Valves, Pnumatic Control Valves, and Plug Valves. Our skilled expert team can help you select the correct valve for your application.