In this article, PIF speaks to leading Scottish valve distributor, BM Engineering Supplies, to discover the main differences and similarities between ball valves versus globe valves. Here, we put these two popular flow control valve types head to head as we find out which is most suitable for your application.
Before we investigate the differences between ball and globe valves, we asked Scott Miller of BM Engineering to explain how both valve types work. “Ball valves are a type of quarter-turn valve which use a hollow, perforated and pivoting ball to control flow through it”, explains Scott. “It opens when the hole of the ball is in line with the flow and closes once pivoted 90-degrees by the valves handle. The handle lies flat in alignment with the flow whilst open and perpendicular once closed. This allows for easy visual confirmation of the ball valves status”.
“Once the industry standard for many years, globe valves were often the control valve of choice for manufacturers”, explains Scott. “Named for their spherical body shape, globe valves feature bodies with two separated halves by an internal baffle. This has an opening that forms onto seat onto which moveable plus or discs can be screwed in to close the valve. Most automated glove valves typically use smoother stems as opposed to threaded ones, as well as opening and closing using an actuator assembly”.
The primary difference between a ball valve and a gate valve is how they close. “Ball valves feature a stem and a ball that both turn horizontally, hence why they are commonly known as rotational valves”, continues Scott. “While glove valves have a stem and a plug which strokes linearly, giving them their other name of stroke valve. With this in mind, ball valves are often preferred for applications requiring on/off control without drops, while globe valves are better at regulating flow”.
Both valve types have their strengths and weaknesses. As to which is better, purely depends on your application requirements. As PIF has previously covered, ball valves are durable control valves, capable of performing well after many cycles and closing securely after long periods of disuse. Such qualities make them better choices than globe valves for shut-off applications. However, ball valves lack the fine control in throttling applications offered by globe valves.
To find out more about ball valves and globe valves from BM Engineering Supplies, visit their website.