Valves are an integral part of any piping system, whether that be a compressed air system or for conveying liquids and other gases. They are typically used to control and regulate the media in question.
Globe valves and ball valves are two of the most common types of valves found across industries. They have significant differences in their design, mechanisms, applications, and more, and so, this article will provide you with all the relevant information on both!
Table of Contents
- What is a Globe Valve?
- What is a Ball Valve?
- The Differences Between Globe Valves & Ball Valves
- FAQs (Frequently Asked Questions)
What is a Globe Valve?
The globe valve is a member of the linear motion valve family and is aptly named because its body design typically represents the shape of the globe. Its key function is stopping and starting the flow of a medium as well as being able to regulate it.
These types of valves offer a tight seal with little chance of leakage. Modern globe valves may adopt varying body shapes like a plug-like disc which allows or blocks the flow. Globe valves are great for throttling flow too, given that their seats are parallel to the flow. They do not erode when on but can be liable to high-pressure drops due to their design.
Here’s an example of a globe valve readily available on Amazon!
Globe Valve Advantages
- Capable of regulating and throttling flow
- Resist erosion
- Tight seal
Globe Valve Disadvantages
- Can only be installed in one direction
- Liable to high-pressure drops
- More expensive than similarly sized gate valves
What is a Ball Valve?
Ball valves are one of the most user-friendly control elements in a compressed air system. These valves are inexpensive, reliable, and easy to operate. A ball valve is a shutoff valve used to control the flow of a medium by utilizing a rotary ball that has a bore. The flow of the medium is allowed to either flow through it or be blocked by the 90-degree rotation of the ball inside the valve.
Ball valves are generally known for their long life span and the ability to provide reliable sealing, even when the valve has not been in use for a long time. On top of this, they boast good resistance against contaminated mediums compared to other types of valves.
Here’s an example of a ball valve readily available on Amazon!
Ball Valve Advantages
- Realiable sealing
- Resistant against contaminants
Ball Valve Disadvantages
- Liable to erosion when partially exposed
- Limited accuracy of controlling flow rate including throttling
- When used with water they trap water in the center cavity when in a closed position
The Differences Between Globe Valves & Ball Valves
Given the definitions of the globe valve and ball valve, along with their advantages and disadvantages, you should have a good idea already about the differences between them. But, I would like to dig into it a bit further and focus on the following differences:
One of the biggest differences between the two types of valves is their design. Ball valves have a stem and ball that move horizontally and are generally referred to as “rotational” valves. Globe valves, on the other hand, have a stem and plug that strokes linearly (vertically), giving them their other name of “stroke” valves.
Globe valves use a plug (stem) that closes against the flow of the medium, and a ball valve has a gate (ball) that closes across the flow. Ball valves are ideally designed for systems that need on/off power without pressure drop. While globe valves are designed for regulating flow and acting as a control valve.
A globe valve, named for its spherical shape, has a movable plug or disc that moves parallel to the medium flow. The disc within the globe valve is designed to move up and down from the seat and a full flow means that the disc only needs to move slightly from the seat. These valves are designed to allow throttling.
These parallel vertical movements allow the space between the disc and the seat to change ever so slowly when the valve starts to close, which in turn gives the valve the good throttling ability it has and also allows it to regulate the flow within a pipeline which can often be desirable.
Ball valves on the other hand are designed with a ball inside their valve. This ball is a form of quarter-turn which uses a hollow, perforated, and pivoting ball to enable it to control flow through it. When the hole is in line with the flow, the valve is open, and then the valve can be closed by pivoting the valve handle 90-degrees.
Typically ball valve handles will lie flat and in the alignment of the flow when they’re open and then perpendicular to the flow when closed, making it easy to know the valve’s status.
Ball valves are generally the least expensive of any valve configuration and not only that, but they have low maintenance costs. The price difference between ball and globe valves may be quite small until the size of the valves become large and then, globe valves will typically be a bit pricier than ball valves of the same specifications.
Ball valves are typically suited for keeping flow closed for long periods of time, and work efficiently with high-pressure systems like a fire-hose. Globe valves are suited to systems that require regulation and control of the flow. Cooling systems, fuel, and steam systems are a few examples of where globe valves are commonly used.
Globe valves are commonly found in residential water services also and generally do not represent a good choice for compressed air services.
FAQs (Frequently Asked Questions)
Globe valves are suited to applications where flow rate control and open/close operation are desired. They are primarily used in scenarios where throttling is required. It’s as simple as turning the handle of a globe valve to adjust the rate at which the flow of the medium flows through the valve.
One of the biggest advantages of globe valves is their ability to throttle or modulate flow. Some valves, like ball valves or gate valves, are only capable of being open or closed. Globe valves, however, are capable of being open or closed and partially open. Being partially open can allow you to adjust the flow of the medium without stopping it.
Ball valves are very robust products that work well over a long life span. They remain stable and reliable, firmly operating and closing even after extended periods of disuse. These characteristics make them an ideal option for shut-off applications, where they are sometimes favored to other types of valves like gate valves or globe valves. On the other hand, ball valves may not provide the finest control in the throttling applications that globe valves excel in.
Additional valve reading:
- Types of Compressed Air Valves – Guide To Pneumatic Valves
- Pneumatic Flow Control Valves – What Are They, How Do They Work?
- Air Compressor Air Line Non-Return valves/Inline (In The Air Line) Air Check Valves Explained
- Check Valve Sizes
- What is Check Valve Cracking Pressure
- Air Compressor Troubleshooting Check Valve
- Air Compressor Unloader Valve Explained
- Unloader Valves On Twin V Piston Compressor Guide
- 5 3 Valves Explained
- 5-2 Air Valves
- 4-2 Compressed Air Valves
- 3-2 Air Valves
- Drawing a 5/3 compressed air valve
- Draw A 5/2 Air Valve
- Pneumatic Soft Start Valves
- Solenoid Pilot Air Valves
- Compressed Air Solenoid Valve Guide
- Air Compressor Auto Drain Valves Guide
- Needle Valve vs Ball Valve
- Globe Valve vs Gate Valve
- Butterfly Valve vs Gate Valve
If you have any questions regarding globe valves vs ball valves, please leave a comment below, with a photo if applicable, so that someone can help you!