The selection of the correct valve is essential, as each one varies in its characteristics and purpose. Of them, only some have two states: open or closed. Fluid flow and pressure can be modulated by some. Different valves can also result in varying amounts of pressure loss. The needed features depend on the situation. Both of gate and globe are suitable for fire protection as fire main gate valve.
The globe valve is one of the most common types of valves. This article provides an explanation of the working of globe valves, along with their pros and cons. We look at the different shapes of globe valves and compare them to other types of devices such as gate valves and ball valves, then.
How Does A Globe Valve Work, And What Is It?
When selecting a globe valve for your application, consider its three key features. Lateral movement valves open or close based on the up-and-down movement of a stem, meaning they are activated by this motion. They allow, stop, or throttle fluid flow, second. Globe valves can throttle flow without completely ceasing it, in contrast to some valves that only have open and closed states. A tradeoff for the throttling services, thirdly, they cause significant head losses compared to other valves.
What is the process of how globe valves work?
There are three parts to a globe valve from the outside: a handwheel, a bonnet, and a body. When the handwheel is turned, the stem housed in the bonnet screws up and down. Depending on the need, the end of the stem has a small component called a disk or plug which may come in different shapes and can be either metallic or non-metallic. The valve is named for the globe-shaped body that houses a seat. A metal frame seat is used to divide the body into two chambers, with a hole for fluid to pass through. If the valve is opened, the opening in the seat will allow fluid to flow upwards. The seat’s opening is blocked when the stem is screwed down until the disk closes it.
Globe valves have the ability to throttle or modulate flow, which is one of their main advantages. They can be partially open in addition to being either closed or open. You can adjust the flow without completely halting it by using this. A major downside of globe valves is the relatively high head loss that they cause. The amount of resistance a liquid encounters as it flows through pipes is referred to as head loss or pressure loss. The greater the resistance, the more pressure that is lost. This loss is caused by gravity, friction of the fluid against the walls of the pipe, and turbulence. Pressure loss is primarily caused by turbulence from valves and fittings.
Fluid passing through globe valves must change direction, leading to turbulence and a decrease in efficiency. The loss incurred can be determined by factors such as fluid velocity and friction factor. A metric called the L/D coefficient can be used to review the pressure losses from different valves, however.
By using its L/D coefficient, we can compare a valve to a straight section of pipe with the same friction factor. Length and diameter are represented by L and D, respectively. A section of pipe with a length-to-diameter ratio of 5 has the same friction loss (all else being equal) as a valve with an L/D ratio of 5. The higher the head loss created by a component, the larger its L/D.
A Gate Valve Is What
Gate valves are used for On-Off control and are generally cheaper than globe valves of the same size. Furthermore, gate valves are less prone to fluid trapping due to their design, whereas globe valves may have a larger amount of trapped fluid because of the direction of flow. We often find it out around firefighting protection. And call it as fire main gate valve.
What Difference Between A Globe Valve And A Gate Valve?
Fire main gate valve
1. Gate valves are commonly utilized in the oil and gas industry for use in plants. The piping system is designed only to start and stop the flow, however. Unfortunately, they won’t regulate flow.
2. Globe valves are designed differently than gate valves. These valves are designed with either a rising or a non-rising stem and have gate faces that are parallel or wedge shaped instead of a disc. Workers are able to understand when the valve is completely open or completely shut thanks to this.
Globe valves
1. The oil and gas industry is just one of many fields for which both globe valves and gate valves are designed for various applications. Each valve, however, does not serve the same function. In additional, Gate valves are also important for firefighting and fire protection. Normally, it is called fire protection gate valves.
2. Globe valves are typically employed for the purpose of stopping, starting, and controlling the flow of material through a pipe. They have a spherical body and a disc that make them up. The disc within the globe valve is designed to move vertically between the seat and its uppermost position. As the valve begins to close, these vertical movements facilitate a gradual alteration of the space between the disc and the seat. The valve’s good throttling ability, which enables it to regulate flow within a pipeline, is provided by this.