What is a globe valve?
A globe valve is a linear motion valve and used for control, regulate, start or stop the flow inside the piping system of the fluid. The disk of the globe valve can be totally pulled out from the way of fluid flow and it has perpendicular to the flow motion. This is the reason for great throttling capability. Due to this open 100% flow path for fluid reduces the chance of pressure drop.
It is mainly used for linear motion applications and it is not used for low pressure applications because of its pressure drop of the liquid. It is used for pressure drop is a part of the process system or pressure drop does not play an important role in operations. This type of valve is used for very high pressure and applications and is mostly used in oil and gas, petrochemical and chemicals industries. Mostly suitable for throttling and controlling the flow of the system but not suitable for big bore piping applications. Here are measures of disadvantages of the globe valve as it has slow operations as compared to other types of valves like ball valves.
What are the types of globe valves?
On the biases of body construction and flow direction, there are three types of globe valves. On the biases of the boat and its body
- Z type globe valve
- Y type globe valve
- Angle type globe valve
What are the parts of a globe valve?
There are many parts used in the construction of globe valves on the basis of its construction body, valves general parts are mentioned below: Handles, wheels, wheel lock nut, stem, gland nuts, gland packing, or other types of packing, packing followers, discs, seat rings, bodies, bonnets and body flanges.
What is the function of the globe valve?
The globe valve is used for start, regulate and stop the flow of inside piping fluid or any other medium. Currently there are many types of globe valves available in the industry depending on its construction and features, in the above section that tern has already mentioned please check the same.
What are the advantages and disadvantages of globe valves?
There are many advantages and disadvantages of globe valve some of this is mentioned below.
Advantages of globe valve
- Good shutoff capability
- Very good throttling capability
Disadvantages of globe valve
- More pressure drops as compared to other types of valves
- Large size, heavy weight, and expansive as compared to gate valve
What is the difference between ball valve and globe valve?
Globe valve is used to regulate, start or start the flow whereas the ball valve is used for control without any pressure drop. A globe valve is used with the plugs (disk) to control the flow and other hands in the ball valve super finished, polished ball used to control the flow. The operating duration of the globe valve is very poor than the ball valve, because the ball valve is a quarter turn valve and it will be able to quickly open and close the application but both valves are available in solenoid, electrical motorized, pneumatic controls and manual. A globe valve is also known as a control valve. The globe valve requires a large space for installation in a vertical position but the ball valve requires a large space horizontally for installation. If you want to isolate the flow for a long time you have to use a gate valve. The globe valve is used to regulate cooling systems and steam services. The ball valve is heavier than the globe valve for the same size and features. Pressure drop in the ball valve is very low whereas in the globe valve pressure drop is a major disadvantage.
What are globe valves used for?
globe valves uses
The reason we can use the globe valve to regulate flow is because as we open the valve it travels linearly upwards and as it moves away from the port, we are proportionally allowing more and more flow through the valve. We can see that as a rising stem, the rising stem indicates the valve position. Now the valve is open we can see that the stem is popped out of the top and if the stem of the valve goes down it indicates that the valve is closed. We can also see that the valve is mechanically actuated because we’re using a hand wheel.
How to solve gland leaking problems in globe valves?
Gland follower We tighten up a bolt of follower plates going to push down on the gland or packing. And as we do that, we’re going to put pressure onto that area packing and as this is compressed. The packing is going to be squeezed against the stem and filled empty are inside the stem bonnet, and that’s why it gives us a seal (prevent the liquids from coming out). This prevents the valve from leaking out through the top of the bonnet. If we over tighten the follower, then we are going to squeeze the packing very tight against the stem. It makes the valve hard to operate, we run the risk of damaging the packing and we also run the risk of damaging the stem that goes down the stem.
Where is the globe valve used?
Globe valve is used in plant piping with motorized solenoids, pneumatics and manual control systems. As you know this type of valve is used for controlling the flow, stopping the flow and regulating the flow. It is mostly used for high pressure, and steam services. It can be installed vertically and horizontally in both directions but as per requirement. Globe valve is a unidirectional valve and during installation indication should be followed. Please read more in my next blog.