The globe valve is a forced sealing valve. The closing member (disc) moves along the centerline of the globe valve seat. The opening and closing parts of the globe valve are plug-shaped discs, the sealing surface is flat or conical, and the disc moves linearly along the center line of the valve seat.
There are many types of globe valves. According to the valve body design, globe valves can be divided into three categories: Tee(T), Angle, and Wye(Y).
Tee(T) Globe Valve
T type globe valve is the most commonly used globe valves, but the flow resistance is the highest, which is generated by the tortuous flow path of this form of valve body among the above forms. The T-shaped body has low flow and high pressure drop. They can be used for quick throttling, such as on a bypass around a control valve. T-shaped bodies can also be used where only throttling is required without regard to pressure drop.
The shape of the T-shaped valve body has three structures. The S-shaped structure, the waist drum-shaped structure and the Z-shaped structure (spherical heart shape). The T-shaped valve body is a straight-through flow channel.
The Angle Globe Valve
The angle globe valve is a modification of the basic standard pattern globe valve. It’s opening and closing parts are plug-shaped valve discs. The sealing surface is flat or conical, and the flap travels linearly down the fluid’s centreline. The ends of this globe valve are at a 90-degree angle, and fluid flow is accomplished with a single 90-degree turn. Their coefficient of flow is significantly small. The angle globe valves have a streamlined curved bore. Packing flushing and heating steam jackets are useful to avoid accumulation and crystallization of the medium.
The Wye(Y) Globe Valve
Wye globe valves can regulate, open and close fluid flow. These valves are also known as inclined globe valves. This type is an alternative to the high pressure drop commonly found in ball valves. The seat and stem are angled at 45°, providing a straighter flow path and minimal flow resistance when fully open.
This design is typically used for throttling during seasonal or start-up operations. They are used in high pressure and no pressure drop are required. Wye globe valve can reduce pressure drop problems and its position in the piping system is not restricted due to the low fluid resistance. Wye globe valve stem and seat provide a straight flow path when fully open, which helps reduce fluid flow resistance. Wye globe valve uses soft seat or metal seat. Soft seats are used for low temperatures up to 60°C, while metal seats are used for high temperatures above 60°C.
Different body designs reflect different characteristics, and pay attention to the characteristics of various valves.