Design of the globe valve

Globe Valve Construction

• Closure element (flat disc, cylindrical, conical, or radial)
• Threaded rod/spindle made of steel or stainless steel
• Housing (straight or angled made of cast iron, steel, or bronze)
• Actuator (handwheel or electric drive)

Three types of globe valve constructions based on stem sealing

The gland packing stem sealing is the simplest and most common globe valve construction, characterized by low cost, repairability, and the need for maintenance.

The tightness of the stem sealing is achieved by a soft stuffing (gland packing), which fills the space between the moving stem and the valve body. The packing is compressed by the gland sleeve and requires periodic tightening and replacement over time.

Globe valves with gland packing stem sealing are used in water and steam pipelines.

The bellows stem sealing is characterized by high reliability, complete tightness, does not require maintenance, but has a higher cost than globe valves with gland packing.

The complete tightness of the sealing is ensured by a bellows made of stainless steel, which separates the cavity of the valve body in contact with the working environment from the valve cover, on which the stationary nut of the stem is fixed.

Globe valves with bellows stem sealing are used in pipelines transporting water, steam, compressed air.

Diaphragm seal valve is characterized by complete tightness, high reliability, simple shape of the flow part, high cost, and usually low temperatures of the working environment.

Diaphragm valves are used for water supply water, viscous and gaseous media.

By body material

Cast iron valves, as general-purpose shut-off valves, have the widest application. They are made in flanged or threaded versions, distinguished by accessibility and low cost, but cast iron is a brittle metal prone to corrosion.

Steel valves are made in flanged versions and are more often used in technological installations with high parameters of the working environment and high reliability requirements. Steel valves, like cast iron ones, are prone to corrosion, but steel is more ductile.

Bronze and brass valves are mainly made in threaded versions and are distinguished by high corrosion resistance, which allows them to be used in heating, cold and hot water supply systems.

By type of control

Handwheels are used to control the valve manually, while gear electric drives are used for automatic control.

Valves with electric drives are used for automation of the technological process, remote control, as well as for valves with a large conditional passage diameter.

To open the valve, a large number of revolutions of the electric drive are required, which allows the use of low-power electric drives, but excludes the possibility of quick opening or closing. This feature makes it impossible to use valves with electric drives for fast flow shut-off, but gives them a great advantage in systems that do not allow hydraulic shocks.

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