A bellow seal globe valve is a valve that is used in the control of fluid with tight sealing against leakage. It contains an elastic bellow section that is separated between the external environment and the inner mechanism of the valve that enhances sealing ability to be applied at high pressure and high temperature.

Working

1. Flow Control: Similar to any standard globe valve, fluid flow control in a bellow seal globe valve is through the raising or lowering of a disk (or plug) off against the seat in the valve body.
2. Bellow Mechanism: The bellow essentially forms a flexible barrier which prevents fluids from leaking along the length of the valve stem. When the valve is operated (either by handwheel or actuator), the bellow expands or contracts in order to maintain a tight seal.
3. Throttling Ability: Such design allows for precise throttling and flow regulation, thus offering the advantage to be suitable in applications requiring fine control.

Advantages

● Leak Prevention: The leakage potential of the bellow type is at its minimum, and they are therefore able to use hazardous or corrosive fluids.
● Longevity: Being made from high-grade materials, these valves can withstand extreme temperature and pressure.
● Maintenance-Free Valve: The bellow seal avoids packing and all types of maintenance.
● Multi-Media Serviceability: Can be applied to various types of media-gases, liquids, and steam.

Industries Using

● Chemical Processing: Controlling the flow of aggressive chemicals while preventing leakage in chemical processing.
● Oil and Gas: Managing the flow of the products in pipelines and refineries while reducing environmental damage.
● Pharmaceuticals: For applications requiring aseptic conditions as leakage could lead to contamination.
● Power Generation: Used in steam service lines and thermal power stations.
● Water Treatment: For applications where accurate flow and leakage-free operation is required.

Components

1. Casing Body: It is the outer shell of the valve that contains the inner parts and connects to piping.
2. Bonnet: An outer covering of the valve enclosing the inner mechanism and permits access for service.
3. Bellow: A flexible, seal able part preventing fluid leak along the stem.
4. Stem: A rod connects the handwheel or actuator to the disk permitting valve operation.
5. Disk/Plug: The one that moves to open or close a valve, thus varying fluid flow.
6. Seat: That surface where the disk presses, making the valve seal tight.
7. Handwheel/Actuator: That mechanism that assists in using a valve manually or automatically.

Description

1. Body Material: Cast Iron, Cast steel [LCB, LCC, WCB, WCC, WC6, WC9], Ductile Iron, Stainless Steel [CF8, CF8M, F3, F304, F316, F31L, F51, F55, F91, SS304, SS316, SS316L, SS904L]
2. Ends: Flanged, Buttweld, Socketweld, Threaded
3. Class: 150- 2500; PN25- PN450
4. Size: ½” to 24”