The design of the bellows seal globe valve is better than that of the ordinary globe valve. So, what are the advantages of bellows seal globe valves compared with ordinary ones?
1. The bellows sealed globe valve has no leakage and is applied to high-risk medium.
2. The regular globe valve is sealed with packing, and a slide will occur between the valve stem and packing so that the valve is easy to leak at low temperature.
3. Bellows sealed globe valves use closed bellows which can be stretched and compressed to replace packing seals, effectively preventing leakage caused by packing losses. Generally, these valves are used for transmission of the medium with strong permeability. For instance, there is usually no leakage occuring to bellows seal globe valves for the hydrogen system, as long as bellows are not damaged. However, the common globe valve is sealed with packing, which is easy to cause leakage.
4. The bellows sealed globe valve can cut off the flow of media and the opening or closing stroke of the valve stem is relatively short. Because the change of the seat opening is proportional to the stroke of the disc, the valve is an ideal choice for flow regulation. Therefore, this type of valve is very suitable for regulating or cutting off the flow, and for throttling.
Advantages of bellows sealed globe valves
1. Double seals (bellows+packing). If bellows fails, valve stem packing will avoid leakage. And the sealing meets international standards.
2. No fluid loss and energy loss reduction.
3. Long service life, reducing maintenance frequency and operating costs.
4. The robust bellows seal ensures zero leakage of the valve stem and provides maintenance-free.
5. PTFE soft seal materials are used for the valve seat for gas media to improve the sealing of the valve.
6. The valve seat with high temperature resistance (≤425℃) adopts the conical surface and hard sealing.
There is no comparison in the level of safety and the ability to control emissions of hazardous chemicals, between a well designed Bellows Seal globe valve and your standard ball and plug valves. Any chemical producer who wants to have the safety of its workers at the top of its agenda, should always be looking to fit the best possible protection against all leaks of dangerous hazardous chemicals. Bellows Sealed Valve design have been accepted as the best practical method for ensuring repeatable tight shut off and preventing leaks via valve spindles and body joints. There are good reasons why Eur Chlor members use Bellows Sealed Globe Valves.