The bellows globe valve, also known as the bellows-sealed globe valve, is designed to form a metal barrier between the fluid medium and the atmosphere by automatic roll welding to ensure zero leakage from the stem. Compared to traditional globe valves it has the following advantages.
①Double sealing design (bellows + packing) If the bellows fail, the stem packing will also be avoided; the robust bellows sealing design ensures zero leakage from the stem and provides maintenance-free conditions.
②Reasonable structure, reliable sealing, excellent performance, and beautiful shape.
③No fluid loss, reducing energy loss, and improving plant equipment safety.
④Co-based hard alloy overlay on the sealing surface, wear-resistant, corrosion-resistant, good anti-friction performance, long service life, reducing the number of repairs and lowering operating costs.
⑤Robust bellows seal design ensures zero leakage from the stem and provides maintenance-free conditions.
⑥Bellows globe valve stem tempering and surface nitriding treatment, with good anti-corrosion and anti-friction properties.
Globe valve, also called shut-off valve, is one of the most widely used valves, it is popular because the opening and closing process of friction between the sealing surface is small and more durable, the opening height is not large, easy to manufacture, easy maintenance, not only for low and medium pressure but also for high pressure.
The closing principle of the globe valve is that it relies on the pressure of the valve bar to make the sealing surface of the valve flap and the sealing surface of the valve seat fit closely together and stop the flow of the medium.
The globe valve only allows the medium to flow in one direction and is installed with directionality. The structure of the globe valve is longer than the gate valve, while the fluid resistance is high and the sealing reliability is not strong during long-term operation.
①The structure of the globe valve is simpler than that of the gate valve, and it is more convenient to manufacture and maintain.
②sealing surface is not easy to wear and abrasion, has good sealing, no relative sliding between the valve flap and body sealing surface when opening and closing, so wear and abrasion are not serious, good sealing performance, and long service life.
③When opening and closing, the valve flap stroke is small, so the height of the globe valve is smaller than the gate valve, but the length of the structure is longer than the gate valve.
④opening and closing torque, opening and closing more laborious, opening and closing time headmaster.
⑤fluid resistance, because the valve body media channel is more tortuous, fluid resistance, power consumption.
⑥media flow direction nominal pressure PN ≤ 16MPa, the general use of downstream, the media from the direction of upward flow under the valve flap; nominal pressure PN ≥ 20MPa, the general use of counterflow, the media from the valve flap downward flow. To increase the sealing energy. Use, the shut-off valve media can only flow in one direction, and can not change the direction of flow.
⑦fully open when the valve flap is often eroded.
①fluid resistance, open and close when the force is required.
②not suitable for with particles, viscosity, and easy to coking media.
③the adjustment performance is poor.
In industrial use, the globe valve caused by leakage: high temperature, highly toxic, flammable and explosive, radioactive media, etc., not only pollute the environment but also often causes significant personal and property damage.
Bellows seal globe valve using the bellows seal design completely eliminates the common globe valve stem packing seal aging fast easy to leak shortcomings, bellows globe valve not only improves the use of energy efficiency, increases the safety of production equipment, reduces maintenance costs and frequent maintenance, but also provides a clean and safe working environment.