The problem's cause and characteristics of bellows globe valves

Bellows globe valves are usually referred to as "for the diaphragm valve, valve is a relatively new category, it has its own structure unique to some advantages, such as switch without friction, the sealing is not easy to wear and open-close torque is little. It can reduce the match of the specifications of the actuator. With multi-turn electric actuators, which can realize to adjust the medium and heavy cutting. Bellows Cast Steel Globe Valves, bellows seal design, completely eliminates the common valve stem packing seal aging fast easy leakage faults, not only improve energy use efficiency, increase production equipment safety, maintenance cost was decreased, and the frequent maintenance, also provides a clean and safe work environment.
Product features:
1, product rational structure, reliable sealing, excellent performance, beautiful appearance;
2, seal face Co carbide surfacing, wear-resisting, corrosion resistance, good friction resistance and long service life;
3, the valve stem conditioning and surface nitriding treatment, has the good corrosion resistance and friction resistance;
4, double seal, it is more reliable in performance.
5, the valve stem lifting position indicator more intuitive;
6, parts materials, the size of the flange and butt weld ends can be reasonable selection according to actual working condition or the user requirements, meet the needs of the various kinds of engineering.
Bellows High Pressure Globe Valves adopts the unique design of double bellows seal which completely eliminates the stem packing seal leakage problem, meet the most stringent leakage level requirements. Such as corrugated pipe failure, valve stem packing seal can provide secondary seal to prevent leakage.
Bellows seal structure not only to eliminate the phenomenon of leaking, and no need maintenance, such as the need to change the internal parts, convenient, simple, fast, and all the parts up to standard and interchangeable.
In the bonnet/bonnet with bonus oil injection hole, valve rod and the nut bushing lubrication.
Bellows seal globe valve adopts unique spherical cone valve core instead of the traditional flat valve core. Manual and rough water control, valve core surface hardening treatment, improves the sealing performance, 6 each of the following can be installed in vertical, the valve core to adjust.
Bellows globe valve is suitable for the nominal pressure PN1.6 ~ 6.4 MPa / 150 lb, working temperature - 29 ~ 425 ° of petroleum, chemical, pharmaceutical, electric power industries under different conditions, such as the pipeline, cut off or connect pipe medium.
Bellows globe valve leakage generally divided into leakage and leakage in the two cases, the cause of leakage. Leakage in general because the fluid contains solid ruined, caused by leakage is the main reason of the corrugated pipe rupture failure sealing boundary. Site usage analysis, main and valve stem leakage outside the structure, working environment and using the operating mode.
Bellows globe valve stem using corrugated pipe, and packing structure double sealing structure, corrugated pipe and the inner ring and outer ring welded bellows components, then with the valve stem and guide body welding, blocking medium through the valve stem leakage to outside. Stem up and down movement distance through the flat key I limit. Valve is closed, flat key I downward movement, until completely contact disc and seat. Open valve, flat key I upward movement, until the flat key I face with packing the face under contact. Because the packing used is PTFE material, material is soft, if excessive open valve, will lead to a flat key I embedded filler, the valve cannot be opened and closed again, and cracking bellows components, result in media leakage along the valve stem. Corrugated pipe tensile length and amount of compression is set according to the valve stroke, if exceed the limit tensile or compression, it could damage the corrugated pipe, corrugated pipe burst, seal failure. Therefore need to increase the spacing device of valve opening and closing, the valve opening and closing process, bellows expansion in the scope of design.