Hard seal eccentric semi-ball valve uses the common path of eccentric body, eccentric ball, seat and stem for centring when they make rotational motion. It is tighter during closing to realize sealing. The ball is separated from seat completely, eliminating the abrasion of sealing ring and overcoming the abrasion between conventional seat and body. Nonmetal elastic materials are implanted into metal seat so that the metal face of seat can be protected. The valve is quite suitable for fiber, tiny solid particles, pulp, coal ash, oil and petroleum.
In terms of structure, hard seal eccentric semi-ball valve is classified into up-load and side mount:
1. Up-load: up-load mainly focuses on media having strong erosion wearing. The structure is convenient for repairing when change damaged closure member. The valve does not need to be dismantled from the pipes, saving time and cost.
2. Side mount: side mount has compact structure and light weight, quite suitable for the situation having limited installation space.
Feature of hard seal eccentric semi-ball valve
1. The structure uses eccentric deed to realize tightening, regulation and closing through transmission mechanism. Due to double eccentricity, valve plug hides inside ball during closing. The valve has large actual internal area, in case of being eroded. When the valve is on, the surface of plug advances along with seat gradually, effectively eliminating scaling and realizing reliable sealing.
2. The balls use duplex metal and base metal is bead welded with different alloys. The seat is also processed by using bead welding. The sealing face has corrosion resistance, wearing resistance and high strength, meeting different requirements.
3. The valve has closed sealing. It can realize non-leakage when transmitting harmful gas.
4. The plug of sealing pair maintains compensation. After seat being wear, just only rotate a little during closing, which can realize reliable sealing and extend service life. Moreover, the seat is still available when gland nuts are turned off, adjusted or changed.
