Double Block And Bleed Metal Seated Full Bore Ball Valve

Metal To Metal Seated Full Bore Ball Valve

Metal to metal sealed design has been employed perfectly for the ball and seat, which has also adopted the advanced hardening technolohies, such as ultro-sonic spray coating, nickel base spray welding, surface specially hardening, stellite spray welding. ceramic materiai with high strength and hardness, and so on.

Surface hardness of the ball and seat may generally reach more than HRC6O, Maximun is up to HRC74, amd application temperature of the material may be up to 540 Deg C Maximun is 980C. Combining strength of the material gets to more than 10000PSI. Beside, the surface material possces also very good resistance properties of friction and impact. Metal to metal sealed ball valves made by Coosai are suitable for use in most criticle working conditions.

• Valve stuck prevented under high temperature

In the case of high temperature working condition, the valve seat and ball would easily get stuck due to heat expansion, and the valve could not be open.

Metal to metal sealed ball valves made by Coosai Valve, employ the patented design of bevelling spring loading, which would absorb the heat expansion of parts caused by the bevelling spring. So, it is ensured that the valve would not get stuck and be open and close easily in the case of high temperature condition.

• Design Features of metal to metal sealed ball valve

Except for such features as wrong operation prevention, stem blow-out proof, mounting pad provied, the metal to metal sealed ball valves made by Coosai posses the following unique features.​

Natural anti- static structure

Metal to metal sealed ball valve with its body seat, ball, other metal parts,and so forth, closely contact with each other,having naturally formed a static electricity passage. In this respect, there is no need to provide special anti-static device.

• An Entire Fire Safe Structure

The metal to metal sealed structure has been adopted for the valve sealing surface design. Packing is also designed with graphite, and gasket is also designed with stainless steel, plus graphite that the valve can assure reliable tightness even if under fire condition.

• Excellent tightness function

A unique technique has been employed for the ball grinding, which makes the ball surface reach extreme round and smooth by rotating the ball and grinding apparatus at different directions in space. The tightness function of the valve meets completely and exceeds the standard requirement.

• Double block and bleed function

Coosai's metal to metal sealed trunnion ball valve is in general of the front ball sealing structure. Actually, Two seats of the metal to metal sealed trunnion ball valve can both cut off separately the medium atinlet and outlet to realize double-block function. When the valve is closed, the body cavity and both the bore ends can be blocked with each other even if both ends of the valve are under pressure at the same time ,Where as the medium left in the body cavity may relieve through.
Coosai's metal to metal sealed floating ball valve is of behind ball sealing structure, employing in general single direction tightness. The filow direction is indicated on the valve body. if specially required by customers, Coosai's patent of bi-direction Sealing design maybe selected.

• Advanced Hardening Technology Employed For Ball and Seat

Technical specification

Note: The dimension of connecting flange and butt welding terminals can be designed according to customers’ requirements.