Double Piston Effect

The seat rings may be modified to perform the DOUBLE PISTON EFFECT on customer's requirement. In this case, the pressure acting on both the external and internal side of the seat rings push them against the ball. Therefore each seat grants the required tightness. This design feature allowed an additional sealing function, but to release the possible over pressure developed in the body cavity it is necessary to use a safety relief valve on the body.

Stem Sealing

The perfect sealing is granted by the use, as a standard feature, of the two O-rings and a graphite gasket retained by stem cover. The graphite gasket can be changed with the valve in line and the ball in any position, but this is done after having release pressure between upper O-ring and graphite gasket. The stem seals can be replaced with the valve under pressure and the ball in fully closed or fully opened position and the pressure in the body cavity has been completely released.

Floating Seat with Fire Safe Design

Independent floating seat rings assure the required bi-directional tightness at every pressure in the pressure range of the valve. The seat rings are spring loaded to greant the required tightness even at very low pressure. If the seats are destroyed by abnormal heating in an emergency such as a fire etc. the seat rings will move to the ball by compression on springs and fluid, then temporary sealing surface is provided by metal to metal contact between the ball and seat rings (metal seal surface are mechanized for the seat rings), and the amount of leakage will be minimized. This conformes to API607 fire safe requirements.

Single Piston Effect with Pressure Self-Relief

Foe the RAM Valve USA standard trunnion mounted ball valve, each seat ring performs the SINGLE PISTON EFFECT. Under such circumstance the pressure acting on the seat rings force pushing the seat to the ball. When the pressure is s applied on the external side of the seat rings the required tightness is granted.

Should the pressure of the fluid inside the valve body exceeds the line pressure, the force which acts on the seat rings by the cavity fluid does eliminate the spring elasticity and the fluid so that make the eat clearance between the seats and ball. Upon such clearance, seats provide automatic pressure relief from the body cavity to the pipeline.

Emergency Seal Recovery

When leakage occurs at the seat and gland due to damage, leaks from the seal can be temporarily stopped by injection of sealant into the secondary seal system. The sealing action of one O-ring or NPT only and one ball inside is the standard feature of the emergency sealant, but with two O-rings and two balls inside available also on customer's requirement.

Actuation

RAM Company USA trunnion mounted ball valves are designed to be operated by manual operators such as wrench or gear operator, the use of wrench is limited to bore size and pressure class equal or smaller than:

6" - CLASS 150LB
6" - CLASS 300LB
4" - CLASS 400LB
4" - CLASS 600 LB
2" - CLASS 900LB
2" - CLASS 1500LB

Body Sealing

Two O-rings and graphite gaskets placed at joins of the body components guarantee zero leakage.

For valves which operated by wrench can also be changed to ear operator on customer's requirement.

Actuators of valves can be supplies with Electric actuator, Pneumatic actuators and Gas over oil actuators. Gear operators can be easily removed in service and replaced by actuator.