A floating ball valve is a valve with its ball
floating (not fixed by a trunnion) inside the valve body, it drifts
toward to the downstream side and tightly pushes against the seat under
the medium pressure to ensure sealing reliability. The floating ball
valve has simple structure, good sealing performance but the seat
material is required to withstand the workload since the sealing
pressure is bared by the seat ring. Due to unavailability of high
performance seat material, floating ball valve is mainly used in middle
or low pressure application.
Design FeaturesReliable Seat Seal
The structure design of double-beveled
sealing ring has been adopted to reduce the friction between the ball
and the sealing ring to achieve lower operation torque. When
the medium pressure is low, the ball has smaller contacting surface
with sealing ring, which introduces higher sealing pressure to ensure
the sealing reliability. When the medium pressure gets higher, the
contacting area between ball and sealing ring increases accordingly.
Larger contact area reduces the sealing pressure to avoid the
deformation of sealing ring.

Fire Safe Design
In case of fire, non-fireproof material for
packing and seat will be burnt-out and considerable medium leakage may
possibly cause fire spread. CRV adopted metal to metal seal as
auxiliary structure to prevent medium leakage in case of fire as shown
in figures. The fire safe design confirms to the requirements of
API607, API 6FA and BS 6755.
