Double-block and bleed functions trunnion mounted ball valves
In general, J-VALVES's trunnion mounted ball valve features the front ball sealing design structure. Each seat of the ball valve can separately cut off the medium at both inlet and outlet of the valve to realize double-block functions.When the ball valve is closed, body cavity and two of the body ends can be blocked with eachother even if both the inlet and outlet are under pressure, when the medium left in the body cavity might be bled through the relief valve
Fire safe design trunnion mounted ball valves
With the valve heated in a fire application, the non-metal material parts such as seat sealing ring of PTFE, O ring for the stem, and sealing gasket for body and bonnet,might be damaged due to high temperature.J-VALVES's special design of auxiliary metal to metal or the graphite seal is provided for the trunnion ball valve to effectively prevent both internal and external leakage of the valve. As required by customers,J-VALVES's fire safe design for the trunnion ball valve meets the requirement of API 607,API 6Fa,BS 675 and JB/T 6899.
Self-reliefin the body cavity trunnion mounted ball valves
As the liquid medium left in the body cavity gasgifies due to increased temperature, the pressure in the body cavity becomes abnormally higher, when the medium itself in the cavity would propel the seat and self-relieves the pressure to ensure the safety of valve.
Trumion ball valve wihte B-sealmg design stucturele
According to some special working conditions and customers' requirement, J-VALVES has provided the trunnion mounted ball. Valve withthe double-sealing design structure, i.e. seat sealing in front of the ball and seat sealing behind the ball, thus the reliable sealing of the valve is ensured because the valve can perform normally even if one of the effective sealing designs becomes lost due to the abnormal condition.
Regarding the seat in front of the ball, the piston effect formed by the area difference between D1 and D2,plus the pre-tightened force of a spring would cause the seat in front of the ball by the pressure difference of the medium before and after the valve to touch the ball closely to form the tightness, of
Regarding the seat after the ball, the piston efffect formed by the area difference between D2 and D3,plus the pretightened force of a spring would cause the seat behind the ball to touch the ball closely to form the tightness, of which the seealing force will become bigger as the pressure difference gets higher.
Blow-out proof stem trunnion mounted ball valves
Blow-out proof structure is provided with for thestem, which is positioned by the up-end cap and screw, being guaranteed not to be blown-out by the medium even if at abnormal risen pressure in the cavity.
Anti-static design trunnion mounted ball valves
The ball of the trunnion mounted ball valve gets close contact with each other through the trunnion, adjusting cushion, and down-end cap, the passage of static electricity thus forms together with the valve, which may lead the staticelectricity caused by sparks generated by friction between the ball and seat during On and off perfc rmance to the ground to prevent the possible risk of fire or explosion.
Mounting pad provided trunnion mounted ball valves
J-VALVES company has provided for trunnion mouunted ball valve with a mounting pad for fixing the actuators, such as worm gear, pneumatic, electric, hydraulic, and pneumatic & hydraulic actuators.
The structure design of elastic sealing ring has beeen adopted for floating ball valves. This seat design features a bigger sealing pressure ratio between thering surface and the ball when medium pressure gets lower, where the contacting area is smaller. Thus, the reliable seal is ensured. When the medium pressure gets higher, the contacting area between seat ring and ball becomes bigger as the Ball sealing ring transforms elastically to undertake the bigger force pushed by the medium without any damage.
Fire safe design floating ball valves
With the valve heated in a fire application, the non--metal material parts such as seat sealing ring of PTFE, stem back seat gasket, gland packing, and ithe sealing gasket between body and bonnet might disintegrate or be damaged due to high temperature.J-VALVES's specially designed structure of auxiliary metal to metal seal is provided to effectively preventboth internal and external Ball leakage of the valve. As required by customers, J-VALVES's floating ball vallves with fire safe design can meet the requirement of API607,API 6FA,BS 6755 and JB/T 6899.
Reliable stem seal floating ball valves
The blow-out proof design has been adopted forthe stem to ensure that even if the pressure in the body cavity is risen accidently and the packing flange becomes invalid, the stem may,not be blown out by medium. The stem features the design with a back seat, being assembled from underneath. The sealing force against the backseat gets higher as the medium pressure becomes higher. So the reliable seal of the stem can be assured under variable medium pressure.
V type packing structure has been employed to efffectively transform the pushing force of the gland flange and the medium pressure into the sealing force against the stem.
Based on customers' requirement, a packing tightening design may be employed to obtain more reliable stem packing seal, which is loaded by beveling spring.
Anti-staticfeature floating ball valves
The traditional packing flange design has been imoroved to be of two piece structure, i.e., being as a packing flange plate and a follower, the latter contacts the flange plate with spherical surface. Thus, the follower remains vertical always, and is lined internallywith a PTFE bush to prevent the galling against and friction between the stem, which can also reduce the operation torque of the valve.
Wrong operation prevention
To prevent the ball valve from wrong operation, the key lock with 90 of open and close positioning pad has been provided, which can be lockable as required. At the stem head, where the lever fixes, a flat is so designed fhat the valve opens with the lever in parallelto piping, and with the lever right-angled to the piping, the valve is closed. So, it is ensured that the valve indicator of open and close can never make mistake.