The traditional packing flange design has been improved 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.
Urgent Grease Injection Device
According to customers' requirement, the trunnion ball valves made by Baiqiang company are provided with devices for urgent grease injection, which are on both the stem and seat for the trunnion ball valves of DN> 150mm (NPS6). and in the body cavity for the valve of DN< 125mm. When the 0 ring of stem or the body seat ring is damaged due to accident, the medium leakage between body and stem can be prevented by injecting the sealing grease through the device.
Mounting Pad Provided
Baiqiang company has provided for floating ball valve with a mounting pad, through which it is easy to fix the actuators, such as worm gear, pneumatic and electric actuators.
Mounting pad provided
Baiqiang has provided for trunnion ball valve with amount-ingpad for fixing the actuators, such as worm gear, pneumatic,electric, hydraulic, and pneumatic & hydraulicacturtors.
The Bi-sealing design structure,ie. seat sealing infront of the ball and seat sealing behind the ball
According to some special working conditions and cust- omers Requirement, Baiqiang has provided the trunnion ball valve with the Bi-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 efet 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 which the sealing force will become bigger as the pressure difference gets higher. Regarding the seat after the ball, the piston efct formed by the area difference between D2 and D3 ,plus the pretig-htened force of a spring would cause the seat behind the ball to touch the ball closely to form the tightness, of which the sealing force will become bigger as the pressure difference gets higher.
Reliable Seat Seal
The structure design of elastic sealing ring has been adopted For floating ball valves. This seat design features a bigger sealing pressure ratio between the ring 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 sealing ring transforms elastically to undertake the bigger force pushed by the medium without any damage.
Fire Safe Design
With the valve heated in a fire application, the nonmetal material parts such as seat sealing ring of PTFE, stem back seat gasket, gland packing, and the sealing gasket between body and bonnet might disintegrate or be damaged due to high temperature. Baiqiang specially designed structure of auxiliary metal to metal seal is provided to effectively prevent both internal and external leakage of the valve. As required by Customers, Baiqiang floating ball valves with design can meet the require ment Of API 607, API 6FA,BS 6755 and JB/T 6899.
Blow-out Proof Stem
Blow-out proof structure is provited with for the stem, 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.
Double-block And Bleed Functions
In general, Baiqiang trunnion 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 each other 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.
The ball of the trunnion 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 static electricity caused by sparks generated by friction between the ball and seat during on and off performance to the ground to prevent the possible risk of fire or explosion.
Self-elief In The Body Cavity
As the liquid medium left in the body cavity gasifies due toinc-reased temperature, the pressure in the body cavity becomes abn-ormally higher, when the medium itself in the cavity would propel the seat and self-relieves the pressure to ensure the safety of valve.
Fire Safe Design
With the valve heated in a fire application, the nonmetal material parts such as seat sealing ring of PTFE, 0 ring for the stem, and sealing gasket for body and bonnet, might be damaged due to high temperature. Baiqiang's special design of axiliary metal to metal or the graphite seal is provited for the trunnion ball valve to effectively prevent both internal and external leakage of the valve. As required by ustomers, Baiqiang's fire safe design for the trunnion ball valve meets the requirement of API 607, API 6FA, BS 6755 and JB/T 6899.
Reliable Stem Seal
The blow-out proof design has been adopted for the 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 backseat, 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.
The traditional packing flange design has been improved to be of two piece structure, i.e., being as a gland flange and gland, the latter contacts the gland flange with spherical surface. Thus, the gland remains vertical always, and is lined internally with a PTFE bush to prevent the galling against and friction between the stem,which can also reduce the operation torque of the valve. Sign may be employed to obtain more relible stem packing seal, which is loaded by belling spring. Based on customers' requirement, a packing tightening de
V type packing structure has been employed to effectively trans form the pushing force of the gland flange and the medium pressure into the sealing force against the stem.