Floating Type Ball Valve
|Size Range:||1/2" - 8" (DN15 - DN200)|
|Body Style:||Full Bore, Reduced Bore|
|Temperature Range:||-196°C ~ 550°C (Note: this varies depending on the MOC)|
|Pressure Ratings:||Class 150, 300, 600|
|Body Materials:||Carbon Steel, Stainless Steel|
|Seat Materials:||PTFE, RPTFE, Sintered Carbon Fibre, Metal + Rubber Components|
|Design:||API 6D / API 608 / BS 5351|
Vahn-Tech ball valves are design with extensive safety considerations. Provision of locking devices, blow-out proof stems and prevention of misalignment of lever handles provide safe handling in the field. To ensure smooth plant operation, antistatic devices, fire safe seal design and cavity pressure relief features are provided.
1) Lever Operated Switch Indicator:
The stem of the valve is in the shape of a diploid.
When the lever is in parallel with the axis of the pipe,
the valve is in ‘ON’ position; when the lever is vertical
valve is in ‘OFF’ position.
2) Locking Device
To prevent operational mistakes, there is a provision for
mounting a locking device.
3) Blow Out Proof Stem
The lower end of the stem is designed with an integral
collar to be blowout-proof. It also functions as the
backseat for assured stem sealing.
4) Antistatic Device
Internal parts that are insulated from the valve body
by non-conductive seat and seal materials may build
up a static electric charge. To ensure electrical continuity
between the stem and the ball and body, Vahn-Tech
includes anti-static devices as an integral part of
all floating ball valves.
5) Bubble Tight Sealing
Bubble tight sealing is achieved by the use of two rigid
seats firmly secured in the valve body on either side
of the ball.
Media flow is cut off on the downstream side by
upstream pressure pushing against the ball.
6) Firesafe Design
Vahn-Tech’s floating ball valves have all been proven
to be firesafe to API 607 or API 6FA. Full metal-to-metal
contact is attained at all sealing areas after the primary
soft seals have been destroyed during a fire.
7) Live Load and Double Packing Stem Seal Feature
Vahn-Tech floating ball valves feature live-loaded, self-adjusting primary and secondary sealing. Utilizing Belleville washers, the stem seal automatically adjusts to compensate for changes in temperature and normal wear.
The primary seal is a combination of a thrust bearing and thrust washer. An adjustable stem packing creates a secondary seal between the stem and body.
8) Equalized Cavity Pressure
The pressure equalization hole at the top of the ball combined with the seat design are both engineered to maintain the pressure balance in the line and in the body cavity while the valve is in the open position.
|Floating Type Ball Valves||English|