
Double Block and Bleed Dual Expanding Plug Valve
Double Block and Bleed
Dual expanding plug valves have a double block and bleed function up and downstream. Normally this can only be achieved by using two (2) valves and a spool piece with a drain valve. The use of a Double Block and Bleed Valve will save cost, space and maintenance for a long period.
Friction Free
An important aspect of a valve is the sealing mechanism. Almost all valves, like standard Ball, Gate and Butterfly valves have their sealing mechanism based upon shear force, friction and tearing. The sealing mechanism is based upon a radial movement only. The sealing is not liable to shear, friction or tearing. This means no abrasion on the seal and compared to other types of valves, results in an exceptional long lifetime.
In-Line Maintenance and Service
As the dual expanding valve is designed for easy and low cost maintenance, stem packings can be adjusted while the valve is in service. All valves are executed with a back seat. Bottom and top entry is possible while the valve is inline. No special tools are required.
Non-Slam
The self-locking operate mechanism on all dual expanding plug valves provides that the closing member (plug) cannot rotate due to line forces. Therefore there is no danger of line slam, shock or injury to personnel.
Fire Safe
The plug valves have been Fire safe tested by independent laboratories and have passed the tests.
STANDARD MATERIALS OF CONSTRUCTION |
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Body: | Cast Carbon Steel ASTM A-216 WCC Chrome Plated Seat Area |
Bonnet: | Cast Carbon Steel ASTM A-216 WCC |
Lower Plate: | Cast Carbon Steel ASTM A-216 WCC |
Solid Plug: | Cast Carbon Steel ASTM A-216 WCC Electroless Nickel Plated |
Slip/Seal: | Cast Ductile Iron 80-55-06/Viton |
Trunnion Bushings: | Type 2 NI-Resist |
O-Rings: | Viton |
Packing Gland: | ASTM A-487 CA6NM |
Chevron Packing: | Grafoil /V-Rings |
Studs: | ASTM 193 B7 |
Nuts: | ASTM 194 2H |
Bleed System: | Differential Thermal Relief / Manual Body Bleed |
TRIM SELECTION |
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Fluoro Elastomers Slip Seal Materials | ||||
VIT | Viton | Standard Material | ||
V90 | Viton 90 Durometer | Standard HI∆P | ||
VGF | Viton GF | Viton with Enhanced Chemical Resistance | ||
VTF | Fiber Reinforced Viton | Optional HI∆P | ||
Nitrile Elastomers Slip Seal Materials | ||||
NIT | Nitrile | |||
HNBR | Hydrogenated Nitrile | Low Temp Nitrile | ||
STS | Modifi ed Nitrile | Reformulated Gasoline Seal Material | ||
Specialty Slip Seal Materials | ||||
ECH | Epichlorohydrin | Good Low Temp Material | ||
EPDM | Ethylenepropylene | Ammonia but not Hydrocarbon |