DBB Ball Valve

Modular double block and bleed valves combine two in-line isolation valves into a single body with an additional bleed valve used to drain or vent trapped fluid between the two obturators to ensure highest level of safety in double isolation and bleed service. 

Using a double block and bleed valve versus two separate valves saves weight and space on the piping layout and ensures a significant reduction of potential leakage to the atmosphere, minimizing any hazardous risk when transferring liquids or gas. 

Several unique features are available to offer advanced technical solutions suitable to deal with aggressive and severe offshore environments. Material selection is fully customizable to meet customers project specifications.

Design Features :

Valve Design：
• based on API 6D or API 6A or API 6DSS and customer requirements
Face-To-Face：
• As per manufacture standard
Ene Connections：
• RF、RTJ as per B16.5 &B16.47；BW、 Butt Welded as per B16.25；Hub connection；6B、6BX as per API6A.
Body Design：
• Forged three-piece housing two balls
Seat Design：
• Soft or metal seated with hard facing on ball and seats、Four Self relieving seats、Four Double piston seats 、Combination seats

Features：
• Double block and bleed design (DBB)
• Secondary seals in pure Graphite
• Anti-static device
• Anti-blowout stem
• O-ring / Lip seal configuration
• Emergency sealant injection on seats and stem available
• Low fugitive emission stem packing available
• CRA overlay on all dynamic sealing areas or on all wetted parts available
• Extended bonnet for low & high temperature available
• Low pressure loss through the valve
• BTC series: extremely compact valve design as per high pressure compact ball valves
Operator：
• Manual: wrench or gear with padlocking；
• Actuated: Pneumatic/ Hydraulic/Electric.
Testing & Certifications：
• Compliance with API 6D & ISO 5208 & API 598 inspection and testing
• Compliance with API 6A inspection and testing 
• Compliance with API 6DSS Inspection and testing
• Fire safe and fire tested as per API 6FA/607 
• SIL 3 Certification as per IEC61508
• Fugitive Emission as per ISO15848
• PED 2014/68/UE 
• Available as per API 6A standard:
• Product specification levels PSL 1, 2, 3, 3G, and 4
• Performance requirement levels PR1, PR2
• Design validation as per PR2F