Working Principle of DBB Ball Valves (Double Block & Bleed)
The key to the dual shut-off and bleed function lies in the operation of two sealing discs mounted on the plug. The valve is equipped with an automatic bleed-off device (optional), which prevents abnormal pressure buildup in the valve cavity after full closure and verifies the valve's sealing performance. The position indicator synchronizes with the valve's open/close status, providing accurate visual confirmation.
Structural Design
DBB double-block ball valves are available in full-bore and reduced-bore configurations.
Full-bore valves feature a flow path diameter matching the pipeline, minimizing flow resistance and facilitating pipeline cleaning.
Reduced-bore valves offer lower flow resistance than same-sized gate valves while being 30% lighter, significantly reducing production costs and pricing, making them widely adopted in industrial applications.
Specification
Size Range: 2"-24" (DN50-DN600)
Pressure Rating: ASME CLASS 150-2500 (PN16-PN420)
Body Material: Carbon steel, Stainless steel, Alloy steel, Duplex stainless steel, etc.
End Connection: FLAN (RF, RTJ), etc.
Operation: Manual, Pneumatic, Electric, Hydraulic, etc.
Fire Safe Design: Yes
Delivery, Payment and Service
Payment Terms: Normally 30% down payment before production, 70% balance before delivery.
Warranty: 12 months after installation or 18 months after shipment whichever comes first.
Delivery time: Subject to stock availability at placement or order and factory workloads.
Delivery method: By Express, or by air, or by sea, as your request.
Delivery port: Shanghai or as your request.
