DBB Plug Valve

A DBB plug valve (Double Block and Bleed plug valve, or dual-expanding plug valve) is a specialized isolation valve featuring two independent seating surfaces on a single plug mechanism with an intermediate body bleed cavity, designed to provide verifiable double isolation and bleeding from a single valve body. When fully closed, both upstream and downstream seats seal simultaneously, allowing operators to vent or drain the internal cavity via the bleed port to verify zero-leakage isolation without interrupting process flow. Conforming to standards like API 6D, API 599, and ASME B16.34, these high-integrity safety valves are primary specifications in petroleum custody transfer metering skids, aviation fuel storage terminals, and multi-product manifolds, allowing pipeline operators to prevent product cross-contamination by importing certified DBB plug valves directly from specialized manufacturers in China via our advanced B2B commercial platform.