Both DBB and DIB valves save space, reduce the need for costly multivalve systems, and provide zero-leakage capabilities from upstream to downstream. The valves also enable integrity check of seat seals.
DBB and DIB valves are used in applications where critical isolation is needed to ensure that leakage does not occur. Both valves can be used in a variety of applications and markets, such as LNG, petrochemical, transmission and storage, natural gas industrial processes, mainline and manifold valves in liquid pipelines, and refined products transmission lines.
Another application in which DBB and DIB valves are used is the meter calibration market. Every closed valve in the meter system must seal drop tight. Even a small leak will cause errors in the meter calibration, and the incorrect meter factor will persist until the next proving operation, costing significant sums. Choosing the correct API-verified DBB or DIB valve can help ensure correct calibration almost every time.
Cameron offers a wide range of DBB or DIB valve types and options to fit specific needs. For example, in liquid service near waterways or municipalities, double expanding gate valves with DBB capabilities, such as the Cameron WKM Pow-R-Seal double expanding gate valve, are preferred for critical isolation because they provide a tight mechanical seal simultaneously upstream and downstream, which is normally unaffected by pressure variations or vibrations.
The mechanical wedge action of a double block and bleed plug valve, such as the Cameron GENERAL Twin Seal double block and bleed plug valve, firmly compresses both the upstream and the downstream seals against the valve body, requiring no help from the line pressure to effect a positive seal. Double block and bleed plug valves, which are used often in the transmission and storage markets, provide consistent and provable zero leakage of various fluids.