Ball valve double block

Double block and bleed valves replace existing traditional techniques employed by pipeline engineers to generate a double block and bleed configuration in the pipeline. Conventionally, in order to achieve a double block and bleed system, engineers would install two standard isolation valves and a separate facility for bleeding the cavity in between.

Space is usually at a premium in the refinery environment, and this approach requires an additional valve unit to be installed as well as a “T”-junction to allow the cavity to be bled to more than double the space required compared with a single valve system. This increase in size can often make the installation unfeasible, especially where multiple valves along the line are to be upgraded.