SINGLE BLOCK VALVE-MB1 SERIES

Single block and bleed valves are used to achieve positive isolation when performing maintenance activities in a live process plant. Typically one block valve and a bleed valve are Stockists & Supplier as a single assembly and this single block and bleed valve manifold can be readily installed for isolation purpose. There is a lot of misunderstanding surrounding the term ingle Block Valve-MB1 Series as used to describe valve functionality. It seems almost every valve buyer and Stockists & Supplier has a different idea of what the term means for valve selection, which can result in the wrong specifications or valve type. Some of this confusion in the oil and gas industry stems from the fact that there are two credible sources that define the term differently.

Single block and bleed valves are usually used for non-critical process service, such as low pressure system or non toxic, non hydrocarbon, non-hazardous process fluids. For critical service, double block and bleed valve assemblies must be used. To perform positive isolation while performing maintenance, repair or shutdown activities, single block and bleed can be used in the following way. The block valve is closed first. The shutdown side of the block and bleed assembly is then drained/vented/purged to make ready for maintenance.