We Know PVF a Blog by MRC Global
  • 2017 Audit Lessons Learned
  • How to Size an Actuator - Part 4
  • How to Size an Actuator - Part 3

Defining Double Block and Bleed

By Greg Peterson, Executive Director - Midstream/Upstream Valves & Automation, MRC Global
April 11, 2017 Tags: Valves, Double Block and Bleed, DBB, DIB, Double Isolation and Bleed

A common question we hear from many of MRC Global’s customers concerns the definition of a double block-and-bleed valve. There is confusion because there are many interpretations of the term double block-and-bleed (DBB) when describing valve functionality. It seems that almost every end user and manufacturer has a different idea of what the term means for valve selection, which can result in the wrong specifications or valve type.

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Rethinking the Conventional Options - When a Triple Offset Butterfly Valve is a Better Solution

By Ralph Chaney, Senior Director - Downstream Valves & Automation, Supply Chain Management
February 24, 2016 Tags: Valves, Triple Offset Butterfly Valve, Block Valve, Gate Valve

For many years, the gate valve has been the “go to” valve for isolation, simplicity and availability for process containment. If an application required a block valve, the gate valve was selected 90% of the time. For extreme applications, when the process conditions exceeded the gate valve’s parameters, a ball valve was used. However, we are now seeing that, in certain applications, a triple offset butterfly valve could be a better solution.

The triple offset valve offers many advantages like ease of operation, commercial availability with larger sizes even in alloy materials, and a smaller envelope size and weight.

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