Calculations Of Drill Pipes Collapse Pressure
Definition Of Drill Pipe Collapse Pressure

The Drill Pipe may at certain times be subjected to external pressure which is higher than the internal pressure. This condition usually occurs during drill stem testing and may collapse the drill pipe.    

The  differential  pressure  (external  pressure  minus  internal pressure) required to produce collapse is calculated for various sizes and grades of new and used drill pipe and is presented in API RP7G Tables (3), (5) and (7). 
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