DID YOU KNOW Max Overpull

Your Maximum Overpull can be well below the tension limit of your drill pipe? That shallow doglegs can greatly reduce your maximum overpull?
What is happening: What your drill pipe feels during an overpull even is not just tension – but is a combined load of tension, torque (if present), and bending. Shallow doglegs can cause high side forces and bending stresses!
If taking only the drill pipe published tension limit, the example below would think that an overpull of 100 kips (at the bit) is no problem – however, the shallow doglegs and associated bending stresses show that the overpull limit is not felt at surface – but rather at ~1,100’!

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