Collapsed Casing Risks, Indications & Mitigation
Collapsed Casing / Tubing Stuck Pipe

Casing collapses either if pressure conditions exceed its original rated collapse pressure or the original collapse pressure rating of the casing is no longer valid due to casing wear and/or corrosion. Casing wear due to friction or corrosion decreases the effective collapse pressure rating of the casing, through decreased wall thickness. Collapse is often discovered when the Bottom Hole Assembly BHA is run into the hole and hangs up inside the casing.
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