Case Histories – Casing Failures
- Signa has been represented both plaintiffs and defendants for numerous recent failures of P-110 grade casing and connections. Some were due to manufacturing issues; however, our experts have shown that a high number of failures can be traced back to errors in hole design and operational misuse.
- Signa proved that an operator did not perform a formal casing design. The operator simply used a cookie-cutter casing design from an offset well without reevaluation. Through research and testimony, Signa proved P-110 was the incorrect grade for the downhole environment.
- Our team of experts showed improper casing-running resulted in excessive stresses. In this case, the stresses caused cold-working of the steel, which led to premature failure. The operator was responsible for the excessive operational issues that damaged the
- A Signa expert witness testified that P-110 casing is highly susceptible to acid gases such as H2S and CO2. In this case, the operator improperly used high-strength casing in the sour gas environment. Using graphics and written verbiage, Signa explained the limited P-110 envelope in the presence of either CO2 or H2S.
- Signa has shown (in reports and testimony) that P-110 casing and connection failures resulted from operational errors rather than manufacturing oversights, including:
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- Downhole pressure, temperature, and chemical environment
- Tensile, compression and collapse loads, in conjunction with buckling, impact or vibration
- Operational stress condition at the time of failure
- Premature connection or seal failure due to improperly applied torque
- Mud chemistry, such as free hydrogen contribution to hydrogen embrittlement or stress corrosion cracking
- Coupling failures from improper application of thread profile or non-optimal makeup
- Frac stimulation failure due to improperly specified pipe or high-risk wellbore geometry
- Casing wear during operations
- Improper handling (loading, trucking, unloading) between the mill and well site resulting in premature failure
