Deployment challenges for long, heavy perforating guns in a highly deviated well

A North Sea operator needed to perforate a long interval in a highly deviated (>63°) well. Although the efficiency and versatility of wireline deployment was preferred, conventional wireline operations would not be capable of conveying such a long string in one run—367 ft of guns was planned. The weight of the long gun string, at about 6,000 lbf, would also generate significant shock when setting the monobore anchor with automatic release (MAXR), which could damage the capability of conventional cable to effect weakpoint release by either pull or electrical command, in turn greatly increasing the risk profile for the perforating operation. However, the alternative approach of deployment on coiled tubing was considerably more expensive for the operator.

Incorporating the WIReD devices in the MaxPull 26000 system would mitigate the risks posed by the heavy perforating string and the shock it would generate when setting the MAXR—even if communication via the cable were lost or damage affected pulling capability. The full pulling capability of the TuffLINE torque-balanced composite wireline cable could be employed by the MaxPull 26000 system for efficient gun deployment at the predicted surface tension of 22,620 lbf at total depth of 19,732-ft MD.

Savings of USD 1.3 million from single-run wireline deployment

Two WIReD release devices were incorporated in the MaxPull 26000 system to mitigate the twofold risk stemming from sustaining the high shock and maintaining the ability to disconnect and retrieve the cable even in the event of cable damage.

Successfully deploying the long, heavy perforating gun string on wireline with the MaxPull 26000 system instead of resorting to coiled tubing generated more than USD 1.3 million in cost savings for the operator. The operational risk was significantly reduced across multiple contingency scenarios by the inclusion of the WIReD release devices at critical points.