Tool sticking conundrum

Tool sticking is an all too common occurrence in the HPHT reservoirs of the Gulf of Thailand. Operators were resorting to redundancy in their release systems by pairing a conventional ECRD, which did not perform reliably, with a mechanical weakpoint. Not only did the use of a mechanical weakpoint limit cable pulling capability but conversely the downhole stress required to part the weakpoint in the deep boreholes could exceed the maximum stress applicable at surface. Applying excessive tension at surface could break the logging cable there, resulting in a challenging fishing operation involving a long length of tangled cable in the borehole.

Reliable release

The SureLOC electronically controlled cable release device overcomes the operational limitations of mechanical weakpoints and previous-generation ECRDs to reliably perform under a wide range of downhole conditions.

Installed in the wireline logging head, the SureLOC device allows full conveyance pull capability for stick prevention and mitigation as needed. Activation by a software command and electrical power enables releasing the cable, even in situations with excessive surface-applied tension or ineffective tension transmission along the cable. In combination with TuffLINE torque-balanced composite wireline cable, the SureLOC release device performs with more than 97% release reliability.

Less fishing, more logging

Deployment of the SureLOC 12000 release device has provided increased reliability, greater pulling capability at surface, and the ability to release under tool head tension at 1,000 lbf. As a result, wireline fishing operations have been reduced to greatly improve logging efficiency. The operators can run longer, heavier toolstring combinations to reduce the number of well descents and acquire full sets of logging data.