SureLOC

Electronically controlled cable release device

Offshore rig in stormy seas.

Reliable cable release under the most challenging tool-sticking situations

Mechanical weakpoints are conventionally used in operations with high cable tension to safely separate the cable from a stuck tool downhole. Different-strength weakpoints are used to ensure breakage before exceeding the cable safe working load. Under certain conditions, the surface-applied tension is too high or cannot be effectively transmitted to break the weakpoint. The result is a lengthy cable-attached cut-and-thread fishing operation or in, the worst-case scenario, a broken cable left in the well on top of the fish.
The higher-rated release spring and prepackaged release bobbin assembly of the SureLOC device deliver superior efficiency and consistent performance.
The higher-rated release spring and prepackaged release bobbin assembly of the SureLOC device deliver superior efficiency and consistent performance.
SureLOC cable release device.

To overcome the operational limitations of mechanical weakpoints and previous-generation electronically controlled release devices (ECRDs), Schlumberger developed the SureLOC 12000 and 8000 cable release devices. Installed in the wireline logging head, the SureLOC 12000 device is activated by a software command and electrical power to reliably release the cable under a wide range of downhole conditions. Combined with TuffLINE torque-balanced composite wireline cable, the electronic release reliability for the SureLOC device exceeds 97%.

SureLOC 12000 and 8000 release devices can be complemented with inline addressable electronically controlled release devices positioned strategically along the toolstring.