Confirm latching before pulling memory gauges

A slickline crew needed to pull memory gauges from a depth of 2,617 m, where the wellbore deviation was 60°. Using surface tension alone, it was not possible to determine if the gauges had been latched. Multiple attempts were made to determine if there was tension increase indicative of a latch. During repeated attempts to jar down and latch, the pulling tool pin was sheared, and the string had to POOH to be redressed and run again.

Run lightweight digital slickline cable

The crew chose to use Schlumberger LIVE digital slickline services. Compared with a standard slickline cable system, LIVE digital slickline services have an integral coating that allows two-way telemetry between a surface acquisition system and slickline-conveyed downhole devices. Cable tension, shock, well deviation, and tool movement are all measured by a downhole basic measurement cartridge and monitored in real time at surface. Accurate and precise depth correlation is available through gamma ray and casing collar locator measurements.

Save runs and prevent potential damage

After several attempts to latch the memory gauges, no weight gain was observed at surface. The operator did not want to POOH with the reverse gradient because of doubt that the gauges had been successfully latched. Data from the downhole tension sensor, however, indicated a 25-lbf gain; therefore, a reverse gradient was performed and, as the downhole tension sensor had indicated, the gauges had been successfully latched, allowing for recovery. This operation saved at least one run and prevented potential damage to the gauges from repeated jarring down in attempts to latch.