Technology Application Bringing Highly Accurate Answers to Free Pipe Determination, Enabling Operational Certainty and Efficiency, Delivering Optimized Tubular Recovery
Authors: Taylor Benjamin James George , Murchie Stuart William 
Published: March 2024

For years, the need to quickly and accurately determine where drill pipe is free during a stuck pipe event has been critical – This in turn leading to a pipe backoff or cut that can either result in successful fishing and continuing to planned TD: or an unsuccessful fishing attempt and side-track. Today, accurate free pipe depth determination is equally important when pulling tubulars as part of workover and plug and abandon (P&A) operations. In both scenarios, high accuracy free-pipe determination methodology enables maximum pipe length to be cut and retrieved out of the well at the first attempt.

The clarity and reliability on pinpointing the interface between stuck and free pipe is limited when using conventional tooling, with inherent time inefficiencies due to the requirement for multiple stationary measurements. The electric line deployed technology presented here works on the principle of changes in a magnetic signature brought about by tubular manipulation. With the pipe in a neutral state, a magnetic signature is written and recorded simultaneously along the length of the tubular in the zone where the stuck point is suspected to be located. The pipe is then manipulated, either by tension, compression and or torsion before being returned to neutral. A subsequent logging pass is then completed remeasuring the original signature written. The comparison of the two passes indicates the free or stuck status of the pipe – a change in signature indicating free pipe, no change indicating stuck pipe.

Successful operations have been executed globally with the new pipe recovery technology, both in the drilling and P&A space. The range of application, the efficiency of operation and value of its clear and certain answer has been well recognized by customers. The paper will present two case studies representing a range of operations, each presenting their own unique challenges, be that completion or BHA type, well trajectory or wellbore environment. Each will demonstrate the efficiency of the operation, accuracy, and repeatability of measurement, and ultimately the certainty of the near real time answer. The answer product derived from the acquired data is delivered quickly, providing a clear indication of the free pipe without ambiguity or the need for lengthy interpretation. The new pipe recovery technology simplifies job planning, preparation and execution and has a significantly reduced wellsite footprint and ultimately delivers a reduced carbon footprint.

The technology is compatible with electric line tractor conveyance, primed for high well deviation and extended reach trajectory drilling in mind. The technology is designed for high pressure / high temperature operations as well as multiple sensor combinations for additional data acquisition per trip. The string can also be reconfigured to acquire the required data, logging in different directions to suit the operation, e.g., gravity deployment vs pump down or tractor.