Abstract

This paper describes the use of Well Tractor technology to convey services for recovery of stuck drillpipe in circumstances where conventional methods were considered economically or technically unfeasible.

In the first case, the drillpipe became stuck while running in and circulation was subsequently lost. After 100 jarring cycles were performed it was decided to attempt a fishing operation using the 2 1/8" Well Tractor enabling the retrieval of the radioactive logging source. The retrieval tool was deployed on Well Tractor, which enabled the radioactive source to be successfully recovered from the bottom hole assembly (BHA). The drillpipe was subsequently backed-off using Well Tractor to convey the explosives.

In the second case, drilling losses to the formation were experienced and it was decided to pump lost circulation material. However, during pumping the drillpipe plugged up completely. At the same time flow was recorded on the annulus side and the drilling BOP annular preventer was closed with subsequent pressure build-up below. A 2 1/8" Well Tractor was successfully run inside the DP to first gauge and subsequently punch holes in the drillpipe to open for circulation, thereby allowing pumping of heavy mud and regaining well control.