Published December 2018

Application of bicentric milling cutters and centralizing tools in emergency wells repair

D.A. Iskenderov

Y.A. Ibrahimov

The casing string consists of well tubing of one type and size, but various wall thickness throughout the length; in a few cases, the thickness may be higher in upper part, and comparatively less in the lower part. Internal diameter of well tubing reduces in some methods of casing tightness recovery. Conducting emergency works in the wells stopped during operation by milling cutting of emergency heads or their annular space as a desperate measure with the milling cutters of minor diameter serves a reason for a larger deformation of emergency heads to the extent of breakoff. It leads to the complication in the well, ultimately prolonging the time spent on repairs. It is noted that in mentioned cases the application of offered bicentric milling cutters and centralizing tools in emergency wells’ repair is of immediate interest, as well as the paper presents the data on structure properties and their advantages in corresponding well conditions.