Overshot CSK-146
Robust, reliable, safe, these are the qualities of the Overshot CSK-146 from TECSO, S.A.
To extract the inner tube assembly, we need an Overshot, which is thrown through the inside of the rods to unlock it.
Working method:
After the drilling operation is complete, we must suspend the drill string to allow the core lifter spring to catch and break the core.
In this position, and as long as we have an adequate water level, we must lower the Overshot to the bottom of the drill string.
The overshot will sit on top of the inner head and due to its own weight, it will unlock the latches and the head will be free so we can extract the
overshot assembly plus the inner tube assembly.
In case of water losses and no water column in our string, we must use the “dry hole device”, an accessory that complements the overshot and
must be preloaded on the surface, with the help of the assembly tool, to allow the release of the inner tube and its subsequent lifting.
