Definition - What does Snubbing mean?
Snubbing is a process of performing heavy well intervention operations in a well by inserting tools when the back pressure or kick is being examined. It can be done in an existing well or in new well without the removal of the blowout preventer (Christmas tree) from the wellhead. Snubbing can only be carried out in a live well, i.e., when a well is not killed and is still under pressure.
Petropedia explains Snubbing
Snubbing is only performed when a heavy back pressure or kick is examined from a live well (producing well). In this process, the bottom hole assembly (BHA) on a drill string is run down into the wellbore with the help of a hydraulic workover rig, without removing the blowout preventer (BOP). Since the BOP’s are not removed while carrying out this operation, this introduces pressure in the wellbore on the cross sectional area of the tubular which thereby exerts sufficient force on the drill string to overcome the wellbore pressure; thus the drill string can be pushed or snubbed back into the wellbore.
To perform Snubbing operations, rigging organizations have small Snubbing units as well as large Snubbing units. For example, many Canadian oilfield companies have small Snubbing units that can be broken and rigged up in the matter of a few hours.