Well suspension is the wellhead sealing for a particular period of time in order to save the wellbore during the drilling process or after the end of it. Well conservation is performed for a short period of time (several months) during the process of drilling: in case of appearance in the subsurface of complicating mining-and-geological conditions, in case of well pad drilling – until the end of construction of all wells in the pad, in case of the field development – until the end of the field infrastructure development, or for a long term after the field development.

In order to save a drilled wellbore, separate well intervals formed by unstable rocks are secured for the period of conservation by a cement slurry (cement plugs) or by another binding material (for instance, by resins). These intervals are drilled through in case of well operations resuming. In case of well conservation for a long period, the X-mas tree is coated by the anticorrosion coating.