18 July 2017
A wellbore that has been unintentionally drilled in a direction other than vertical. It usually occurs where there is a section of alternating hard and soft […]
18 July 2017
An assembly of sheaves mounted on beams at the top of the derrick and over which the drilling line is reeved. See block, reeve, sheave.
18 July 2017
A rig that utilizes a hydraulically powered hoisting system with long stroke cylinders for pushing a sheave cluster and traveling assembly vertically. These cylinders and sheave […]
25 July 2017
In areas where three 8-hour tours are worked, the shift of duty on a drilling rig that starts at or about daylight. Compare evening tour and […]