Saver sub 4 1/2'' IF pin X 6 5/8'' Reg pin for OD 7 5/8'' drill pipe
The Saver sub is located between the lower end of the lower safety valve of the top drive and the upper end of the drill pipe, and is connected by thread. The Sever sub is the safety protection joint in the drill string circulation system, and is an important auxiliary drilling tool for protecting the top drive safety valve
The cemented carbide bearing design idea is adopted for casing Saver sub. The friction between bearings is used to replace the sliding friction between drill pipe joint and wellbore / casing, so as to reduce the loss of torque transmission and play a good role in protecting drill pipe.
The field installation and use of casing anti-wear joint(Saver sub) plays a supporting role on the drill pipe, thus reducing the contact area between the drill pipe and the casing when rotating, and the direct result is to protect the casing and drill pipe.