Therefore,the optimized design of series and standardization of drill pipe slips is carried out in two aspects: (1) if the structure is allowed,try to enlarge the contact length and area between slips and drill pipe for improving the bearing capacity of slips and not damaging the drill pipe; (2) improve the assembling structure of slip body and slip element to ensure enough slip streng.

Analysis of the slip of a packer using the finite element method;

The slips in the packer is for supporting packer and for locking rubber after anchoring.

It is very important for the designs of well casing strings, especially for thos e of deep wells and super deep wells to analyze the load bearing capacity of tub es inside slips.

Analysis on the load bearing capacity of tubes inside slips is necessary for the design of casing string in oil well, especially for that of deep well and ultradeep well.

Analysis on the load bearing capacity of tubes inside slips is very important for the design of well casing string, especially for that of deep well and super deep well.

In this paper,an automated tripping system for downhole pipe string was put forward,which includes the tractor hoist,the derrick,the hydraulic tongs,the movable casing elevator,the fixing spider,the vertical pipe rack and the controlling system.

Application of pneumatic clip for oil drilling rig;