Borehole instability mechanism and Countermeasures Part-III

 

First, determine a reasonable drilling fluid density, based on the collapse pressure and fracture pressure to stress three pressure profile, in order to maintain a stable state formation in mechanics; then according to the formation of mineral components, fabric characteristics, has been drilling conditions, laboratory test results etc. to determinate drilling fluid type, formulation and corresponding engineering measures compatible with the collapse formation properties. Factors preferred type of drilling fluid, formulation, preferably with the naked eye performance of drilling time, casing program, drilling parameters, technology and other measures must be combined with comprehensive consideration.

To be continued