Abstract:
During drilling different layers with different lithology and mechanical properties
where the drilling process encounters many wellbore instability problems specifically
in weak formations which required different mud weight and rheological properties to
be used, the easier method is to separate between this layers by using casing, but by
this way drilling will end up using many casings in single wellbore which in turn
appears to be not economic solutions, which lead to search for an efficient and
economic solution for that problems and the Loss prevention materials (LPM) are
considered one of the best ways to protect weak formations due to their economic
quality compared to other methods , and to apply the LPM should know the wellbore
instability problems, by application of geomecanical Earth model that used to give
the mechanical properties (rock strength, horizontal stress , wellbore instability
analysis ) that used as effective tool to know and detect all the risks that can be faced,
which helps to determine the suitable mud weight without cause a problems for any
zone, to provide the data that required for create a Loss prevention materials Design
to protect the weak formation by determined the (Fracture width and particle size
distribution) to select the loss preventive materials(LPM) concentration for each weak
zone to protect it and avoid the damage by the economic way .
