Safety of casing-shoe test and casing-shoe integrity after testing

Increased injection volume during a casing-shoe test is needed to gather data, but it increases the possibility of lost circulation or reduced casing-shoe strength after testing. These hazards often encour7 age drilling engineers to halt casing-shoe tests prematurely just to confirm the casing-shoe strength. This paper addresses drilling-engineering concerns regarding lost circulation during a casing-shoe test, the extent of fracture propagation, the amount of data obtainable as a function of the drilling-fluid volume injected, and the casing-shoe integrity expected after testing. Laboratory data and a numerical model are used to illustrate phenomena that occur during casing-shoe tests. Analysis of the data yields guidelines for safe casing-shoe tests.