Measurement-While-Drilling (MWD) development for air drilling

摘要

When downhole contact between the BHA and formation was optimum, as it was during rotation, high signal levels were experienced. Survey data acquired at the connections, when the BHA was totally at rest, is excellent. GEC intends modifying the system to optimize operations consistent with these disparate factors. A Mean-Time-To-Failure (MTTF) of 89.9 hours appears reasonable from the data. It is not possible to infer an MTBF figure from this test. It is quite obvious, however, that the system reliability performance has been significantly improved since FT {number_sign}5 was performed almost two years earlier. Based on the above results, GEC concludes that it is certainly feasible to attain 100 hours MTBF, for the Model 27, in any and all situations, and hence to provide a reliable MWD for air-drilling.