Research on Bottom Hole Flushing in Reverse Circulation Drilling

Abstract:

The authors consider circulation fluid in reserve circulation drilling as rigid body and establish the bottom hole flushing model based upon moment balance theory etc.. Optimal flushing conditions are presented according to the results of studying various factors affecting bottom hole flushing such as strata, structure of bit, working regulation, flow field of bottom hole, cuttinghold effect, infiltration law and so on. The results are verified in lab and on field.