Method for cleaning and sealing a well borehole portion for formation evaluation

摘要

A borehole wall cleaning apparatus and method for obtaining an improved seal between a fluid sampling device and a portion of the borehole wall. Clean drilling fluid is pumped into a drilling tool using a mud pump. A fluid diverter in the tool diverts all or part of the clean drilling fluid through a port to clear a portion of a borehole wall. A sealing pad is moved against the clean portion. A sampling port is exposed to the sealed portion for sampling and/or testing fluid from the formation.