ClassID:

135381

E21B21/012 - CPC Classification

Classification description:

Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor; Arrangements for handling drilling fluids or cuttings outside the borehole, e.g. mud boxes; Dust eliminating or dust removing while drilling using exhaust air from the drilling motor for blowing off the dust at the borehole entrance

Recent Application in this class: