ONE-CUTTER DRILLING BIT Russian patent published in 2012 - IPC E21B10/08 E21B12/04 

FIELD: mining.

SUBSTANCE: one-cutter drilling bit consists of housing with leg journal for support location, thread for connection to drilling column, channel for flushing fluid and one rolling cutter flexibly fixed on bearing assembly, the rolling cutter surface being provided with channels for flushing fluid and rock-destructing cutting elements. All the surface of rolling cutter provided with rock-destructing elements is covered with protector applied by the method of detonation spraying with thickness exceeding height of elements projection above rolling cutter body. All the surface of rolling cutter provided with rock-destructing elements has intermediate layer under the protector with friction factor less than that on the surface layer of rolling cutter material.

EFFECT: temporary protection against mutual damages of casing string and all the surface of drilling bit rolling cutter during its lowering to bottom-hole, qualitative application of sound protective material.

1 dwg