EP 0237359 A2 19870916 - Rotary drag bits.
Title (en)
Rotary drag bits.
Title (de)
Fräsdrehbohrmeissel.
Title (fr)
Trépan rotatif du type racleur.
Publication
Application
Priority
US 83943486 A 19860313
Abstract (en)
A rotary drag bit (11) has cutters (19) rotatably mounted to fixtures (21) with journals. The cutters (19) are constantly forced to rotate or precess by the interaction between the earth formation and the cutter (19). The cutters (19) are fixed in skewed or offset positions on a cutting face (17) of a rotary drill bit head (11). These cutters (19) act as drag or shear cutters when they are operated in an earth formation.
IPC 1-7
IPC 8 full level
E21B 10/50 (2006.01); E21B 10/52 (2006.01); E21B 10/56 (2006.01); E21B 10/567 (2006.01); E21B 10/62 (2006.01)
CPC (source: EP US)
E21B 10/50 (2013.01 - EP); E21B 10/52 (2013.01 - EP); E21B 10/5673 (2013.01 - EP US); E21B 10/62 (2013.01 - EP)
Designated contracting state (EPC)
BE DE FR GB IT NL
DOCDB simple family (publication)
EP 0237359 A2 19870916; EP 0237359 A3 19881123; AU 590826 B2 19891116; AU 6998587 A 19870917; BR 8701601 A 19880112; CA 1260923 A 19890926; MX 161103 A 19900731; NO 871037 D0 19870313; NO 871037 L 19870914
DOCDB simple family (application)
EP 87302180 A 19870313; AU 6998587 A 19870313; BR 8701601 A 19870313; CA 531987 A 19870313; MX 558087 A 19870313; NO 871037 A 19870313