EP 0237359 A3 19881123 - ROTARY DRAG BITS
Title (en)
ROTARY DRAG BITS
Publication
Application
Priority
US 83943486 A 19860313
Abstract (en)
[origin: EP0237359A2] 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)
Citation (search report)
- [X] US 4553615 A 19851119 - GRAINGER ALFRED J [GB]
- [YP] GB 2167107 A 19860521 - BROWN KEITH MALCOLM
- [Y] EP 0079243 A1 19830518 - SUMITOMO ELECTRIC INDUSTRIES [JP]
- [A] US 4448269 A 19840515 - ISHIKAWA YASUAKI [JP], et al
- [A] US 1533286 A 19250414 - WICKERSHAM HARRY P
- [A] US 3830321 A 19740820 - MC KENRY R, et al
- [AD] US 4253533 A 19810303 - BAKER III WILLIAM
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