EP 0322347 A1 19890628 - Drag bit with nozzles for drilling plastic formations.
Title (en)
Drag bit with nozzles for drilling plastic formations.
Title (de)
Fräsmeissel mit Düsen für das Bohren von plastischen Formationen.
Title (fr)
Trépan racleur avec buses pour le forage de formations plastiques.
Publication
Application
Priority
US 10679387 A 19871013
Abstract (en)
A bit and method for cutting plastic and sticky rock formations, which tend to cause bit balling, is provided by a drag bit (10) having a cutting face formed of a plurality of generally radially extending open arched blades (20). Each arched blade (20) is provided with a cutting face and defines a cavity (24) beneath the arch to the bit body. In a preferred embodiment, the cutting elements on the arched blade are a plurality of synthetic polycrystalline diamonds (22) which are cut, sized and shaped to conformally fit with each other so as to present a substantially diamond-only surface as a cutting surface of the bit. Hydraulic nozzles (38) are defined in the bit body beneath and azimuthally behind the arches formed by each blade. The nozzles direct hydraulic flow across the cavity under the arch and across each portion of the cutting face on the arch. As a result, when cutting, substantially only a diamond surface is provided for shearing the rock formation or contacting with velocity any portion of the plastic rock formation. Once the rock chip is exuded upwardly across the diamond face of the cutter, it is subjected to a directed hydraulic flow which peels the chip from the diamond face and transports it into the open cavity defined underneath the arched blade. The cavities under the arched blade form an open toroidal space around the bit and freely communicate with a plurality of large open waterways and junk slots. Large plastic fragments may then be cut, peeled from the face of the diamond cutters, and flushed through the waterways up the junk slots.
IPC 1-7
IPC 8 full level
E21B 10/56 (2006.01); E21B 10/567 (2006.01); E21B 10/60 (2006.01)
CPC (source: EP US)
E21B 10/5671 (2020.05 - EP); E21B 10/5673 (2013.01 - EP US); E21B 10/602 (2013.01 - EP US)
Citation (search report)
- [X] EP 0233737 A2 19870826 - REED TOOL CO [US]
- [Y] FR 2391350 A1 19781215 - SHELL INT RESEARCH [NL]
- [A] BE 903059 A 19860213 - DIAMANT BOART SA
- [AD] GB 2181173 A 19870415 - NL PETROLEUM PROD
- [A] DE 1169386 B 19640506 - EUROP DE TURBOFORAGE SOC
Designated contracting state (EPC)
AT BE CH DE ES FR GB GR IT LI LU NL SE
DOCDB simple family (publication)
EP 0322347 A1 19890628; EP 0322347 B1 19941130; CA 1302393 C 19920602; DE 3852286 D1 19950112; DE 3852286 T2 19950622
DOCDB simple family (application)
EP 88710035 A 19881012; CA 579887 A 19881012; DE 3852286 T 19881012