EP 0259872 A2 19880316 - Large compact rotary drill bit utilizing directed hydraulics for each cutter.
Title (en)
Large compact rotary drill bit utilizing directed hydraulics for each cutter.
Title (de)
Drehbohrmeissel mit grossen Schneidelementen und einem Flüssigkeitsstrahl für jedes Schneidelement.
Title (fr)
Trépan de forage rotatif avec éléments de coupe de grande dimension utilisant un jet de fluide dirigé pour chaque élément.
Publication
Application
Priority
US 90616986 A 19860911
Abstract (en)
An improved rotating drag bit for cutting plastic, sticky, water reactive and shale formations is devised by providing a plurality of large diamond cutters having a circular cutting face in excess of three quater inch in diameter. Each large cutter is provided with at least one hydraulic nozzle which in turn provides a directed hydraulic flow at the corresponding cutter face. The directed hydraulic flow is positioned to apply a force to the chip which tends to peel the chip away from the cutter face. In addition, the hydraulic flow is positioned with respect to the chip so as to apply an off-center torque to the chip which is used to peel the chip away from the cutter face and toward the gage of the bit. In particular, the nozzle defines a jet which is characterized by a direction and velocity of hydraulic fluid determined by the jet characteristics. The core is generally symmetric about its longitudinal axis and has a length along the longitudinal axis and width perpendicular thereto. The point of the jet most distant from the nozzle defines an impact point of the jet against the chip and cutter face. The longitudinal axis of the jet is chosen so that at least a portion of the jet lies between the cutter face and the chip as it is being peeled from the cutter. Hydraulic removal of the chips is further facilitated by a plurality of junk slots having a contoured compound surface. The junk slot is characterized by having at least two distinct cross-sectional profiles, namely an asymmetric profile at its lower portion nearest the bit face and a symmetric profile along its upper portion. The asymmetric and symmetric profiles are connected by a surface providing a smooth hydrodynamic transition.
IPC 1-7
IPC 8 full level
E21B 10/46 (2006.01); 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 US); E21B 10/60 (2013.01 - EP)
Designated contracting state (EPC)
BE DE FR GB NL
DOCDB simple family (publication)
EP 0452999 A2 19911023; EP 0452999 A3 19920311; CA 1295321 C 19920204; DE 3781226 D1 19920924; DE 3781226 T2 19930325; EP 0259872 A2 19880316; EP 0259872 A3 19891025; EP 0259872 B1 19920819; JP S63134782 A 19880607; NO 873803 D0 19870911; NO 873803 L 19880314
DOCDB simple family (application)
EP 91111602 A 19870910; CA 546521 A 19870910; DE 3781226 T 19870910; EP 87113231 A 19870910; JP 21806587 A 19870902; NO 873803 A 19870911