EP 0563561 B1 19970423 - Superimposing drilling bit
Title (en)
Superimposing drilling bit
Title (de)
Bohrkrone zum Überlagerungsbohren
Title (fr)
Trépan de forage superposé
Publication
Application
Priority
DE 4211048 A 19920402
Abstract (en)
[origin: EP0563561A1] A superimposing drilling bit, with a head (1) provided with carbide pins (3) or the like and a shank (2) carrying the head (1), the shank (2) having means (4) for the rotationally rigid connection to a driven inner rod string, and the drilling bit having at least one drilling-fluid line (5), can be improved in particular with regard to its maintenance, without dispensing with the directional accuracy and the cutting efficiency, by the head (1) having a plurality of recesses (6) distributed symmetrically over its periphery and by swivel crowns (7) being arranged in the recesses (6) in such a way that they come to lie inside the diameter of the drilling bit in the swung-in state and project beyond the diameter of the drilling bit to a predetermined extent in the swung-out state. <IMAGE>
IPC 1-7
IPC 8 full level
E21B 7/20 (2006.01); E21B 10/32 (2006.01); E21B 10/38 (2006.01); E21B 10/56 (2006.01); E21B 10/62 (2006.01)
CPC (source: EP US)
E21B 7/20 (2013.01 - EP); E21B 10/327 (2013.01 - EP US); E21B 10/38 (2013.01 - EP); E21B 10/56 (2013.01 - EP); E21B 10/62 (2013.01 - EP)
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
DE 4211048 C1 19930506; DE 59306230 D1 19970528; EP 0563561 A1 19931006; EP 0563561 B1 19970423; JP H0610582 A 19940118
DOCDB simple family (application)
DE 4211048 A 19920402; DE 59306230 T 19930219; EP 93102651 A 19930219; JP 6235593 A 19930323