EP 0799966 A3 19990203 - Drill bit for percussive drilling
Title (en)
Drill bit for percussive drilling
Title (de)
Bohrkrone für das schlagende Bohren
Title (fr)
Trépan de forage à percussion
Publication
Application
Priority
- DE 19613140 A 19960402
- DE 19619194 A 19960511
Abstract (en)
[origin: EP0799966A2] The drill bit comprises front end cutters, especially hard metal tips, and axially offset mud passages in a drilling disc of the bit. The passages are formed by channels (46) within the disc (36) at spaced (z) from its circumferential surface (42). The bit may have a front end central section, and an adjoining conical ring section, which extends outwards and which slopes towards and merges into the circumferential surface of the disc. The channels (46) can be located at the junction between the central section (40z) and the conical ring section (40k). When the bit has a holder shaft for the disc and, optionally, a stub-like axial initial drilling bit, the holder shaft (16) may be either supported on the disc (36) by an annular collar, in which it is held by tongues, or held in the disc (36) by a toothed or threaded joint.
IPC 1-7
IPC 8 full level
E21B 10/38 (2006.01); E21B 10/40 (2006.01); E21B 17/07 (2006.01)
CPC (source: EP)
E21B 10/38 (2013.01); E21B 10/40 (2013.01); E21B 17/076 (2013.01)
Citation (search report)
- [XA] WO 9424405 A1 19941027 - SANDVIK AB [SE]
- [DA] DE 4326000 A1 19950209 - SRT ROCK TOOLS HANDELS UND PRO [AT]
- [A] EP 0122103 A1 19841017 - HARRISON HUGHES DOUGLAS
- [A] EP 0324150 A1 19890719 - HAWERA PROBST KG HARTMETALL [DE]
- [A] DE 2824958 A1 19791213 - WILLI WADER FA
Designated contracting state (EPC)
AT BE CH DE FR LI LU
DOCDB simple family (publication)
DOCDB simple family (application)
EP 97104925 A 19970322