Global Patent Index - EP 0408667 B1

EP 0408667 B1 19940119 - ACOUSTIC DATA TRANSMISSION THROUGH A DRILL STRING.

Title (en)

ACOUSTIC DATA TRANSMISSION THROUGH A DRILL STRING.

Title (de)

AKUSTISCHE DATENÜBERTRAGUNG ÜBER EIN BOHRGESTÄNGE.

Title (fr)

TRANSMISSION DE DONNEES ACOUSTIQUES AU TRAVERS D'UN CORDON DE TUBE DE FORAGE.

Publication

EP 0408667 B1 19940119 (EN)

Application

EP 89905949 A 19890421

Priority

US 18432688 A 19880421

Abstract (en)

[origin: WO8910572A1] Acoustical signals are transmitted through a section of drill string (30) by cancelling upward moving acoustical noise and by preconditioning the data in recognition of the comb filter characteristics of the drill string. Spaced sensors (52, 54) provide a delayed signal to summer (46) which is combined with a signal from suitable circuitry (28) and then applied to sensors (42, 44) for transmitting an uphole signal having no downward moving noise.

IPC 1-7

G01V 1/40; E21B 47/12; G10K 11/24

IPC 8 full level

E21B 47/16 (2006.01); G01V 1/40 (2006.01)

CPC (source: EP)

E21B 47/16 (2013.01)

Designated contracting state (EPC)

DE FR GB NL

DOCDB simple family (publication)

WO 8910572 A1 19891102; DE 68912584 D1 19940303; EP 0408667 A1 19910123; EP 0408667 A4 19910814; EP 0408667 B1 19940119; JP H03501408 A 19910328

DOCDB simple family (application)

US 8901641 W 19890421; DE 68912584 T 19890421; EP 89905949 A 19890421; JP 50585689 A 19890421