Outwardly mounted nozzles for rotary drill bits

(19)

(11)

EP 0 449 415 A3

(12)	EUROPEAN PATENT APPLICATION

(88)	Date of publication A3:
	27.11.1991 Bulletin 1991/48

(43)	Date of publication A2:
	02.10.1991 Bulletin 1991/40

(21)	Application number: 91301389.2

(22)	Date of filing: 21.02.1991

(51)	International Patent Classification (IPC)⁵: E21B 10/18

(84)	Designated Contracting States:
	DE FR GB IT NL

(30)

Priority:

30.03.1990 US 502046
14.11.1990 US 613241
24.12.1990 US 632949

(71)	Applicant: CAMCO INTERNATIONAL INC.
	Houston, Texas 77054 (US)

(72)	Inventors:
	Moffitt, Stuart R. Houston, Texas 77023 (US) Ivie, Craig R. Houston, Texas 77040 (US)

(74)	Representative: Smith, Norman Ian et al
	F.J. CLEVELAND & COMPANY 40-43 Chancery Lane London WC2A 1JQ London WC2A 1JQ (GB)

(56)

References cited: :

(54)	Outwardly mounted nozzles for rotary drill bits

(57) A rotary drill bit (10) has fluid discharge nozzles (36A, 36B, 36C) positioned between adjacent pairs of roller cutters (20A, 20B, 20C). A fluid discharge nozzle (36A) positioned along the outer circumference of the drill bit body (12) provides a high velocity stream of drill fluid (44) along the bore hole side wall (34) with at least a substantial side portion of the stream (44) engaging the side wall (34) adjacent roller cutter (20A) and flowing downwardly along the side wall (34) across the bore hole corner surface (33). The nozzle orifice (37) has its center (41) positioned less than one inch from the adjacent bore hole side wall (34) and the stream is directed downwardly to provide a minimal change in direction as the stream (44) sweeps across the corner surface (33) and the bore hole bottom surface (32).

Search report