(19)
(11)EP 1 158 137 A3

(12)EUROPEAN PATENT APPLICATION

(88)Date of publication A3:
19.05.2004 Bulletin 2004/21

(43)Date of publication A2:
28.11.2001 Bulletin 2001/48

(21)Application number: 01203040.9

(22)Date of filing:  28.02.1997
(51)International Patent Classification (IPC)7E21B 43/10, E21B 43/30, E21B 41/00, E21B 7/06
(84)Designated Contracting States:
DE FR GB IT NL

(30)Priority: 11.03.1996 US 13227
27.08.1996 US 25033
11.02.1997 US 798591

(62)Application number of the earlier application in accordance with Art. 76 EPC:
97301356.8 / 0795679

(71)Applicants:
  • Anadrill International SA
    Panama City (PA)
    Designated Contracting States:
    DE GB IT NL 
  • SERVICES PETROLIERS SCHLUMBERGER
    75007 Paris (FR)

(72)Inventor:
  • Ohmer, Herve
    Houston, TX 77079 (US)

(74)Representative: Macquet, Christophe 
Schlumberger Cambridge Research Ltd, High Cross, Madingley Road
Cambridge CB3 0EL
Cambridge CB3 0EL (GB)

  


(54)Method and apparatus for establishing branch wells at a node of a parent well


(57) A plurality of recording heads capable of ejecting inks of different colors is reciprocated relative to a recording material to print ink dots on the recording material while effecting main scanning in the forward and the backward pass thereof. A plurality of thinning patterns produced by preparing m x n unit picture element groups and arraying these unit groups in such a manner that the groups avoid mutually adjoining and assume a mutually complementary relation is used to effect a plurality of rounds of main scanning in the forward and the backward pass over an area which can be printed by one round of main scanning, record a thinned image, and complete the recording of an image. The array of picture element groups in the thinning patterns is determined so that the groups may mutually adjoin relative to the direction of main scanning.










Search report