(19)

(11)

EP 1 597 439 A1

(12)

(43) Date of publication: 23.11.2005 Bulletin 2005/47 (21) Application number: 04713269.1 (22) Date of filing: 20.02.2004

(51) International Patent Classification (IPC)7: E02F 3/92, E21B 21/12 (86) International application number: PCT/NL2004/000130 (87) International publication number: WO 2004/074586 (02.09.2004 Gazette 2004/36)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR Designated Extension States: AL LT LV MK (30) Priority: 20.02.2003 NL 1022749 04.03.2003 NL 1022832 04.03.2003 NL 1022833 (71) Applicant: Baggermaatschappij Boskalis B.V. 3350 AA Papendrecht (NL)	(72) Inventors: BODEGOM, Dirk, Albertus NL-2861 VJ Bergambacht (NL) NOBEL, Arnold, Johannes NL-3333 XH Zwijndrecht (NL) ROSENBRAND, Willem, Floris NL-3352 BA Papendrecht (NL) (74) Representative: Nederlof, Etienne C.  Octrooibureau Vriesendorp & Gaade B.V., Postbus 266 2501 AW Den Haag 2501 AW Den Haag (NL)