(19) |
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(11) |
EP 1 498 573 A3 |
(12) |
EUROPEAN PATENT APPLICATION |
(88) |
Date of publication A3: |
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24.05.2006 Bulletin 2006/21 |
(43) |
Date of publication A2: |
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19.01.2005 Bulletin 2005/03 |
(22) |
Date of filing: 31.08.1999 |
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(51) |
International Patent Classification (IPC):
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(84) |
Designated Contracting States: |
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GB IT |
(30) |
Priority: |
31.08.1998 US 98466 P
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(62) |
Application number of the earlier application in accordance with Art. 76 EPC: |
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03021140.3 / 1389666 |
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99945375.6 / 1112433 |
(71) |
Applicant: HALLIBURTON ENERGY SERVICES, INC. |
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Carrollton, TX 75006 (US) |
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(72) |
Inventor: |
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- Chen, Shilin
Dallas, TX 75248 (US)
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(74) |
Representative: HOFFMANN EITLE |
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Patent- und Rechtsanwälte
Arabellastrasse 4 81925 München 81925 München (DE) |
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(54) |
Method for designing a roller-cone bit |
(57) Disclosed herein is a method for designing a roller cone drill bit, comprising simulating
the bit drilling through an earth formation wherein the simulating comprises determining
an axial force on a cutting element, based on a means for determining an axial force,
determining an axial force on the roller cones, based on the axial forces on the cutting
elements, and angularly rotating the bit; adjusting at least one design parameter
of the bit; repeating the simulating the bit drilling; and comparing a distribution
of axial forces among the roller cones prior to the adjusting the at least one design
parameter with a distribution of axial forces among the roller cones after adjusting
the at least one design parameter.