Sean B Ellis

US Patent:

20040221985, Nov 11, 2004

Filed:

Apr 22, 2004

Appl. No.:

10/830200

Inventors:

Tom Hill - Houston TX, US
Sean Ellis - Houston TX, US
Nicholas Reynolds - Houston TX, US
Nanjiu Zheng - Sugar Land TX, US

Assignee:

T H Hill Associates, Inc. - Houston TX

International Classification:

E21B019/00

US Classification:

166/250010

Abstract:

A drill string design methodology which utilizes a “comparative approach” in the selection of drill string components. The comparative approach in accordance with the present invention can lead to dramatic reductions in fatigue-related problems. In accordance with one aspect of the invention, a method is provided for establishing objective criteria for evaluating individual components of well construction equipment to determine the preferred component or collection of components to be used from the selection of components available. A plurality of quantifiable design parameters relevant to the issues of fatigue damage and failure of drill string components are defined, and an assessment of each of these parameters is made for two or more candidate components being considered for inclusion in the drill string. A comparison is then made between the candidate components' ratings, and a decision to include or exclude a candidate component is made based upon the results of such comparison.

US Patent:

20080319720, Dec 25, 2008

Filed:

Jun 19, 2007

Appl. No.:

11/820471

Inventors:

Sean Eugene Ellis - Houston TX, US
Kang Lee - Houston TX, US

International Classification:

G06F 7/60

US Classification:

703 2

Abstract:

A method for characterizing a threaded coupling such as between two tubular members is disclosed. In one embodiment, a threaded connection between a first tubular and a second tubular is considered, where the first tubular has a internally-threaded box structure and the second tubular has outer threads defining a pin structure. A mathematical model of the connection between the two tubulars is generated, and the mathematical model is permuted to reflect application of at least one flexing force to the joint. From the permuted model, a stress/strain distribution of the box and pin structures is derived. A connection fatigue index value is calculated based on the stress/strain distribution. In one embodiment, connection fatigue indices are computed for a variety of connection combinations, such that a user can compare the relative suitability of multiple box/pin combinations to select one that is deemed desirable for a particular use.