(REVIEW OF THE DRILL STRING DESIGN GUIDELINES FOR DRILLING IN WATER AREAS)
The article deals with the following challenge: according to the oil and gas drill string design guidelines of 1997, which is used by most specialists in the industry, a bending moment and stresses in the drill string body are calculated only at the wellhead and at the water area bottom, i. e. these guidelines do not specify what values these parameters will have, for example, at 100 m from the rotor table. We examine approaches to addressing the challenge described. The article discusses the problem of aligning the results of calculations in line with the above guidelines and A.Ye. Saroyan equation for horizontal displacement of a drill ship. The article does not cover rolling, waves, and currents affecting the drill string. The purpose of the study is to find how to solve the A.Ye. Saroyan equation under the boundary conditions derived from calculations under the 1997 guidelines for the wellhead and water area bottom.
The conclusion outlines the stress analysis under the guidelines can be supplemented by the solution of the А.Ye. Saroyan equation, subject to the conventional deflection of the drill string is obtained. Then it is possible to calculate the stresses in the pipe body at any point, not only at the wellhead and water area bottom, but also within water areas during horizontal displacement of a ship.
B.A. Korotaev, Murmansk State Technical University (Murmansk, Russia), email@example.com
F.N. Yangirov, PhD in Engineering, Associate Professor, Ufa State Petroleum Technological University (Ufa, Russia), firstname.lastname@example.org
M.V. Subbotina, Murmansk State Technical University, email@example.com
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