Method for confirming optimal suspension force of offshore test tubular column

Abstract

According to the method for confirming the optimal suspension force of the offshore test tubular column, the optimal suspension force of the offshore test tubular column can be confirmed by testing the tubular column under the conditions of certain transverse acting force distribution coefficient, water depth, tubular column wall thickness and test working condition parameters; the influence of different suspension forces on the maximum transverse vibration displacement and the amplitude of each order of the test tubular column is calculated, so that the optimal suspension force of the test tubular column can be selected, and a basis is provided for adjusting the suspension force during construction of the test tubular column. The offshore test tubular column is determined; the whole tubular column is pulled to avoid complex transverse vibration of the tubular column, the maximum displacement of the transverse vibration of the tubular column is reduced along with the increase of the hanging force at the upper end, the conclusion of the transverse vibration of the test tubular column can be effectively reduced by properly increasing the hanging force of the test tubular column, andtherefore guidance can be provided for mechanical behavior control and safe operation of the test tubular column.

Description

technical field [0001] The invention relates to a method for confirming the optimal suspension force of an offshore test string, belonging to the field of offshore oilfield test operations. Background technique [0002] In the process of testing in offshore oil fields, people need to use the test string to mount various detection equipment, and lower it from the inside of the riser to the designated position for detection. In this process, although the external riser prevents the test string from being directly affected by the marine environment load, the test string is affected by gravity, buoyancy, suspension force, wave force, natural gas force in the pipe, and the impact of the riser on the test pipe. Under the action of the contact force of the column, the lateral self-excited vibration of the test string in the seawater section will be induced. When the lateral vibration displacement of the self-excited vibration of the test string increases to a certain extent, the t...

AI Technical Summary

Problems solved by technology

In this process, although the external riser prevents the test string from being directly affected by the marine environment load, the test string is affected by gravity, buoyancy, suspension force, wave force, natural gas force in the pipe, and the impact of the riser on the test pipe. Under the action of the contact force of the column, the lateral self-excited vibration of the test string in the seawater section will be induced

When the lateral vibration displacement of the self-excited vibration of the test string increases to a certain extent, the test string and the riser will have contact and collision. If the collision and contact are severe, the test string may be damaged and a safety accident may occur.

In order to avoid possible safety hazards, people mainly adopt the method of adjusting the suspension force based on experience to reduce safety risks, but the empirical judgment is not accurate and has no scientific basis, and cannot meet the requirements of production adjustment; therefore, it is necessary to develop an offshore The confirmation method of the optimal suspension force of the test pipe string, so that the enterprise can obtain the optimal suspension force of the test pipe string according to this method during the work process, and then the enterprise can guide according to the value of the optimal suspension force during work Adjust the actual suspension force to achieve the purpose of reducing safety hazards

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