Method for simulating cementation failure caused by temperature change

Abstract

The invention discloses a method for simulating cementation failure caused by temperature change. The method comprises the steps of mounting a bushing component and injecting cement slurry into the bushing component; placing the bushing component into a high-pressure kettle of a test device, and closing the tops of the bushing component and the high-pressure kettle; filling the bushing component with high-pressure oil, and heating the bushing component; pressurizing a ring space between the high-pressure kettle and the bushing component, heating the high-pressure kettle, adjusting the temperature and the pressure in the high-pressure kettle to be consistent with the temperature and the pressure under an actual downhole working condition, and maintaining the cement slurry until a cement ring is molded; keeping the pressure between the high-pressure kettle and the bushing component and in the bushing component to be constant, detecting whether gas channeling exists between the cement ring and a bushing in a temperature change process by repeated heating and cooling, and measuring a gas channel amount, wherein a formula of the cement ring which can be repeatedly heated and cooled for most times is taken as the best formula. According to the method, simulation of an engineering working condition is realized indoors, data and parameters which have guiding significance for the engineering practice are obtained, and the optimal formula of the cement ring can be found.

Description

technical field [0001] The invention relates to a test method for indoor simulating cementation in well cementing, in particular to a test method for indoor simulating the influence of temperature changes on cementation in cementing. Background technique [0002] In well cementing, the sealing performance of the cement sheath to the formation is of great significance to the production safety, life of the oil and gas well and the benefits of oil field development. The cement sheath with high sealing and channeling ability is safe and environmentally friendly to develop the oil layer and realize the maximum exploration and development benefits. an important basis for transformation. [0003] Actual production experience shows that after the cement slurry is replaced in place, the CBL / VDL test shows that the well with good cementing quality will undergo subsequent drilling, drilling fluid density increase, formation integrity test, perforation, fracturing, temperature change, p...

AI Technical Summary

Problems solved by technology

At present, the equipment generally cannot guarantee that the cement slurry can be cemented in the same set of equipment and the temperature-bonding failure experiment is carried out, which is inconsistent with the actual working conditions;

[0008] 3) Gas channeling cannot be quantitatively evaluated

In terms of the length of the simulated cement sheath, it is generally less than 50cm, and the length is too small, which cannot fully reflect the problems existing in the actual working conditions in the experiment;

[0010] 5) The scope of inspection is not comprehensive

It is impossible to detect the working condition that a micro-annulus is formed in the middle of the height direction of the cement sheath and the two ends are well cemented

[0011] 6) High experimental cost

The inner casing cemented with the cement sheath, the outer artificial formation or the casing are scrapped after one experiment, resulting in high cost of experimental research

[0012] 7) The parameters of the experimental conditions are low, and it is impossible to simulate the working conditions of high temperature and high pressure wells at the same time

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