Simulation experiment method for determining average thickness of rock debris bed based on pressure difference

Abstract

The invention discloses a simulation experiment method for determining an average thickness of a rock debris bed based on pressure difference. The simulation experiment method comprises the followingsteps that 1, a simulated wellbore, a simulated drill string and at least two pressure gauges are arranged; 2, drilling fluid is injected into the simulated wellbore, the simulated drill string is controlled to rotate, rock debris is injected into the simulated wellbore, a discharge rate for injecting the drilling fluid and pressure values detected by the pressure gauges are separately obtained, and a pressure difference between the two adjacent pressure gauges is obtained; 3, an average flow rate of the drilling fluid between the two adjacent pressure gauges is calculated according to the result of the step 2; 4, an average cross-sectional area of an annulus between the two adjacent pressure gauges is calculated according to the result of the third step; 5, an average ratio of a rock debris bed to the simulated wellbore between the two adjacent pressure gauges is calculated according to the result of the fourth 2; and 6, an average thickness of the rock debris bed between the two adjacent pressure gauges is calculated according to the result of the step 5. According to the method, the average thickness of the rock debris bed in a water-based / oil-based drilling fluid state is determined according to the pressure difference, the cost is lower and the determining effect is better.

Description

technical field [0001] The invention relates to the technical field of petroleum drilling, in particular to a simulation experiment method for judging the average thickness of a cuttings bed based on a pressure difference. Background technique [0002] During the drilling process of highly deviated wells and horizontal wells of oil and gas, cuttings often fail to migrate smoothly and form cuttings beds, which leads to complex problems such as increased friction and poor drilling, and even affects drilling safety in severe cases. With the continuous extension of the horizontal section, the problem of cuttings beds in horizontal wells with long horizontal sections becomes more prominent. How to effectively judge the state of cuttings beds in the horizontal section is the focus and hotspot of current research. [0003] At present, it is an effective method to study the cuttings bed migration law in the horizontal section of the downhole by using the ground simulation experiment...

AI Technical Summary

Problems solved by technology

[0005] 1. Due to the addition of various chemical substances in the drilling fluid, the working environment of the ultrasonic probe is harsh, and it is easily affected by the drilling fluid, resulting in abnormal signals and failure to work;

[0006] 2. Affected by the flow of drilling fluid, the measurement accuracy and sensitivity of the ultrasonic probe will be reduced, resulting in inaccurate measurement

[0007] 3. The price of the ultrasonic probe is relatively high, which leads to a correspondingly high measurement cost

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