Overflow monitoring method and system based on characteristics of gas cut pressure

Abstract

The invention provides an overflow monitoring method based on the characteristics of gas cut pressure. The overflow monitoring method comprises the following steps that pressure values of different positions on a wellbore are collected to obtain original pressure data of each pressure collection position; pressure derivatives are calculated according to the original pressure data to obtain real-time pressure derivative data; the original pressure data and the real-time pressure derivative data are analyzed to determine the time and position of the overflow; the cumulative overflow volume is calculated according to the time and position of the overflow, and the volume flow data of an outlet and an inlet of the wellbore, and whether an overflow early warning needs to be issued or not is judged according to the cumulative overflow volume. According to the overflow monitoring method, the early monitoring requirements of gas cut overflow in a deep well, an ultra-deep well and a complex stratum can be met; the overflow monitoring method is not affected by the parameters of the stratum, the well depth and the like; the real-time overflow volume is accurately calculated without being affected by environmental temperature, pressure and the like; and the method is easy to achieved, the monitoring effect is obvious, and the needs of complex deep well overflow monitoring can be met.

Description

technical field [0001] The invention relates to the field of oil drilling, in particular to an overflow monitoring method and system based on gas intrusion pressure characteristics. Background technique [0002] Due to the characteristics of compression and expansion of gas, after the gas invades the drilling fluid, the volume of the gas is very small due to the pressure of the upper liquid column at the bottom of the well. The pressure of the liquid column will also gradually decrease, and the gas volume will gradually expand and increase, especially when the gas is close to the ground, the gas expansion will increase rapidly. During the drilling process, if effective degassing measures are not taken, the gas-invasion drilling fluid will be repeatedly pumped into the well, which will make the degree of drilling fluid gas intrusion more serious, resulting in a continuous decrease in bottom-hole pressure and the risk of overflow . [0003] Existing equipment and monitoring ...

AI Technical Summary

Problems solved by technology

The entire measurement system is affected by various factors such as the measurement accuracy of the flowmeter, installation conditions, measurement principle, and actual situation constraints, and it is difficult to guarantee the measurement accuracy.

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