Method for monitoring average sand production rate of oil and gas well

The invention discloses a method for monitoring the average sand production rate of an oil and gas well. The method comprises the steps that an ultrasonic probe is used for transmitting and receiving ultrasonic signals in an elbow pipe perforation accident high-incidence area; acquiring and recording residual wall thickness information of the pipeline according to the principle of an ultrasonic pulse reflection method; the difference value of the residual wall thickness of the pipeline recorded before and after the fixed monitoring time is substituted into the erosive wear equation; and the sand production mass flow is calculated according to the erosion rate determined by the erosion wear equation. According to the invention, the erosion wear equation is utilized to calculate the sand production rate, the influence of single measurement error and accumulative error in the monitoring process is avoided, only the pipeline wall thickness value in a fixed time length needs to be measured, the circuit is simple, the processing system is simple, the equipment reliability is high, the implementation is more accurate, and the failure of pipeline perforation can be found in time before the failure of pipeline perforation. And equipment can be replaced in time.