The invention relates to a device for measuring a return flow of L-shaped communicating
pipe drilling liquid and a method for measuring a return flow of L-shaped communicating
pipe drilling liquid. The device for measuring a return flow of L-shaped communicating
pipe drilling liquid consists of an optical
liquid level sensor, an L-shaped communicating pipe, a
flare pipe, a communication pipe bracket, a
signal conditioning and pre-
processing device, a data acquiring unit, a
client computer and a sound and light
alarm device, wherein the pipeline of the
flare pipe is provided with an L-shaped communicating pipe; the L-shaped communicating pipe and the
flare pipe form a communicating vessel; the vertical position of the window of the L-shaped communicating pipe is positioned between a pipeline
flange plate of the flare pipe and the lower edge of a return pipeline; the circumferential direction of the window of the L-shaped communicating pipe anticlockwise rotate between the extended lines of the return pipeline
central line from the intersecting line of the return pipeline and the pipeline of the flare pipe; and the optical
liquid level sensor is arranged on the L-shaped communicating pipe bracket. In the invention, the pre-warning time is early; the detection precision is high; workers at the drilling site have more
sufficient time to close the well; and blowout accidents are effectively prevented.