Flowmeter with pipe diameter detection function

The utility model discloses a flow meter with a pipe diameter detection function. The flow meter comprises a measuring pipe, a fluid inlet, a fluid outlet, a first turbine, a flow displayer, a throttling plate, a driving assembly and a detection assembly. The driving assembly comprises a driving seat communicated with the measuring tube, a screw rod which is in threaded connection with the interior of the driving seat and one end of which is movably connected with the throttling plate, and a second turbine which sleeves the screw rod; the detection assembly comprises a detection seat, a detection disc arranged on the detection seat, a measurement rod inserted in the detection seat, and a third turbine connected to the other end of the measurement rod, wherein one end of the measurement rod is rotatably connected with the detection disc; and the second turbine is in transmission connection with the third turbine. According to the flow meter, the flow displayer, the throttling plate, the second turbine, the thi