The straight pipe requirement of installation of ultrasonic flow meter

Like many other flowmeters, this ultrasonic flowmeter should be installed upstream of elbows, valves, or reducers. Make sure to allow for the longest possible straight run piping between the meter and the obstacle. The length of straight run can be as short as 5x the piping diameter as long as an additional error of 1% is acceptable.

It maybe tricky when getting the most accurate readings with a ultrasonic flowmeter, even with a top-of-the-line device, as asymmetric velocity profiles, swirl, and other factors caused by bends in pipes can alter reading results with many flowmeters.