Yes, clamp-on ultrasonic flow meters strictly require straight pipe sections to ensure stable flow profile and accurate measurement.
Standard Straight Pipe Requirement
Upstream (before sensors): 10 times pipe diameter (10D)
Downstream (after sensors): 5 times pipe diameter (5D)
Extra Straight Pipe for Special Fittings
If there are pipe fittings nearby, longer straight pipe is needed:
After 90° single elbow: 15D upstream
After two elbows in different planes: 20D~30D upstream
Near pump outlet, valve, reducer or expansion joint: Keep minimum 15D~30D straight pipe
Installation Forbidden Area
Do not install the ultrasonic sensors directly next to:Elbows, pumps, butterfly valves, gate valves, flow regulators, reducers, or any positions with turbulent flow.
Ultrasonic flow meters rely on stable laminar flow. Turbulent and irregular flow caused by pipe fittings will lead to unstable readings, big deviation or no signal.
Post time: Apr-27-2026