SAO Flow Meters - Calibration Venturi

SAO ( Smooth Approach Orifice) Flow Meters consist of a machined and polished aluminum body with a brass throat insert. 304 stainless steel is available as an option. Each SAO venturi is calibrated from 10% to 120% of the specified flow rate. An NBS traceable calibration report from CEESI is furnished with the device. HORIBA' s Smooth Approach Orifice calibration venturi has several advantages over Laminar Flow Elements ( LFEs) . Excellent Stability SAOs retain their original calibration accuracy ( unless mechanically abused) , while LFEs experience a slow shift in calibration due to dust collection and filter obstruction. High Accuracy Measurement SAO accuracy is ± 0.5% of reading, while LFE accuracy is typically ± 0.5% of full scale. Therefore, SAO accuracy is higher than LFE accuracy at all flows less than full scale. Minimal Pressure Loss Thanks to a high-efficiency recovery design, SAO calibration venturis experience much less pressure loss than LFEs. At the same flow capacity and pressure rating, an SAO recovers about 80% of measured throat pressure, while pressure drop across an LFE cannot be recovered.