Accelerometer Mounting on Piping Systems: Experimental Study on a 20-mm-Diameter Curved Surface

Assessments of vibration signals measured on surfaces of piping systems are essential in prevention of vibration-induced failures. Magnets, piezoelectric accelerometers, and hand-held vibration analysers are typically used for those assessments. ISO 5348–2021 “Mechanical Vibration and Shock—Mechanical mounting of accelerometers” provides a guideline of the correct mounting of accelerometers on flat surfaces. However, it offers limited information regarding the mounting of accelerometers on curved surfaces. This technical note focusses on the mounting of accelerometers on 20-mm-diameter curved surfaces. Experimental studies with sinusoidal signals were conducted using magnetic and non-magnetic metallic materials, small and large accelerometers and six common mounting methods, i.e. beeswax, cyanoacrylate glue, dual-rail magnet, flat magnet, hand-held and thin double-sided tape. For each mounting method, a frequency response plot of the relative sensitivity of the test accelerometer with respect to the reference accelerometers was obtained for frequencies ranging from 2 Hz to 10 kHz. The plots were used to determine mounting frequency limits by identifying points that deviate more than 3 dB from the reference sensitivity. For magnetic curved surfaces, the dual-rail magnet and glue methods exhibited the highest frequency limits. For non-magnetic curved surfaces, a thin strip of double-sided tape was required, but it only worked for small accelerometers. Hand holding an accelerometer is not recommended. Future work is needed for transient signals.