DIN ISO 20816-4:2018-02

The document provides specific guidance for assessing the severity of vibration measured on both the bearing housings and the shafts of gas turbines in situ. The criteria provided in this document apply to land-based gas turbines with power outputs greater than 3 MW and a normal operating speed of 3000 r/min to 30000 r/min. This part of ISO 20816 provides specific guidance for evaluating the severity of in-situ, broad-band vibration measured radial (i.e. transverse) to the shaft axis on all main bearing housings or pedestals or on the shaft and in the axial direction on thrust bearings. Two criteria are provided for assessing the machine vibration when operating under steady state conditions. One criterion considers the magnitude of the observed vibration; the second considers changes in the magnitude. In addition, different criteria are provided for transient operating conditions, such as run-up and coast-down.