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Shock pulse method (SPM) is a technique for using signals from rotating rolling bearings as the basis for efficient condition monitoring of machines. From the innovation of the method in 1969 it has been further developed and broadened and is a worldwide accepted philosophy for condition monitoring of rolling bearings and machine maintenance.
Depending on the type of machine, its typical malfunctions, the bearing types employed, rotational speeds, and other factors, the CM specialist may use additional diagnostic tools, such as examination of the time domain signal, the phase relationship between vibration components and a timing mark on the machine shaft (often known as a keyphasor ...
Such a chart can be used in turbine design. Experimentally measured vibration response spectrum as a function of the shaft's rotation speed ( waterfall plot ), the peak locations for each slice usually corresponding to the eigenfrequencies .
A Junker test is a mechanical test to determine the point at which a bolted joint loses its preload when subjected to shear loading caused by transverse vibration.. Design engineers apply the Junker test to determine the point at which fastener securing elements – such as lock nuts, wedges and lock washers – fail when subjected to vibration.
Vibration problems generally result in noise, bad surface quality and sometimes tool breakage. The main sources are of two types: forced vibrations and self-generated vibrations. Forced vibrations are mainly generated by interrupted cutting (inherent to milling), runout, or vibrations from outside the machine.
ISO 21940 [6] classifies vibration in terms of G codes. Unfortunately, it is the theoretical value assuming the rotor was spinning in free space so it does not relate to actual operating conditions. Rotors of the same type having permissible residual specific unbalance value e per, varies inversely with the speed of the rotor. e per × ω ...
Non-intrusive stress measurement (system), or NSMS, is a method for determining dynamic blade stresses in rotating turbomachinery.NSMS is also known by the names "blade tip timing" (BTT), [1] "arrival time analysis" (ATA), "blade vibration monitoring" (BVM), Beruehrungslose Schaufel Schwingungsmessung (BSSM), and "blade health monitoring" (BHM).
In occupational safety and health, hand arm vibrations (HAVs) are a specific type of occupational hazard which can lead to hand–arm vibration syndrome (HAVS). HAVS, also known as vibration white finger (VWF) or dead finger, [1] is a secondary form of Raynaud's syndrome, an industrial injury triggered by continuous use of vibrating hand-held ...