Overview

In recent years, the concept of predictive maintenance is gaining increasing attention in industries. Its purpose is to perform diagnosis and maintenance of the equipment when initial abnormality of the equipment is found; so that the failures will not be accumulated and further causing serious damage. Vibration signal is one of the important parameters for fault diagnosis and preventive maintenance. Now most equipment and its structure will generate vibration. By adopting vibration measurement technology, the vibration data can be collected, and the quality of core components such as equipment and bearings can be actively analyzed and maintained in early stage so that the service life of equipment can be extended, unplanned downtime and damage can be avoided. ICP DAS has developed a series of vibration measurement products, providing a variety of different solutions including wireless, wired and high-speed data acquisition which can perform measurement to meet requirements for all kinds of on-site machines in different applications, and then provide result of fault diagnosis and data analysis. According to ISO-10816 standard, "IWSN/iSN Vibration Sensor" series is suitable for sampling low-frequency rotating equipment. The vibration series also have edge computing and self-powered wireless design that make it easy for used in a production line system and can save cost in wiring. "Open controller with e-9K vibration data module", "AR high-speed vibration data logger module", and "signal conditioning module, vibration sensor with PET-7H16M" series can perform can achieve high sampling data analyiss.

 

Application Architecture of the Vibration Products

Applications Suitability Table

 

Vibration Severity

The three parameters commonly used to describe vibrational responses are displacement, velocity, and acceleration. In general, the vibration intensity at low frequency is measured by the displacement value; the vibration intensity at medium frequency is measured by the velocity value; the vibration intensity at high frequency is measured by the acceleration value. For most machines, velocity is the best indicator, which is one reason why many standards use this parameter. The absolute value evaluation of vibration intensity based on ISO 10816-1 (as figure below) is one of the ways to judge whether a machine is in good or bad status according to the vibration value. In addition, based on normal time vibration values, relative judgment methods are also common, where 2 to 3 times are used as warning values and 5 to 6 times are used as abnormal values.
 

 

FFT Analysis

Based on the analysis of displacement, velocity, and acceleration of the time domain signal, the trend of the machine failure can be known, however, the cause of the machine failure maynot be known. FFT (Fast Fourier Transform) is a mathematical operation that converts time-domain signals into frequency-domain spectral graphs. The vibration spectrum can effectively analyze the cause of machine failures. Our products can provide up to 10 sets of spectral values (amplitude/ frequency), and by measuring the radial and axial spectral information of the equipment, the root cause and severity problem of the equipment can be estimated. The faults that may be identified are as follows: