Vibrodiagnostics is one of the methods of predictive support of maintenance. It consists in measuring vibrations of a machine and analysing them in search for the symptoms of developing failures. For many years, it has been broadly applied in sectors such as energy, chemical and paper industry, and many others. The history of applying vibrodiagnostic methods in open cast mining is also quite long - particularly in the area of gear monitoring - and with the development of ATEX-approved technologies vibration monitoring systems are increasingly often applied in underground mining.
Vibrodiagnostics in mining
Due to the progressing transformation within the framework of Industry 4.0 as well as the emphasis on the application of maintenance techniques supporting Predictive Maintenance, the underground mining industry is becoming increasingly interested in the application of vibrodiagnostics in machine monitoring. It must be remembered that measuring and processing vibrations with regard to equipment diagnosis in underground mining is a challenge which has been taken on by mines, machine manufacturers and diagnostic system providers for many years. Experiences to day show that due to the high variability of the conditions in which mining machines operate as well as the equipment limitations resulting from the ATEX requirements, complex vibrodiagnostics of equipment, such as roadheader gears and chain conveyors, is a task much more difficult than in other industries, however, not impossible.
Following the requirements of the underground mining market, FAMUR Institute, a research and development unit belonging to the FAMUR Group, has expanded its services by providing measurements using a fully intrinsically safe portable device for vibration measurement. The device enables advanced vibration diagnostics of machines using vibration analysis methods and the use of the SPM method, dedicated to rolling bearings. In addition to the increase in typical diagnostic capabilities, the competencies and equipment of FAMUR Institute enable synchronous, long-term recording of the vibration signal or intrinsically safe voltage inputs with sampling frequencies, enabling analysis of dynamic phenomena as well as solving problems in drive and power systems.
Apart from increasing their capabilities by acquiring modern measuring equipment, the employees of FAMUR Institute are constantly developing their competencies in the field of practical vibrodiagnostics and vibration analysis. It was confirmed by the the VIBRATION ANALYST: CATEGORY II certificates, granted by Mobius Institute, a certification body from Australia.
Competencies acquired this way, supported by extensive experience in industrial vibration measurement, enable not only technical condition diagnosis itself, but also effective optimisation of the operating conditions in the context of occurring vibrations, which brings an actual effect in the form of increased durability of the machines supplied.
Fig. 1. Example of vibrodiagnostic analysis of a drive system. Properly conducted analysis enables the development of solutions reducing vibrations of the system and the improvement of its operating conditions, which results in longer failure-free operation time.
Vibration control as quality control
At FAMUR Group, vibrodiagnostics not only supports decisions in the field of maintenance, but is also a part of quality control in the field of acceptance tests of gears. Every drive system undergoing the test process at FAMUR test station is included in the vibration test programme. The recording takes place continuously, in synchrony with other parameters, such as rotational speed, load, temperature, etc. The collected signals are processed on an ongoing basis and analysed by FAMUR Institute and FAMUR quality control department in order to assess the quality of gear and control the process of breaking in.
Fig. 2. Gear installed at FAMUR testing station. The online vibration monitoring constitutes one of the stages of quality control during breaking in and acceptance tests.
The development of intelligent sensors and measurement solutions with diagnostics and processing algorithms embedded in them are part of the technological revolution of Industry 4.0. Such solutions include the SmartCheck Scheafler system, manufactured by FAMUR and applied in surface gears; the system consists of intelligent vibration sensors with built-in diagnostic algorithms designed for machines working in variable operating conditions. As an integrator, FAMUR Institute carries out projects and diagnostic system implementations in the gears manufactured by FAMUR Group based on the SmartCheck system, in this respect focusing mainly on the open cast mining industry. The FBWG Diagnostic Systems based on SmartCheck sensors are already a standard for, among other things, key drive gears in bucket wheels provided by FAMUR. Close cooperation with Scheafler enables optimal configuration of the system for the purposes of monitoring a specific system. The systems are also capable of monitoring virtually any process parameters of gears, including speed, temperatures, pressures and oil flow. The scalable architecture and the use of a wide range of IoT communication standards enables integration with any machine monitoring system operating at the facilities of the final customer.
Fig. 3. One of the FBWG Diagnostic System sensors, installed on the bucket wheel gear.
Machine diagnostics, constituting a support for maintenance policy, is one of the pillars of successful implementation of the broadly defined Predictive Maintenance strategy. As a provider of key machines for the mining industry and through the involvement of FAMUR Institute, FAMUR Group is constantly increasing its competencies in the field of vibration diagnostics and other measurement forms of maintenance support. It comprises an increase in the scope of the offered services in the area of diagnostic measurements and expert opinions as well as the development of diagnostic systems permanently installed in the delivered machines.