Monitoring machine vibrations affords greater control over the safety and availability of the equipment. It reduces unscheduled downtime and potential damage or failure can be resolved at an early stage. The main effects of undetected, critical machine vibrations are described below.
Safety within a plant must be guaranteed at all times. Although the sources of vibrations can usually be resolved easily at an early stage, they can develop into serious safety issues if action is not taken when required. Not only can unidentified machine vibrations cause serious damage, more importantly, they can cause human injuries and environmental harm.
When critical vibrations are not identified at an early stage, (serious) damage to the machine can occur. In the most extreme cases, the machine must be replaced entirely as a result of excessive damage.
As a result of increasing vibration, it may be necessary to reduce the machine load, e.g. rotational speed or output. This leads to reduced availability.
Vibrations often develop gradually and can be hard to detect without proper instrumentation. As soon as they become apparent, it is usually too late to take preventive measures and only mitigating measures are possible. Mitigating measures can only limit the effects of excessive vibrations, and damage may have occurred already. Mitigating measures are difficult to schedule and as a result unscheduled downtime is unavoidable. This leads to high costs because many plants in the process industry must be continuously operational. When machine vibrations are monitored properly, maintenance can be planned based on the vibration trend. This trend is built using long-term vibration data and allows the prediction of the future maintenance requirements.
Many companies have to adhere to certain supply agreements. An unscheduled stop or reduced availability, as a result of defective machine parts or excessive damage, is likely to lead to the inability to comply to these supply agreements. This can lead to customer dissatisfaction and fines (in business-to-business agreements).
Machine parts are often replaced preventively to ensure that the machine is available at all times. Although this prevents unscheduled downtime, there is a good chance that machines or machine parts are replaced unnecessarily, before the actual end-of-life. By monitoring the machine vibrations, repairs and replacements are only performed when needed.
When a machine has to be stopped or fails unexpectedly, semi-finished products remain in the process. In many cases, these semi-finished products must be discarded, meaning that expensive raw materials are essentially thrown out or led to the flare.
Although a machine seems to run properly, this is not always the case. Vibration measurements and analyses are helpful to determine potential malfunctions. If this does not take place, the quality of the manufactured products may drop or cannot be guaranteed.