MechChem Africa September-October 2022

Predictive maintenance: route-based vibration checks Test and measurement, communications, process control and equipment solutions specialist, Comtest, describes how best to implement a route-based predictive maintenance routine with the help of modern instruments, such as the Fluke 805 Vibration meter.

based equipment condition monitoring, such as vibration screening. Obviously, not all equipment is created equal, nor is the failure of a particular machine component, so it makes sense to give more attention to machinery that, should it fail, will have the highest impact on overall produc- tion. Many times, the most common culprit for equipment failure is caused by misalign- ment, looseness, imbalance, bearing wear and electrical issues on motors. By implementing route-based vibration screenings and by pri- oritising the right schedule based on an asset criticality list, much of the damage that com- mon machine faults can cause can be avoided. It is imperative to prioritise assets and rank them in order of importance before making schedules, assigning work orders and creating routes. Also, success depends on selecting a qualified assessment team familiar with the various pieces of equipment, then the team can use the quality criteria to gain consensus about why a piece of equipment was included and how it was ranked. Once the assets to be included on the list (by type, size and location, etc.) have been decided on, create a numbering system, such as on a scale of 1 to 5, to rank each asset from ‘most critical’ to ‘least critical’ based on each ones importance to overall production. Now that the asset criticality analysis list is complete, the next step is to establish a preventive maintenance task for each data collection point on the route to accurately screen machine condition changes. Once the maintenance plan has been established and a fixed route of data collection points is in place, start laying out vibration screening schedules and testing frequencies, such as daily, monthly, bi-monthly, quarterly or yearly, depending on the asset criticality ranking and associated risk factors important to the industry, company and plant. Additionally, identify the appropriate technician or engi- neer (less-experienced, semi-experienced, highly-experienced) to address the task, depending on the asset ranking, difficulty of the task and expertise/training needed. For example: • Screening: schedule junior technicians using electrical, thermal and vibration screening tools to monitor equipment: Star machines—daily; critical and semi-

A technician performing vibration screening with the improved Fluke 805 Vibration meter.

S ome of the jobs being performed by today’s technicians don’t even have names or descriptions yet and are be- ing added ‘on the fly’ to keep up with today’s innovative tools and advanced equip- ment condition-monitoring techniques. What was once a complex set of tasks performed only by reliability engineers or specialised contractors, can now be accomplished by less experienced technicians with easy-to- use tools, such as vibration screeners and thermal imagers. Consequently, this allows analysts and reliability engineers to use their time and expertise more efficiently by examining equipment condition data and making proac- tive decisions to prevent equipment failure, ultimately saving money. Training the technician to use high- tech Recently, a large, globally-recognised auto- mobile manufacturer successfully deployed maintenance technicians, who normally repair equipment, to carry out route-based condition monitoring using handheld vibra- tion meters and thermal imagers. Like many plants, the manufacturer had started to incorporate new technology into its operations; however, much of the machinery was still not equipped with sensors so little or no equipment condition data was being gath- ered. Also, no regular condition monitoring

routes or schedules had been set up. Both the company’s thermographer and reliability team supervisor understood the value of equipment condition monitoring with regard to proactive maintenance for extending equipment life. They decided to put vibration screening meters, infrared thermal imaging tools and technicians to the test. “Our main reason for testing these tools was to see if we could pass along some of the vibration testing and thermography scans to maintenance technicians so the reliability team could concentrate on the most difficult issues,” said the Reliability Supervisor. “Right now, we’re only able to look at certain pieces of equipment because we have only so much manpower. If maintenance could collect data on more equipment, and the experts could spend their time analysing the data, we could look at everything more frequently. The tools we use have to make it easy for the maintenance techs to upload the data because we want them to be more efficient.” In the end, the pilot programme proved that techs could be deployed to assist the reliability team. It also provided technicians with a nice change of pace from some of their usual tasks. With the techs now trained and armed with thermal imaging and vibration screening tools, a natural next step for any manufac- turer would be to transition to regular route-

10 ¦ MechChem Africa • September-October 2022

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