Flashing forward in time, we find that our needs are much the same as those primitive people. We need, food shelter and place to ‘go to the bathroom'. Modern waste treatment facilities, though essential to population density, are given finite funding and must use it wisely. Therefore, it is vital for these entities to approach all their efforts effectively. In simple words; is what we are doing giving best return?
The Art of Asset Management
To these ends operating a wastewater treatment plant as a world class enterprise makes best sense. To achieve this level the plant operators need to organize by modeling best practices and develop substantial knowledge of their own unique operating environment. Implementing Predictive Maintenance (PdM) adds great value and helps to navigate in an inconsistent, illogical and disorganized world.
Predictive Maintenance after all is simply using scientific tools to help determine asset condition. The top tool for most machines is vibration analysis, adding other technologies (ultra-sound, oil analysis, thermal and electrical analysis) enhance the results.
It is vital to define the overall parameters for business, operations, maintenance, HR and other attributes for a PdM program to work. Parameters say how much is spent on repair before replacement, when to use contractor labor, how to decide staffing level, and how compensation is set. These parameters can be incorporated into a business plan or mission statement. If they are not in place, this needs to be resolved before proceeding.
Maintain these parameters consistently while constantly analyzing and reviewing their effectiveness.
Record Keeping
In defining the parameters it will be necessary to create the all important Master Equipment List often referred to as the EM (equipment master). These records contain vital information necessary for maintenance and operation. These records must include easily understandable unique identifier for the equipment (alphanumeric code that designates location, type & serialization) for each piece of equipment. PdM readings (vibration, temperature etc.) are identified by this code on the PdM Data Collector. These identifiers appear on equipment in the field (bar codes, stamped tags and other markings) to allow accurate reporting to a CMMS.
These records must be organized by process, location, system and component levels. Having data for costs for acquisition, power consumption and upkeep will aid Finance Departments in valuation and improve making decisions of when to replace versus when to repair. This requires simple workable rules; decision trees are helpful for this purpose. When acquiring or disposing of assets the EM is updated and procedures shall exist to make this to happen.
The one very important value that all assets require is a criticality rating to help assess priority given to its function and maintenance. Again, in simple words, what will it cost if it fails? Think in terms of overall and collateral losses due to failure. This value helps drive the choice to apply Interval Maintenance, PdM or allow the asset to run to failure (RTF). Again, decision trees tailored to the enterprise will help determine the proper criticality level for the asset.
Another valuable code to put in the EM is machine class for vibration. This will designate the allowable vibration limit.
With a record structure in place decision making processes and business practices are developed from working knowledge of the enterprise. As the enterprise matures, the knowledge becomes more substantial and provides historical comparisons. The melding of substantial knowledge and organization provide guidance and a framework for managing the enterprise effectively.
The Technologies
Maintaining assets requires several view points on the level and type of maintenance. In the case of wastewater treatment facilities permanent concrete structure are as essential as the rotating machinery moving the water through the processes. Concrete and other permanent structures are evaluated through various inspection processes generally on an interval basis.
Qualified rotating machinery is also monitored on interval basis. PdM trending is performed quarterly for most machines and more frequently if needed. Invest in personnel to perform PdM and work to retain them. They are the critical piece in the puzzle. Develop stakeholders not just technicians. Train them and allow them to create their own work plans. If they identify imminent equipment failure, plan, schedule and execute the fix. This will help them feel empowered and want to dig deeper for more savings. Monitor and reward their successes; what you want are people who will go after the root cause of failure.
Using contractors to perform PdM can provide benefits, but also requires resource to manage. Develop in house personnel for PdM and use contractors as a supplement.
Six Sigma
Six Sigma methods provide a solid means to ferret out failure causes and means to correct. Since this is a discipline unto itself, it is only mentioned here.
Implementing the Technologies
There is always a gulf between theory and practical application. Technology should support people, not the other way around. If a program requires too much ‘care and feeding', it is time to look at the value it produces and how it being managed.
Predictive technology instruments require training, calibration and procedures. The best PdM Data Collector will provide no benefit if it languishes in a drawer where it has been put out of sight and out of mind. In choosing personnel to use these technologies, be certain they are self-starters that will not be deterred by the naysayer and reactionary.
Buying the most expensive instruments is not a substitute for knowledge and experience. A technician can ‘know a lot' but understand little and this can lead to poor data and poor decision-making.
The PdM technician/engineer is essentially an asset actuary. For them failure modes are second nature. They know the common failure modes of their equipment (heat, vibration, lubrication, electrical etc.). They know the crash points. They understand when to launch corrective actions.
Assessing Gains and Losses
Having financial, lifecycle and maintenance data from the EM and CMMS allows decision makers to choose best action. This requires workable methods to validate decisions. The math for this process is basic, but the substantial knowledge of the enterprise is complex.
Example- What does it cost if a blower fails in a given process? Failure to meet environmental requirements, loss of process and un-anticipated expense go into the calculation.
Factors - Takes into account all additional costs to continue processes while corrective work proceeds especially if a critical process is affected. It is wise to add a value for the un-anticipated factors. The factors can involve hiring contractors, outside engineers, overtime, materials and equipment rental. Be certain to account for fines that can be levied by local, state or national authorities.
The Bottom Line - Can PdM find the problem before the equipment fails and allow for efficient repair? Write the factors out on cards if necessary and arrange then on a table. Create flow charts to display the possible situations. Find the flow chart that get best results then use it to guide action.
Proof -After costs are logged to the General Ledger, pull out reports that compare final costs to similar situations. If the costs are lower and the MTBF is higher, you're on the right track.
Comprehensive Program
Work to get all levels of staff and workforce to accept and embrace PdM technologies. These technologies have proven benefits. Show the trades people the ROI of predictive maintenance and develop their stake in successful utilization.
Analyze, Change, Test, Repeat
Advances in technologies associated with wastewater treatment, and maintenance will occur; they must be reviewed, verified and incorporated. This is what modern programs of Management of Change and Six Sigma address.
Conclusion
The foregoing principles are largely self-evident. The goal of this piece is to put them into a memorable form for action. The quest of ROI is not simply saving money. Additional benefits include improved safety and reliability.
It is essential to find out what management wants, boil it down to a short statement and post it next to your primary workstation. These Priorities shall be adhered to and executives must signify their agreement with these priorities. This leads to consistency. Let us get to work. Good Luck!
