What is precision maintenance?
Precision maintenance is an approach that can be implemented alongside any other maintenance strategy such as preventive, predictive, or prescriptive. While the other strategies focus on the when of maintenance, precision maintenance is focused on the how.
A precision maintenance program is an approach to maintenance where teams will use standard operating procedures to improve equipment reliability.
Whether the task is aligning a shaft, reducing machine vibration, or fastening a bolt, precision maintenance leaves no room for technician discretion, imposing clear thresholds, tooling, and techniques to ensure the task meets industry best practices.
Why is precision maintenance important?
Even when given the same set of procedures, maintenance technicians will often complete maintenance tasks differently. Each will read and understand work orders differently and have varying perspectives on the meaning of vague instructions.
This is called variability. In production and maintenance, variability is the root cause of failing to achieve a quality outcome.
The result is that the same task, when completed by different technicians, yields different results — which can lead to poor maintenance reliability.
Defining precise steps for completing maintenance tasks will help you get rid of inconsistencies, and create more precise results.
While it takes a lot of effort and determination (and probably some nagging), optimizing the execution of maintenance work to such a high degree leads to palpable benefits:
Prerequisites for running a precision maintenance program
A precision maintenance program requires your business to have several supporting systems already operating well in the background.
Well-trained and motivated maintenance technicians
Attitude is as important as experience and skill set. Precision maintenance requires technicians with hands-on experience, who understand the importance of diligent task execution and strict compliance with processes and procedures.
An effective preventive or predictive maintenance program
Implementing a precision maintenance strategy requires having a clearly defined performance baseline against which to identify improvement. Unless the maintenance program is up to date and in control, a business will fail to recognize the impact of precision maintenance and justify its investment.
Effective and repeatable best-practice work procedures
Ensure all maintenance tasks have standard operating procedures to guide the technician, supported by detailed workflows.
The procedures must clearly define the standards, tolerances, tension, torque, and the fits that the technician must achieve during task execution. Procedures must include best-practice methods and guide the technician to the correct maintenance documentation.
A system supporting continuous improvement
Use a continuous loop system to capture failures, analyze them, and take corrective action to prevent reoccurrence. For instance, a failure reporting, analysis, and corrective action system (FRACAS) can work in parallel with a precision maintenance program to continuously improve equipment and technician performance.
High-quality, calibrated measuring tools
Precision maintenance requires high-precision measuring tools. “I think it’s near-enough” is not good enough if you are in the process of shaft alignment, measuring vibration levels, or need to torque fasteners to a precise torque reading.
The tools technicians and mechanics use need to provide reliable and repeatable measurement capability, calibrated for accuracy. Tasks like precision alignment are mission-critical procedures, and your precision standards must be up-to-par.
High-quality spares and consumables
Original equipment manufacturers (OEM) will specify the spares and consumables for their products to ensure the equipment operates as designed. Using cheap alternatives to save money may shorten the equipment’s life and introduce reliability issues that will be difficult to identify in service.
A modern, capable maintenance management system
Precision maintenance requires a rigorous maintenance management system to remove variability and build a centralized maintenance repository that provides access to reliability records and a planning database.
To manage a large volume of data, most organizations rely on a modern computerized maintenance management system (CMMS) to store, manage, and access the required maintenance data.
4 steps for implementing a precision maintenance program
Once you have the resources to run precision maintenance effectively, it’s time to tie them into a program. The process can be broken down into four steps.
1. Agree on a statement of intent
To successfully implement a precision maintenance strategy, everyone needs to be on board. At this stage, you will need to draft a statement of intent that describes what the business hopes to achieve by implementing precision maintenance.
Avoid high-level prose and flowery words. Focus on key quantifiable objectives from which you can devise metrics for an ongoing monitoring of program effectiveness.
2. Select the equipment
Start slowly and deliberately. Don’t select the worst machines in your production line as the guinea pigs for your new precision maintenance program.
These machines have layered, complex issues requiring resolution. Trying to prove a new program on such a piece of equipment will set you up for failure.
Instead, choose machines in the middle of the reliability pack, with underlying reliability issues that might be resolved through improved maintenance processes. Making precision maintenance a part of your CNC maintenance program might be a good idea if the machine(s) satisfy the criteria mentioned above.
3. Carry out a measuring tool inventory
Ensure you have all the measurement tools required to allow the execution of maintenance tasks on your selected machines. For example, the range of torque wrenches should cover all possibilities that technicians could encounter on your machinery, from in/lb torque screwdrivers to ft/lb wrenches with 1/2″ or 3/4″ drives. Ensure your equipment is properly calibrated.
Vibration and temperature monitors, micrometers and vernier calipers, laser alignment tools, and dial indicators must be readily available, in good condition, and must provide reliable, repeatable measurements.
4. Create the necessary documentation
Precision maintenance requires the creation of three-level documentation.
The operational level includes the processes and procedures the technician will carry out on a specific machine. These worksheets or planned maintenance tasks provide a standard method of completing the scheduled task, including workflows and sequences where necessary.
They will find the correct maintenance documentation and define torque ranges for each fastener, the acceptable vibration or temperature thresholds, clearances, fits, and pressures.
Be sure that there is space in the worksheet for the technician to record their findings. A CMMS can capture and store these figures digitally, allowing for future analysis.
Documentation at a tactical level will capture the results of tasks completed in an area over a defined period. It will aggregate results to indicate progress against the maintenance plan.
At the strategic level, documentation will roll up all precision maintenance activities into a scorecard that allows program governance, and indicates progress toward the strategic objectives.
The financial benefits of precision maintenance
Reducing task variability and applying standardized best practices to maintenance tasks will help you fine-tune your maintenance programs. As a result, you should see a decrease in the number of task-induced failures and a more reliable machinery that operates within design parameters.
These improvements easily translate into improved production due to reduced downtime, with fewer out-of-specification products rolling out of production.
The end result is an improvement in revenue — with the main drivers behind it being greater on-specification production, reductions in maintenance costs because of fewer breakdowns, and a more streamlined and efficient maintenance schedule.
Improved revenues and reduced costs provide a meaningful improvement to company EBITDA. Capital budgets also get affected in the process, with the main contributors being the improvements in equipment lifecycles, amortizations in equipment costs over a longer production period, and delayed capital spending for machine replacements.
A list of benefits that are hard to pass over.
Traditional maintenance strategies focus on correctly scheduling the tasks necessary to maintain equipment operation and prevent unplanned breakdowns.
However, that is only one-side of the maintenance equation. You may have the best maintenance program, but if task acquittal is not optimal, you’re leaving money on the table.
Precision maintenance targets the other side of the equation. It ensures that, alongside good timing, completed maintenance work follows a high standard.
If you want to find out more about different maintenance strategies, methods, and best practices, keep browsing our maintenance blog.