Maintenance 101: Getting ahead of breakdowns
If you have been following the past three articles of Maintenance 101, you’ll know we’ve been exploring the basics of world-class maintenance (if you missed them, you can find them online at www.mromagazine.com).
April 1, 2012 | By Peter Phillips
If you have been following the past three articles of Maintenance 101, you’ll know we’ve been exploring the basics of world-class maintenance (if you missed them, you can find them online at www.mromagazine.com).
So far we have covered the first three stages of the process, which include:
1. Preparing for professional maintenance
2. Equipment evaluation and deterioration
3. Breakdown analysis.
In this issue, we’re going to examine Stage 4: How to establish a professional maintenance program on equipment.
The purpose of this stage is to develop the following steps:
1. Pre-maintenance checks on equipment
2. Shutdown and start-up processes
3. A PM structure
4. An equipment spare parts system
5. PM procedures and maintenance instructions
6. Maintenance schedules
7. A work order system
8. PM compliance and outcome monitoring.
Let’s look at each of these steps.
Step 1: Pre-maintenance performance checks simply measure the current state of the equipment. Reviewing equipment availability and mean time between failures, and performing a breakdown analysis, will reveal where preventive maintenance (PM) maintenance activities need to be improved.
Although all equipment requires a degree of preventive maintenance, more critical and complex equipment needs complete PM procedures.
The pre-maintenance study of the equipment will help to develop effective PM instructions and the frequency of maintenance intervals. The type of frequency will also need to be determined. Will it be time-based by date, by hours of operation or by number of equipment cycles?
Step 2: Shutdown and start-up processes and procedures go hand in hand. They include the actual steps to shut down the equipment and the operator’s responsibilities to ensure the equipment is prepared for maintenance. Procedures to clear the equipment of product and the shutdown sequences must be documented. They must include lockout procedures to ensure there is zero-state energy on all equipment and also for every maintenance activity.
When the maintenance is completed, Hand Back procedures must be followed so production personnel can safely and systematically start up the equipment to resume production.
Step 3: Prepare a PM structure. The PM structure is developed into a process flow diagram that sets out a path that supports the whole PM system. Every step in the flow must be addressed to build a successful PM program. Do not skip any steps in the process (see Figure 1: PM Structure Process Flow).
Step 4: Add equipment to the Spare Part System. In order to carry out effective maintenance, the spare parts that will be needed to carry out preventive maintenance must be identified. You need to create equipment ledgers and link spare parts to the machines. A CMMS will be your best friend when it comes to documenting and linking equipment material lists. Parts needed for PMs can then be organized prior to the maintenance date.
Step 5: Build PM procedures and instructions. The content of periodic maintenance procedures should include:
• Part replacements
• Lubrication
• Inspections
• Settings and adjustments
• Safety and environmental testing
• Calibrations
• Overhauls.
Parts replacements may include time-based replacement of some equipment components. For parts that are difficult to reach and inspect, it may be more cost-effective to simply replace the part on a scheduled time frame. Breakdown or service request analysis on equipment records can also identify parts that fail on a regular frequency. It may be feasible to replace these parts on a PM program before they fail.
Lubrication is said to be the single largest reason as to why equipment components fail. Lubrication schedules, using the correct lubricant and the quantity to apply, are critical to the life cycle of your equipment and its components.
Inspections: Detailed instructions of what to inspect on the equipment can be developed by reviewing manufacturer’s recommendations, doing breakdown analysis, and relying on the experience of your maintenance personnel.
The secret here is to make the checklist specific. Using gauge readings and physical measurements requires craftspeople to engage themselves in the inspection. Meaningful data will be recorded and better maintenance decisions will be made. It is well-known that simple checklists are too easily abused.
Setting and adjustments: Recording settings and adjustments can become the basis for setting standards and optimizing the maintenance frequency. Frequent adjustments indicate wear and the need for component replacement.
Problems during start-ups can sometimes be linked to adjustments carried out during PM. Craftspeople must understand that these changes may indicate an underlying problem that must be investigated.
Safety and environmental testing: It is important to verify that equipment is operating according to specifications. These tests and measurements are often associated with safety, the environment or regulatory requirements. Therefore, equipment safety devices, lifting equipment and portable appliances need to be inspected to protect personnel and equipment.
Some safety and environmental inspections will require documentation showing recorded results, the date of inspection, remedial action if required and the signature of the tester. Some regulatory inspections may require special qualifications or external specialists.
Calibration procedures check the accuracy of critical indicators and measurement devices. These instruments can control parameters that affect the specifications of a product or its emissions levels.
Calibrations may also require specific documents where adjustments are recorded, signed and dated, and may also require third-party services.
If you are using a CMMS, testing and calibration documents can be automatically printed with the PM work order.
Overhauls: During shutdowns, complex equipment is often rebuilt and restored to optimal running condition. These overhauls normally take several days to perform and can only be done during shutdown periods. Overhauls require both inspection and replacement of parts. Specific instructions and rebuild procedures will be needed to complete the job correctly.
There is no room for error in these overhauls, as breakdown of these critical machines cannot be tolerated during normal production.
Step 6: Create a maintenance schedule based on the following points:
• The frequency the maintenance task should be based upon.
• Equipment records, both planned and unplanned. Refer to your CMMS to help determine appropriate maintenance intervals.
• Craftsman investigation and visits to the equipment (using findings from Steps 1 and 2).
• Manufacturer’s recommendations.
Access to the equipment and craftsman availability are also two important issues. Therefore, it is necessary to group PM tasks into manageable slots, when production will release the equipment. It is also a good idea to look at vacation schedules. During certain times of the year, you may have fewer maintenance labour hours to perform all the PM work. The schedule needs to reflect these periods.
Step 7: Implement a Work Order System. Based on labour and equipment availability, it will take considerable work to plan and introduce a PM calendar. A CMMS will manage the schedule and it will generate work orders on the set frequency you have developed.
As we have discussed in previous articles in this magazine, you must have a work order flow to ensure everybody knows their responsibilities in the work order process.
Step 8: Monitor PM compliance and outcomes. Here we need to monitor PM conformance, such as on-time completion, whether a job is completed or not, and the percentage of completion.
You also need to introduce post-maintenance performance reviews.
Examine the equipment performance between PM visits – breakdowns, minor stoppages, quality problems and environmental issues. If the equipment is still having frequent breakdowns, are items that are missing from the PM causing the failures? Identify these items and update the PM procedures or instructions.
Examine the results of each individual PM task. If certain inspection items are found to be ok or within specifications on every PM, then decrease the frequency of that PM or item.
Don’t forget to advertise your results. Effective preventive maintenance programs increase uptime and productivity. Create a Maintenance Results board and display graphs and PM findings and corrective actions.
Every company needs to work on their maintenance culture. They need to recognize the need for PM and that the vicious cycle of breakdown maintenance must be broken.
So there you have Step 4. We are halfway through our trek towards developing the basics for world-class maintenance. Next time, we’ll look at countermeasures against equipment weak points and ways to increase equipment life.
MRO
Peter Phillips of Trailwalk Holdings, a Canadian CMMS consulting and training company, can be reached at 902-798-3601 or by e-mail at peter@trailwalk.ca
To view the full layout of this article with images, as it originally appeared, see page 26 of the April 2012 issue. The digital edition of this issue can be found here:
