When it comes to maintenance management, sequencing allows teams to develop a synchronised schedule for multiple jobs for one equipment, which improves efficiency and productivity of the plant as a result.
Add Energy's Hossein Ghavimi shares three example scenarios of how sequencing can be carried out, as well as his fundamental rules around sequencing maintenance...
3 example scenarios
1. SUPERSEDE AND SUPPRESS:
- There is a three monthly oil level check job on an engine, as well as a yearly oil replacement
- When the yearly oil replacement is due, the three monthly oil level check will also be due
- The oil replacement job would supersede the oil level check job, as an oil level check would no longer be required if an oil replacement job is being carried out
- The oil replacement job work instructions would mention how to carry out the oil replacement but not mention anything about an oil level check
- Therefore the oil level check job would be suppressed and no work order generated whenever the oil replacement job is due.
2. SUPPRESS ONLY:
- There is a monthly visual inspection of a pump, as well as a three monthly function test
- When the three monthly function test is due, the monthly visual inspection will also be due
- The function test job would not supersede the visual inspection job, as carrying out a function test requires a visual inspection to also be carried out
- The function test job work instructions would mention how to carry out the function test and visual inspection
- The visual inspection job would be suppressed and no work order generated whenever the function test is due, but the visual inspection would be carried out as part of the function test job work instructions.
3. DO NOT SUPERSEDE OR SUPPRESS:
- There is a monthly vibration analysis of a motor as well as a three monthly function test
- When the three monthly function test is due, the monthly vibration analysis will also be due
- The function test job would not supersede the vibration analysis job, as carrying out a function test is different to vibration analysis, which will also need to be done
- The function test job work instructions would mention how to carry out the function test but would not mention anything about the vibration analysis
- The vibration analysis job would not be suppressed and the work order would be generated whenever the function test is due.
Tips and rules around sequencing maintenance:
"Controlling when jobs are and aren't generated and what the content of job work instructions should contain will result in an optimised maintenance program.
"I have a couple of fundamental rules I advise around sequencing maintenance:
- You can only sequence maintenance for jobs with frequencies that divide into each other, for example work that is done every 1, 3, 6, 12, 24 months. So jobs that are 1, 2 and 5 yearly can’t be set up in a sequence.
- For a suppress only scenario - if job 1 is being suppressed by job 2, it’s very important that job 2’s work instructions include job 1."