Root Cause Analysis Report – 20 JULY 2020

INDISOL – LUBRICATION ASSET MANAGEMENT SOLUTIONS

1/ RCA Background

A telephone call from the Maintenance Supervisor of a large plant, identified that it was suspected an incorrect grease had been applied to several bearings earlier in the day under routine maintenance activity on kiln fan bearings. From questioning and discussion, we verified the suspicions were correct. It was agreed INDISOL would go to site next morning to assist with cleaning bearings and to train maintenance staff on correct practises to ensure failure risk was minimal is not 0%.

To form the basis of the RCA we were able to confirm.

• The PM was prepared day before task was undertaken
• The grease type on PM was incorrect but this was not identified by Fitter / Apprentice Assistant / planner
• The apprentice was tasked with organising new bearings, consumables (grease) and tools for task.
• The Fitter and Apprentice saw no reason to question grease type as they had not performed this work before.
• Take 5 was correctly undertaken and plant shut down for safe maintenance work to be done.
• Senior Planner checked and signed task off to be done.

Incompatible Greases

• The bearings are normally packed and re-lubed with a based on a perfluorinated polyether oil (PFPE) and polytetrafluoroethylene (PTFE), NLGI 2 grease
• In this case a grease based on ester oil, synthetic hydrocarbon oil and mineral oil and a barium complex soap, NLGI 2 was packed into bearing on top of old grease.
• The grease manufacturer was contacted to verify that greases were NOT COMPATABILE to confirm our deductions on the two technologies

Operation of Plant and Fan bearings

• The plant was shut down to negate risk and damage to equipment and left to cool overnight so we could gain access in morning
• No damaged had been done at this stage so it was determined cleaning and repacking bearings would be most appropriate course of action

2. Extent of Findings

Base on principle of 6 “R” in lubrication we have evaluated each of the “R” s to establish where the PM systems failed and have established following.

• Right Application – it was clear the application on PM was 100% correct and the Kiln Plant Fan bearings have been maintained over past 20 years at least, so no confusion here on what was being lubricated and which bearings were being changed out.
• Right Lubricant – Again what is a well understood norm for the lubricant to be used in this application among maintenance team was clear when examined and the same grease has been used by site for number years successfully.
  • However, there are 2 greases from same brand and packaging is similar for both grease cartridges.
  • Site have colour coded grease guns for visual inspection to avoid confusion and this was introduced more than 5 years ago and is well understood.
  • Incorrect selection of grease resulted in CROSS CONTAMINATION at varied levels in 3 bearings inspected and further 8 which had to be repacked due to CROSS CONTAMINATION of incorrect grease.
  • The grease specified on PM was incorrect and would normally not have been confused. This was cause of failing.
• Right Quantity – The PM clearly specified amount to be regreased and this was applied
• Right Quality – The application has unique equipment allocated for the task and no foreign equipment was used or applied other than incorrect grease cartridges were applied.
• Right Timing – PM dictates regrease timing and this was applied correctly – bearings are regreased ever 10 weeks and this works well for site
• Right People – Fortunately, the Apprentice after having completed the task approached Lube technician and spoke to him on grease and PM. This isolated and exposed the flaw in the PM and fact incorrect grease was applied. This was then communicated to maintenance Supervisor who immediately acted and had plant shut down while RCA was started. This avoided damage of any kind and allowed for error to be remedied. PEOPLE make a difference and a Culture of Care is vital to run successful planned maintenance, and it is evident this worked for the site and remedial action was undertaken immediately

1.2 Inspection of bearings and findings

Sample details	Sample Condition	Commentary	Urgent Action	Priority
Kiln 3	3 bearings Inspected and Re-packed
Bearing 1		Bearing had been packed with correct grease as per normal practise. Visual inspection indicates correct grease in cartridge more by accident and not design The fact equipment is dedicated for the plant PM activity is a strength if correct grease is in grease gun. Fortunately, correct cartridge left over from previous PM meant no issue was created in this bearing Grease texture is as new and colour as new No unexpected bleeding of grease noted NO CROSS CONTAMINATION OCCURRED to perfluorinated polyether oil (PFPE) and polytetrafluoroethylene (PTFE)	Nil action – close bearing and monitor after starting up and in few weeks for condition.	Nil issues noted and NO CROSS CONTAMINATION OCCURED
Bearing 2		Bearing two the grease gun had run dry and cartridges were changed. Clearly the barium Complex grease had been added causing CROSS CONTAMINATION with incorrect grease added Even though the grease only worked a few hours it is visibly clear texture had softened The perfluorinated polyether oil (PFPE) and polytetrafluoroethylene (PTFE) grease had been mixed with grease based on ester oil, synthetic hydrocarbon oil and mineral oil and a barium complex soap We note visible wetness from grease as it starts to bleed and form lumpy texture at base of bearing housing.	Bearing and bearing housing cleaned of old mixed grease. New fresh correct grease type was forced through bearing and on exit scrapped clean to ensure nil cross contaminated grease remained Bearing packed fully with new grease and housing filled to approx. 50%. Bearing sealed and closed and to be monitored over next period until ready for regreasing in 10 weeks This bearing was used as a training exercise for Fitters & Apprentices. On Job Training	Priority 1 Immediate action taken and bearing cleaned and repacked with correct grease Extra grease ordered in for same day delivery to allow other bearings to be packed as this process consumes excess amounts of grease.
Bearing 2		This bearing had been packed with 100% ester oil, synthetic hydrocarbon oil and mineral oil and a barium complex soap grease designed for high speed spindles The cross contamination came from grease in bearing and housing not cleaned out before regreasing as per normal practise for site. The grease was showing very quickly early signs of decay as two soap mixed. Bottom of housing had visible oil pool bleeding out of thickener. Dark blotches were visible in mixture and texture was changing after few hours of work Working grease between finger gave impression of sifter grease and not anything like NLGI 2	Bearing and bearing housing cleaned of old mixed grease. New fresh correct grease type was forced through bearing and on exit scrapped clean to ensure nil cross contaminated grease remained Bearing packed fully with new grease and housing filled to approx. 50%. Bearing sealed and closed and to be monitored over next period until ready for regreasing in 10 weeks This bearing was used as a training exercise for Fitters & Apprentices. On Job Training	Priority 1 Immediate action taken and bearing cleaned and repacked with correct grease Extra grease ordered in for same day delivery to allow other bearings to be packed as this process consumes excess amounts of grease.

2/ Extent of Findings and Recommendations

• It was extremely fortunate the Apprentice had a discussion on what he had done and noted with the Lubrication Technician.
• The fact they took the matter to a Supervisor immediately is indicative of a “CULTURE OF CARE” and should be promoted
• The prompt action taken by Supervisor to have plant shut down and start RCA is as it should be – do not delay
• The quick action to undertake RCA and report lead to immediate action of opening bearings
• The BEST PRACTISE applied to clean out contaminated bearings and repacking was world class
• ON JOB TRAINING and corrective action to promote awareness of consequence was immediate and positive.
• The loss in production was minimised against catastrophic failure of KILN FAN BEARINGS which could have resulted in excessive down time and extreme costs.
• The PM Structure Trees must be reviewed each time a PM is issued, and any corrections addressed immediately.
• As was in this case Senior staff should QC each critical PM to ensure all is correct
• Ideally skilled fitters should be allocated sensitive tasks such as these and they should be trained prior to undertaking
• Transfer of Knowledge is vital for a sound LUBRICATION ASSET MANAGEMTN SYSTEM
• Grease GUN MUST HAVE both Colour Coding and GREASE TYPE NAME clearly indicated to avoid errors such as this was
• QA system although informal in this case we cause of finding error and averting major plant damage. This should eb a formalised debriefing system to act as Check and balance.
• Training of maintenance staff in lubrication is VITAL and needs to be ongoing – even repetitive training to ensure all are informed
  • More critical is they learn to trust self-instinct and visual inspection
  • On colour alone they could have identified error immediately
• The learning opportunity in this case was immense as we had from inspection 3 bearings each faced with varied issues to consider
• Bearing 1 – Correctly regreased with previous cartridge so nil action was required. Correct grease applied
• Bearing 2 – Started to regrease with 1 grease type and then applied new cartridge and cross contamination
  • Grease started to shown signs of decay and degradation and would have failed inside 24 hours
  • Issue fully incompatible grease types
• Bearing 3 – small amount cross contamination but totally incorrect grease applied (high speed spindle grease not designed for extremely high temperature operation.
  • would have seen critical failure in under 12 hours as it was already bleeding. Issue incorrect grease applied