Food & Drink Processing & Packaging Issue 35 2021 | Page 56

Are your preventive maintenance routines fit for purpose ?

Reviewing your PM routines can reduce workloads and improve plant performance , a ‘ win-win ’ scenario . Michael Dixey and Pete Hibbs of GGR Associates explain how
Few people doubt the need for appropriate preventive maintenance . Who would be prepared to fly in an aircraft that had not been properly maintained ?
The key word here is appropriate . A significant percentage of preventive maintenance routines in the food and drink sector are inappropriate and can even be counter-productive .
Here are some typical shortcomings :
The PMs are based on manufacturers ’ recommendations . These do not take into account the equipment ’ s criticality , e . g . whether there is a stand-by unit or buffer stocks . They do not recognise 56 FDPP - www . fdpp . co . uk the equipment ’ s operating context , e . g . whether it operates single shift or 24 / 7 . They take no account of what is being handled and they ignore the environment , e . g . whether it is in a clean room or exposed to dirt and debris
Many of the PMs are time-based rather than condition-based . Time-based maintenance can be described as “ taking kit to pieces at regular intervals to see why it is still working ”. Conditionbased maintenance is often described as “ letting the equipment tell you when it needs to be maintained ”
Too little use is made of condition monitoring techniques such as vibration analysis , thermography , ultrasonic leak detection and oil analysis
Where condition monitoring is undertaken , it is carried out by specialist contractors . More often than not , this could be better done in-house . This can lead to significant cost savings , increased ownership and improved outcomes
Many PMs could be better carried out by operators rather than technicians - as part of Asset Care programmes . Typical tasks might include non-intrusive checks for wear , condition or leaks
Generic PMs where the same PM is used for a range of similar but not identical equipment . For example , all the conveyors have the same PMs although they vary in length , width , speed , drive motor / gearbox size , some are fixed speed and others are inverter driven , and some are horizontal and others are inclined
PMs which are not value-adding , as they cost more to carry out than they save by reducing failures .