Case Study – Magnetic Plug Program

Implementing a Magnetic Plug program for keeping machinery reliable and operating is vital to any company who doesn’t want to spend tens of thousands of dollars, not just on failed components, but also in lost production time.

magnetic plug inspectionsFor years Techenomics has worked with BMA Blackwater in Queensland, developing a weekly program and system of reporting that has saved them hundreds of hours in downtime and millions in dollars. Planned work can be actually be scheduled meaning they know they will have machines working when they are supposed to be working, rather than sitting in a workshop awaiting new parts.

Over the years Techenomics has come across a large number of cases where if magnetic plugs had gone unchecked it would have cost the company tens of thousands of dollars not just in failed components but also in lost production time. Instead the discovery of these contaminated plugs allow for the planners to schedule work to be carried out on the particular component which is illustrated at right.

As highlighted in the photo, this particular plug has quite a lot of sludge build up with some signs of fine metal in the sludge. With this type of occurrence a simple flush and refill of clean oil could solve the problem. If after the flush, the problem keeps occurring they need to look deeper into the problem. If it is just a build up of sludge from dirty oil then oil analysis is not going to be of much help which is why the Plug Inspections and the recommendations given are vital. Something that seems bad may very well turn out to be an easy cost effective solution. This is of course the lower end of the scale and failures can occur at any time.

Some of the findings on the plugs are simply a build up of sludge which comes from just topping up oil levels and not actually flushing the component out prior to refilling with new oil. Residue builds up at the bottom of the component and mixes back into the fresh oil, resulting in the fine metal getting into places where they continually scratch the surfaces of the internal components wearing them down unnecessarily causing other problems such as loss of tension or grip due to pits being created on the surfaces surface.

Some would think this a minor problem and write it off as wear and tear on components, though it is surprising how quickly these small problems can escalate and companies have major failures occurring causing downtime and loss of production time. All of this at the end of the day means money.

An example of how quickly things can wrong, even with weekly inspections on all mobile equipment, are highlighted in the following photos which are in monthly blocks.

The above images show that on the first monthly inspection there is a slight build up of sludge on the plug which has been marked as a B - in other words Techenomics need to continue to monitor it. The second Inspection shows the plug as being clean as when the Dozer has gone into the workshop for a service or other work, the oil has been drained and the plug wiped clean. This is how Techenomics Technicians found the plug. Moving onto the next inspection you will see how the build up has returned, but take notice of the location it appears. The Dozer has left the workshop and has been parked up on the deadline so has not travelled very far for the sludge to reappear which indicates that if the machine was sent back to work, within a week the build up would be quite substantial and could possibly have to return to the Workshop once again costing not only money but loss of production time.


The Next Illustration shows how much can build up on a weekly basis.

magnetic plug inspections

These plugs are checked by Techenomics weekly and are wiped completely clean after each inspection. The amount of metal and sludge that would be on this plug of no checks were carried out would be enormous.

There may be a new Drive ordered for this Dozer so until the arrival the company may be keeping this dozer working or it may be near the end of its working life. With Magnetic Plug Inspection reporting, the planners can keep an eye on the final drive and if necessary park the machine up until the new drive arrives.

Below is a couple of cases where it is evident failure is starting to begin in the space of a week between inspections.

As is illustrated in the images, in a course of a week the residue has built up on the plug and this plug now needs attention. If Techenomics weren’t carrying out weekly inspections, these plugs would normally only be removed by service personal in the field to top levels and would not be wiped clean. The only other time these plugs would be removed and checked is at a 500 hr inspection where the condition is written down on a service sheet, no photos taken or other records kept. Techenomics record information including hours, location and date and a photo of the plug is taken each week. Along with Techenomics Blue Oceans Program these serve as vital tools to predict failure or extend the life of the component.

More Extreme cases are illustrated below

The above inspection is from a Letourneau Loader, this has been an ongoing problem with nobody knowing the answer. The component has been pulled apart with no apparent wear on parts. One of the reasons this is happening may be because this is an electric drive loader and perhaps the wheels were not synchronised correctly or when tramming the loader over distances it was not designed to do. Currently a new drive for this machine is being built in the hope the problem will not occur again. Without Techenomics weekly inspections, this may have gone unnoticed until the Loader stopped working and the company loses money in unplanned loss of production, as opposed to scheduled service time.

Other examples found during Techenomics weekly Inspections:

The above images show a small piece of metal on the plug with residue on the outer. The small piece was actually a piece of bearing inside the component that was about to collapse. The Techenomics Technicians reported this and the machine was brought in for repair and sent back out to work. Gone unnoticed, the machine may have been stuck out in the field until such times as they were able to tow it into the workshop.

As you can see by the above photos, The Magnetic Plug Program conducted by Techenomics is a vital part of any Preventative Maintenance Program. The reports along with the photos and Blue Oceans analysis data collectively allow any planning office to schedule work on their machines to prevent failure in the field which not only saves cost but saves lost production time and is also a safety measure by not having a machine fail  when you least expect it to.

For further information please contact Sam Kurup, email: info@techenomics.com or visit www.techenomics.net