Case Study: A Spares and Availability Programme for a 120-Machine Remote Fleet

Quick answer: A 120-machine remote fleet consolidated from seven chain configurations to three, then rebuilt its spares hierarchy around a forward-consumption forecast. Part availability rose from 61 to 98 percent, resupply distance fell 60 percent, and working capital in stock dropped 44 percent.

Availability problems in remote fleet operations are rarely spares problems in the sense that the part was not in the store. They are logistics problems wearing a spares costume: the part was available, but the distance between the warehouse and the machine was 340 kilometres of unmade road, and the machine was idle for six days while the part travelled.

This is the account of a programme for a 120-machine fleet operating across remote sites in a mining and exploration concession, and what it took to move part availability from 61% to 98%.

The customer's position

The operator ran 120 crawler machines across 14 sites, spread over roughly 11,000 square kilometres. The sites ranged from a well-serviced main camp with a full workshop to four exploration camps with a mechanic, a basic workshop, and a parts cage.

The reported situation was that undercarriage availability was the binding constraint on the fleet's productive hours, and specifically:

• Parts were ordered ad hoc, reactively, following breakdowns, at whatever price was available that week
• Each site held its own parts cage, with no standardisation between sites, and the cages were frequently full of parts that would not fit any machine on site
• Resupply was scheduled monthly by road, which meant a part ordered on day two of the month waited three weeks for the next convoy regardless of the machine's condition
• The operator had no way to forecast which parts would be needed, because consumption data was not being collected systematically

The analysis that reframed the problem

The first step was a consumption analysis across the previous 36 months. MAGEON reconstructed per-machine hours, per-part consumption, and per-failure data from the customer's maintenance records, and grouped the fleet's machines by the undercarriage components they used.

The finding was decisive. The fleet nominally comprised nine machine models from five manufacturers, but the undercarriage stock fell into only seven distinct chain configurations, and three of those accounted for 91% of consumption.

This is a common finding in fleet spares analysis. The apparent diversity at the machine level is much narrower at the component level, because a handful of chain sizes covers most of the industry.

It also meant that a rational spares programme required far fewer part numbers than the customer's stores held, and that the biggest available gain was not in buying more, but in reorganising what was already bought.

The three-part programme

Part one: standardise the chain to three configurations

Rather than carrying seven chain configurations, MAGEON and the operator's engineering team agreed to consolidate the fleet onto three, by changing the chain on the machines that could be converted, and by agreeing with the OEM suppliers on a standard chain for future machine purchases.

The conversion was done during scheduled component replacements, so it cost no additional machine downtime. The effect on the spares inventory was immediate and large: the number of distinct chain, roller, idler, sprocket, pin, and bushing part numbers fell by 62%.

Part two: a forward-consumption forecast instead of reactive ordering

Because consumption could now be predicted from hours and known wear rates, MAGEON built a rolling 12-month forecast for each part number, and reworked the resupply cycle around it.

Rather than a monthly convoy for everything, the programme established:

• Critical stock — items whose failure stops a machine, held at every site, sized on failure rate and resupply time
• Regional stock — held at two regional hubs, sized on demand across the sites they serve
• Expedite-on-demand — for non-standard parts, with a committed 15-working-day lead time from MAGEON's verified drawing archive, and a contracted air-freight option for genuine emergencies

One of the most valuable operational changes was simply moving the resupply from a fixed monthly cycle to a fortnightly one for critical items, and aligning it with the site's shift-change schedule so that parts arrived when there were people to fit them.

Part three: the parts cage rebuilt around data

Each site's cage was re-specified with a physical layout driven by the forecast, and — more importantly — with a physical enforcement of the standard. Cages were relabelled by machine model and chain configuration, so a mechanic picking a part was picking from a bay that could only contain parts that fit a machine on that site.

The customer described the previous situation as "every cage was a museum of parts that belonged to a machine we no longer had". The rebuild eliminated that entirely, and released capital tied up in unusable stock.

Results over 24 months

The availability figure is the one the operations director tracks, and 98% against 61% transformed the site's response to a breakdown from an emergency into a routine work order.

What the customer says was the surprise

It was not the availability figure. It was the working capital.

The customer had assumed that improving availability meant holding more stock. It meant holding less, in fewer places, chosen from data, and reordering on a schedule driven by consumption rather than by a fixed convoy date. The spares programme released capital the customer had not known was tied up, and that capital was redeployed into a second tranche of machines that had been deferred on capital grounds.

The general lesson is worth stating plainly: most fleet availability problems are inventory organisation problems wearing a logistics costume, and the fix is rarely buying more.

What this programme required from the customer

It is worth being honest about that, because the work was not unilateral:

• 36 months of maintenance records made available for analysis
• Agreement to convert machines during scheduled component replacement, rather than resisting the change
• Discipline in following the new reorder points, which was uncomfortable for the first two quarters when the buffer looked thin
• A physical rebuild of each site's parts cage, which is unglamorous work

No spares programme succeeds without those five things. MAGEON's contribution was the analysis, the standardisation proposal, the supply commitments, and the technical support to the site teams; the rest was the customer's own operation, and they did it well.

MAGEON product lines and how they map to this topic

The engineering principles in this article apply across the full MAGEON product range. Each custom undercarriage order starts from one of four chassis families, and the selection logic above determines which one fits your machine.

Whether you are specifying a custom undercarriage from first principles, comparing a customized steel track chassis against a customized rubber track chassis, or reviewing the service life of a customized steel track undercarriage in abrasive service, MAGEON can size, engineer and support the build. Every crawler undercarriage project begins with your machine's weight distribution, working conditions and interface drawing, and the quotation is backed by a written calculation. Contact our engineering team with your host model, working conditions and mounting interface, and we will respond with a configuration recommendation within one working day.