How do you compress a shutdown from 36 hours to 11, expand its scope nearly a hundredfold, and at the same time stretch the shutdown interval from two weeks to sixteen?

Sounds too good to be true?

In a greenfield project, everything is new: equipment, people, and ways of working. This operation was no exception. A handful of expats had been brought in to transfer knowledge, but otherwise nearly all of the ~300 employees were first-timers in the mining industry. And it showed in almost everything.

Part 1 – Evolution

A few months into the first steady production days, during a morning meeting, the shift supervisor casually remarked that the mill feed spout was leaking badly. The maintenance team listened with genuine curiosity; apart from their manager, this was new territory for them.

A lively discussion followed. It escalated quickly, and in the end the concentrator’s deputy manager declared:

“Well then, we’ll have a shutdown today.”

Everyone nodded. Consensus was achieved in seconds, driven by a single voice.

Production personnel began thinking about shutdown procedures, some about controlled ramp-downs, others perhaps even about lockout-tagout. Maintenance scrambled to piece together spare parts, manpower, and a rough scope. Corridor conversations organically expanded the worklist: the cyclone feed pump, leaking hydrostatic bearing oil lines on the grinding mill, and screen panel replacements.

The decision had been made dynamically within a 20-minute morning discussion. Shutdown actions began immediately at 09:20.

By around 13:00, the first tool finally touched the equipment. Efficient. Only four hours from decision to execution. A highly dynamic environment, the superintendent thought to himself.

Scaffolding was erected around a hydraulic line. It appeared that piping meters had run short during construction as the line had been built from two pieces instead of one. No problem: off came the NPT-threaded fittings, and work began.

A short pipe segment and only one new fitting were found from leftover project materials. Since the second fitting wasn’t leaking, it was deemed “good enough” to reuse.

The job was completed. The system was pressurized.

The oil pressure barely had time to approach nominal levels before the reused fitting began leaking and this time worse than the one that had just been fixed.

What a success.

The cyclone feed pump didn’t fare much better. The casing had been removed, but the impeller clung to the shaft like a disease to its host.

The day had started at 07:00, and the technicians were running out of legal working hours. Naturally, no evening shift had been arranged. Work was halted mid-task, to be resumed the next morning.

The impeller finally came loose aided by fresh eyes, and perhaps turning it in the right direction helped too.

All in all, these few tasks took over 36 hours.

No one sang songs of glory about this shutdown. It left behind no legacy, except one quiet, persistent thought:

There must be a better way.

Four Years Later:

At the same mine, with essentially the same team, a shutdown was underway once again.

This time, it was a different story.

The shutdown strategy had been defined a year earlier during the budgeting process, anchored firmly in wear profiles of critical equipment. Planning was deliberate. Execution was disciplined.

Maintenance started work at 07:00 sharp.

A scope nearly one hundred times larger was completed in approximately 10.5 hours.

After the shutdown, the plant didn’t resemble a battlefield. It looked like what it was meant to be: a clean, efficient production facility.

While the scope had grown exponentially, the duration had been compressed to roughly one-third. At the same time, the shutdown interval had been extended to 16 weeks. A remarkable achievement given the ore characteristics: exceptionally hard (22.6 kWh/t) and abrasive (Ai 0.34), placing significant wear demands on equipment.