Ann: Production Update, page-35

I would agree to an extent with your comment. Yes, the crusher is a relatively simple unit in terms of purpose and mechanics. Plus, it doesn't have any chemistry involve... In saying that, i note that there are 2 types of crushers, the Jaw (which you defined) and the cone (secondary crusher). The update did not specify which amongst these became the problem child... They have not provided detail on what causes it too... A very common one is when motor power shoots up unexpectedly, and it can be caused by a lot of factors. A change in ore feed characteristics is only one but very minor...

In saying the above, defect elimination strategies should be in place to methodically investigate the cause. It would normally start with the sparkies working their magic around motors and PLCs, whilst maintenance team also make sure vital components are healthy (normally bushings and lube system checks). Although simplistic in nature, these activities involve massive amount of downtime (24-48 hrs minimum to complete) and rectification would follow. It is a good strategy to coincide and bring the mill shutdown forward. This proves to me that our operations peepz do really understand and experienced in operating a processing plant. So hats down to them.

If at a point in time the feed is to blame and there's less flexibility to change it, then i expect site will stock up on critical consumables and have a quick dispatch team to mitigate downtime risk, up until a new blend is being fed.