Modern Mining May 2019

CRUSHING, SCREENING AND MILLING

allowing maintenance activities to be con- ducted more easily,” Gordon explains. The third machine is 3,6 m wide by 7,3 m long and this double deck vibrating screen will be positioned at the discharge end of a HPGR (high pressure grinding roll). It also has an inte- gral isolation frame. All screens are equipped with polyurethane panels on both the upper and lower decks with the screen media panel layout optimised to ensure screening efficiency. Another important engineering focus is to optimise screen designs wherever possible to allow for a high commonality of componen- try. This allows customers to reduce on site inventories reducing total cost of ownership. Examples in this case would include the exciter gearboxes and all structural members including cross beams, feed boxes, drives beams and back members, and springs. 

resident expertise and experience. It also has an established database of information on suc- cessful applications of FLSmidth screening technology. “During the engineering process, we make use of sophisticated software including finite element analysis,” he says. “Importantly, this is an integral in-house function at FLSmidth and is not outsourced to a third party.” The advantage of keeping all these activities in-house is that the engineer involved in the original data analysis and engineering of the screen is also involved in analysing the FAT data. In addition to the inherent insight this gives FLSmidth engineers, they also use the global database of installed screens to access valuable information on root cause failure anal- ysis and other analytical data. A recent order undergoing the FAT process at FLSmidth Delmas is for a copper-mining operation in Kazakhstan. The order comprises three vibrating screens, two of which are 3,6 m wide by 8,5 m in length and mounted on iso- lation frames. One of these screens will be installed in an existing SAG mill circuit on the mine, while the other is a standby unit. This is a retrofit application and because of the exist- ing plant’s support structure it was necessary to provide a screening system that incorporates an isolation frame. An innovative design concept was also applied, and the screens will be installed on rolling frames. “This eliminates the need to shutdown the plant when screen maintenance or repair is necessary as the complete screen can be rolled out and replaced by the standby screen, reducing unnecessary downtime and

Aerial view of the FLSmidth Supercenter in Delmas.

A SAG mill discharge vibrating screen on an isolation frame.

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May 2019  MODERN MINING  47