Mining Mirror May 2017 - Page 24

Mining in focus It’s all in the detail Going back to basics is the best way of getting more mileage out of screening decks and panels, writes Leon Louw. M ining entrepreneurs are faced with a deluge of options and challenges when devel- oping an operation from scratch. The same can be said of an established mine that intends increasing produc- tivity and needs to upgrade existing infrastructure and equipment. The final decision on which methods to use or what equipment to install will determine the financial viability and long-term sustainability of the project. Contrary to popular belief, vibrating screens and feeders play an important role in the mining cycle. Higher commodity prices will lead to increased profit margins if the mine is adequately prepared. If it is not, ineffective equipment is the one variable that can sabotage the success of any business. It is important to use the best tools for the job. But what do managers, owners, and operators need to look out for — not only now but also in the future — when they acquire, install, upgrade, or replace screening and vibrating machines? [22] MINING MIRROR MAY 2017 According to Kenny Mayhew-Ridgers, chief operating officer at Johannesburg- based Kwatani vibrating equipment solutions (previously known as Joest Kwatani), it is important to determine the type of material that will be processed before the vibrating screening and associated equipment are purchased or replaced. “You should know, for example, how sticky or flowable the material will be. That knowledge determines what type of screening media should be used,” says Mayhew-Ridgers. When a company installs a new vibrating screening or feeding machine, it is important to consider the size of the machine, together with the size and the state of the building where it is earmarked to be housed. There should be enough space to install and remove the machine comfortably from the building. “This can be tricky,” says Mayhew-Ridgers. It is not only the size of the machine that is important; the building should be spacious enough to allow for a crane to operate in when installing and removing the vibrating equipment. One of the biggest challenges when replacing old equipment, however, is removing the surrounding pipes, wiring, and electric cables that, like a network of arteries, often engulf the machines. “The piping networks around some of these old machines are a nightmare and it is a major challenge getting the machine out,” says Mayhew-Ridgers. Looking at the finer details It is the small detail that really makes a difference when installing new vibrating equipment. The surface area on which the isolators are fixed should be perfectly level, reflecting the exact conditions under which the vibrating equipment was assembled and tested. Traditional isolators include coil springs, rubber buffers, or torsional springs. The isolators are spring-like pedestals onto which the vibrating screens are fitted. Its core function is to