FOCUS ON TECHNOLOGY
Coating Conveyor Pulleys for Protection and Longevity Peter Morgan Rhino Linings Australasia PTY LTD, Queensland – Australia
A
pmorgan@rhinolinings.com.au
ustralia’s resources and agricultural industries are significant
arranged in a shallow ‘V’ configuration so that centre of the belt is
components of the country’s strong economy. In particular,
lower than the edges thus reducing the likelihood of material falling
minerals and grains are commodities that earn many millions of
from the moving belt. On long conveyors there are often many
dollars of export income every year. Iron ore, bauxite, coal and grain
powered drive pulleys spaced along the belt’s length, interspersed
are transported by ship to overseas markets, but to get the material
between the many idler pulleys which move material from a loading
to the ship they are all transported at some stage by conveyor belt
point to the end of the conveyor. Conveyor capacity is determined
(ref. Opening Photo).
by the belt speed, width and the angle of the belt.
A continuous belt is just one of many types of conveyor systems. A belt conveyor system consists of two or more pulleys or drums with a loop of a material of some kind—rubber, polyester, wire mesh— that rotates about them. Depending on the length of the conveyor belt, one or more of the pulleys may be powered so that the belt and the material on it move forward. A powered pulley is called a drive pulley, while an unpowered pulley is called an idler pulley. There are two main types of industrial conveyors: those in general material handling such as ones used to move boxes or components inside a factory and for bulk material handling such as those used to transport large volumes of resources and agricultural materials, such as grain, salt, coal, ore, sand, overburden and more. The enormous conveyors and their supporting infrastructure represent many millions of dollars of investment by companies over many years so they need to be protected as much as possible. Massive stresses and strains are placed on the equipment being used when moving many thousands of tonnes of a material every hour along a conveyor belt system. These forces are in constant play at mine sites, bulk handling facilities and shipping terminals where material is moved from trucks and trains via in-loading circuits to stockpiles and then to ships via out-loading circuits. The longest single loop belt in the world is associated with a bauxite mine in Western Australia where a 31-kilometre-long continuous belt feeds a separate 20-kilometre belt to transport ore through the Darling Ranges to the Worsley Alumina refinery. This is an unusual conveyor, but bulk-handling facilities regularly have long conveyors, especially if there is no deep-water harbour on the coast and loading structures have to be built a long way offshore. As an example, the loading conveyor at Port Hedland in Western Australia is more than three kilometres long. Rollers that support, guide and move a conveyor are usually
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