Modern Quarrying Q4 2019

WATER TANKS

Successful aggregate managers know multiple factors contribute to their profitability, from minimising their trucks’ cycle times to ensuring their crew’s safety. Even support equipment, such as water trucks, can’t escape their analysis – or at least they shouldn’t. By Josh Swank . AVOID TANKING RISKS

H ow equipment operators haul and apply water can significantly impact overall productivity and safety. Though water trucks appear basic in application and design, several factors have a significant impact on efficiency, from the challenges of water movement in the tank to the steel used in the tank’s construction. All of these factors impact uptime, maintenance, efficiency and safety. The key to a productive and safe solution lies within the truck’s water tank design. It’s hip to be square Rounded water tanks are the most common. They get the job done, but not without challenges. The tank’s curved sides raise the water’s centre of gravity, making the truck less stable when navigating haul roads. To mitigate the instability, operators often avoid filling their tanks completely. This means they need to refill more frequently, contributing to added downtime and increased fuel con- sumption as they backtrack to the water source.

Additionally, rounded tank designs contribute to water churning since there are no corners, edges, or obstruc- tions to slow the water’s momentum. This constant, and sometimes rapid, water movement poses a safety risk for the driver and people nearby since the water can shift the centre of gravity and cause the truck to become unstable. Alternatively, water tanks with square corners mini- mise churning and have a larger capacity by simply not rounding off the sides of the tank. They also maximise productivity and operator safety due to their box-shaped structure, water baffles and water metering systems. The design also lowers the unit’s overall centre of gravity, enhancing stability and allowing drivers to safely fill the tank to capacity. The box-shaped structure makes it pos- sible to haul about 20% more water than rounded tanks, resulting in considerable time and cost savings. For example, an operation may have three, 60-t water trucks with 57 000 l rounded tanks in its fleet. Each truck works eight hours per day and sprays about one load

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MODERN QUARRYING QUARTER 4 - 2019