Controlling conveyor system safety, efficiency
Although the policy is generally not explicitly stated by companies, the low-bid process is usually an implied rule that is baked into a company’s culture.
It encourages bidders to follow a belt conveyor design methodology that is based on getting the maximum load on the conveyor belt and the minimum compliance with regulations using the lowest price materials, components and manufacturing processes available.
But when companies buy on price, the benefits are often short-lived and costs increase over time, eventually resulting in losses. In contrast, when purchases are made based on lowest long-term cost, benefits usually continue to accrue and costs are lower, resulting in a net savings over time.
Design hierarchy
Rather than meeting minimum compliance standards, conveyor systems should exceed all code, safety and regulatory requirements using global best practices.
By designing systems to minimize risk and the escape and accumulation of fugitive material, workplaces are made safer and equipment is easier to maintain.
Life cycle costing should play into all component decisions. Buying on life cycle cost and anticipating the future use of problem-solving components in the basic configuration of the conveyor provides improved safety and access, without increasing the structural steel requirements or significantly increasing the overall price. It also raises the possibility for easier system upgrades in the future.
Best practices
An assortment of control methods can be implemented to elevate safety around conveyors, but each method delivers a different level of effectiveness. Chart: Martin Engineering
Installing or providing for maintenance-minded solutions in the loading zone can greatly improve safety and reduce man-hours and downtime. These components include slide-in and slide-out idlers, impact cradles and support cradles.
On larger conveyors, maintenance aids such as overhead monorails or jib cranes assist in the movement and replacement of components.
Designers should also ensure adequate access to utilities – typically electricity and compressed air – to facilitate maintenance and performance. Next-generation conveyor designs may even feature a specially-engineered idler capped with an independent power generator that uses the conveyor’s movement to generate power for an array of autonomous equipment.
Dust, spillage and belt tracking are top concerns for safety professionals. Field tests show that enlarged skirtboards and engineered settling zones promote dust settling and reduce fugitive material. Curved loading and discharge chutes control the cargo for centered placement and reduced turbulence. As the load is centered on the belt, guides ensure even travel through the take-up to promote consistent belt tracking.
Any transfer point is prone to buildup and clogging under the right conditions, be it ambient humidity, material wetness, volume or surface grade. Flow aids such as vibrators or air cannons on chutes can sustain material movement, improve equipment life and reduce the safety hazards associated with manually clearing clogs.
Conclusion
Engineering safer conveyors is a long-term strategy. Although design absorbs less than 10 percent of the total budget of a project, additional upfront engineering and applying a life cycle-cost methodology to the selection and purchase of conveyor components proves beneficial.
By encouraging the use of controls at the planning stage, as well as the design hierarchy at the design stage, systems will likely meet the demands of modern production and safety regulations, with a longer operational life, fewer stoppages and a lower cost of operation.
Information for this article courtesy of Martin Engineering.
Featured photo: P&Q Staff
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