ARTICLE
Moving materials with a sustainable focus
Products like low-friction bearings can extend the life of conveyors and lifts and help to boost sustainability in the material handling sector, says Jerome Pommereul, Global Business Engineer at SKF.
The climate meeting in Paris proved that politicians are capable of coming to agreement on important issues. While they can be commended for their diplomatic skills, the hard work of implementing environmental targets will largely be down to industry.
SKF’ s Director of Corporate Sustainability, Rob Jenkinson, recently said that industry will need to“ roll up its sleeves and plot a way forward” in putting these commitments into practice. This needs to begin straight away, by investing in lower-carbon technologies and addressing specific sustainability needs.
The material handling sector encompasses everything from elevators in skyscrapers, cranes, light conveyors( like baggage handling lines) and conveyors in mines. Each part of the industry is very different, but has similar underlying sustainability concerns – such as boosting energy efficiency, extending service life and lubricant disposal.
Grease disposal
At one time, lubrication grease was simply disposed of but now it must be recycled. This, however, is not so easy at achieve. For this reason, there is a concerted effort to cut the use of grease in applications such as lifts, conveyor pulleys and cranes. Less grease means less disposal, which ultimately means less pollution.
One solution is to use bearings that do not need re-lubrication. In bearings with solid oil the lubricating oil leaves the oil saturated polymer material onto the bearing raceways. The part is then lubricated for life – which has the added advantage of cutting the need for maintenance operations.
In the heavy conveyors application, another popular way to solve the problem is to use a‘ three barriers’ solution. The solution consists of: a housing with a seal, a sealed bearing, and grease filled in the space between the bearing and the housing seal. The solution has environmental benefits, since the use of grease is significantly lower, because you no longer need to purge the bearing clean with grease. The bearing itself needs small quantities of grease to function. Furthermore, the bearing life is significantly improved because it is working in a protected and clean environment. In a conveyor Jerome Pommereul pulley this means that the Global Business Engineer life of the bearing system is
SKF longer or equal to the lagging on the pulley thus no longer a bottle neck.
Added efficiency
A far more pressing concern is energy efficiency – as it is for many sectors. Elevator manufacturer KONE estimates that up to 10 % of a building’ s energy consumption comes from the elevators, which makes it a key target for efficiency gains. There are already ways of clawing back some of this energy, through regenerative drives for example, or through traffic analysis optimizing the flow of people and number of elevators.
The move towards more sustainable and energy efficient products in lifts and elevators is partly accounted for by the strict LEED certification required for new building. This informs everything from building materials to construction methods. Regarding lifts, customers can specify the type of system they want and there is a definite trend in that they are increasingly demanding ones with higher standards of efficiency.
A third – and crucial – element of sustainability is to extend the working life of a product and its components. Every time
20 Global MDA Journal may 2018