Noise level impacted by many factors
Safeguarding the environment is more important than ever before. SBMI, Swedish Aggregates Producers Association, has already demonstrated its interest by making a video about Metso’s Lokotrack Urban. The video is available on Abbema’s website. A sequence from the video showing the urban-friendly mobile crushing plant was shown at SBMI’s trade association meeting last spring, and Micael Larsson, a salesperson at Metso, says that after the SBMI meeting, he received several calls from customers who are interested in receiving more information about the crusher.
Crushing operations and their noise levels are naturally regulated. “Each municipality handles its own environmental permits, and the administrators here in Mjölby and Västervik, where our Lokotrack Urban has been in operation, have been very positive,” says Benth. “There are different rules for different times of the day as well as for the distance of the noise, but I am familiar with environmental permits and the related problems since I specifically worked with noise issues for so many years,” continues Benth.
From health and safety perspective, ear protection is generally required from 85 decibels. With Lokotrack Urban, the protection distance drops by up to 60%, from 23–25 meters to 9–11 meters. It is important to remember, however, that process noise is highly dependent on process parameters such as feed material, feed size, crusher setting and ambient temperature. Actual values may vary depending on operation conditions and other equipment used on the site.
Ad hoc jobs and plans for secondary crushing plant
“We have chosen to work on an ad hoc basis, which means we take contracting jobs that arise. Short notice works well for us. Rock materials and end products vary depending on the client. Consequently, having a mobile plant is a necessity, and it is a major advantage if we can crush rock in densely populated areas,” Benth explains.
“If everything goes according to plan, the next machine from Metso will be a secondary crushing plant. The model of greatest interest right now is Lokotrack LT220D, but it will also have to maintain a low noise level,” says Benth decisively. “Metso offers many solutions for noise level control during crushing; using rubber lining on the side conveyors and conveyor belts is just one example,” says Micael Larsson.
Abbema – a growing family-run business
Abbema is purely a family-run business with 16 employees. Sales are over EUR 3 million a year, and 900,000 metric tons of rock are crushed a year on contract. The company has been in operation since 2005 and it has 30 machine units in its fleet, including excavators, loaders, crushing plants, sorting plants and trucks.
Abbema’s field of activity includes southern Sweden as a whole, from Stockholm and southwards. The jobs they accept comprise either pure crushing work on contract or machinery leasing, with or without an operator. One important issue for Abbema is to ensure that its employees, who are spread out over a large area, are happy and feel a sense of fellowship with one another. “There is a shortage of workers in the industry, but people are actually standing in line to work for us, which is extremely gratifying,” says Benth.
*Metso Outotec was formed July 1, 2020 when Metso and Outotec merged into one company. This case study has been written prior to the merger under the old company name.