In September 2018, TAKRAF won a service order for changing a pair of roller press roll bodies for an important Mauritanian customer.
HPGRs, also known as roller presses, are used in Mauritania for the processing of iron ore. A roller typically consists of a base body (shaft) to which a roll body in combination with a wear protection system is attached. The surface of the roll bodies is subject to heavy abrasion during operation, so that regular replacement of the roll bodies is necessary.
At the beginning of 2019, the pair of worn out rollers arrived at our workshop in Lauchhammer, Germany. Removing the worn out roll bodies is the first step in the reconditioning process. Based upon previous calculations, the roll bodies were detached from the shafts by means of inductive heating in cooperation with a specialized partner. The release of the roll bodies occurs due to the steep temperature gradient to the shaft surface and the resulting difference in the thermal expansion of the roll bodies to the shaft. Subsequently, the shafts were mechanically reworked, with the bearing seats being reconditioned using a flame spraying process.
After the machining of the delivered brand-new roll bodies, the shrinking on the reworked shafts followed. Again, in cooperation with our partner, the roll bodies were heated in a specific and defined manner until the inner diameter of the roll bodies opened beyond the outer dimension of the shaft due to thermal expansion. The shaft was inserted into the roll body to create a frictional connection after cooling. The wear protection, made up of numerous tungsten carbide studs, was then applied, with these studs being glued into the surface of the roll body using a special adhesive.
With the successful completion of this order, a significant reference for both the sale of TAKRAF roller presses and the service business has been achieved.
TAKRAF Group, through its established and well-known brands, TAKRAF and DELKOR, provides innovative technological solutions to the mining and associated industries. We leverage our experience, acquired over more than a century, to provide equipment, systems and services that best satisfy our clients’ mining, comminution, material handling, liquid/solid separation and beneficiation requirements. Owners and operators around the world trust our engineered solutions to lower the total cost of ownership and reduce environmental impact by improving efficiency with safe and reliable equipment. For sustainable solutions backed by expert service you can rely on TAKRAF Group. Visit us at www.takraf.com or send an e-mail to info@takraf.com.