Steel manufacturing companies play a significant role within the South-African economy, not only by providing much needed jobs but also by being responsible for the manufacturing of material to be used in various parts of the construction, mining and manufacturing industry.
Grinding Techniques, a Tyrolit Swarovski Company, locally manufactures a variety of products under the brand name Andor for roll grinding used in the refurbishment of rolls in steel mills. From non-reinforced cut-off wheels used to cut steel samples prior to sanding with (NCH) No Centre Hole sanding discs, to cleaning of the surface in order for the metallurgy of the materials to be analysed all the way to the roll grinding wheels in the grinding shops. Whether you need abrasives for laboratory work, or roll grinding shops, we offer a complete package to cater for all your abrasive requirements.
Due to the continuous use of rolls to their limit in the production line, an ever-high demand is placed in terms of wear resistance and surface structure of the rolls to promote increase in life and usability. Roll grinding shops within steel plants in particular require high quality grinding wheels to grind and prepare the rolls for use and re-use after refurbishment. Whether focusing on cold or hot mills, it is important to note that each mill presents their own challenge when it comes to machining rolls.
Different rolls are used in the process from work rolls to back up rolls and these all have different profiles ranging from flat, CVC or Crown shaped. With new developments in the materials used for roll grinding such HSS, ICDP and forged steels various materials are now presented with a higher percentage chrome content for wear properties, and the advent of fully automated grinding machines, it is now of utmost importance to use reliable, consistent high-quality grinding wheels.
Hot mills require wheels offering fast stock removal rates and high performance, where surface finish tends to be less important. These rolls can range in diameters from 600mm to 800mm and with lengths ranging from 1 600mm to 3 400mm. In strip- and-plate mills, these diameters can go up to 915mm. Due to their extremely high stock removal rates, grit sizes ranging from 30 to 46 are normally preferred.
Cold mills on the other hand don’t have the same amount of material to be removed, but surface finish plays an important role. The work rolls in cold mills range in diameters from 300mm to 700mm and come with lengths up to 2 500mm. Grits sized between 46 and 150 will be preferred, as a finer grit is required to ensure a better surface finish.
Back up rolls in both hot and cold mills provide the necessary support and pressure to the work rolls and are larger in diameter going up to 1 600mm. Usually made of cast and forged steels with a chromium composition of two to five per cent, they are not ground as frequently as work rolls but have more material to be removed – in some cases material of up to 2mm.
Common problems experienced in roll grinding shops such as grinding chatter, traverse marks and bruising can be eliminated when partnering with a manufacturer that understands the quality demands within the industry, and produce wheels of only the highest standards. Grinding Techniques’ research and development centre regularly test and review products to ensure that grinding wheels produced conform and exceed the required standards, and that optimum results, longevity and value are evident when using our products.
Since 1981, we have been a trusted precision wheel supplier to steel mills. Our years of expertise and the latest cutting-edge technology allow us to combine high quality grains and proven bonding systems to manufacture wheels with exceptional stock removal rates, cooler cuts and longevity.
Part of the Tyrolit group since 2014, we are also able to supply specialised Tyrolit grinding wheels specifically manufactured for wire rolling mills. As these mills make use of grooved tungsten carbide rolls, they have a diverse range of wheel designs with specific profiles. As these profiles get worn quite quickly, they need to be regularly ground. Metal bond is the wheel of choice due to its high-profile holding properties for this complex application. With the CSS Wire roll range of super abrasives made in either metal, resin bond or electroplated, you will get both longevity and high stock removal with quality that never disappoints.
Apart from manufacturing and supplying precision grinding wheels, we also carry a range of dressing wheels to dress the wheels back to its original profile, which can be tailor-made with regards to sizes used on different machines.
Grinding Techniques is able to offer a complete abrasive solution with products to suit various applications. With constant innovation, development and research, we have been the preferred precision partner for decades. Let us help you keep the rollers rolling. Contact our precision business development team for more information on customised specifications and sizes to suit your requirements.