Corus Northern Engineering Services (CNES) is working with mining company Cleveland Potash to repair and refurbish gearbox casings and crusher rolls. According to CNES, this increases the service life of the gearboxes and helps eliminate breakdowns.
Cleveland Potash, a business unit of ICL Fertilizers, produces and supplies potash fertilisers and operates the UK’s only potash mine, from which it produces approximately one million tonnes of potash for fertilisers and around half a million tonnes of salt each year.
CNES’ work for Cleveland Potash includes weld reclamation of crusher rolls and refurbishment of large gearbox casings. At the potash mine, the six-tonne gearboxes drive cutting machines that cut away more than one million tonnes of rock each campaign from the face of the mine. Because of the harsh, corrosive working environment in the mines, the Auger gearboxes last for around two years before they need a complete overhaul. CNES carries out between three and four overhauls each year.
The gear casings are sent to CNES’ Teesside workshops as an empty shell, stripped of their component parts. CNES then shot blasts the casings and all working surfaces, the alignment and condition of the bearing housings is checked, and then a full inspection report submitted to Cleveland Potash. This report includes specifications on how CNES intends to reclaim the casings to the original dimensions.
CNES also carries out weld reclamation work on crusher rolls, which have a value of around €150,000 euros per pair. These crusher rolls are used to fine grind the salt and potash. CNES claims its weld reclamation process saved the company around 60 per cent of the cost of purchasing a brand new pair of rolls.”
Weld reclamation and metallurgical experts at Corus developed a specific welding procedure for Cleveland Potash’s crusher rolls. The weld reclamation machine at Scunthorpe operates continuously on the rollers for 365 hours, depositing a special 120mm thick hardened layer onto the rollers. The rollers undergo an intermediate stress relieving operation halfway through the welding process.