Arrium Mining had been experiencing excessive wear in their cyclone spigots. The traditional rubber spigots had a service life of only 3-4 weeks. Ceramic spigots would certainly extend the service life by up to 8 times, however, due to large scats and the odd stray mill ball, ceramic was not an option. The metallurgists were looking for an alternate material that would improve the service life of the spigots and approached Keramos for advice.
Ceramic materials were considered too brittle for this application. Keramos considered the use of A05 chrome steel as a possible alternative spigot liner material. Keramos had successfully supplied A05 vortex finders to a mine site in Western Australia that had experienced similar issues. Chrome steel A05 provides exceptional wear resistance and the toughness to withstand impacts from scats and mill balls.
The worn A05 spigots were taken out of service after 8 weeks and it is estimated they would have offered a further 2 weeks service life.
A senior metallurgist had the following to report. “The service life out of our spigots has doubled as a result of moving from the standard rubber to the Cr alloy materials. With rubber, the service life was between 3 to 4 weeks, compared to 8 to 9 weeks with the Cr alloy material. Our shuts are at 4 week intervals, so the Cr alloy spigots are being taken out at 8 weekly intervals. This has been a good saving for us, thank you for your help with that”.
The Keramos A05 chrome steel spigots are changed out every 8 weeks, saving the customer on spares and labour costs, as well as maintaining performance.