Avoid hurt to CGB
Recently, we got a complaints from a Chinese cement client saying that our CGB have quality problem.They said the breakage rate are rather high and many CGB surfaces witness severe hurt.
It’s weird as after 2018, we upgraded the formulation of our CGB, breakage rate had been successfully refrained under 0.3%. How come the severe breakage issue come back again?
After site investigation, we believe we found the result. It turns out the ball mill operation was not managed properly. According to our regulation,the CGB are not permitted to run in the ball mill while there’s no feeding. It not only cause hurt to the liners and ball mill shell,but also bring about breakage rate rise and surface damage extensively. Unfortunately, the operator of this ball mill didn’t comply with this regulation. There’s evidences suggest he didn’t stop the ball mill operation immediately when the feeding was cut and left the empty ball mill rotating for over 20 minutes........while more than 80MT of CGB were bumping and crashing to the mill shell and the liners........and it happened more than once.
Below photo show some the surface hurt of some sample CGB.
CGB as grinding media is very appropriate for grinding purpose. However, due to light weighted compared with traditional HC steel balls, it works inferior than steel balls for crushing and dashing.This is the reason why we normally only apply it to 2nd chamber or 3rd chamber,which take the advantage of its high grinding effectiveness. Meanwhile, with raw materials as alumina, this corundum property product has another flaw-brittleness.Although its hardness is higher than HC steel balls,we don’t recommend to use it for lump breaking function, so as to avoid hurt and thus reduce its life service.
Below is the photo of unused CGB.Ain’t they beautiful? As a high wear resistant product,we should know its property and put them into use properly.