When it comes to performance in punishing environments, the Timken® Spherical Roller Bearing Solid-Block Housed Units are as good as gold. Which was certainly the case when Michael Greelish had these units installed in a Queensland gold mine.
“These unitised housings have multiple features that make them a great choice for conveying applications in the mines and quarry sector,” says the National Segment Manager for Mines, Quarries and Resources at CBC Australia. “In the case of the gold mine, we began using them on their tail drums due to failures from contamination with their previous standard bearings. The Timken units have been so successful that they’ve now installed them on all the head and gravity take up pulleys.”
The Solid-Block Housed Units are literally solid-blocks of steel that have been designed to eliminate the risk of bearing contamination.
“These units are completely sealed off and come pre-assembled – unlike standard bearings which are supplied in separate components, the bearing, housing and sleeve is all included,” Michael explains. “With standard bearings, if you need to install or have to replace them, you need to remove all the componentry, and on mining or quarry sites, that means you’ve got maintenance staff trying to fit them on conveyors in difficult conditions. All it takes is one small gust of wind and the dust blows in and contaminates the bearing while you’re trying to fit it.”
The Timken® Spherical Roller Bearing Solid-Block Housed Units remove this risk.
“With this product, it is entirely unitised,” Michael enthuses. “You open up the box and it’s ready to go, fully enclosed, and it’s just as simple as sliding the whole unit onto the shaft, locking the collar and it’s fitted.”
This means installation can be an easy and quick process if maintenance staff have been properly trained on how the bearing works.
“To fit standard bearings, you have to understand the technique and you’ll also need special tools such as feeler gauges,” Michael expounds. “These are used to measure the clearances, and basically when fitting the bearings, the person needs to keep tightening the nut in order for it to take more and more of that clearance out and get to the optimum running clearance. But with Solid-Block arrangement it’s all set at the factory for you.”
Importantly, the Timken® Spherical Roller Bearing Solid-Block Housed Units have an extended inner ring which separates the seals from the shaft.
“The inner ring is extended and the seals all run on that inner ring, whereas with standard bearings the seals will run on the shaft causing wear to the shaft,” Michael says. “Once the shaft is worn you have to replace it. But with these units because the seal is separated by the inner ring, you’ll never get shaft wear.”
Additional covers have also been utilised to help eliminate contamination from not only the environment but from the maintenance staff who wash them down with high pressure washers.
“The unit has triple lip seals in it, providing extra protection. Because as is the case with most conveyors, product is constantly falling off and collecting at the bottom of the conveyor, causing build up,” he elaborates. “While some people may shovel up the product and remove it, the preferred way is to hose it off with a fire hose. Standard bearings won’t cope well with that kind of water pressure, they’ll deteriorate very quickly. But these Timken ones are made to withstand this kind of pressure and the multiple sealing layers protect the bearings from water ingress.”
To summarise, Michael iterates the value in CBC’s service and expertise.
“We are the exclusive distributors of these Timken® Spherical Roller Bearing Solid-Block Housed Units, but more importantly, we have the in-house engineering capabilities and expertise to advise our customers on the best solutions for their conveyor applications – as was the situation with the gold mine. We invite our customers to come to us with any enquiries and we’ll problem solve to find the right solution.”