20 Mar Low-friction roller bearings keep machines working longer
Processes in building material manufacturing often involve high temperatures and critical stresses. Cement, tile and brick production processes require hammer mills to crush the aggregate material into smaller pieces and then vibrating screens to classify these crushed particles by size.
Similarly, chipping the wood that goes into plywood laminates involves putting huge logs of wood into chippers, before moving on to rolling and cutting the laminate sheets.
All of these processes produce high temperature and fatigue loads that are ultimately taken by the bearings in the machines.
Michael Grant, Regional General Manager at Timken®, says the ultimate success in long life of bearings operating within these extreme environments is determined by how well they perform under high temperature and vibration.
One product that performs exceptionally well in this regard is the Timken® spherical roller bearing.
“We call it the coolest bearing in the world, as it runs cooler than any other spherical roller under normal applications,” Grant says.
“The Timken® spherical roller bearing has been uniquely designed with features that reduce internal friction, allowing them to perform better in higher speed applications or to run cooler at the same speed.”
The specially designed hardened steel cage pockets guide the rollers, eliminating the need for a centre guide ring, which reduces friction in the bearing. This means the machines have the capacity to run at lower operational temperatures, or conversely have the capacity to run at higher speeds without worrying about the generation of excessive temperature in the bearings.
Another advantage of the Timken® spherical roller bearing is the face slots in the cage. This feature facilitates better lubricant flow through the bearing and makes it easier for contaminations to exit.
“The higher load bearing capacity due to increased roller size and the improved speed capacity make these the perfect spherical roller bearings where application speed and high temperature are involved. If you can run your bearing cooler, then your lubricant lasts longer, which then gives you a better outcome for the bearing life in the machine,” says Grant.
The Timken® spherical roller bearings are available with both steel and brass cage options. While the hardened steel cages provide very high-level wear and fatigue resistance, Grant says the brass cage options are well suited to those applications where extreme shock loads and vibration are involved.
“While we recommend the standard hardened steel cage spherical roller bearings for the majority of applications, the brass cage could provide a good solution in vibrating machines or where high gravitational forces and minimal lubrication is an issue. For example, Timken® offers specialised spherical roller bearings with brass cages for vibrating screen applications or where centrifugal forces from radial loads and high speed push the lubricant out of the bearing,” he explains.
CBC has had a long-standing relationship with Timken® and serves as an authorised distributor for the whole range of bearings and bearing components from the manufacturer. The engineering team of CBC works alongside the technical team from Timken to offer 24/7 services to customers from CBC’s branches available nationally across Australia.
Tony Tormey, CBC’s Product Manager for Industrial Bearings says CBC’s extensive knowledge of bearing products, combined with the engineering expertise of Timken® work together to ensure customers get the best outcomes from their machines.
“When a customer first signs up with CBC, a team of CBC specialists visit the customer’s plant to conduct a full survey of the equipment available to make sure they can provide them with the best service when needed. The site surveys are basically mapping the plants to understand what machines and components the client has on the site. We make note of all of the rotating equipment on the site and analyse the components of the rotating equipment,” he explains.
Customers can rely on the combined expertise of the CBC and Timken® team to resolve any issue, even sometimes before they occur, according to Grant.
“Sometimes the customers are not even aware of an existing problem within their plants. Of course, they do not have the same knowledge of the product as we have, and they are not familiar with potential issues that may arise. We advise the customer on how they can get more service life out of their machines. This might be, for example, by suggesting a different style of bearing or a different style of housing,” he explains.
The CBC-Timken engineering team use their expertise to offer advice, from how to fit the bearings correctly to the best lubrication practices to extend the bearings’ and machines’ service life.
“Over-lubrication can sometimes cause as much problem as under-lubrication; particularly when high speeds are involved. We look at all the ways that can help customers to get better outputs,” says Grant.
While the Timken® spherical roller bearings have in general terms been selected to achieve a design life in most machines of around 100,000 hours – translating roughly to about 10 years of continuous work – Grant says there are many parameters that determine the actual life of a component.
“The component life will be different for every machine, based on the environment and the speeds they operate in, as well as on how they are fitted and lubricated. There are so many variables that can change from plant from plant.
“We work hard to ensure that the customers get the best output and service life from their machines. And the unique features of the Timken® spherical roller bearing allows us to do that,” he concludes.