16 Dec Extending shredder service life
Shredding and removing deleterious materials can place extensive pressure on the machine itself, meaning the right componentry is needed to support the task.
Fortunately, innovations in productivity have continued to offer the recycling sector higher throughputs at a lower operating cost.
For shredding applications, a high performance spherical roller bearing is no different, paving the way for precise, repeatable motions and reliable extended operations.
While the basic functionality of today’s spherical roller bearings is similar to that introduced in the 1950s, suppliers such as Timken® have tirelessly worked towards continuous improvements and upgrades.
As an overarching strategy, Timken® has worked towards the core principles of greater load-carrying capacity, reduced operating temperature and extended service life.
Depending on the size of the shredder and application, Timken® offer a range of spherical roller bearings to support an after-market solution or product replacement. It offers a range of solutions, including pulp and paper, power transmission, metals, cement/aggregates and other applications.
Hardened steel cages, for example, work to deliver greater fatigue strength and protection against shock and acceleration loads. The steel cage comprises a unique slotted design that allows increased contaminant purging and lube flow, supporting lower temperatures and longer operating life. Rollers are guided by cage pockets, as opposed to a centre ring, which eliminates a friction point, resulting in four to 10 per cent less rotational torque and five degrees Celsius lower operating temperatures.
In designing high-performance bearings, Timken® has expanded its offering to suit the challenging needs of various sectors. One of its strengths as a supplier is offering both hardened steel cages and brass cages, while maintaining an acute awareness of the intricacies of each customer application. Its full line-up of spherical roller bearings includes coverage of all common sizes, from a small (25mm to 240mm), mid-size (240mm to 440mm) and large bore (>440mm).
“If you’re looking for a replacement shredder bearing, Timken® has a number of advantages,” explains Tony Tormey, CBC Australia Product Manager – Industrial Bearings.
Timken® spherical roller shredder bearings by design have lower operating temperatures to extend bearing life. By running 5°C cooler, on average, than the competition, the bearings can increase lubricant life which can mean nine per cent more bearing life.
Lower temperatures reduce the oxidation and deterioration of oils, greases and films and extend lubrication, thereby extending bearing service life. Additionally, this reduces friction and allows the bearing to turn and reduce torque.
Tormey says extra strength is important to reducing downtime, as some recycling plants could be running 24 hours a day, seven days a week. He says that Timken® spherical roller bearings offer higher load ratings that create a significant advantage over standard bearings, giving rise to less fatigue and placing less stress on the bearings.
Heavier loads may not only help operators take on more materials, but offer a variety of benefits. High performance can mean an increase in bearing service life, which allows operators to downsize other component selections while maintaining current levels of systems performance. For example, this might allow a metal recycler to increase its power density, leading to greater throughputs and longer system life.
Longer rollers also result in four to eight per cent higher load ratings or 14 to 29 per cent longer predicted bearing life. With higher load ratings, operators can carry heavier loads, thus improving productivity.
In shredding applications for example, Timken® recommends brass cages to handle the extreme operating environment. Brass cages offer extra strength and durability in the most unrelenting conditions allowing for high gravitational forces, shock loads and minimal lubrication.
New surface finishing techniques on the roller and raceway surfaces further enhance the benefits of greater durability and cooler operation. Importantly, the result reduces operating costs and extends the life of one’s shredder.
A practical example was observed when a Belgian Pellet Mill installed Timken® spherical roller bearings at its site, reporting a fivefold increase in bearing life and operating temperatures 5 °C – 8 °C cooler than the competition. The end result led to fewer maintenance cycles and greater uptime – demonstrating the importance of choosing the right technology to fit the task.