Swapping rolling bearings for plain bearings, keeps sanders in working order
A woodworking manufacturer used a commercial wood sander for fast sanding of large furniture. However, their sanding table would only successfully function for about a week before failing. This would lead to a costly cycle of replacing damaged parts and awaiting the next shut down. The manufacturer decided to take action and approached PBC Linear for a solution.
The wood sander station sat on a 180 lbs steel base and used high speed oscillating motion (1735 RPM) for a short, 4mm stroke. The oscillating mechanism is operated by two cam assemblies running with a roller bearing in between. As the system runs in short, reciprocating motion, the sanding mechanism is operated. This wood sander is under constant use by two labor shifts (1st and 2nd), 16 hours a day for six days a week until it breaks down.
For the roller bearing to function properly, precise alignment was crucial. The slightest misalignment resulted in grinding between the cam and roller bearing. High friction and heavy shock loads caused fretting on the system. In fact, shop employees commented the roller bearing would glow red from heat created by friction where the cam system made contact. Even when running under lubrication, misalignment, high temperatures (110°F) and grinding would persist and the system was unable to last a full week.
The PBC Linear solution
When PBC Linear stepped in, they immediately recognized the problem as a great application for their Simplicity® plane bearing technology. Simplicity plane bearing products handle up to 20x the load of a traditional rolling element bearing. The proven technology of their proprietary Frelon liner supports even disbursement of forces; while rolling element bearings provided limited point of contact and cannot effectively disburse heavy loads. Primarily utilized for linear applications, Simplicity products also excel in rotary and oscillating tasks. It is also ideal for dirty workshop environments, gliding through wood chips, dirt and grime without binding or additional maintenance.
For this particular application, PBC Linear designed an optimized bearing assembly that would rock along with the motion of the cam system—completely eliminating misalignment issues. Using an internal, periodic lubrication system to facilitate smooth oscillating motion for long-term operation, PBC Linear was able to extend the life of the system from one week to over a year of smooth, non-stop and maintenance-free performance.
Results / ROI
After the custom Simplicity assembly was installed, the wood sander realized immediate increase in life-time performance. The manufacturer also noted significant cost savings as a result of life improvement. Weekly replacement parts for the previous internal design amounted to $300.00, with $15,000.00 in annual cost savings! Overall, the wood manufacturer was more than pleased with the new Simplicity bearing assembly, as it provided enhanced system integration, quieter operation and overall cost saving for the wood sander.