Long service life in the production of wooden pallets with lubrication-free linear bearings

• What was needed: linear guide in drive and handling units of pallet production systems
• Requirements: Resistance to chips, dust, moisture and resin, resistant to dynamic movements, vibrations and alternating loads
• Sector: Wood industry
• Success for the customer: Compared to conventional ball bearings and recirculating ball bearing guides, Krenzer achieves significantly longer service lives with dry-running drylin® linear guides. In combination with hardened steel shafts, the housing bearings work precisely and maintenance-free even under unfavourable ambient conditions.

Components in pallet production systems are exposed to particular loads. These include wood chips and dust, moisture and resin. On the other hand, the high dynamics of many drives with 50,000 strokes per day. This applies, for example, to the handling units of the nailing station. Here, the linear guides have to withstand alternating loads in a dusty environment because the moving ends attached to the axis move up and down when they remove a board from the magazine. Added to this are the continuous vibrations caused by nailing.

The designers were dissatisfied with conventional bearings such as ball bearings and recirculating ball bearing guides, as they were unable to achieve a convincing service life.

Following tests with different types of bearings, drylin® linear bearings have proven to be the best solution. They achieve the longest service life of around three months. This may not seem like much at first. However, if you multiply 50,000 strokes by 90 days, the result is 4.5 million working cycles - even with dirt, high dynamics and alternating loads. The linear housings are equipped with sliding foils made of wear-resistant iglidur® J-plastic and require no external lubrication thanks to the incorporated solid lubricants. As a result, dirt does not accumulate on them, maintenance is not required and the guidance of the axis runs extremely precisely.

Krenzer is so convinced by the dry-running bearings that they are not only used on the removal units for the top boards from the magazine, but also for feeding and exact positioning of the top boards.