A major factor in servicing material handling equipment is access to the mast. Most service managers acknowledge that accessibility theory and practice are very different; especially when engineers need to access the top of the mast - which can be some considerable height from the floor.
This worrying issue came to light when leading chain supplier FB Chain were working with one of their large customers on a project to develop best practice for roller chain lubrication. It became immediately apparent that there is a big problem with servicing chain rollers operating at the top of tall masts.
Peter Church FB Chain’s Managing director explains "we already make chain rollers and fit them with a number of different types of bearing solutions, however, they all need lubricating. We discussed this problem with one of our bearing suppliers and they showed us a new bearing material that we instantly knew could offer us a good solution to the ‘infrequent or no maintenance’ chain roller issue". This has since led FB to develop and market their new ‘Sealed-for-life’ chain roller.
The new FB ‘Sealed-for-life’ chain rollers, which remove the need for greasing, will not only increase service intervals but also minimize machine downtime. The new design also removes the need for costly cross drilled pivot pins with grease nipples that are necessary when using conventional chain pulleys.
The FB ‘Sealed-for-life’ pulley takes advantage of a new type of self-lubricating sintered bush. Traditionally bronze bushes have only been used in light duty applications but with the new material design they can now take more than 3 times the load. For example a standard wrapped bush will withstand a load of circa 150 N/mm² whereas the new material will withstand in excess of 500 N/mm². The intricate bearing design together with the addition of shaft sealing units also keeps the lubrication inside the chain roller and on the working surface.
These new FB ‘Sealed-for-life’ rollers have been extensively tested by one of FB’s major OEM customers and have survived over 60,000 arduous cycles on their test machine. The machine was lifting its maximum load (4 Tons) through the full range of its movements, angles and heights.
Following successful testing this materials handling OEM is now using them on all their new machine designs. They are also currently involved in ‘Reverse Engineering’ these new chain pulleys into all their existing designs as a cost efficient solution to achieving significant improvements in maintenance and operating performance compared with their standard pulleys fitted with roller bearings.