Bowman Additive Production recently launched its latest innovation; its patent pending 3D printed split bearing cage, Rollertrain™ and it has already been nominated as a finalist at the prestigious annual TCT Awards in the Industrial Product Application category.
A game-changing design
Bowman AP and Midlands based bearings company John Handley Bearings (JHB) teamed up this year to design a brand-new range of cylindrical split roller bearings; the JHB Split Bearing, which will be launched later this year. The bearing cage is one of nine components within the split bearing however it is by far the most complex part to manufacture and has a significant impact on bearing performance.
Using engineering grade “printable” nylon (PA11) Bowman AP have developed a design that allows much closer spacing of the rolling elements compared to the “cap and body” cage designs, creating enough additional space around the roller track to incorporate up to 45% more rollers than existing products. It is these additional rollers that allow the load to spread over a higher number of rolling elements. This creates a 30-40% higher load capacity and extends the life of the cage by a factor of 3. The reduction in space required between the rollers is achieved through the complexity of geometry only available through 3D printing; it would not be possible using traditional injection moulding.
Jacob Turner, head of additive production at Bowman AP, explains “the cage design integrates a number of complex forms, which means that additive manufacturing is the only manufacturing method capable of bringing this concept to reality in an economically viable way. Combining this production method with Bowman’s experience and expertise in the bearings industry is a formula for success in the split bearing market”.
As well as increased life and capacity, the fitting time for Rollertrain cages is slashed by up to 50% as the design features a unique interlocking method which eliminates the requirement for clips or pins which are common on traditional cages.
Rollertrain cages have a comparable manufacturing cost to traditional parts, but the added value comes in the fact that they offer vastly increased performance benefits and significantly increased longevity. These benefits are only achieved through the use of additive manufacturing.
To injection mould a single range of 24 standard cages similar to Rollertrain bearing cages, the tooling costs alone would be in the region of £1 million – when you take into consideration the design errors and tweaks required to the tooling, the costs would rise still further. This is not to mention the design compromises that you would need to make to even allow moulding to be possible.
The JHB Split Bearing
The new JHB Split Bearing, due to be launched in October, was designed around the Rollertrain bearing cages and, for the very first time in the history of split bearings, can accommodate axial and radial loads independently. This is a capability that has not been possible before now and allows for the first time the calculation of an axial L10 bearing life. Due to the design and material of the Rollertrain bearing cage, the JHB Split Bearing has an increased radial and axial capacity of up to 70% and 1000% higher than any other split bearing in the world.
The new split bearing is set to disrupt the split bearings market this autumn and it is in no small part thanks to the durability and innovation of Bowman AP and its 3D printed Rollertrain bearing cage.