Why small slewing ring bearings might be better?
Small slewing ring bearings are better than big? In a world where the slogan “bigger is better” is commonly used in perhaps a slightly derogative way, igus® are going to show you how that is just a misconception when it comes to our products. Bigger is not always better!
Our slewing ring product group, or PRT range that is commonly known as, is used as ready-to-install solutions for all pivoting and turning tasks. Our newest addition to the family is the PRT-04. The arrival of this particular PRT has been welcomed with open arms. Not only is it 60% lighter with more than 50% space saving, it creates more options for the small slewing ring bearings to be involved in applications that previously may have been constrained with parameter restrictions.
Small slewing ring bearings, can they cope?
What we didn’t want was for the thinner PRT to be at a disadvantage when it came to weight capacity, so we did some research where we measured how much of the load capacity of the PRT-01 was realistically being used in the applications. It transpires, it was very rare that the 01 version slewing rings were being used to their full load capacity.
This gave us further inspiration to develop the 04 version into what it is today. Developing this product, we kept the same igus genius elements that we all recognise, with the maintenance-free polymer sliding elements, but now due to the height having been reduced by 50%, it allows even more design freedom than we previously had.
An important tip to remember:
The PRT is not symmetrical. The head ring of the PRT is very thin and therefore the screws holding all rings together don´t have a lot to hold onto. So, if you mount something on top of the PRT, it is imperative that the screws are long enough to go through the whole assembly to secure it.
PRT-01 versus PRT-04, which is best on the face of it?
Size options:
PRT-01 comes in 8 different sizes, whereas the PRT-04 currently only comes in 6. The PRT-01 ranges from a 20mm inner diameter up to the 300mm diameter, whereas the PRT-04 ranges from 50mm inner diameter up to the 300mm inner diameter. With the 04 version being brand new this is not an issue and if the demand is there, the range will inevitably expand. Of course, there are always opportunities to work with our customers on bespoke solutions to integrate features and reduce the component count.
Cost:
The PRT-04 is 25% cheaper than the PRT-01 based on a like- for- like size comparison. A no-brainer if you don’t need huge load capabilities.
Ease of assembly:
The PRT-04, with its new practical spacing ring, makes the installation nice and easy and this new design has no need for relief grooves or cut outs for the mating moving parts. The PRT-01 is also easily installed and has a wealth of accessories to work in conjunction with it, such as position stops, hand clamps and motor couplings. Both versions can be driven using a belt or spur gear profile for automated applications.
In conclusion, the design of these new small slewing ring bearings is perfect if you need to reduce cost, are restricted in regard to space and need a weight saving.
Yes, the PRT-01 has a greater size disparity range but this new “one size fits all” slewing ring delivers in all areas it needs to, so watch this baby grow.
For more blogs on the igus® PRT slewing ring bearings visit https://blog.igus.co.uk/?s=prt and learn about the adaptability of the PRT-04 here https://blog.igus.co.uk/the-adaptability-of-the-prt-04/
