Rotate 150kg on a cent coin

Problem

Previously, metallic bearings were used in the hinge systems .  These require a relatively large installation space.  Another negative effect was that the bearings had a clearly noticeable breakaway torque. The whole thing was accompanied by a squeaking sound. 

Solution

Our material iglidur Q290 offers a very good coefficient of friction for this case and therefore also a smooth swinging of the door.  Another advantage here is that the bearings have a thinner wall thickness and require less space in the hinge system.  

The Belgian company has been developing innovative door systems for the Benelux countries under the name ANYWAYdoors since 1995, and started selling its products online to global B2B customers about a year ago. "We sell our revolving door hinges as build-it-yourself kits exclusively online via our website, where they can be configured to meet customer needs," says Rudi Dies, co-founder of PortaPivot. "This is how we combine our own product, engineering and experience in assembly and installation with that of our customers' local network, their expertise and their local suppliers." “
 
PortaPivot door systems have already won several prestigious awards in recent years, including the Reddot and the iF Design Award. In addition, they were honoured for the "Best Architectural Product" (AZ awards), the Muuuz International Award for design & innovation, the Archiproducts design award, the Iconic Award ("innovative interior") and the "Best Products Award" of the Architects newspaper.

In addition to the design aspect that enables doors equipped with Stealth Pivot hinges to do without door frames and to be pivoted 90 degrees in one direction or 180 or 360 degrees in both directions, the tactile and kinaesthetic sensation is a very special experience.   This requires much less effort to swing open and, despite the heavy weight of the door, makes easy movement possible.
 
In addition to adjustable gas pressure springs, the hinges contain two polymer bearings from the motion plastics specialist igus, which enable the smooth movement of the doors and safely support the glass panels weighing up to 150 kilograms. "These plain bearings are only very small components, but the most important in our doors," admits CEO Rudi Dries. "The performance of these bearings is remarkable." Before the door hinges were used with the igus plain bearings, they were thoroughly tested by Wood.be in a specialised Belgian test laboratory. "Our requirement was for the doors to complete 200,000 cycles with a 90° opening movement, and for the hinges to do the same without failure," recalls Rudi Dries. "In our in-house tests, we even proved that with the plain bearings from igus they can even withstand 248,000 cycles with 180° pivoting movements." “

Hinge system and the iglidur plain bearing used within compared to a one-cent coin

PortaPivot's aim was to make service interventions obsolete for its products. In addition to their low coefficient of friction and wear, the polymer bearings from igus have another major advantage - their freedom from maintenance. The plain bearings consist of a mixture of base polymers, fibres and fillers as well as solid lubricants. The latter are, as microscopic particles, embedded in millions of tiny chambers of the material. This is sufficient to adequately lubricate their immediate environment and eliminate the need for external lubricants such as oils and greases. This dry operation prevents dust or dirt from adhering to the bearing points; it also does not contaminate doors and floors with greasy lubricants.
 
"Plain bearings made of iglidur Q290 are now used in the hinges," explains Lars Butenschön, iglidur plain bearings Product Manager at igus. "This material was originally developed for applications in agricultural engineering and is designed for medium to high loads and abuse forces." "PortaPivot was pleased with this recommendation," remembers CEO Rudi Dries: "We are product developers and not engineers. For this reason we are always looking for partners who can provide reliable support and help find solutions. This always works very well with igus. “
 

From left to right: Wim Laporte, Area Sales Manager plain bearings igus Belgium; Koen Dries, PortaPivot; Lars Butenschön, igus Product Manager iglidur plain bearings

The special feature of the PortaPivot application and the main reason for switching to the tougher material is that the entire weight of the doors - up to 150 kilograms - rests entirely on the flange of the bearing. This is used in other applications usually only to hold the bearing in place and not to absorb the full force. Based on the load-bearing surface, this application results in a surface pressure of 20 MPa. Most iglidur materials withstand this pressure no problem. However, edge loads caused by the leverage effect of swinging the door, in conjunction with the load applied across the flange and the cylindrical portion of the bushing, additionally stress the material, which could cause the bearing flange to tear off. However, for over four years, PortaPivot's applications have not suffered any significant failure, demonstrating the reliability of the iglidur plain bearings from igus.
 
Metallic alternatives were used at the bearing points in older generations of door hinges. However, they required more installation space due to a greater bearing wall thickness and also created an unpleasant "stick-slip effect", by which a significant break-off was felt and a squeak was heard when the doors moved. Thanks to the iglidur plain bearings from igus, these problems are a thing of the past, and smooth movements of the heavy but very stylish doors are guaranteed even after years of use.

Hinge system of the revolving door with iglidur plain bearings