Plastic bearings from igus help provide smooth and maintenance-free performance in hinges of pivot doors for an innovative and growing manufacturer in Belgium.
PortaPivot, which is known throughout the industry for its simple and stylish designs, uses igus’ iglide plastic bearings at the top and bottom of its products. The bearings, which are rated up to 150 kilograms (about 330 pounds), support the complete weight of the doors. The glass doors do not require traditional framing.
igus, the Germany-based manufacturer of motion plastics, runs its North American operations out of Providence, R.I.
PortaPivot has been developing innovative door systems under the name of ANYWAYdoors since 1995. The company initially focused on Belgium, the Netherlands and Luxembourg, and has been selling products on the global B2B market for about a year.
“We sell our pivot door hardware as self-assembly kits that can be purchased exclusively through our website, where they can be configured to meet the customer needs,’’ said Rudi Dries, 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 won several prestigious awards in recent years, including the Reddot and the iF design award. The company also won the “Best Architectural Product” (AZ awards), the Muuz International Award for design and innovation, the Archiproducts design award, the Iconic Award (“innovative interior”) and the “Best Products Award” from the Architects Newspaper.
Smooth movement guaranteed
PortaPivot doors with Stealth Pivot hinges can swing 90 degrees in one direction, or 180 or 360 degrees in both directions. “It’s not like glass doors in supermarkets, where you feel a great deal of resistance when you push them,’’ said Koen Dries, co-founder of the business and its sales and marketing director. “Since our doors are exclusively developed for indoor use, they do not have to be designed to withstand strong wind.”
As a consequence, the door requires less effort to swing open, and despite the heavy weight of the door, makes easy movement possible.
In addition to adjustable gas pressure swings, the hinges contain two plastic bearings from igus, which enable the smooth movement of the doors and safely support the glass panels weighing up to 150 kilograms.
“These plain bearings are very small components but are the most important in our doors,’’ Rudi Dries said. “It’s amazing to see what these bearings can do.”
Before the door hinges were used with igus plain bearings, they were thoroughly tested in a specialized Belgian test facility. “Our requirement was for the doors to complete at least 200,000 cycles with a 90° opening operation,’’ Dries said. “In our in-house tests, we proved that with the plain bearings from igus they can withstand 248,000 cycles with 180° pivoting movements.”
Maintenance-free over entire service life
PortaPivot’s aim was to make service interventions obsolete for all of its products. In addition to their low coefficient friction and wear, the igus bearings are also maintenance-free. They consist of a mixture of base polymers, fibers and fillers as well as solid lubricants. The lubricants are embedded in millions of tiny chambers as microscopic particles. They adequately lubricate the immediate environment and eliminate the need for external lubricants, such as oil and grease.
This dry operation prevents dust and dirt from adhering to the bearing points, and does not contaminate doors and floors with messy lubricants.
The bearing contains around 50 iglide materials for a wide range of applications. These include materials for high-temperature applications up to +250° Celsius (482° Fahrenheit) and others that are certified for use in food or railway technology. Plain bearings made with iglide G, an all-around material, were originally used in the door hinges of PortaPivot. During the course of product development, igus experts suggested a more durable material.
“Plain bearings made of iglide Q290 are now used in the hinges,’’ said Lars Butenschön, iglide pain 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.”
Rudi Dries remembers approving the recommendation. “We are product developers, and not engineers,’’ he said. “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.”
The primary reason PortaPivot designers chose the tougher material is that the weight of the doors rests entirely on the flange of the bearing. The material 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 iglide materials withstand this pressure easily. However, edge loads caused by the leverage effect of swinging the door, in conjunction with the load applied across the flange and cylindrical portion, add additional stress that could damage the bearing. However, in more than four years, PortaPivot’s applications have not suffered any significant failure, demonstrating the reliability and durability of the iglide bearings.
Metal alternatives were used in previous generations of door hinges. They required more installation space due to a greater bearing wall thickness, which created a “stick-slip effect.” The doors squeaked upon movement, and did not operate smoothly. The iglide plain bearings made those issues a thing of the past, allowing effortless and unrestricted movements on the heavy doors for years to come.