Double protection against dirt: felt seals for iglidur plain bearings

The new sealing concept for additional protection of igus plain bearings and shafts in agricultural equipment and construction machinery.

Sand, dirt and abrasive dust can have an adverse effect on plain bearings and shafts. For this reason, igus has developed an additional method of protection for its lubrication-free iglidur plain bearing – seals made of felt. By placing on the flange of the bearing, it prevents the ingress of dirt and reduce maintenance intervals and machine failures.

Plain bearings in agricultural equipment and construction machines are often exposed to wind, weather and dirt. This makes things difficult, especially for bearings made of metal as they have to be greased regularly to prevent the bearing from failing, corroding or being destroyed due to dirt at the bearing point. Users therefore may opt for iglidur plain bearings made of tribo-polymers as they have built-in solid lubricants and, as a result, eliminates the need for external lubrication. In addition, they are corrosion-free and insensitive to dirt. In order to additionally protect the bearings against the ingress of sand and dirt, igus has further developed felt seals for its iglidur plain bearings.

Stefan Loockmann-Rittich, head of business unit for iglidur bearings at igus, explained: “The advantage of felt is that, when dirt tries to enter, it is compressed in the felt structure. This prevents sand and dirt from getting to the bearing and shaft.

“Thanks to the use of iglidur plain bearings with the seals, the user can achieve savings in respect of maintenance intervals, lubricants and costs. At the same time, no polluting lubricating grease is released into the environment.”

Even if initial lubrication is required, the felt ensures that the grease stays on the bearing and does not become contaminated, igus stressed.

The felt seal has a sealing capability in the company’s 3,800 sqm test laboratory. The company reported that an iglidur plain bearing sealed with felt under sand achieved a service life that was 50 times longer than an iglidur plain bearing without a seal, and the shaft also demonstrated “considerably fewer signs of wear with a felt seal than without”.

The igus product range also includes sealing rings made of polymer for applications where plain bearings are exposed to various media. The polymer seals off the plain bearing in such a way that liquid, such as aggressive cleaning agents, is unable to reach the bearing or components behind it. Igus supplies the polymer sealing rings made of an all-round material for all igus flanged bearings, and made of an FDA-compliant material for use in the food industry.