igubal® Frequently Asked Questions

1. What are the advantages of plastic components?

In the case of plastic components, the lightweight advantage and the lower price compared to comparable metal solutions are particularly noteworthy. In addition to the general specifications, every iglidur® bearing material has a number of special specifications that make it exceptionally suitable for specific applications and requirements. In addition, our products are lubrication-free and therefore maintenance-free.

2. Which material is right for me?

With just a few application data, pre-selection and service life calculation is already possible via our igubal® configurator. The large variety of materials is quickly culled, leaving behind only the suitable materials.

3. How can igubal® spherical bearings do without lubrication?

Due to the special structure of iglidur® materials, which are usually composed of a thermoplastic matrix, fibre reinforcements and so-called solid lubricants. The good wear and friction properties of the matrix or base material are additionally enhanced by the solid lubricants. During operation, there are always enough particles of solid lubricant on the surface of the bearing. Additional lubrication from the outside with grease or oil is usually not required or not useful.

4. Are plastic components just as strong as metal components?

All our products are closely examined in our test laboratory and even though we are convinced of the quality of our products, we are always amazed at how strong they really are. Even though we reach high loads in many areas, plastic components naturally also have their limits. Metallic components have an edge, especially at very high temperatures (above 250°C) or very heavy loads.

5. How is a plug gauge measurement carried out?

1.1 igus® demonstrates, among other things, by means of a plug gauge test, also known as a "go/no-go test", that our bearings meet specifications and function properly after installation.

First of all, the bearings are press-fitted in a test housing. It must be ensured that the bearings are undamaged when they are fitted. A housing chamfer is recommended - ideally 25 to 30 degrees. The use of an arbor press with a flat punch is also recommended in order to press-fit the bearing in the housing. This is the most efficient method of installation. It also ensures that the integrity of the bearing is preserved. If you use a hammer, for example, the bearing can jam when it is being installed.1.2 igus® recommends that an arbor press be used to press-fit a plain bearing.

The actual plug gauge test takes place after the bearing has been fitted. A "go" means that the plug falls through the bearing under its own weight, whereas a "no-go" means that the plug does not fall through the bearing or becomes stuck. The plug gauges are graduated in increments of 0.1mm so that it is possible to very precisely determine the dimension above which the respective plug becomes stuck.A plug gauge test is the most accurate quality check because the plug behaves like a shaft in a real-world application and mirrors the smallest cross section of the bearing. It is precisely this aspect that is usually decisive for the application. Plug gauge tests are especially suitable for plastic bearings because the irrelevant "points of unevenness" of the bearing caused by the injection moulding process are not taken into account. Once the bearing has been put to use, an ideal sliding surface is achieved during the running-in phase, in which the points of unevenness of the bearing and shaft are smoothed out.Other tests can be used to carry out a quality check on a bearing but problems can arise if these methods are applied to plastic bearings. In particular, the use of calipers should be avoided. Calipers should only be used for quick quality checks, depending on the level of accuracy desired. Depending on the pressure exerted by the caliper at the measuring point, the measurement can be falsified. For this reason, a plug gauge test is much more reliable.

The described test can also be carried out directly on a series-produced component, depending on its accessibility (in other words, not in a test housing specially made for this purpose).