|General properties||Unit||iglidur® Q290||Testing method|
|Max. moisture absorption at 23 °C / 50% r.h.||% weight||3,0||DIN 53495|
|Max. water absorption||% weight||9,3|
|Coefficient of surface friction, dynamic, against steel||µ||0,14 - 0,26|
|pv value, max. (dry)||MPa x m/s||0,70|
|Modulus of elasticity||MPa||3.074||DIN 53457|
|Flexural strength at 20 °C||MPa||97||DIN 53452|
|Recommended max. surface pressure (20 °C)||MPa||55|
|Shore-D hardness||80||DIN 53505|
Physical and thermal properties
|Max. long-term application temperature||°C||+140|
|Max. short-term application temperature||°C||+180|
|Lower application temperature||°C||-40|
|Heat conductivity||[W/m x K]||0,24||ASTM C 177|
|Coefficient of thermal expansion (at 23 °C)||[K-1 x 10-5]||7||DIN 53752|
|Specific contact resistance||Ωcm||> 1012||DIN IEC 93|
|Surface resistance||Ω||> 1012||DIN 53482|
iglidur® Q290 bearings do not have the highest static load capacity within the iglidur® product range, instead the material shows its strengths at moderate to high dynamic loads: outstanding service life is achieved for rugged pivoting applications, e.g. in agricultural or construction machinery, and especially on "soft" shafts, for both the shafts and bearings!
With increasing temperatures, the compressive strength of iglidur® Q290 plain bearings decreases. Diagram 02 illustrates this relationship. With the short-term permitted application temperature of +180 °C, the permitted
surface pressure is still more than 10 MPa. The recommended maximum
surface pressure is a mechanical material parameter. No conclusions regarding the tribological properties can be drawn from this.
Diagram 03 shows the elastic deformation of iglidur® Q290 at radial loads.
Typical applications for iglidur® Q290 bearings include mid to high-load pivoting movements at comparatively slow speeds. However, relatively high speeds are still attainable. The speeds shown in table 02 are threshold values for low bearing loads. They do not provide any indication of the wear resistance under these parameters.
The maximum long-term application temperature of +140 °C enables the use of iglidur® Q290 in, for example, typical applications in the agricultural, commercial vehicle or construction sectors. Starting at an operating temperature of +80 °C, an additional axial safeguard is necessary for the bearing, as a press fit alone is no longer sufficient.
Please note that a sliding surface with a rough surface finish will increase the friction. The coefficient of friction of iglidur® Q290 increases as the speed increases (Diagram 04). In contrast, the coefficient of friction drops continually with the radial load, as illustrated by Diagram 05.
|C. o. f. µ||0,15 - 0,23||0,09||0,04||0,04|
Generally, the use of hardened shafts is recommended for higher loads starting at approximately 10 MPa. This is, however, often not the case in practice, especially in connection with corrosion-resistant coating methods. Thus, the iglidur® Q290 material is very influential in such applications. Diagram 08 shows this very clearly in connection with galvanised shafts.
|Alcohol||+ to 0|
|Greases, oils without additives||+|
|Diluted acids||0 to -|
|Strong acids||+ to 0|
iglidur® Q290 plain bearings are radiation resistant up to a radioactive intensity of 3 x 102 Gy.
iglidur® Q290 bearings have good resistance
to UV rays and other weathering effects.
In a vacuum, any moisture content will outgas.
Applications under vacuum conditions are possible to a limited extent.
|Maximum moisture absorption|
|At +23 °C/50 % r.h.||3,0 % weight||Max. water absorption||9,3 % weight|
Under normal climatic conditions, the moisture absorption of iglidur® Q290 plain bearings is 3,0 % weight. The saturation limit in water is 9,3 % weight.
|to 3||0 - 0,025||+0,014 +0,054||0 +0,010|
|> 3 bis 6||0 - 0,030||+0,020 +0,068||0 +0,012|
|> 6 bis 10||0 - 0,036||+0,025 +0,083||0 +0,015|
|> 10 bis 18||0 - 0,043||+0,032 +0,102||0 +0,018|
|> 18 bis 30||0 - 0,052||+0,040 +0,124||0 +0,021|
|> 30 bis 50||0 - 0,062||+0,050 +0,150||0 +0,025|
iglidur® Q290 plain bearings are standard bearings for shafts with tolerance h (recommended minimum h9).
The bearings are designed to be pressed into a housing machined to a H7 tolerance. After the bearings are installed in a housing with nominal dimensions, their inner diameter automatically adjusts to the E10 tolerances. For particular dimensions the tolerance differs depending on the wall thickness (please see product range table).