iglidur® Q290 – material data

Diagram 02: Recommended maximum surface pressure as a function of temperature (55 MPa at +20 °C)
 
X = Temperature [°C]
Y = Load [MPa]

Diagram 03: Deformation under pressure load and temperatures
 
X = Load [MPa]
Y = Deformation [%]

Mechanical properties

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.

Maximum running speed

m/s	Rotating	Oscillating	Linear
Continuous	0,8	0,6	1
Short-term	2,0	1,4	2,0

Table 02: Maximum surface speeds

Permissible surface speeds

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.

Temperatures

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.

Diagram 04: Coefficients of friction as a function of the surface speed, p = 1 MPa
 
X = Surface speed [m/s]
Y = Coefficient of friction μ

Friction and wear

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.

iglidur® Q290	Dry	Greases	Oil	Water
C. o. f. µ	0,15 - 0,23	0,09	0,04	0,04

Table 04: Coefficients of friction for iglidur® Q290 against steel
(Ra = 1 µm, 50 HRC)

Diagram 06: Wear, rotating application with different shaft materials, p = 1 MPa, v = 0,3 m/s
 
X = Shaft material
Y = Wear [μm/km]
 
A = Aluminium, hard-anodised
B = Automatic screw steel
C = Cf53
D = Cf53, hard-chromed
E = HR carbon steel
F = 304 stainless steel
G = High grade steel

Shaft materials

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.

Medium	Resistance
Alcohol	+ to 0
Hydrocarbons	+
Greases, oils without additives	+
Fuels	+
Diluted acids	0 to -
Strong acids	+ to 0
Diluted alkalines	+
Strong alkalines	0

+ resistant      0 limited resistance      – not resistant
All information given at room temperature [+20 °C]
Table 05: Chemical resistance

Radiation resistance

iglidur® Q290 plain bearings are radiation resistant up to a radioactive intensity of 3 x 10² Gy.
 

UV resistance

iglidur® Q290 bearings have good resistance to UV rays and other weathering effects.
 

Vacuum

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

Table 06: Moisture absorption of iglidur® Q2

Moisture absorption

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.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® Q290 E10 [mm]	Housing H7 [mm]
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

Table 07: Important tolerances for plain bearings according to ISO 3547-1 after pressfit

Installation tolerances

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).