iglide® A290 - Material data

Maximum surface speed

m/s	Rotating	Oscillating	Linear
Constant	1	0,7	4
Short-term	2	1,4	4

Permitted surface speeds

iglide® A290 is suitable for low surface speeds. Due to the relatively high friction particularly in the low load range, the bearings made of iglide® A290 heat more strongly than other bearings. With higher speeds, the friction also increases.

Figure 9.3: Maximum recommended surface pressure dependent on the temperature

Temperatures

The short-term permitted maximum temperature is 180° C.

With increasing temperatures, the compressive strength of iglide® A290 bearings decreases. The diagram 9.3 clarifies this connection.

The temperatures prevailing in the bearing system also have an influence on the bearing wear. The wear increases with rising temperatures, and the influence is especially marked from 120° C temperature onwards.

Temperature limits

iglide® A290	Application temperature
Lower	- 40 °C
Upper, long-term	+ 140 °C
Upper, short-term	+ 180 °C

Figure 2.4: Coefficients of friction dependent on the surface speed, p = 0.75 MPa

Friction and wear

The coefficient of friction alters like the wear resistance with increasing load and surface speed.. With increasing speed and constant load, the coefficient of friction steadily rises. In contrast a reverse behavior is noticed at increasing load and constant speed (see Figures. 9.4 and 9.5) Friction and wear depend to a high degree on the reverse partner. Very smooth shafts increase the coefficient of both friction and wear. iglide® A290 proves to be relatively insensitive to shaft surfaces and retains a 0.4 friction coefficient µ with average surface finishes of Ra = 0.4 to 1.6 µm.

Coefficients of friction for iglide® A290 against steel
(Ra = 1 µm, 50 HRC)

iglide® A290	Dry	Fat	Oil	Water
Coefficients of friction µ	0,13 - 0,40	0,09	0,04	0,04

Fig. 2.7: Wear, rotating application with different shaft materials, load p = 0.75 MPa, v = 0.5 m/s

Shaft materials

Figure 9.7 displays a summary of the results of tests with different shaft materials conducted with bearings made of iglide® A290.

Compared to iglide® A200, the improved tribological properties of iglide® A290 are also reflected in the coefficients of wear. At low loads, the differences in the wear resistance of the combinations of iglide® A290 with different shaft materials are very distinct. Figure 9.8 shows that the advantage of hard-chromed shafts increases with rising load. This counter partner is also well-suited for pivoting applications and are frequently found in packaging machines. Other hardened surfaces such as the Cf53 are also recommended.

Important tolerances for iglide® A290 bearings according to ISO 3547-1 after the press-fit.

Diameter d1 [mm]	Shaft h9 [mm]	iglide® A290 D11 [mm]
Up to 0.5	0 - 0,025	+0,020 + 0,080
> 3 to 6	0 - 0,030	+0,030 + 0,105
> 6 to 10	0 - 0,036	+0,040 + 0,130
> 10 to 18	0 - 0,043	+0,050 + 0,160
> 18 to 30	0 - 0,052	+0,065 + 0,195
> 30 to 50	0 - 0,062	+0,080 + 0,240

Installation tolerances

iglide® A290 bearings are standard bearings for shafts with h-tolerance (recommended minimum h9).

After the installation in a housing bore with the tolerance H7, the inner diameter of the bearing automatically adjusts to the D11 tolerance.

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

+ resistant      0 conditionally resistant      - non-resistant

Figure 9.10: Influence of humidity absorption of iglide® A290 bearings

Electrical properties

Specific forward resistance	> 1011 Ωcm
Surface resistance	> 1011 Ω

Chemical resistance

iglide® A290 bearings have a good resistance against chemicals. They are resistant to most lubricants. The iglide® A290 is not affected by most weak organic and inorganic acids.

The humidity absorption of iglide® A290 bearings amounts to about 1,7% in standard climatic conditions. The saturation point in water is at 7.3%, a disadvantage which must be accounted for by all means in applications in humid and wet areas.

Please contact us if there is any query about clearance design in humid applications.

Radioactive rays

iglide® A290 bearings are radiation resistant up to a radioactive intensity of 3 x 10² Gy.

UV-resistant

iglide® A290 bearings are resistant to UV radiation, but the tribological properties deteriorate.

Vacuum

The iglide® A290 bearings can be used in vacuum only restrictedly due to the high humidity absorption.

Electrical properties

iglide® A290 bearings are electrically insulating.