iglidur® C - Material data

Figure 02: Maximum recommended surface pressure dependent on the temperature (40 MPa to +20 °C)

X = Temperature [°C]
Y = Load [MPa]

Figure 03: Deformation under load and temperatures

X = Load [MPa]
Y = Deformation [m/s]

Mechanical properties

The pressure resistance of iglidur® C bearings declines with increasing temperatures. Fig. 02 highlights this correlation. The maximum recommended surface pressure is a mechanical material parameter. Tribological conclusions cannot be drawn from it.

Figure 03 shows the elastic deformation of iglidur® C with radial loads. The high flexibility makes the bearing suitable for vibrations and edge loads.

m/s	Rotary	oscillating	Linear
Constant	1	0,7	2
Short-term	1,5	1,1	3

Table 02: Maximum surface speeds

Permitted surface speeds

Though important solid lubricants have been deliberately dispensed with in the development of the iglidur® C, the bearings are very wear resistant and for this reason suitable also for continuous movements at medium surface speeds. Though speeds up to 1.5 m/s are attained on the short term, the main applications should however be undertaken with speeds below 0.5 m/s.

iglidur® C	Operating temperature
Lower	- 40 °C
Upper, long-term	+ 90 °C
Upper, short-term	+ 130 °C
Secure axially in addition	+ 40 °C

Table 03: Temperature limits for iglidur® C

Temperatures

The upper short-term application temperature is +130°C. However no more loads are possible at this temperature. Therefore it would be reasonable to limit the temperature to about 80 up to 90° C. Note that the bearing should be mechanically fastened to the housing from temperatures of +40° C to counteract the danger of loosening of the bearing.

Figure 04: Coefficients of friction dependent on the surface speed, p = 0,75 MPa

X = Surface speed [m/s]
Y = Coefficient of friction μ

Figure 05: Coefficients of friction dependent on the load, v = 0,01 m/s

X = Load [MPa]
Y = Coefficient of friction μ

Friction and wear

The coefficient of friction of the iglidur® C bearing is dependent to a large degree on the coarseness of the shaft. Similarly the wear of the bearing is very good in applications with rotating or pivoting motions with low loads.
 

iglidur® C	Dry	Grease	Oil	Water
Coefficients of friction µ	0,17 - 0,25	0,09	0,04	0,04

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

Figure 06: Wear, rotating application with different shaft materials, p = 1 MPa, v = 0.3 m/s
 
X = shaft materials
Y = wear [μm/km]
 
A = Aluminum, hard-anodized
B = machining steel
C = Cf53
D = Cf53, hard chrome-plated
E = St37
F = V2A
G = X90

Shaft materials

Figure 06 clearly shows how important the "suitable" counter partner can be. Although all the results shown from these rotation experiments can be regarded as very good, the difference is sometimes significant. This difference becomes even greater as the load increases.

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

+ resistant      0 limited resistance      - not resistant
All specifications at room temperature[+20 °C]
Table 05: Chemical resistance of the iglidur® bearings C

Electrical properties

Specific forward resistance	> 1010 Ωcm
Surface resistance	> 109 Ω

Chemical resistance

iglidur® C bearings are resistant to cleaning agents, fats, oils, diluted alkalis and weak acids.

Radioactive rays

iglidur® C bearings are resistant up to a radioactive intensity of 2 x 10⁴ Gy. Higher radiations affect the material and can lead to the loss of important mechanical properties.

UV-resistant

iglidur® C bearings are not resistant against UV rays. In outdoor applications or in other applications with intensive radiation, adequate protection against direct radiation should be provided.

Vacuum

The iglidur® C bearings can be used in vacuum only restrictedly. Potentially existent humidity degasses.

Electrical properties

iglidur® C bearings are electrically insulating.

Maximum moisture absorption
by +23 °C/50 % r. F.	1,0 weight-%
Max. water absorption	7,0 weight-%

Table 06: Moisture absorption of iglidur® C

Diagram 10: Effect of moisture absorption
 
X = Moisture absorption [weight %]
Y = Reduction of inside diameter [%]

humidity absorption / moisture absorption

The humidity absorption of iglidur® C bearings amounts to about 7% with saturation in water and therefore this should be accounted for in applications in a humid environment.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® C D11 [mm]	Housing H7 [mm]
Up to 3	0 - 0,025	+0,020 +0,080	0 +0,010
> 3 to 6	0 - 0,030	+0,030 +0,105	0 +0,012
> 6 to 10	0 - 0,036	+0,040 +0,130	0 +0,015
> 10 to 18	0 - 0,043	+0,050 +0,160	0 +0,018
> 18 to 30	0 - 0,052	+0,065 +0,195	0 +0,021
> 30 to 50	0 - 0,062	+0,080 +0,240	0 +0,025
> 50 to 80	0 - 0,074	+0,100 +0,290	0 +0,030

Table 07: Important tolerances for iglidur® C bearings according to ISO 3547-1 after the press-fit.

Installation tolerances

iglidur® C plain bearings are standard bearings for shafts with tolerance h (minimum recommendation is h9).
 
The bearings are designed for press-fit in a housing with h7 tolerance. After the installation in a housing with nominal diameter, the inner diameter of the bearing automatically adjusts to the D11 tolerance.