iglidur® B - 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

Maximum recommended surface pressure represents a mechanical material parameter. Tribological conclusions cannot be drawn from it. The pressure resistance of iglidur® B bearings declines with increasing temperatures. Fig. 02 clarifies this connection.

The deformation at 40 MPa at room temperature is 5.3% (Fig. 03).

Maximum surface speed

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

Table 02: Maximum surface speeds

Permitted surface speeds

iglidur® B bearings can be continuously used in rotations for up to 0.7 m/s. The frictional heat provides the speed limits.

Because of the interactions, the specified maximum values are often not accomplished in practice.

iglidur® B	Operating temperature
Lower	- 40 °C
Upper, long-term	+ 100 °C
Upper, short-term	+ 130 °C
Secure axially in addition	+ 50 °C

Table 03: Temperature limits for iglidur® B

Temperatures

The operating temperature of the iglidur® B bearings is limited to 100° C. From 50° C onward, the very soft bearing should be mechanically fastened, so that the danger of bushings creeping out of the bores is avoided. The wear resistance too declines disproportionately from 70° C.

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 coefficients of friction increase slightly with the speed and decrease with the load. Shaft surface finishes between 0.4 and 0.6 Ra are ideal. Providing the bearing load is not too high, the attained coefficients of wear are very good. An increase in load results in a disproportionate increase in abrasion.
 

iglidur® B	Dry	Grease	Oil	Water
Coefficients of friction µ	0,18 - 0,28	0,09	0,04	0,04

Table 04: Coefficients of friction for iglidur® B 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

The influence of the shaft material is not very large in wear resistance.
 
Figures 06 and 07 clarify that very similar wear data are attained with different shaft materials. If high operational performances are expected, the bearing load should not be too high.

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

+ resistant      0 partially resistant      - non-resistant
All specifications at room temperature [+20°C] Table 05: Chemical resistance of iglidur® B

Electrical properties

Specific forward resistance	> 1010 Ωcm
Surface resistance	> 109 Ω

Chemical resistance

iglidur® B bearings are not very resistant to chemicals For chemical resistance, there are other iglidur® materials available with better properties.

Radioactive rays

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

UV-resistant

iglidur® B bearings are not resistant to the influence of UV rays.

Vacuum

The use in vacuum is possible only conditionally. Only dry bearings made of iglidur® B should be tested in vacuum.

Electrical properties

Bearings made of iglidur® B are electrically insulating.

Maximum moisture absorption
by +23 °C/50 % r. F.	1,0 weight-%
Max. water absorption	6,3 weight-%

Table 06: Moisture absorption of iglidur® B

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

humidity absorption / moisture absorption

The moisture absorption is relatively high and must be considered in the selection and design.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® B 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® B bearings according to ISO 3547-1 after the press-fit.

Installation tolerances

iglidur® B bearings are standard bearings for shafts with h-tolerance (recommended minimum 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. In certain dimensions the tolerance in dependence on the wall thickness deviates from this (See delivery program )