iglidur® H - Material data

Figure 02: Maximum recommended surface pressure dependent on the temperature (90 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. With increasing temperatures, the compressive strength of iglidur® H plain bearings decreases. Fig. 02 clarifies this connection.
 
Figure 03 shows the elastic deformation of iglidur® H with radial loads. Under the maximum recommended surface pressure of 90 MPa, the deformation amounts to about 2.5%.

Maximum surface speed

m/s	Rotary	oscillating	Linear
Constant	1	0,7	3
Short-term	1,5	1,1	4

Table 02: Maximum surface speeds

Permitted surface speeds

The maximum permitted surface speed is dependent on whether the temperature in the bearing location rises strongly or not. iglidur® H is suited in dry operation for a maximum surface speed of 1 m/s (rotating) and 4 m/s (linear) respectively. Linear movements enable higher surface speeds, as a large area of the shaft contributes to the cooling.

iglidur® H	Operating temperature
Lower	- 40 °C
Upper, long-term	+ 200 °C
Upper, short-term	+ 240 °C
Secure axially in addition	+ 120 °C

Table 03: Temperature limits for iglidur® H

Temperatures

With increasing temperatures, the compressive strength of iglidur® H plain bearings decreases. Fig. 02 clarifies this connection.
 
The temperatures prevailing in the bearing system also have an influence on the bearing wear. An additional securing is recommended at temperatures higher than +120°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 coefficient of friction alters like the wear resistance with increasing load.
Interestingly, the friction coefficient µ lowers slightly with the increase of surface speed at constant load (see Figures. 04 and 05)

iglidur® H	Dry	Grease	Oil	Water
Coefficients of friction µ	0,07 - 0,2	0,09	0,04	0,04

Table 04: Coefficients of friction for iglidur® G 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 Fig. 06 and 07 display the results of tests with different shaft materials conducted with plain bearings made of iglidur® H.
 
Bearings made of iglidur® H display a distinctly different behaviour with different shaft materials in rotating and swivelling applications. While the Cf53 and St37 shafts feature the best coefficients of wear in rotating applications, the V2A shaft that figures way below in rotating movements is, besides the St37, the most suited for pivoting movements. In contrast, hard-chromed shafts with iglidur® H bearings have advantage only with very low loads.

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

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

Electrical properties

Specific forward resistance	< 105 Ωcm
Surface resistance	< 102 Ω

iglidur® H bearings are electrically insulating.

Chemical resistance

iglidur® H bearings have a good resistance against chemicals. Hence even an aggressive chemical can act as lubricant.

The iglidur® H bearings cannot withstand hot, oxidizing acids.

Radioactive rays

iglidur® H withstands both the neutron and gamma particle radiations without noticeable loss to its excellent mechanical properties. iglidur® H bearings are radiation resistant up to a radioactive intensity of 2 x 10² Gy.

UV-resistant

iglidur® H bearings are only conditionally resistant to UV rays. Under the influence of weathering, the surface of iglidur® H becomes harsher, and the compressive strength of the material drops.

Vacuum

Note that for use in vacuum, water elements, even if only little, should be degassed.

Electrical properties

iglidur® H bearings are electrically conductive.

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

Table 06: Humidity absorption of iglidur® H

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

humidity absorption / moisture absorption

The humidity absorption of iglidur® H bearings is about 0.1% in standard climatic conditions. The saturation limit in water is 0,3 %. iglidur® H does not soak and is therefore very well suited for application in wet environment.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® H F10 [mm]	Housing H7 [mm]
Up to 3	0 - 0,025	+0,006 +0,046	0 +0,010
> 3 to 6	0 - 0,030	+0,010 +0,058	0 +0,012
> 6 to 10	0 - 0,036	+0,013 +0,071	0 +0,015
> 10 to 18	0 - 0,043	+0,016 +0,086	0 +0,018
> 18 to 30	0 - 0,052	+0,020 +0,104	0 +0,021
> 30 to 50	0 - 0,062	+0,025 +0,125	0 +0,025
> 50 to 80	0 - 0,074	+0,030 +0,150	0 +0,030

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

Installation tolerances

iglidur® H 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 F10 tolerance. In certain dimensions the tolerance in dependence on the wall thickness deviates from this (See delivery program )