iglidur® UW500 - Material data

Figure 02: Maximum recommended surface pressure dependent on the temperature (140 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® UW500 plain bearings decreases. Fig. 02 clarifies this connection.
 
Figure 03 shows the elastic deformation of iglidur® UW500 with radial loads.

Maximum surface speed

m/s	Rotating	Oscillating	Linear
Constant	0,8	0,6	2
Short-term	1,5	1,1	3

Permitted surface speeds

iglidur® UW500 plain bearings can be used in both dry operation and in liquids in a wide range of applications. Through a hydrodynamic lubrication, as it can be attained under water with high speeds, surface speeds far above 1.5 m/s can be achieved.

Figure 29.3: Maximum recommended surface pressure dependent on the temperature

iglidur® UW500	Application temperature
Lower	- 100 °C
Upper, long-term	+ 250 °C
Upper, short-term	+ 300 °C
Secure axially in addition	+ 150 °C

Table 03: Temperature limits for iglidur® UW500

Temperatures

iglidur® UW500 can be used in applications with continuous temperatures of +150°C. With special fastening of the bearing, these temperatures can go even beyond +200°C. The iglidur® UW500 is one of the most temperature-resistant iglidur® materials. An additional securing is recommended at temperatures higher than +150°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 2.4: Coefficients of friction dependent on the surface speed, p = 0.75 MPa

Friction and wear

Fig. 04 and 05 show the coefficients of friction of iglidur® UW500 plain bearings depending on surface speed and load. Friction and wear also depend to a high degree on the reverse partner. Ideal are smoothed surfaces with an average surface finish of Ra of 0.1 to 0.4.

Coefficients of friction for iglidur® UW500 against steel
(Ra = 1 µm, 50 HRC)

iglidur® UW500	Dry	Grease	Oil	Water
Coefficients of friction µ	0,2 - 0,36	0,09	0,04	0,04

Figure 06: Wear, rotating application with different shaft materials, p = 1 MPa, v = 0,3 m/s
 
X = Shaft material
Y = Wear [μm/km]
 
A = Aluminum, hard-anodized
B = machining steel
C = Cf53
D = Cf53, hard-chromed
E = St37
F = V2A
G = X90

Shaft materials

The Fig. 06 displays a summary of the results of tests with different shaft materials conducted with plain bearings made of iglidur® UW500.

Medium	Resistance
Alcohols	+
Hydrocarbons	+
Greases, oils without additives	+
Fuels	+
Diluted acids	+
Strong acids	+
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 UW500

Electrical properties

Specific forward resistance	> 109 Ωcm
Surface resistance	> 109 Ω

Chemical resistance

iglidur® UW500 bearings have almost universal chemical resistance. They are affected only by concentrated nitric acid and sulfuric acid. The chemicals list given at the end of this catalog gives detailed information over this.

The humidity absorption of iglidur® UW500 bearings is extremely low. In standard climatic conditions, it lies below 0.1 Wt-%. Thus the iglidur® UW500 bearings can be even mounted for underwater applications without any adaptation to the installation conditions. The maximum water absorption is 0.5 Wt-%.

Radioactive rays

iglidur® UW500 bearings are radiation resistant up to a radioactive intensity of 1 x 10⁵ Gy. iglidur® UW500 thus figures among the most radiation-resistant materials in the iglidur® product range. iglidur® UW500 is extremely resistant to strong gamma rays and withstands a radiation dose of 1,000 Mrad without any perceptible loss of any of its properties. The material also overcomes an alpha or beta radiation of 10,000 Mrad virtually unscathed.

UV-resistant

The excellent material features of the iglidur® UW500 do not alter under UV radiation and other climatic influences.

Vacuum

The iglidur® UW500 bearings can also be used almost unrestrictedly in vacuum. An evaporation takes place only to a minor degree.

Delivery program

The iglidur® UW500 bearings are manufactured according to order specifications.

Maximum moisture absorption
by +23 °C/50 % r. F.	0,1 weight-%
Max. water absorption	0,5 weight-%

Table 06: Moisture absorption

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

humidity absorption / moisture absorption

The humidity absorption of iglidur® UW500 bearings is extremely low. In standard climatic conditions, it lies below 0.1 Wt-%. Thus the iglidur® UW500 bearings can be even mounted for underwater applications without any adaptation to the installation conditions. The maximum water absorption is 0.5 Wt-%.

Important tolerances for iglidur® UW500 bearings according to ISO 3547-1 after the press-fit.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® UW500 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 iaw. ISO 3547-1 after press-fitting.

Installation tolerances

iglidur® UW500 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 )