iglidur® A350 - Material data

Materials table

General features Unit iglidur® A350 test method
Density g/cm³ 1,42
Colour blue
Max. humidity absorption at 23°C/50% R. H. % weight 0,6 DIN 53495
Max. water absorption % weight 1,9
Coefficient of surface friction, dynamic, against steel µ 0,10 - 0,20
PV values max. (dry) MPa x m/s 0,4

Mechanical properties
Bending E-module MPa 2.000 DIN 53457
Tensile strength at +20 °C MPa 110 DIN 53452
compressive strength MPa 78
Maximum recommended surface pressure (20° C) MPa 60
Shore D hardness 76 DIN 53505

Physical and thermal properties
Max. long term application temperature °C +180
Max. short term application temperature °C +210
Lower application temperature °C -100
Heat conductivity [W/m x K] 0,24 ASTM C 177
Coefficient of thermal expansion (at 23° C) [K-1 x 10-5] 8 DIN 53752

Electrical properties
Specific forward resistance Ωcm > 1011 DIN IEC 93
Surface resistance Ω > 1011 DIN 53482

Figure 01: Permitted pv-values for iglidur® A350 bearings


Figure 01: Permitted PV values for iglidur® A350 bearings with 1 mm wall thickness in dry operation against a steel shaft, at 20°C, installed in a steel housing.

X = Surface speed [m/s]
Y = Load [MPa]
iglidur® A350 bearings are made in such a way that they can be used in any loads applicable in the food and packaging industries. Even high loads, as in lifting devices or presses, are no problem and the bearings work reliably without additional lubrication.

Figure 02: Maximum recommended surface pressure dependent on the temperature (60 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® A350 bearings decreases. Fig. 02 clarifies this connection.
 
Figure 03 shows how iglidur® A350 elastically deforms under radial load. Under the maximum surface pressure of 60 MPa, the deformation amounts to less than 5%.

Maximum surface speed

m/s Rotary oscillating Linear
Constant 1 0,8 2,5
Short-term 1,2 0,9 3
Table 02: Maximum surface speeds

Permitted surface speeds

iglidur® A350 bearings are well suited for low and medium speeds, both in rotating and oscillating applications. The wear rates are similar, which means there is no preferred type of motion. Linear motions can also be well mounted with iglidur® A350. In case of high speeds it should be tested whether iglidur® J or iglidur® L250 can be used, as the wear rate of these bearings is lower.

iglidur® A350 Application temperature
Lower - 100 °C
Upper, long-term + 180 °C
Upper, short-term + 210 °C
Secure axially in addition + 140 °C
Table 03: Temperature limits

Temperatures

The temperature resistance makes iglidur® A350 the ideal material for bearings in the food industry. An additional securing is recommended at temperatures higher than +140°C. The wear rate of the iglidur® A350 plain bearings increases only minimally with higher temperatures. Tests have shown good wear results in all tested shaft materials at temperatures of +100°C.

Figure 04: Coefficients of friction dependent on the surface speed, p = 1 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 of iglidur® A350 against steel lie in an average range (Fig. 04 and 05).
iglidur® A300 Dry Grease Oil Water
Coefficients of friction µ 0,1 - 0,2 0,09 0,04 0,04

Table 04: Coefficients of friction for iglidur® A350 against steel (Ra = 1 μm, 50 HRC)

Fig. 06: Wear, rotating application with various shaft materials Figure 06: Wear, rotating application with different shaft materials, p = 1 MPa, v = 0,5 m/s
 


X = Shaft material
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 corrosion-resistant steels are rather considered natural for use in the food industry. The trials were therefore carried out especially on such materials. It has been shown that there is no clear favorite and both A2 and X90 and hard chrome-plated steel are suitable. Hard anodized aluminum is also well suited for both linear and rotating movements.
Fig. 07: Wear with various shaft materials Figure 07: Wear with various shaft materials in the rotating operation dependent on the load

X = Load [MPa]
Y = Wear [μm/km]

A = Cf53
B = V2A
C =X90

Medium Resistance
Alcohols +
Hydrocarbons + to 0
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 iglidur® A350


Electrical properties

Specific forward resistance > 1011 Ωcm
Surface resistance > 1011 Ω

chemical resistance

iglidur® A350 plain bearings are resistant to diluted acids and alkalis, alcohols and detergents. They are also resistant to most lubricants. The iglidur® A350 bearings are resistant to common cleaning agents used in the food industry. iglidur® A350 is affected by esters, ketones, chlorinated hydrocarbons, aromatics and highly polar solvents.

Radioactive rays

iglidur® A350 bearings are radiation resistant up to a radiation intensity of 2 x 102 Gy.

UV-resistant

iglidur® A350 bearings are well resistant against UV rays.
 

Vacuum

In vacuum, iglidur® A350 degases. The application in vacuum is possible only for dry bearings.

Electrical properties

iglidur® A350 bearings are electrically insulating.

Maximum moisture absorption
by +23 °C/50 % r. F. 0,6 weight-%
Max. water absorption 1,9 weight-%
Table 06: Humidity absorption of iglidur® A350
Effect of moisture absorption on plain bearings Diagram 10: Effect of moisture absorption
 
X = Moisture absorption [weight %]
Y = Reduction of inside diameter [%]

humidity absorption

The moisture absorption of iglidur® A350 is low and can be disregarded when using standard bearings. Even at full saturation the iglidur® A350 does not absorb more than 1.9% of water.

Diameter
d1 [mm]
Shaft
h9 [mm]
iglidur® A350
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® A350 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.