iglidur® T220 - 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® T220 bearings declines with increasing temperatures. Fig. 02 clarifies this connection.
 
iglidur® T220 bearings can be stressed up to the permitted limit of 45 MPa. The deformation is then virtually at 2%. The permitted load is limited by higher temperatures. (Fig. 02).

Maximum surface speed

m/s	Rotary	oscillating	Linear
Constant	0,4	0,3	1
Short-term	1	0,7	2

Table 02: Maximum surface speeds

Permitted surface speeds

The maximum surface speeds of iglidur® T220 bearings amount to 0.4 m/s with continuous rotation. The friction and the entailing heating limit the permitted speeds. From this it follows that higher speeds can be attained in intermittent service or in linear movements.

iglidur® T220	Operating temperature
Lower	- 40 °C
Upper, long-term	+ 100 °C
Upper, short-term	+ 160 °C
Secure axially in addition	+ 50 °C

Table 03: Temperature limits for iglidur® T220

Temperatures

The elasticity of the bearing is dependent on the temperature. Even 60°C leads to a significant increase in elasticity. A mechanical fastening should be considered from +50°C upward.

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

By complying with the requirements established by the tobacco processing industry, the coefficients of friction and wear of the iglidur® T220 bearings are clearly behind those of the best iglidur® bearings. The coefficient of friction decreases with the load while it increases only slightly at higher speeds.

iglidur® T220	Dry	Grease	Oil	Water
Coefficients of friction µ	0,2 - 0,32	0,09	0,04	0,04

Table 04: Coefficients of friction for iglidur® T220 against steel (Ra = 1 µm, 50 HRC)

Fig. 06: Wear, rotating application with various shaft materials p = 1 MPa, v = 0.3m/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

Fig. 06 shows the test results with different shaft materials conducted with bearings made of iglidur® T220.
Figure 07 shows that with increase in load, the bearing responds with stronger increase in wear. Therefore care should be taken to maintain the loads under 5 MPa through adequate dimensioning of the bearing.

Medium	Resistance
Alcohols	+
Hydrocarbons	-
Fats, oils, without additives	+
Fuels	+
Diluted acids	0
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® T220

Electrical properties

Specific forward resistance	> 1010 Ωcm
Surface resistance	> 1010 Ω

Chemical resistance

iglidur® T220 bearings are resistant to highly diluted alkalis and very weak acids.

Radioactive rays

iglidur® T220 bearings are radiation resistant up to a radioactive intensity of 3 x 10² Gy.

UV-resistant

iglidur® T220 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® T220 should be tested in vacuum.

Electrical properties

Bearings made of iglidur® T220 are electrically insulating.

Delivery program

The iglidur® T220 bearings are manufactured according to order specifications.

Maximum moisture absorption
by +23 °C/50 % r. F.	0,3 weight-%
Max. water absorption	0,5 weight-%

Table 06: Moisture absorption of iglidur® T220

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

Moisture absorption

The humidity absorption of iglidur® 200 bearings amounts to about 0,3% in standard climatic conditions. The saturation limit in water is 0,5 %. These values are so low that a moisture expansion need to be considered only in extreme cases.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® T220 E10 [mm]	Housing H7 [mm]
Up to 3	0 - 0,025	+0,014 +0,054	0 +0,010
> 3 to 6	0 - 0,030	+0,020 +0,068	0 +0,012
> 6 to 10	0 - 0,036	+0,025 +0,083	0 +0,015
> 10 to 18	0 - 0,043	+0,032 +0,102	0 +0,018
> 18 to 30	0 - 0,052	+0,040 +0,124	0 +0,021
> 30 to 50	0 - 0,062	+0,050 +0,150	0 +0,025
> 50 to 80	0 - 0,074	+0,060 +0,180	0 +0,030
> 80 to 120	0 - 0,087	+0,072 +0,212	0 +0,035
> 120 to 180	0 - 0,100	+0,085 +0,245	0 +0,040

Table 07: Important tolerances for iglidur® T220 bearings according to ISO 3547-1 after the press-in.

Installation tolerances

iglidur® T220- 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 bore with H7 tolerance, the inner diameter of the bearing automatically adjusts to the E10 tolerance.