iglidur® GV0 - material data

Figure 02: Maximum recommended surface pressure dependent on the temperature (75 MPa to +20 °C)
 
X = Temperature [°C]
Y = Load [MPa]

Figure 03: Deformation under load and temperatures
 
X = Load [MPa]
Y = Deformatio [%]

Mechanical properties

The pressure resistance of iglidur® G V0 plain bearings declines with increasing temperatures. Fig. 02 clarifies this connection. With the long-term permitted application temperature of +130°C, the permitted surface pressure is less than 35 MPa. Maximum recommended surface pressure represents a mechanical material parameter. Tribological conclusions cannot be drawn from it.

Figure 03 shows the elastic deformation of iglidur® G V0 with radial loads. A plastic deformation can be negligent up to a pressure of about 100 MPa. It is however also dependent on the period of exposure.

m/s	Rotary	oscillating	Linear
Constant	1	0,7	4
Short-term	2	1,4	5

Table 02: Maximum surface speeds

Permitted surface speeds

iglidur® G V0 has been developed for low to medium surface speeds. The maximum values stated in the Table 02 can be attained only with minor pressure loads. In practice these limit values are not always reached due to interactions of different influences.

iglidur® G V0	Application temperature
Lower	- 40 °C
Upper, long-term	+ 130 °C
Upper, short-term	+ 210 °C
Secure axially in addition	+ 80 °C

Table 03: Temperature limits

Temperatures

The ambient temperatures influence the properties of bearings to a high degree. The short-term permitted maximum temperature is +210°C, which enables the use of the iglidur® G V0 bearings in applications where they can, for instance, be subjected to a paint drying process without further load. The temperatures prevailing in the bearing system also have an influence on the bearing wear. The wear increases with rising temperatures, with the influence especially marked from 120°C temperature onwards. Additional safety is required at temperatures over +100°C.

Figure 04: Coefficients of friction dependent on the surface speed, p = 1 MPa
 
X = Sliding 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

Just like the wear resistance, the coefficient of friction µ, friction coefficient in short, also alters with the load. Interestingly the coefficient of friction decreases with increasing load, whereas an increasing surface speed causes a rise in the coefficient of friction. This connection clarifies the extraordinary suitability of iglidur® G V0 bearings for high loads and low speeds (Fig. 04 und 05).

iglidur® G V0	Dry	Grease	Oil	Water
Coefficients of friction µ	0,15 - 0,23	0,09	0,04	0,04

Table 04: Coefficients of friction for iglidur® G V0 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 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

Friction and wear also depend to a high degree on the reverse partner. Very smooth shafts increase the coefficient of both friction and wear. A smoothed surface with an average surface finish of Ra = 0.6 to 0.8 µm is best suited for iglidur® G V0. Figure 06 shows an excerpt of the results of tests with different shaft materials, conducted with bearings made of iglidur® G V0. In this connection it is important to note that with increasing loads, the recommended hardness of the shaft increases. The "soft" shafts tend rather to wear themselves and thus increase the wear of the entire system. When the load exceeds 2 MPa, it should be noted that the wear rate (the slope of the curve) tends to decrease with the hardness of the shaft material. The comparison between rotating and pivoting motion shows that iglidur® G offers particular benefits when used for pivoting movements (Fig. 07). Please contact us in case the shaft material scheduled by you is not included here.

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

+ resistant      0 limited resistance      - not resistant
All specifications at room temperature[+20 °C]
Table 05: resistant to chemicals

Electrical properties

Specific forward resistance	< 1012 Ωcm
surface resistance	< 1011 Ω

Chemical resistance

iglidur® G V0 bearings have a good resistance against chemicals at room temperature. They are resistant to most lubricants. iglidur® G V0 is not affected by most weak organic and inorganic acids.
 

Radioactive rays

iglidur® G V0 bearings are radiation resistant up to a radioactive intensity of 3 · 10² Gy.
 

UV-resistant

iglidur® G V0 bearings are permanently resistant against UV rays.
 

Vacuum

In vacuum, iglidur® G V0 degases. The application in vacuum is possible only for dry bearings.
 

Electrical properties

iglidur® G V0 bearings are electrically insulating.

Maximum moisture absorption
by +23 °C/50 % r. F.	0,7 weight-%
Max. water absorption	4,0 weight-%

Table 06: Moisture absorption

Diagram 9: Effect of moisture absorption
 
X = Moisture absorption [weight %]
Y = Reduction of inside diameter [%]

Moisture absorption

The humidity absorption of iglidur® G V0 bearings amounts to about 0,7 Wt.-% in standard climatic conditions. The saturation limit in water is 4 %. This should be considered according to application conditions.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® G V0 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 iaw. ISO 3547-1 after press-fitting.

Installation tolerances

iglidur® G V0- 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 E10 tolerance.