iglidur® Q - Material data

Figure 02: Maximum recommended surface pressure dependent on the temperature (100 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® Q bearings declines with increasing temperatures. Fig. 02 clarifies this connection.

iglidur® Q is a material used when high p x v values are reached through high loads. Fig. 03 shows the elastic deformation of iglidur® Q during radial loading. Under the maximum recommended surface pressure of 100 MPa, the deformation at room temperature amounts to less than 3 %.

Maximum surface speed

m/s	Rotary	oscillating	Linear
Constant	1	0,7	5
Short-term	2	1,4	6

Table 02: Maximum surface speeds

Permitted surface speeds

Under extreme radial loads, the iglidur® Q bearings can reach the maximum p x v values possible in dry operation with iglidur® bearings. Although the iglidur® Q bearings offer the greatest advantages when subject to high loads and low speeds, high surface speeds are also attainable due to these bearings’ excellent coefficients of friction. The values in Table 02 show the speeds at which the temperature rises to the maximum permitted value as a result of friction.

Temperature limits

iglidur® Q	Operating temperature
Lower	- 40 °C
Upper, long-term	+ 135 °C
Upper, short-term	+ 155 °C
Secure axially in addition	+ 50 °C

Table 03: Temperature limits for iglidur® Q

Temperatures

The iglidur® Q bearings retain their excellent wear resistance in high temperatures as well. Additional safety is required at temperatures over +50°C. Also note that the coefficient of friction strongly increases dependent on the temperature from about +100°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

Friction and wear

Many dry-running plastic bearings feature decreasing coefficients of friction with increasing loads. In this regard, iglidur® Q again surpasses most iglidur® bearings: the material offers outstanding coefficients of friction under high loads (Fig. 04 and 05).

iglidur® Q	Dry	Grease	Oil	Water
Coefficients of friction µ	0,05 - 0,15	0,09	0,04	0,04

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

Figure 06: Wear, rotating application with different shaft materials, p = 30 MPa, v = 0,01 m/s
 
X = shaft materials
Y = wear [μm/km]
 
A = C45
B = St52
C = St52 gas nitrified
D = St52 salt bath nitrocarburized
E = St52 galvanised
F = 16MnCr5 yellow galvanised
G = 20MnV6, unhardened, hard chrome-plated
H = 38MnV S6, hardened, hard chrome-plated

Shaft materials

Diagram 06 shows results of testing different shaft materials with plain bearings made from iglidur Q. The strengths of iglidur heavy-duty materials become clear from 30MPa. iglidur Q stands out in particular. Other heavy-duty materials such as iglidur Q2 and igutex TX1 only offer the best performances in terms of wear when subjected to even higher loads. iglidur Q shows strikingly good wear properties on many different shaft materials.

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: Chemical resistance of the iglidur® bearings Q

Electrical properties

Specific forward resistance	> 1015 Ωcm
Surface resistance	> 1012 Ω

Chemical resistance

iglidur® Q bearings have a good resistance against chemicals. They possess an excellent resistance to organic solvents, fuels, oils and fats. The material is only partially resistant to weak acids and alkalis.

Radioactive rays

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

UV-resistant

The tribological properties of the iglidur® Q bearings remain largely constant under climatic influences. However a minor embrittlement occurs in the material.

Vacuum

In application in vacuum, the potentially existent moisture content is degassed. For this reason only the dry iglidur® Q bearings are suitable for vacuum.

Electrical properties

Bearings made of iglidur® Q are electrically insulating.

Maximum moisture absorption
by +23 °C/50 % r. F.	0,9 weight-%
Max. water absorption	4,9 weight-%

Table 06: Moisture absorption of iglidur® Q

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

humidity absorption / moisture absorption

The humidity absorption of iglidur® 200 bearings amounts to about 0,9% in standard climatic conditions. The saturation limit in water is 4,9 %. This should be considered according to application conditions.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® Q 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® Q bearings according to ISO 3547-1 after the press-fit.

Installation tolerances

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