iglide® M250

iglide M250 self-lubricating bearings are ideally suited for low to medium load applications. Impact resistance and vibration dampening, wear resistance and the ability to absorb dirt ingression represent the primary advantages of this bearing type.

iglide M250 is based on a thermoplastic alloy, modified for general load resistance and low wear. A mix of solid lubricants provides the self-lubricating effect during dry operation as well as a high crystalline level on the surface, thus increasing wear resistance substantially. (Illustration X)

iglide M250 is primarily used in the manufacture of agricultural, sports and leisure equipment, gardening tools, mountings for the construction industry, with furniture, boat manufacture, medical technology, machinery manufacture as well as packaging and textile machines.

Special Characteristics of iglide M250

  • Excellent vibration dampening characteristics, 250 times better than steel
  • Impact resistant
  • Excellent abrasion resistance
  • Ability to withstand dirt ingression
  • Maintenance-free dry operation due to solid lubricants
  • Quiet operation
  • Suited for slow rotating, oscillating and all linear motion
  • Possibility of retrofitting other bearing types
  • Cost effective
  • Dimensionally interchangeable with most powdered metal bearings


P x V Values
iglide M250 bearings are designed for low to average loads during continuous operation. Illustration X depicts the maximum permissible P x V values for dry operation. During dry operation, iglide M250 has a P x V value of up to 9,800 (psi x fpm).

While iglide M250 does not stand up well to high rotational speed during dry operation, this material features extremely high levels of wear resistance during slow rotating, oscillating and axial motion. Table 16 lists the surface speeds for various types of operation.

Compressive Strength
iglide M250 has a load capacity of approximately 1,740 psi at operating temperatures up to 240°F. Temperatures up to 390°F are possible for short duration. (Illustration X)

iglide M250 flanged bushings are capable of the same axial pressure through the bearing flange.
 

Maximum surface speed for iglide M250 during dry operation in fpm.
Rotating 
Oscillating 
Linear 
Continuous
295 
390 
975 
Short Duration
490 
590 
1180 

Coefficient of friction
During dry operation with hardened steel, the friction value of iglide M 250 varies between 0.18 and 0.30. Lower friction values can be achieved during lower speeds.

The friction value will decrease to 0.04 with permanent water or oil lubrication. (Table X)

Coefficients of friction for Iglide M250 against steel
Dry 
Grease 
Oil 
Water 
iglide M250
0.18 - 0.30 
0.09 
0.04 
0.04 
Steel shaft: Hardness 50 HRC, Ra=16-64 rms

The “start-up” capability during dry operation is excellent for iglide M250. Dynamic and static friction values are almost identical.

During the start-up phase, friction values will be higher than average until the microscopic abrasion has embedded into the shaft surface. Initial, one-time installation lubrication ensures quiet operation of the bearings from the start.

Operating Temperatures
iglide M250 will reach maximum performance during operating temperature up to 175°F. The recommended temperature for continuous operation is 240°F. During cold temperature operation, iglide M250 maintains its load capacity to -40°F (Table X).

Operating temperatures for iglide M250.
Wear 
Continuous 
 Short
Limit 
Operation 
Duration 
175°F 
240°F 
 390°F

Vibration Dampening Properties
The mecahnical loss factor for iglide M250 which is applied in measuring vibration dampening properties, is 250 times higher than for steel. As a result, the bearing operates quietly and vibratory noise is reduced to a minimum.

Electrical Properties
iglide M250 bearings are electrically isolating. The specific resistance is > 1013 Ohm/cm.

Radiation Resistance
Restriction apply if iglide M250 is to be used under the influence of rsadiation. Gamma rays in excess pof 10 MRad are capable of damaging the material, effecting a 50% reduction in performance.

Vacuum
iglide M250 can be used in vacuum environments.

Weather Resistance
iglide M250 is resistant to UV radiation. It is highly resistant to aging, and is the preferred choice for outdoor applications being corrosion and ozone resistant.

Chemical Resistance
iglide M250 is resistant to cleaning materials, benzine, oil, grease, alkaline solutions and several acid solutions of weak concentration. Please refer to the list of resistance values on page 16 for further details. Shaft Materials iglide M250 shows best results in conjunction with hardened steel shafts 50 RC, with a surface finish of Ra = 16-64 rms. Softer shaft materials may result in high levels of wear to the shaft. However, softer materials can be used in many applications with lower load requirements. Please refer to our technical sales engineers regarding your choice of shaft materials.

Fitting Practice
iglide M250 requires relatively high bearing tolerances for optimum performance. The excellent damping characteristics balances the effect of bearing tolerances. While such tolerances would not be acceptable for metallic bearings, they actually enhance some of the most significant advantages of iglide M250 bearings, namely wear resistance and zero maintenance requirements. Running clearances between shaft and bearing after assembly.

Shaft Materials
iglide M250 shows best results in conjunction with hardened steel shafts 50 RC, with a surface finish of Ra = 16-64 rms. Softer shaft materials may result in high levels of wear to the shaft. However, softer materials can be used in many applications with lower load requirements. Please refer to our technical sales engineers regarding your choice of shaft materials.

Running clearances between shaft and bearing after assembly.
iglide M250 Running Clearance
(in inches)
Nominal ID Max. Min.
0.1250 0.0039 0.0012
0.1875 0.0039 0.0012
0.2500 0.0048 0.0016
0.3125 0.0048 0.0016
0.3750 0.0048 0.0016
0.4375 0.0057 0.0020
0.5000 0.0057 0.0020
0.6250 0.0057 0.0020
0.6875 0.0057 0.0025
0.7500 0.0069 0.0025
0.8750 0.0069 0.0025
1.0000 0.0069 0.0025
1.1250 0.0069 0.0025
1.2500 0.0110 0.0032
1.3750 0.0110 0.0032
1.5000 0.0110 0.0032
1.6250 0.0110 0.0032
1.7500 0.0110 0.0032
2.0000 0.0110 0.0032
iglide M250 Running Clearance
(in mm)
Nominal ID Max. Min.
1 mm .105 .020
1.5 mm .105 .020
2 mm .105 .020
2.5 mm .105 .020
3 mm .105 .020
4 mm .135 .030
5 mm .135 .030
6 mm .135 .030
7 mm .166 .040
8 mm .166 .040
9 mm .166 .040
10 mm .166 .040
12 mm .203 .050
14 mm .203 .050
15 mm .203 .050
16 mm .203 .050
18 mm .203 .050
20 mm .247 .065
22 mm .247 .065
24 mm .247 .065
25 mm .247 .065
26 mm .247 .065
27 mm .247 .065
28 mm .247 .065
30 mm .247 .065
32 mm .302 .080