|General features||Unit||iglide® H1||test method|
|Max. moisture absorption at 73° F/50% R. H.||Wt.-%||0,1||DIN 53495|
|Max. moisture absorption||Wt.-%||0,3|
|Coefficient of surface friction, dynamic, against steel||µ||0,06 - 0,20|
|P x v value, max. (dry)||psi x fpm||22,800|
|Modulus of elasticity||psi||406,100||DIN 53457|
|Tensile strength at 68° F||psi||7,977||DIN 53452|
|Permissible static surface pressure (68° F)||psi||11,600|
|Shore D hardness||77||DIN 53505|
Physical and thermal properties
|Upper long-term application temperature||°F||392|
|Upper short-term application temperature||°F||464|
|Lower application temperature||°F||-40|
|Thermal conductivity||[W/m x K]||0,24||ASTM C 177|
|Coefficient of thermal expansion||[K-1 x 10-5]||6||DIN 53752|
|Specific volume resistance||Ωcm||> 1012||DIN IEC 93|
|Surface resistance||Ω||> 1011||DIN 53482|
For iglide® H1 plastic bushings running dry against a steel shaft, at 68°F.
iglide® H1 plastic bushings have been specially developed for use under extreme environmental conditions. Their strengths are the extremely high wear resistance and the excellent coefficients of friction even in applications in which the bushing is exposed to extreme temperatures and/or aggressive chemicals. iglidur® H1 plastic bushings can be used completely free of lubrication; in wet area applications, the surrounding medium acts as additional lubricant.
Figure 13.2 shows the elastic deformation of iglide® H1 with radial loads. Among the iglide® H materials, iglide® H1 material has the greatest elasticity. This is beneficial in applications with edge loads and is the reason for a higher mechanical loss factor that indicates the vibration dampening capacity of a material.
Due to the excellent coefficients of friction, rotating surface speeds up to 393 fpm are possible with iglide® H1 plastic bushings in dry operation. Linear speeds up to 984 fpm are attained. The speeds stated in Table 13.2 are limit values for the lowest bushing loads. With higher loads, the permitted speed drops with the extent of the load due to the limitations by the p x v value.
iglide® H is an extremely temperature-resistant material. With a short-term permitted maximum temperature of 464° F, the iglide® H plastic bushings can be subjected, for example, to a paint drying process at low loads.
iglide® H1 is a temperature-resistant material. The short-term permitted maximum temperature is 464°F, and this enables the iglide® H1 plastic bushings to be used, for instance, in a paint drying process without further load. With increasing temperatures, the compressive strength of iglide® H1 plastic bushings however declines. Figure 13.3 clarifies this connection. In addition to the ambient temperatures, the additional friction heat in the bushing system should be considered. The temperatures prevailing in the bushing system also have an influence on the bushing wear. The wear rises with increasing temperatures.
|iglide® H1||Application Temperature|
|Lower||- 40 °F|
|Upper, long-term||+ 392 °F|
|Upper, short-term||+ 464 °F|
|Additional axial securing||+ 176°F|
The coefficient of friction alters like the wear resistance with increasing load and speed. At constant load the coefficient of friction µ increases with the speed. At constant speed the coefficient of friction lowers with increasing load, whereupon almost constant values result from 5,802 psi. As the counter partner has a large influence on friction and wear, the choice of the appropriate shaft can be decisive. Smoother shafts than Ra = 0.1 µm raises the coefficient of friction. For applications with high loads, we recommend hardened and smoothed surfaces with an average surface finish of 12 - 16 rms.
|Coefficients of friction µ||0,06 - 0,2||0,09||0,04||0,04|
Figure 13.8 displays a summary of the results of tests with different shaft materials conducted with iglide® H1 plastic bushings in the igus® laboratory. Plastic bushings made of iglide® H1 display a distinctly different behavior with different shaft materials in rotating and pivoting applications. In rotating applications, the 440B and 304 stainless shafts are superior to the aluminum HC and 1050 steel shafts especially with high loads. In pivoting applications, the lowest wear rates were measured in combination with aluminum HC and 304 stainless shafts. With most shafts the rotation wear rates are somewhat lower than the pivoting wear rates.
Please contact us in case the shaft material scheduled by you is not included in this diagram.
|Shaft h9 |
|iglide® H1 |
|up to 3||0 - 0,025||+0,006 + 0,046|
|> 3 bis 6||0 - 0,030||+0,010 + 0,058|
|> 6 bis 10||0 - 0,036||+0,013 + 0,071|
|> 10 bis 18||0 - 0,043||+0,016 + 0,086|
|> 18 bis 30||0 - 0,052||+0,020 + 0,104|
|> 30 bis 50||0 - 0,062||+0,025 + 0,125|
|> 50 bis 80||0 - 0,074||+0,030 + 0,150|
iglide® H1 plastic bushings are press-in bushings for shafts with h-tolerance (recommended minimum h9).
The bushings 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 bushing automatically adjusts to the F10 tolerance.
|Greases, oils, without additives||+|
|Weak acids||+ to 0|
|Strong acids||+ to -|
|Strong alkaline||+ to -|
|Specific forward resistance||> 1012 Ωcm|
|Surface resistance||< 1011 Ω|
iglide® H1 plastic bushings have a good resistance against chemicals. Hence even chemicals can act as lubricants. The iglide® H1 plastic bushings are not resistant against hot, oxidizing acids and some other particularly aggressive chemicals.
The moisture absorption of iglide® H1 plastic bushings is about 0.1% in standard climatic conditions. The saturation limit in water is 0,3%. Therefore iglide® H1 is very well suited for use in wet environments.
iglide® H1 plastic bushings are only conditionally resistant to UV rays. The surface of iglide® H1 becomes coarser under the influence of atmospheric conditions; the wear increases.
Note: Water elements, even if only little, should be degassed for use in vacuum.
iglide® H1 plastic bushings are electrically insulating.