Bearing data

Radial spherical plain bearings requiring maintenance
Dimension standardsMetric bearings:
ISO 12240-1:1998
  • GE series → dimension series E
    (GEM series: non-standard (extended) inner ring width, otherwise same dimensions as GE series)
  • GEH series → dimension series G
  • GEG series → dimension series W

Inch bearings in the GEZ series:
ANSI/ABMA Std. 22.2-1988 (except for the inner ring width in the GEZM series)

Tolerances
Metric bearings in the GE, GEG, GEH and GEM series:
ISO 12240-1:1998 (table 1)

Inch bearings in the GEZ, GEZH and GEZM series:
ANSI/ABMA Std. 22.2-1988 (table 2)
Outer ring tolerances apply to conditions before fracture and surface treatment.
Accordingly, inner ring tolerances apply to rings before surface treatment.

Radial internal clearance

Normal as standard
Check availability of C2 (smaller) or C3 (larger) prior to ordering.


Values:

metric bearings:
ISO 12240-1:1998 (table 3)

inch bearings (table 4)


Materials

Inner and outer rings: through-hardened, ground and phosphated bearing steel; sliding contact surfaces are treated with a running-in lubricant

Seals (table 5)


Permissible operating temperature range

Open bearing: -50 to +200 °C (-60 to +390 °F);
reduced load carrying capacity at temperatures above +120 °C (+250 °F);
bearings for higher temperature applications up to 300 °C, can be manufactured on request


Sealed bearings (limited by the seal material):

  • –20 to +80 °C (-5 to +175 °F) for inch RS seals
  • –30 to +130 °C (-20 to +265 °F) for metric RS seals with a bore diameter d < 320 mm
  • –35 to +100 °C (-30 to +210 °F) for metric RS seals with a bore diameter d ≥ 320 mm
  • –55 to +110 °C (-65 to +230 °F) for LS seals

The operating temperature range of the grease used to lubricate the bearings must also be taken into consideration.

SKF Explorer steel/steel radial spherical plain bearings
Dimension standardsMetric bearings:
ISO 12240-1:1998
  • GE series → dimension series E
    (GEM series: non-standard (extended) inner ring width, otherwise same dimensions as GE series)
  • GEH series → dimension series G

Inch bearings in the GEZ series:
ANSI/ABMA Std. 22.2-1988 (except for the inner ring width in the GEZM series)

Tolerances
Metric bearings in the GE, GEH and GEM series:
ISO 12240-1:1998 (table 1)

Inch bearings in the GEZ, GEZH and GEZM series:
ANSI/ABMA Std. 22.2-1988 (table 2)
Outer ring tolerances apply to conditions before fracture and surface treatment.
Accordingly, inner ring tolerances apply to rings before surface treatment.

Radial internal clearance

Normal as standard
Check availability of C2 (smaller) or C3 (larger) prior to ordering.


Values:

metric bearings:
ISO 12240-1:1998 (table 3)

inch bearings (table 4)


Materials

Inner and outer rings: high grade carbon chromium steel, hardened, ground and phosphated;

LS-seals: acrylonitrile butadiene rubber (NBR) (table 5)


Permissible operating temperature range

-45 to +110 °C (-50 to +230 °F)



Maintenance-free radial spherical plain bearings
Dimension standardsMetric bearings:
ISO 12240-1:1998
  • GE series → dimension series E
  • GEC series → dimension series C
  • GEH series → dimension series G
  • GEP series → dimension series H

Inch bearings in the GEZ series:
ANSI/ABMA Std. 22.2-1988

Tolerances
Metric bearings:
ISO 12240-1:1998 (table 1)

Inch bearings:
ANSI/ABMA Std. 22.2-1988 (table 2)
For the TX and TXG3 designs, outer ring tolerances apply to dimensions before fracture.

Radial internal clearance, preload

Steel/PTFE sintered bronze sliding contact surface: (table 3)

Steel/PTFE fabric sliding contact surface, metric sizes: (table 4)
Steel/PTFE fabric sliding contact surface, inch sizes: (table 5)

Steel/PTFE FRP sliding contact surface: (table 6)


Bearings with sliding contact surface combination steel/PTFE sintered bronze and steel/PTFE fabric and d ≤ 110 mm or d ≤ 4 in., either have an internal clearance or a slight preload (negative clearance) depending on their design. Therefore, these bearings can only be provided with an upper limit for bearing internal clearance. The lower limit must be assessed by the frictional moment, resulting from the preload (negative clearance).

Materials

Bearing rings and lining (table 7)

Seals (table 8)

Permissible operating temperature range
Table 7
If the load carrying capacity of the bearings is to be fully exploited, the temperature range must be narrowed. Depending on the application, it is possible to operate at temperatures above the upper limit for brief periods. For additional information, contact the SKF application engineering service.


SKF logo