Design considerations

For additional information about rolling bearings and adapter sleeves for FNL housings, refer to the product information for:
Typical shaft-bearing combinations
FNL flanged housings can accommodate bearings on an adapter sleeve on plain shafts.
Locating and non-locating bearing positions
FNL housings can be used for both the locating and non-locating bearing positions. The housings are machined standard for bearings in the non-locating position. Bearings in the locating position as well as CARB toroidal roller bearings must be secured in the housing with a spacing washer or one or two locating rings (fig. 1). Appropriate spacing washers and locating rings are listed in the product table. When a spacing washer or only one locating ring is used, it should be inserted on the cover side of the bearing. When two locating rings are used, one should be placed on each side of the bearing.
Load carrying capacity
The permissible radial loads for a flanged housing depend on the bearing, the breaking load of the housing and the strength of the attachment bolts. Guideline values for the breaking loads of the housings are provided in the product table. The permissible axial loads for a flanged housing are limited by the friction between the sleeve and shaft. Additional housing support When the housing is subjected to heavy radial loads, a stop or dowel pins should be used to relieve the load on the attachment bolts. A shoulder or a guide ring on the support surface engaging a centring recess can also be used. Whichever method is used, it should be sufficiently strong to accommodate the loads acting parallel to the support surface. Recommendations for the position and size of the holes to accommodate dowel pins are provided in table 1. Dimples cast into the housing flange mark the recommended positions.
Operating temperature

The permissible operating temperature is mainly limited by the seals (table 1) and the lubricant. For temperature limits of SKF bearings and lubricants, refer to the relevant product information.

The housing material does not set any additional temperature limits, except for very low temperature applications where impact strength could be a factor. The housing paint is heat resistant up to 80 °C (175 °F) material temperature or 100 °C (210 °F) ambient temperature. When temperatures outside the permissible range are expected, contact the SKF application engineering service.
Operating speed
The seals can limit the permissible operating speed. They are suitable for circumferential speeds of up to 8 m/s. The corresponding rotational speeds are listed in table 1. For speed limits of the bearing, refer to the relevant product information.
Attachment bolt recommendations

In typical applications, 8.8 class hexagon head bolts in accordance with ISO 4014:2011 can be used together with washers in accordance with ISO 7089:2000 or 7090:2000. SKF housings can withstand loads resulting from tightening the attachment bolts to the torque values recommended by bolt manufacturers (→ product table). They are valid for oiled, but otherwise untreated, thread surfaces.

If the bearing arrangement is subjected to heavy radial loads, it may be necessary to use stronger, 10.9 class bolts. SKF cannot guarantee that tightening to the recommended value will provide sufficient anchoring. Make sure that attachment bolts, dowels or stops, shoulder or guide ring can accommodate all occurring loads.
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