Standard housing design

Designs and variants

FNL flanged housings are non-split housings that have:
  • a triangular flange for sizes up to and including 13 (fig. 1)
  • a square flange for larger sizes (fig. 2)
FNL housings are supplied with a cover:
  • for shaft ends (fig. 3), designation suffix A
  • for through shafts (fig. 4), designation suffix B
Housings with a centring recess
  • can be centred on a shoulder, provided either by machining the wall or by attaching a guide ring to the wall (table 1)
  • are supplied on request
  • are identified by the designation suffix P, e.g. FNL 511 BP

When the housings are centred on a shoulder, the attachment bolts are not subjected to shear forces.

Housings with a grease escape hole
  • have the hole machined in the cover (fig. 8)
  • are supplied on request
  • are identified by the designation suffix V, e.g. FNL 511 AV
Housing material
  • grey cast iron
Paint, corrosion protection

FNL flanged housings are painted black (RAL 9005). The paint:

  • is a water based alkyd/acryl paint
  • protects the housing in accordance with ISO 12944-2, corrosivity category C2 (i.e. exterior atmospheres with low level of pollution, interior atmospheres where condensation may occur)
  • is not affected by most lubricating or engine oils, cutting fluids or alkalescent washing chemicals
Housings can be repainted with most water or solvent based 1- or 2-component paints. Unpainted surfaces are protected by a solventless rust inhibitor.
Dimension standards
FNL flanged housings:
  • are not standardized either nationally or internationally
  • are dimensionally interchangeable with the earlier 7225(00) housings
Sealing solutions
FNL flanged housings are supplied with low-friction, double-lip grease seals (fig. 9.) The information in table 2 should be used as a guideline and does not substitute for testing a seal in its application.

If additional seals are needed, they can be ordered separately with the prefix TFL followed by a number indicating the size, e.g. TFL 511.

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