FF
FF is an abbreviation of Flat Face flange.
The Flat Face flange has a gasket surface in the same plane as the bolting circle face. Flat Face
does not feature the raised face of heavy duty flanges such as ASME B 16.5 for example. Applications
using flat face flanges are frequently those in which the mating flange or flanged fitting is made
from a casting.
FFS
FFS is an abbreviation of Fitness For Service.
Fitness For Service assessments help determine if equipment is safe and fit for continued operation.
It prevents breakdowns, minimizes risk and avoids costly repairs.
FoF
FoF is an abbreviation of Flange of Face.
This terminology is used when dimensions have to be given with respect to face of flange.
FFW
FFW is an abbreviation of Field Fit Weld.
A field fit weld indicates that the designer has foreseen that the piping may need adjustment in
the field so has added an extra length of pipe at a buttweld fitting or flange. The pipe end will
be bevelled and welded on site after the installer determines the correct dimensions.