FF
FF is an abbreviation of Flat Face flange
More about FF flangesFFS
FFS is an abbreviation of Fitness For Service
More about FFSFoF
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.
