F

Fasteners
Joint bars, bolts, clips and spikes.

Fish-Plate
A short steel joint connector lapping a rail joint, secured to the side of two rails with bolts.

Flange-Rail
A rail turned on its side and installed with its head against the web of the running rail to establish a flangeway for wheels through highway crossings or paved areas.

Flangeway
The open way through a track structure which provides a passage way for wheel flanges where two tracks cross.

Flangeway Depth
The depth of the wheel flange passageway or the vertical distance from the top of the tread surface to the top of the filler or separator introduced between the tread portion and the guard portion of a track structure.

Flangeway Width
The distance between the gage line and the guard line of a track structure that provides a passageway for wheel flanges.

Flare
A tapered widening of the flangeway at the end of the guard line of a track structure as at the end of a guardrail or at the end of a frog or crossing wing rail.

Flashbutt Weld
An electric weld process which electrically forges two rails together.

Flowed Head
A rolling out of the metal on top of the head of a rail toward the sides without showing any indication of a breaking down of the head structure.

Foot Guard
A filler for the space between converging rails to prevent a person's foot from becoming accidentally wedged between the rails.

Frog
A track structure used at the intersection of two running rails to provide support for wheels and passageways for their flanges, thus permitting wheels on either rail to cross the other.

Frog Angle
The angle formed by the intersecting gage lines of a frog.

Frog Number
The number of units of length in which the spread is one unit.

Frog Point
The part of a frog lying between the gage lines extending from their intersection to the heel end.