H
Half-inch Point
A point located at a distance from the theoretical point toward the heel equal in inches to one-half the frog number, and at which the spread between the gage lines is one-half inch.
Heartwood
Inner core of the tree trunk comprising the annual rings containing non-living elements, usually darker in colour than sapwood.
Heel End of Frog
The end of a frog that is furthest from the switch.
Heel Length
The distance between the heel end and the half-inch point of a frog measured along the gage line.
Heel Slope
The inclination produced by graduated risers in that part of the switch which reduces the elevation of the switch point (as the height of the risers decreases) toward the heel of the switch to match that of the running rails.
Heel Spread
The distance at the heel between the gage line of a switch rail and the gage line of stock rail (standardized at 6 1/4" for straight switches).
Heel of Switch
That end of a switch rail which is the farther from its point and nearer frog.
Horizontal Split Head
A horizontal progressive defect originating inside the railhead. Usually 1/4" or more below the running surface and progressing horizontally in all directions and generally accompanied by a flat spot on the running surface. The defect appears as a crack lengthwise on the rail when it reaches the side of the railhead.
A point located at a distance from the theoretical point toward the heel equal in inches to one-half the frog number, and at which the spread between the gage lines is one-half inch.
Heartwood
Inner core of the tree trunk comprising the annual rings containing non-living elements, usually darker in colour than sapwood.
Heel End of Frog
The end of a frog that is furthest from the switch.
Heel Length
The distance between the heel end and the half-inch point of a frog measured along the gage line.
Heel Slope
The inclination produced by graduated risers in that part of the switch which reduces the elevation of the switch point (as the height of the risers decreases) toward the heel of the switch to match that of the running rails.
Heel Spread
The distance at the heel between the gage line of a switch rail and the gage line of stock rail (standardized at 6 1/4" for straight switches).
Heel of Switch
That end of a switch rail which is the farther from its point and nearer frog.
Horizontal Split Head
A horizontal progressive defect originating inside the railhead. Usually 1/4" or more below the running surface and progressing horizontally in all directions and generally accompanied by a flat spot on the running surface. The defect appears as a crack lengthwise on the rail when it reaches the side of the railhead.
