MIL-HDBK-1005/6
Section 2:
TRACKAGE COMPONENTS
Rails. The rail section for new track and for extensive rail
2.1
replacement projects shall conform to 135-pound CR (crane rail) control-cooled
standard. For locations and arrangements of portal crane trackage and rail
supports, see sources under Additional Criteria above. Use welded joints
whenever possible.
Turnouts and Crossings. A turnout is an arrangement of switch
2.2
points and frog, which divert the crane from one track to another. Special
track fittings, such as switch points and frogs, are required for the
wide-gage systems which use double-flanged wheels. These fittings must
provide double flangeways for crane wheels, where crane rails diverge or
intersect. In addition, special fittings are needed where wide and standard
gage trackage intersect or where wide and standard gages are accommodated on
three rails, with one rail shared by both gages. Where both cranes and
railroad cars utilize a common rail (three-rail system), the other railroad
rail should be placed between the crane rails. Standard fittings shall be
used on all new and replacement construction and only on level grade.
2.2.1
Switches (Two-Rail System).
Switches. Special switches are required in a crane track turnout
2.2.1.1
for double-flanged crane wheels. The double-tongue switchpoint consists of
two rail heads on each tongue. A flangeway is therefore provided on both the
gage side and field side of the running rails.
Material.
Either cast or fabricated designs may be used.
2.2.1.2
Cast.
See NAVFAC Standard Drawings Nos. 1403326-27.
a)
Fabricated.
See NAVFAC Standard Drawings Nos. 1404035-37.
b)
Wheel Loads. See "Wheel Loads for Locomotive and Portal Cranes" in
2.2.1.3
NAVFAC MIL-HDBK-1025/1, Piers and Wharves. Minimum criteria: 100 kip
vertical, 15 kip lateral, on 3 foot 6 inch centers.
2.2.2
Frogs (Two-Rail Track System).
Rigid Frogs. The use of rigid frogs is permissible only in cases
2.2.2.1
where the actual frog angle is greater than that shown in Figure 2 for the
actual crane rail radius. They shall be designed for double-flanged wheels.
Turnable Frogs. This type of frog is preferable for all
2.2.2.2
locations, and its use is mandatory in locations as indicated by Figure 2.
Materials.
Either cast or fabricated designs may be used.
2.2.2.3
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