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 MIL-HDBK-1038
Section 3:
3.1
Cranes. Standard commercial crane types, such as locomotive and
revolving cranes, are designed to crane industry specifications, and are optimized
for specific applications. They may be used at their rated or reduced capacities,
at the discretion of the using activity.
3.1.1
Locomotive Cranes. Locomotive cranes are powered by diesel engine-
generator sets and are self-propelled. They are available with free over-side
rated capacities of up to 55 tons and up to 150 tons when set on outriggers.
Standard commercial locomotive cranes are designed to comply with ANSI/ASME B30.5,
Mobile and Locomotive Cranes.
3.1.2
Pedestal and Revolving Gantry Cranes. These cranes are designed as
standard commercial upperworks units for mounting on tubular pedestals or other
support structures. The booms may be of the fixed-length lattice or of the box-
section telescopic design. They are designed for road transportability and ready
installation on various support structures, and of necessity, lack some of the
customary maintainability and service life prolonging features of Navy portal and
floating cranes.
Pedestal cranes, which are intended for offshore service on oil rigs, are
designed to comply with American Petroleum Institute Specification API 2C. They
may be powered either with an onboard diesel engine or from a remote electric
power source. The drives are hydraulic or direct mechanical type. Drive
machinery on some standard designs is only partially enclosed by a machinery
house, but the exposed equipment is required to have other means of adequate
protection from the corrosive marine environment. Stainless steel hydraulic lines
and special exterior paints are among standard options.
Revolving gantry cranes are similar in design to the pedestal cranes, but
may not comply with Specification API 2C and are not optimized for the marine
environment. They are normally installed on traveling gantries (portal bases).
3.2
Monorail Systems. Monorail installations utilize the same hoists and
hoist/trolley units as the underrunning cranes. Monorail layouts may be straight,
with curves, open or closed loops of patented track. The suspension must be
either laterally braced flexible type or rigid. Standard track switches, both
electrically or manually operated, are available to permit hoist/trolley units to
transfer between adjacent sections of the monorail layout. The switches include
interlock mechanisms for positive track alignment and automatically activated
forks (stops) to prevent a hoist/trolley unit from rolling off an end of the
track. Standard commercial monorails are designed to comply with ASME B30.11,
Monorails and Underhung Cranes.
Electrically powered hoist/trolley units on curved track require rigid
electrification curved to follow the track at a fixed distance. Standard
electrification hardware is available to permit smooth crossing of collector shoes
at the switches to maintain uninterrupted electric power. Motion control is
normally from a control station suspended from the hoist/trolley unit.
Alternatively, the motions may be controlled by remote means, such as infrared or
radio signals.
3.3
Line Handling Mechanisms. Various line handling (hauling) mechanisms
such as capstans, windlasses, and winches, are standard commercial products
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