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MIL-HDBK-1038
8.5
Welding. Welding procedures, materials, standards, and welder
qualifications are comparable to those of AWS. NCC requires all the necessary
certifications and other data for review and approval prior to start of work.
In some foreign countries U.S. government inspectors are available to monitor the
adherence to approved procedures and quality of workmanship and testing. American
Bureau of Shipping inspectors are also stationed in the major ship building
centers of some countries and may be commissioned to provide their services on
Navy crane projects.
8.6
Wire Ropes. Federal Specification RR-W-410 and Wire Rope Users Manual
contain a wide selection of wire rope constructions and sizes, and these are the
preferred choices for the majority of crane applications. There are non-routine
applications, however, that require specialty foreign designs for optimum
operation and service life. Examples of such specialty wire ropes are those
designed specifically for non-rotating characteristics, multi-layer spooling, and
resistance to abrasion and mechanical damage. The unique construction and metric
sizes of such ropes do not comply with those of RR-W-410 or Wire Rope Users
Manual. Such wire ropes may be used on Navy cranes, subject to NCC review and
approval of the specific applications.
It is common U.S. industry practice to groove sheaves for two wire rope
diameters. In selecting metric wire ropes for installation on new cranes with
such sheaves, the metric diameter must be within the limits of the wire ropes for
which the sheave is grooved. When the wire rope is to be installed on an older
crane (with sheave and hoist drum grooves configured for a specific U.S. produced
wire rope type) the sheave and hoist drum grooving must be considered to ensure a
satisfactory match with the wire rope, and NCC approval must be obtained.
8.7
Specialty Components. Some key components of cranes are produced only in
foreign countries or by U.S. subsidiaries of foreign countries in conformance with
foreign standards. The capacities or ratings of such components, and their
installation requirements, are converted to the English engineering units and
verified for specification compliance.
8.7.1
Common Components. Other foreign-manufactured standard mechanical and
electrical components, even though they have U.S. equivalents, may also be used on
Navy cranes. Their selection and sizing must be supported by engineering
calculations and other appropriate documentation, in the same manner as the
specialty components.
8.8
Exceptions. There are certain prohibitions on the use of components from
foreign sources. Such prohibitions are due to practical considerations either
susceptibility to counterfeiting or maintenance and timely support.
8.8.1
High-Strength Structural Bolts and Nuts. Structural bolts are critical
to the safety and integrity of the structures of all sorts, but are subject to
counterfeiting and misidentification. NCC policy is to prohibit the use of high-
strength structural bolts from foreign manufacturers.
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