MIL-HDBK-1110
(6) Heat-Shrinkable Tapes - Heat-shrinkable tapes of
polyolefin provide tight bonding to pipes. They are shrunk in
place by heating at 300 to 400 degrees F. Their relatively high
cost limits their use to special areas such as joints.
5.6.1.2
Immersed Steel Fuel Lines. Immersed pipes lines can be
in fresh or salt water, near the surface where they are exposed
to ultraviolet (UV) light or deep where UV light is not of
concern. Further, some pipe lines are exposed to abrasion from
particulates and debris in the water. A coating that has been
successful in some applications is the three-coat epoxy system
described for steel fuel tank interiors in par. 5.3.1. Vinyl
coatings are effective where there is abrasion. The pipe lines
can also be cathodically protected.
5.6.1.3
Aboveground Fuel Lines. Aboveground fuel lines can be
coated much the same as fuel tank exteriors described in
par. 5.3.2. A petrolatum paste/tape system has also been used
very effectively in protecting fuel lines under piers. The
system can be applied by hand over wire-brushed steel. It is
very easy to repair when damaged.
5.6.2
Steel Water Distribution Lines. Steel water
distribution lines should be coated as described for steel fuel
distribution lines in pars. 5.6.1.1, 5.6.1.2, and 5.6.1.3,
depending upon the environment, buried, immersed, or aboveground.
Although buried steel water distribution lines do not present the
same level of environmental hazard as do buried steel fuel lines,
it is recommended that they be cathodically protected, as well as
coated. For steel water distribution lines that are buried but
not cathodically protected, use the three-coat epoxy-polyamide
system described for steel fuel tank interiors in par. 5.3.1.
5.7
Communication Towers and Other Tall Structures. The
military has thousands of communication towers of various sizes
and configurations in many geographical and climatic regions.
The tower designs and initial treatments of the steel
construction materials often vary from site to site and within
the same site. These variable factors often cause problems in
obtaining cost-effective painting of the towers.
Many towers require either a painted pattern of
alternate aviation orange and white markings for daytime
visibility, or lighting (strobe for high towers). Requirements
for marking and lighting are described in detail in Federal
Aviation Administration (FAA) Advisory Circular 70/7460-1G.
Compatibility of coatings can be determined as described in par.
5.6.2. The use of painted patterns over zinc-coated structures
is a better choice over lighting for long-term use and operation
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