Paragraph 2.2.54 includes standards for several outside and inside
paint systems. The standard gives general information on the suitability of the paint
systems under varying conditions, as well as information about surface preparation,
paint-film thickness, and procedures for applying paint. Paint systems used for painting
tanks on military installations should meet or exceed the requirements established in
Cathodic Protection for Steel Tanks. Design standards and specifications
for cathodic and impressed current protection of steel water tanks may be found in
pars. 2.3.19 and 2.3.20. For general information on corrosion of exposed and buried
metals, refer to par. 2.2.19. The primary reference for cathodic protection is MIL-
HDBK-1136 (par. 188.8.131.52).
Limitations. Cathodic protection is limited to structures in contact with an
electrolyte, such as soil or water. In steel elevated water storage tanks, only the inside
surfaces of the riser and the submerged bowl can be protected. Protect the outside of
the tank from atmospheric corrosion by some other means.
Pipelines. Because pipes are normally buried and out of sight, pipeline
maintenance is often neglected. Components of a pipeline maintenance program
include inspection, leak detection and repair, flushing, pigging, slip-lining, cement-
mortar lining, wrapping, and cathodic protection. These and other aspects of pipeline
maintenance are covered in pars. 2.1.4, 2.2.41, and 2.3.18.
Protective Coatings. To supplement the information provided above
about corrosion protection for specific equipment, this paragraph offers general
General Information. The prevention of corrosion and surface
deterioration is standard maintenance practice in waterworks. Protect all exposed
surfaces, whether external or internal. Protective coatings and linings may be
nonmetallic or metallic. The former includes paint, enamel, bitumen, cement, plastic,
and rubber. Metallic coatings include zinc, aluminum, and lead. Other corrosion-
control treatments are used on metal equipment surfaces that cannot be painted.
Cathodic protection is used where electrolytic corrosion occurs.
Paint Protection. Surface coating with paint is the most general method of
corrosion prevention. Try to select paint to meet the existing conditions; the choice
depends on whether or not the equipment or structure is indoors or outdoors.