Nace CP 1, Руководство по эксплуатации

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Underground Corrosion Control 3:3
CP 1 – Cathodic Protection Tester Course Manual
©
NACE International, 2000
02/01/05
Two-Component Liquid Resin Coatings
These coatings consist of a liquid resin, usually an epoxy, and a curing
agent. The two components are sprayed in the correct proportion onto the
pipe, usually in one or two coats to achieve a final thickness of 12 to 16
mils (0.304 mm to 0.406 mm ) . These coatings are also resistant to impact
and abrasion damage.
Girth Weld and Other Field Coatings
Welded joints, fittings, and other appurtenances must be coated in the field.
Various materials are used for this procedure including heat shrink sleeves,
hot- and cold-applied tapes, two-component liquid resins, coal tar mastics
and fusion bonded epoxy. The field coating selected must be compatible
with the adjacent coating and as durable as that on the structure itself.
Surface Preparation
Proper surface preparation is essential if the coating is to bond properly to
the metal. Each type of field coating will have a specific surface preparation
requirement that must be followed.
For all coatings, the surface must be clean and dry. Often this is
accomplished with power tools but in some cases abrasive blasting and
solvents is required.
Some coatings require a primer on the prepared surface prior to the
application of the coating. Primer application must be done in accordance
with the manufacturer’s specifications and must be allowed to dry to the
specified consistency before the outer coating is applied.
Application
Coatings may be hot or cold applied. The most common field coatings in
use today are liquid epoxies, heat shrink sleeves and various types of tape.
All coatings should be applied in accordance with the manufacturer’s
requirements.
Inspection Procedures
Initial Inspection
Surface preparation must be inspected to ensure adherence with the
specifications. Environmental conditions such as temperature, humidity and