2.6.4.4
Slip Joints
Fabricated from tubular sheet metal sections. Provide outer tube with
formed steel flat bar clamps. Where required or indicated, provide a chain
or other means to fix relative longitudinal position of outer and inner
joint sections.
2.6.5
Gaskets
2.6.5.1
Elastomer Buna N
Sheet, 3 mm 1/8 inch thick, conforming to ASTM D 2000, Type 2BG410B14.
2.6.5.2
Elastomer Chloroprene
Sheet, 3 mm 1/8 inch thick, conforming to ASTM D 2000, Type 2BE410B14.
2.6.5.3
Rubber
Sheet, 3 mm 1/8 inch thick red or black, natural, reclaimed, synthetic
rubber or mixture thereof, conforming to ASTM D 1330.
2.6.6
Protective Coating Materials
2.6.6.1
Baked Unmodified Phenolic
MIL-V-12276, Type II.
2.6.6.2
Epoxy Coating
Conform to MIL-P-23236, Type I, Class 1 or MIL-P-24441 system, Formula 150
green primer 0.076 mm 3 mils, Formula 151 haze gray 0.076 mm 3 mils, and
Formula 152 white 0.076 mm 3 mils.
2.6.6.3
Inorganic Zinc Coating
SSPC Paint 20, Type I-C (Self-cure type).
2.6.6.4
Galvanizing Repair Paint
2.6.7
Sealants
2.6.7.1
Elastomeric
Sealant specified in these specifications or referenced standards as
elastomeric or without further qualification, shall be silicone,
polyurethane, polysulfide, polyisobutylene, or acrylic terpolymer suitable
for the service. For sealing of nongasketed duct joints during fabrication
or assembly, sealant shall be polyurethane, acrylic terpolymer or
polysulfide. Sealants shall conform to the following:
a.
Silicone: Conforming to FS TT-S-001543, single component type,
not requiring primed substrate, with manufacturer published
estimated life of 30 years and a maximum 5 percent shrinkage when
cured.
b.
Polyurethane:
Conforming to FS A-A-1556, Type 2, Class A, single
SECTION 15801N
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