control or a manual 90 degree twist drain valve, mounted on the low end
of the reservoir. The remote control for the drain valve shall be on
the curb side of the semitrailer and shall be accessible to personnel
from the standing or kneeling position. The foundation brake assemblies
shall be not less than 12.25 by 7.5-inch size, cam or wedge type. The
brake lining shall be of the metallic type having nonfading character-
istics when subjected to heat and to water immersion. The lining shall
be class Code FE in accordance with Regulation V-3 of the Vehicle Equip-
ment Safety Commission. The lining shall be selected by the supplier
and shall be of a standard size as listed in the Automotive Data Book
of the Friction Materials Standards Institute, Inc. The lining seg-
ments shall be not less than 3/4-inch remind thickness. The brake
lining shall be installed on the shoes by the use of hardened steel
bolts and nuts, as recommended by the lining manufacturer. All metal
surfaces enclosed by the brake drum and the dust shields shall be
coated with lacquer-primer conforming to MIL-P-46093 or TT-P-664.
Wedges, pins, cams, rollers, and anchors shall be coated with Preserv-
ative oil conforming to MIL-L-21260, grade 2.
188.8.131.52 Brake lines. The brake lines shall be routed within the
protection of the semitrailer framing and shall be secured by cushioned
support clamps spaced at intervals not greater than 3 feet. Through-
frame connections or grommets used in conjunction with clamps shall be
required where lines pass through sheet metal or framing members. The
routing and connection locations shall facilitate replacement of the
lines from bulk supply. Not less than 5 inches of slack in flexible
air hose shall be provided at each of the relay emergency valve con-
nections to permit interchange of the various makes of MS53004 valves.
The hose ends of these lines shall be identified by markers conforming
to MS39020 near each fitting. Brakeline components shall conform to
(a) Flexible air hose - MIL-H-3992, type I, class 1 or 2.
(b) Rigid air line - SAE J844, copper tubing.
(c) Fiitings - SAE J512, heavy-duty airbrake, compression
Rote: At the supplier's option, flexible air lines conforming to SAE J40,
SAE 40 R2, type E or F, may be furnished in lieu of the flexible air
hose and rigid air lines specified in (a) and (b) above-
3.13.6 Vehicular electrical system. The screening unit shall be
equipped with a waterproof, 24-volt vehicular electrical system for
service and blackout night travel. Except as specified herein, the
electrical system shall be in accordance with the following requirements: