ASTM A 123/A 123M after drilling is completed and shall not be painted.
2.4.1.3
Structure Foundation Design
Structure foundation design shall be as indicated. If the manufacturer's
standard structures differ in dimensions from those shown, foundation
design shall be modified to suit the structures provided, at no additional
cost to the Government. Maximum earth-bearing pressure shall be calculated
at [191.5] [_____] kPa [4000] [_____] psf.
2.4.2
Conductors
**************************************************************************
NOTE: Justify selection of copper or aluminum,
based upon an analysis using life, environmental,
and cost factors. Refer to TM 5-811-1/AFM 88-9
Chapter 1 regarding substation conductors and buses.
**************************************************************************
Conductors shall be [aluminum-conductor-steel-reinforced (ACSR)] [copper]
[high-strength aluminum alloy] with sizes as indicated, and shall comply
with IEEE Std 525. Span lengths shall be based on a limiting deflection of
1/150 for spans having two supports and 1/200 for spans having three
supports, under maximum wind, ice, and short-circuit loadings, including
suitable allowances for any taps. Where required, larger or stronger bus
shall be installed to maintain specified deflections for the indicated span
lengths. Other bus shapes for electrical conductors may be used if detail
drawing submittals indicate equivalent ampacity and strength. Short
connections, consisting of bare stranded conductors of equivalent bus
ampacity, may be used between incoming line conductors and buses or between
buses and equipment. Copper flexible braid or aluminum strap expansion
couplers, as required to match the bus material, shall be installed in bus
runs where required to allow for expansion and contraction, and at all
connections to transformer bushings.
2.4.2.1
Suspension Insulators
**************************************************************************
NOTE: Refer to TM 5-811-1/AFM 88-9 Chapter 1 for
guidance regarding substation insulators.
**************************************************************************
Suspension insulators shall be provided for dead-end incoming line
conductors. Suspension insulator strings and string supports shall provide
a mechanical strength exceeding the ultimate strength of each dead-end
conductor. Minimum ratings of suspension insulators shall be not less than
ANSI C29.2 Class [52-3] [or] [52-4]. Each suspension string shall have not
less than [_____] insulators in tandem.
2.4.2.2
Apparatus Post Insulators
Apparatus post insulators shall be provided to support conductors, and
their mechanical strength shall exceed the ultimate strength of the
conductor supported and, where necessary, high-strength or ultra
high-strength insulators shall be provided. Minimum ratings of apparatus
post insulators shall be not less than ANSI C29.9, Technical Reference
Number [_____].
SECTION 16311A
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