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NOTE: If possible, always install a repair section at
low-level. Removal and direct installation of standard sections
can be used to shift the position of the section needing
replacement. If high-level repair is mandatory, platforms
allowing work at a 16-ft (4.9 m) height are needed at eight
supports. A working platform is also needed at the center
of the section being replaced. This platform must allow work
up to 8 ft (2.5 m) away from the cable. CAUTION: THE REPAIR SECTION IS NOT INTENDED TO REPLACE A DAMAGED SECTION WHICH REQUIRES BENDING TO INSTALL. IN ADDITION, THE STRAIGHT SECTION IT REPLACES MUST BE FOLLOWED (IN THE DIRECTION OF THE ANTENNA) BY TWO OR MORE STRAIGHT SECTIONS. When damage occurs, determine if the section meets the requirements for replacement by a repair section. If it does not, then locate the closest section (in the direction of the antenna) that does. Then this section, the damaged section(s), and all intervening sections are removed. New sections are installed plus the final repair section. 5.5.1 Remove Damaged Cable Section(s) Remove the damaged section(s) as follows: WARNING: DEPRESSURIZE THE TRANSMISSION LINE before attempting any transmission line repair. 1. Use a reciprocating power saw to cut completely through the outer and inner conductors of the damaged section nearest the antenna. Cut along one of the outer conductor corrugations about 8 ft (2.5 m) from the flange at its ANT end. Make another cut, starting in a corrugation about 8 ft (2.5 m) from its TX end flange. 2. If the section is supported at low levels, remove the U-bolts from all hangers supporting the cut segment. Remove the segment from the hangers and discard. For high-level or transition supports, install the lifting assemblies from the set (#221755) at each support and attach nylon chokers, ropes, and pulleys to the cut segment before removing the U-bolts. Lower the cut segment and discard. NOTE: Save the U-bolts and all hanger hardware for reassembly of the hanger. 3. If this is the only section requiring replacement, proceed to Step 4. Otherwise, cut the adjacent cable section -- toward the transmitter -- about 8 ft (2.5 m) from its TX end. Remove this segment as described in Step 2 above. Continue this process until all of the damaged sections are removed. |
NOTE: If one of the sections that requires removal is
undamaged, it can be removed intact. Remove the 8-ft (2.5 m)
segment on the transmitter end of the transmission line per
Steps 4 and 5 below. Then remove the undamaged cable sections
as described in Section 5.6. 4. Support the 8-ft (2.5 m) segment of damaged cable on the transmitter side and, if necessary, remove the U-bolt from the hanger. Save the U-bolt and hanger hardware. Then, remove the flange hardware and slide the outer conductor back about 4 inches (102 mm). Discard the hardware. 5. Separate the inner conductor joint by first attaching the inner conductor tool (#220335) to the undamaged inner conductor. Hold this tool in place, and use the driver-ring torque wrench (#220047) to loosen the driver ring. Turn the driver ring until the inner conductors are completely separated. Discard the segment. |