Mechanical Parts; Inspection; Antenna - Andrew 4.9-Meter ESA Operating And Maintenance

Mechanical Parts

Inspection

Antenna

Clean mechanical parts by first removing dust, dirt, and other loose contaminants with a
scraper, stiff brush (bristle or wire in the case of rust or other corrosion), or cloth or com-
pressed air at 25 to 40 psi. Any accumulated imbedded dirt, corrosion, grease, or oil
deposits that require further cleaning may be removed with a bristle or wire brush and a
cleaning solvent such as trichlorethylene or equal. After cleaning, allow cleaned parts to
dry for 10 to 15 minutes before placing the equipment into operation.
The frequency of inspection is contingent upon the user's individual standards and the
operational environment in which the earth station is located. However, a visual inspec-
tion of the earth station components should be performed at least semi-annually. Where
there are no established wear limits, perform a visual inspection to locate worn or dam-
aged parts which could cause improper functioning of the earth station. It is recommend-
ed that the mechanical and electrical inspection be performed on the assembled or par-
tially disassembled equipment to determine the extent of disassembly required prior to
completely disassembling a suspected malfunctioning component or module. In the
absence of any special inspection requirements, operational tests are the most effective
means in isolating parts and assemblies requiring further inspection. Any condition
noted during inspection that may preclude continued proper operation of the earth sta-
tion prior to the next scheduled inspection should be noted. The discrepant condition
should be corrected (repaired or replaced) immediately or at the conclusion of the
inspection procedure.
Inspection of the antenna conforms generally to standard visual inspection procedures
performed on electromechanical equipment. In addition to these procedures, perform
the following checks and visual inspections for the specific conditions noted:
•
Inspect all wiring and cables particularly the network to enclosure and enclosure to
mount interfaces for discoloration and burned insulation, moisture entry, corrosion, dirt,
breaks, security of connection, and other signs of deterioration. Examine connections for
dirt, corrosion, and mechanical defects. Check for loose or broken lacing and cut,
abraided, frayed, brittle, and cracked insulation.
•
Examine connectors for corrosion, broken inserts and stripped threads. Check con-
nector shells for distortion and dents, and contact pins for bends, misalignment or other
deformities. Check connector inserts for cracks, and carbon tracking, burns or charring
indicating arc-over.
•
Check all electrical component for dirt, cracks, chips, breaks, discoloration, and other
signs of deterioration and damage. A discolored, blistered, or burnt condition is evidence
of overload.
•
Inspect the azimuth and elevation jackscrew boots for security of attachment at both
ends, for abrasion, tears, cuts, brittleness and other damage that may expose the
jackscrew to the environment (water, dust, etc.). Minor repairs can be made with RTV-
108 silicone rubber sealant.
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Preventive Maintenance