Andrew 3.7-Meter Earth Station Antenna manual

Jackscrews/Motors

Gear

Motor/Housing Fill

Drain

Requirements

remove any old lubricant to prevent an excessive build-up. Remove indicated access plugs from square tube weldment and apply lubricant to panning frame tube assembly and corresponding thrust pads. Securely replace access plugs in square tube weldment. Be certain to remove any protective caps and clean off each lubrication fitting prior to injecting fresh grease. The elevation and azimuth jackscrew assemblies are equipped with a grease fitting and corresponding pipe plug on opposite sides of the jack housing. Remove the appropriate pipe plug and fill with with grease until lubricant seeps from the pipe plug opening. Replace and securely tighten pipe plug.

The following is a list of the lubricant characteristics:

• Mobil Temp SHC32 A non-soap hydrocarbon fluid type grease. Operating tempera-

ture range is -65 degrees to 350+ degrees Fahrenheit (-54 degrees to 177+ degrees Celsius).

•Mobil SHC624 A low temperature synthetic oil for worm gear reducers.

Operating temperature range is -40 degrees to 125+ degrees

Fahrenheit (-40 degrees to 52+ degrees Celsius).

• Lightning Grease	A grease lubricant containing molybdenum disulfide. Operating
	temperature range is -85 degrees to 300+ degrees Fahrenheit
	(-29 degrees to 149+ degrees Celsius).

Periodically inspect lifting screws on jackscrew assemblies to ensure adequate lubrica- tion. Loosen Jackscrew boot clamps to expose the lifting screw assembly. Fully extend jackscrew assembly being careful not to exceed preset mechanical limits. Brush thin coating of Mobil SHC32 grease on exposed lifting screw. Replace boot and attach corre- sponding boot clamps. If lifting screw is rusty, remove existing lubricant with solvent and wire brush rusted area. Rinse with solvent and apply fresh grease.

Peiordically inspect and remove dust or dirt deposits from the motor housings to avoid hindering the heat exchange with the ambient air. Slight dirt accumulation on the air vent screw through splash oil cannot be avoided; however, keep vent screw clean to ensure proper pressure compensation.

Lube points 2 and 4, shown in Table 5-1, require removal of the indicated drain plugs and collecting/measuring the amount of SHC624 drain oil using measuring cup. The specified amount of oil must be added to the gear motor/housing (after installing the drain plug) via the fill/vent plug opening using supplied funnel. Addition of the oil requires use of an appropriate filling utensil. Use of a modified level stick will not cor- rectly gauge the appropriate amount of oil in the gear housings.

85 Preventive Maintenance