A Link and Some Other Info
Hello Pete. During my career as a U.S. Navy officer specializing in engineering, I saw a number of shipyards and intermediate repair facilities.
Here is a link to the website for Bath Iron Works (BIW) Corporation:
http://www.gdbiw.com/
For one year and one day, I had a hand in supervising the complete overhaul of a Knox Class Frigate there. The current photos are a lot more colorful than what I remember from '78-'79.
Most of the cranes were traveling cranes on tracks set at the pier edges. Many items, like large pumps or motors were brought from the "Inside Machine Shop", where they'd been overhauled or rebuilt, on flatbed trucks and craned to holes cut in the side of the ship for purposes of removal/re-installation of this gear. The hole usually had scaffolding outside it. Fully 3/4ths of the cranes were of this type. The IHC #7777 Gantry Crane would be a good starting point if the girder work is fine enough. Model Power #424 should also work. Sheepscot 31232 looks good, but has the wrong type of structure above the machinery housing or cab. Wheeled or truck mounted cranes might be used in the materials receiving yard for off-loading specialty metals shipped in by truck (example--boiler tubes). The main materials (steel)facility would probably have one of the overhead traveling cranes like the Walthers model produced for their backshop.
Structures would mainly be metal or some masonry, seldom wood (fire hazard). Alpine Models #700-1 (a Walthers number) would make a good outside machine shop or valve shop. Pikestuff might also be a good source. many of these contained overhead cranes.
Do not forget fences, guards, and security offices--a shipyard is a very secure facility.
Finally, BIW had a monster specialty crane that could reach almost anywhere in the yard. It could be seen at least twenty minutes away on I-95. This was a one-of-a-kind of Japanese design and manufacture. On a very clear day, you could see it not long after leaving Portland northbound.
I hope this all helps!
--Stu--