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Dravo

 Getting a ship design from preliminary drawings to laying the keel is generally measured in years.  The fact that the first LST was commissioned on 2 November 1942, was a major achievement.  The Dravo Corporation would subsequently achieve a production rate of one LST every 3-1/2 days.  The total time from laying of the keel to launch was about 2-months by the end of the war.  Dravo Corporation was an innovative shipbuilder who designed a system of transfer carriages to utilize its pre-assembly and hull-moving techniques to speed up production.  Dravo built 60 transfer carriages for use at other inland yards.  This decision was made in spite of the fact that the other yards would become state-of-the-art competitors in the post-war period.

 That gesture solved the problem of the production of  LSTs in the quantities required, and within a short time frame.  In general, many shipyards built ships of riveted construction, the prevailing method at the time.  The Dravo people proved that a strong ship could be built with the all-welded method of ship construction and passed their expertise on to several other inland manufacturing firms.  For the first time in history, midwest shipbuilding of ocean-going ships was a reality.  The Illinois, Ohio, and Mississippi rivers  became the conduit for the LSTís self-propelled travel to the Gulf Coast.

 The Dravo Corporation used an all-welded construction method of prefabricated sections and work-stagings.  Electric welding was an advanced technique in 1942, and Dravo drew on their industrial experience in river barge construction, among other skills.  They used clusters of generators on skids to provide power for the arc welders moving around the site, with suspended staging and other mass production methods.  The prefabrication included box sections of the main hull with plates tightly flanged at the edge for smooth lap joints, giving little resistance to the water.  Each section had lugs temporarily welded for jacking into position, where it was held by a screw bolt during the welding.  This tight construction made for a strong ship.  Even the washbasin supports, the bow door assemblies and hinges were welded.  On the upper superstructure, tubed guards were shaped and welded around the gun positions, preventing accidental fire into the shipís own decks or upperworks.