Electric Boat has put millions of dollars into the building where workers assemble submarines.
Monday, the company cut the ribbon on a freight elevator, one of the investments the shipyard has made to begin building one nuclear submarine a year in 2011 in Groton.
The company has put more than $19 million into Building 260, where workers assemble submarines.
It expects to save $80 million in man hours and pass the savings on to its customer, the U.S. Navy, as part of a contract it won last year to build eight Virginia class submarines here and in Virginia..
Along the future USS Missouri, John Casey, president of Electric Boat, said new doors would keep the weather off the ship and off the workers.
The elevators will also improve health and safety, he said.