At Newport News Shipbuilding, an iconic 50-year-old gantry crane comes down
By DAVE RESS | Daily Press (Newport News, Va.) | Published: October 2, 2020
NEWPORT NEWS, Va. (Tribune News Service) — They switched Newport News Shipbuilding’s giant new crane at dry docks 10 and 11 from its extension cord to a permanent power supply this week. They’ll load the last big pieces of the old green gantry crane that it replaced onto barges over the next several days.
And with that, the shipyard is nearly at end of a seven-year, $60 million project.
The old green crane was designed for a different age — of what manager of crane engineering Jim Kelly calls “stick-built” ships, or moving individual steel plates and pieces into a dry dock for assembly.
These days, shipbuilders at the dry docks wrestle modules — major sections of ships, like the 750-metric ton forward section of a carrier’s main deck that contain machinery spaces for diesel generators, or the portion of a flight deck that houses command-and-control facilities, pilot ready rooms and includes a jet blast deflector and components of the gear system that slow Navy jets when they land.
So the yard wanted a crane that can move those modules into a dry dock for assembly, like giant Lego blocks, without the complex rigging the old green crane needed to spread those huge weights over its aging steel frame.
Taking the old green crane down means its replacement can now plug its electric motors, winches and computerized controls into the nearby power connections, instead of the temporary feed off a spare circuit at a substation in the North Yard.
The new crane also stands taller — some 400 feet above the bottom of a dry dock, which means masts and antennas of carriers in the yard for multiyear refueling and complex overhauls will no longer need to be removed to allow the crane’s loads to move along the length of a ship.
Its controls facilitate much more precise positioning of the modules, too, Kelly said.
But getting it to Newport News and setting it up was no simple matter.
The yard’s dry docks 10 and 11, for instance, date to World War II, “and I didn’t want to do anything to overload the sides of the dry docks, or the bottoms," said Brian Jones, who led the core team of eight who spearheaded the project, working with colleagues from across the yard.
Since the main horizontal girder of the new crane — the piece with the 16-foot high “Newport News Shipbuilding” lettering — along with the control cab and other elements that sit at its top weighed in at 1,750 tons, that was a real worry.
It meant the way the yard erected the old green crane in 1969, working from a pier jutting out into the James River, wasn’t going to work. Finding space on the bustling yard, however, was also a head-scratcher.
“The biggest challenge was logistics,” Jones said. “You think you’ve got some space and five minutes later, someone puts something there.”
Some of those items are huge. Most are a top priority for one or another of the shipyard’s several simultaneous carrier or submarine construction or overhaul projects.
In the end, the work of erecting the new crane and taking down the old one meant camping out in one of the most heavily trafficked areas of the two-and-a-half mile long shipyard, Jones said.
That’s the space near 50th Street where shipbuilders hustle parts and tools from the south yard shops up to the north yard along Shipyard Drive, and where the yard’s internal railroad tracks also ran.
If that wasn’t enough, Jones ended up needing to dump 800 tons of rock to drive new pilings and lay new concrete pads to provide a solid enough base for work on the new crane.
And as it turned out, be the base for dismantling the old green crane.
The same steel towers and eight powerful hydraulic jacks used to lift the new crane’s girder and other components high into the air were key to disassembling the old green crane.
Each jack had 54 wire ropes running through a powerful hydraulic ram, each rope capable of holding 15 tons, and designed to grab objects in much the same way as those woven bamboo finger trap toys that tighten their hold if you try to pull free.
They held the green crane’s girder in place as contractors carefully cut out sections of its support legs. Then, those jacks lowered the girder so it rested on the supports that remained, before the whole process was repeated.
It took about a week and a half to do — but months to plan, and work out all the steps for the process to go without a hitch. Nobody wanted to see several-hundred-ton crane parts falling hundreds of feet.
“If it looks easy when you do it, that tells you you’ve done the engineering right, you’ve done your planning right,” Kelly said.
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