Most of the energy expended so far on the new Tacoma Narrows bridge has been focused on its bottom.
For more than a year, crews have been guiding the bridge's massive foundations, as big as 20-story apartment buildings, to their final resting places in the Narrows floor, 200 feet below sea level.
At the same time, and with far less fanfare, Tacoma foundry workers have been building parts of the new bridge that will be perched on its very top.
The Atlas Castings & Technology steel foundry in Tacoma's Nalley Valley is making the span's "saddles" - SUV-sized hardware that will cradle the two main suspension cables and keep them aligned.
On Friday, Atlas workers poured molten steel to create the first of four tower saddles, which will end up atop the bridge's 509-foot towers - nearly as tall as the Space Needle. Four more saddles will guide the cables into their anchorages on shore.
The eight saddles, 20 to 36 tons of solid steel machined to tolerances measured in thousandths of an inch, are remarkable geometric forms.
But they're also remarkable for another reason: They're being made in Washington state.
In this era of outsourcing, most of the steel for the bridge comes from other countries.
The milelong bridge deck and the 5,500 tons of wire in the main cables are being manufactured in South Korea, the 264 suspender cables in Canada, the steel shoes that anchor the cable strands in Britain and the two miles of cable wrapping in Japan.
"Our competition for the saddles contract was primarily from overseas," said Duane Britschgi, Atlas' president and CEO. "As it happened, this fit us very well."
Engineers at Tacoma Narrows Constructors, the Bechtel/Kiewit partnership building the bridge, say they're delighted to have one of their suppliers so close, not only because of the good will that comes from providing local jobs, but also because bridge engineers and foundry workers are close enough to talk in person.
"It's a 10-minute drive to the Atlas shop," said Shawn MacCormack, the TNC engineer riding herd on the saddles. "When we have to review any technical issues they have, it's so much simpler to be able to do that face-to-face rather than on the phone or by e-mail."
Atlas is delighted as well. The saddles are not the biggest castings the foundry has worked on, but they're close. Neither TNC nor Atlas would divulge the exact amount of the saddles contract. The new bridge is a public project, but TNC got the job on the basis of a total price and is under no obligation to say how much it pays its subcontractors.
"Let me put it this way," said David Caldwell, Atlas' vice president of sales. "We're extremely happy to have it."
Caldwell said about 5 percent of Atlas' 300-person work force is dedicated to the 15-month-long project. Because of it, the company added 15 employees, including molders, core makers, welders, grinders and helpers.
Last month, when Atlas workers poured molten steel into the first saddle mold, a dozen top officials from TNC, Atlas and the state Department of Transportation gathered to watch.
With sparks flying like tracer rounds at his feet, Transportation Secretary Doug MacDonald watched entranced.
"This is a wonderful process to watch," he said. "It's great to see the bridge construction producing more work in Tacoma.
"This job is in Tacoma because these people successfully bid against competitors all over the world," MacDonald said. "It shows that a Washington company and its workers can win in the world marketplace for highly specialized manufacturing."
BRIDGING THE INDUSTRIAL AGE AND HIGH TECHNOLOGY
Atlas has a division in Chehalis and a small presence in China, but the main foundry is spread over 18 acres along Center Street in the heart of Tacoma, where it's been for 105 years.
The foundry includes 500,000 square feet of covered floor space, but it manages to keep a low profile in the city.
Most Tacoma residents know it only as a place where, taking the Wilkeson Street shortcut under Highway 16 to Costco and the Tacoma Mall, they occasionally have to stop for workers or forklifts crossing in the middle of the block.
Atlas' history is obvious inside the plant, where heavily muscled laborers swing hammers, great ladles of molten metal swing from hooks on cranes and the clang of steel on steel deafens visiting ears.
Squint and it's easy to imagine being in the 19th century. And, in fact, parts of the Atlas factory are that old. One of the main production buildings dates back to 1899, the year the company was founded to make iron castings for the logging industry.
During the 20th century, Atlas stayed put as the city grew around it. In that time, the foundry's products and technical capabilities grew increasingly sophisticated.
Atlas built steel parts for the defense industry during World War II, moved into castings for the oil and chemical industries in the 1950s and started making parts for the nuclear industry in the 1970s. In the 1980s, it made high-strength alloy castings for the U.S. Navy's ships and submarines - ranging from hatch covers to power generation turbines.
Now it is capable of producing more than 100 alloys, including stainless steel and nickel-based mixes.
Atlas' Industrial Age ambiance is punctuated with high-tech touches. Designers pore over computers that flip and turn virtual models inside out. In a section of the production area surrounded by concrete walls 6 feet thick, a massive linear accelerator shoots X-rays through 20 inches of solid steel, seeking out flaws and discontinuities.
Some of Atlas' work is classified. On a recent walk through the plant, Britschgi wouldn't identify some of the big, oddly shaped steel forms on the foundry floor.
"You can read about them in Tom Clancy's novels," he said.
While Atlas' main location has not changed in the past century, its ownership has - a half-dozen times. In 2002, Britschgi, Caldwell and 10 other local mangers teamed up with a Houston investor and bought the foundry from its parent company, TIC United Corp., then mired in bankruptcy.
Now, the owner/managers are trying to make a go of it in an economic environment that relentlessly grinds away at the American steel industry. Britschgi said only three, possibly four, foundries in the country are capable of taking on a job as big and technically complex as the Narrows bridge saddles.
He attributes Atlas' survival to its adaptability, a reputation for quality and its wide range of capabilities.
"We're unusual because we're a true jobbing foundry," he said. "We can make castings of all kinds, rather than specializing in a particular product."
With its new owners at the helm, Atlas is in a growth mode. According to Britschgi, the company grossed $37 million last year and will gross more than $40 million in 2004.
"Our goal is $75 million in 2010," he said.
SIMPLE, BUT COMPLEX
Building the bridge saddles is a complicated business. It begins with calculating the weights and stresses likely to be placed on the new bridge by the weight of the bridge structure and the load put on it by traffic and such variables as wind and ice.
On the new Narrows bridge, the 21-inch main cables will be composed of 19 bundles of 464 wires, each the thickness of a pencil. As the bundles pass through the saddles, vertical dividers will keep them stacked and aligned, like hair passing through the teeth of a comb. At the saddles, the weight of the bridge will be transferred onto the towers.
The cables won't move in the saddles, but they must strike exactly the correct angle to match the path of the cables. The saddles must be strong and precise, and they have to be resistant to corrosion from exposure to wind, rain, saltwater and hot sun.
"The job they do isn't very complicated, but there's some very complex engineering that goes into them," said Dennis Engel, project manager for the Department of Transportation.
The tower saddles will weigh 36 tons when finished. That's too heavy for the crane TNC will use to build the towers, so Atlas is pouring them in two 18-ton pieces, which will be hoisted to the top and then bolted together.
"If it were all in one piece, we would have had to get a bigger crane," MacCormack said.
The "splay" saddles, which will align the main cables as they enter the 90-million pound anchorages buried at each end of the bridge, did not have the same weight restriction because the land-based cranes have a greater lifting capacity.
Those saddles, each cast in a single 20-ton chunk, will be bolted to the top corners of the anchorages where they will intercept the cables as they descend from the towers.
As the cables cross the splay saddles, they'll fan out into their 19 bundles, which will wrap around steel embedded in concrete at the rear of the anchorage.
Bridge designers specified that the saddles would have to be able to withstand a force of 60,000 pounds per square inch without changing shape.
To accomplish that, Atlas is using a nickel, chromium and molybdenum alloy - a strong, corrosion-resistant mix.
In a neat instance of recycling, the foundry was able to use as part of the raw material the massive anchor chains that held the bridge caissons in place as they were being constructed.
The big chains, each link as large as a man's torso and weighing 205 pounds, are being melted down in Atlas' electric arc furnace at a temperature of about 3,000 degrees.
In all, more than 57 tons of chain will be used in the saddles.
Temperature control is a critical aspect of casting steel, Britschgi says. The rate at which the molten metal cools affects strength, and, with large, irregularly shaped pieces like the saddles, a good deal of effort has to be taken to make sure the cooling is consistent.
Using computer simulation software called Magmasoft, Atlas engineers devised efficient ways to feed liquid steel to the saddle molds to make sure there are no voids and to control shrinkage.
Specifications produced by engineers were transferred to working drawings, which patternmakers used to make full-size replicas of the saddles out of wood.
The wood patterns are encased in sand hardened with a chemical binder. When the pattern is removed, the cavity left behind forms the mold.
When the molten steel is the right temperature, it is tipped out of the furnace into a pouring ladle lined with ceramic and positioned over the mold.
Wearing heavy gloves, heat-resistant jackets and face shields, workers called "pour-off guys" align the ladle over the inlets in the mold, then open nozzles on the ladle's bottom, sending the 2,800-degree liquid gushing into the mold at 370 pounds per second.
"It's a little frightening at first," said Charles Jones, 51, who has been a pour-off guy since 1972. "But when you see how organized it is, you stop worrying.
"You get used to the heat," he said. "It gets to be pretty routine."
In about two weeks, when the raw saddle casting is cool enough, workers break open the mold, revealing a rough piece that looks like something that might have fallen from outer space.
The rough casting is then inspected, blasted and machined to its final dimensions, a process that takes several months and entails removing about half of the metal originally poured into the mold cavity.
All eight of the saddles are due to be delivered to TNC in early 2005.
The process is a tricky one at every step, Caldwell says. As he points out, there are 242 variables in the molding and pouring stages alone.
"There are a thousand ways to make a casting wrong," he said, "and only one way to make it right."
When the tower saddles are finished and bolted into place at the top of the new bridge, Chris Gilbert, another Atlas pour-off guy, says he's going to be proud to drive under them.
"This is bigger than just us," Gilbert said. "It extends from the office down to the sand guys, to the melters and to us who poured it.
"When it's up there on that bridge, everybody in this foundry will have had a part in that."
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Rob Carson: 253-597-8693
rob.carson@thenewstribune.com
