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Submersible sphere made by LadishFeb 13, 2011 (Milwaukee Journal Sentinel - McClatchy-Tribune Information Services via COMTEX) -- Before research vessel Alvin can dive to the most extreme depths of the ocean, it needed to make a stop in Cudahy. The world famous submersible received a new titanium sphere -- the shell that houses the vessel's crew and equipment -- made at Cudahy-based Ladish Co. This summer, that sphere will be tested to determine whether the 47-year-old Alvin is able to explore 98% of the world's ocean bottom, giving scientists greater insights into sea life and geologic activity. Only trenches in the ocean floor would be much deeper, said Kurt Uetz, manager of the Alvin upgrade project at the Woods Hole Oceanographic Institution in Cape Cod, Mass. The $40 million makeover, funded by the National Science Foundation, is scheduled to be finished in 2015. It includes the titanium sphere, advanced electronics, better lighting and an increased payload capacity for the research vessel. Ultimately, Alvin will be able to stay down longer -- up to 12 hours -- and dive to 6,500 meters rather than 4,500 meters. That's more than 4 miles deep. The submersible, owned by the U.S. Navy and operated by Woods Hole, has been credited for some of the world's most memorable deep-sea discoveries, including hot volcanic vents on the ocean floor that changed the way scientists thought about how life could exist. In 1986, Alvin gave the world some of the first detailed views of the sunken RMS Titanic. In 1966, it found a hydrogen bomb lost in the Mediterranean Sea. Having made 4,600 dives, Alvin is a "workhorse" for ocean exploration, Uetz said. In December, the undersea veteran was taken out of service to prepare it for a two-phase makeover. The new sphere, made from two huge titanium disks, is a key part of the upgrades. Ladish made the sphere from two, 11-foot diameter titanium pancakes which were then formed into two domes. Once forged, the domes -- which began as 35,000 pounds of titanium ingots -- were welded together using an electron beam. They are the largest titanium hemispheric domes ever made, according to the company. The completed sphere was shipped to Los Angeles in 2008, where it has been machined, welded and outfitted for testing this year. "Our part is done. Now we are just waiting for someone else to say they want one of those," said Doug Roberts, a Ladish vice president. More spacious interior The sphere was designed with input from more than 110 biologists, geologists, microbiologists, geochemists and engineers for greater efficiency and a little more comfort. Alvin's new crew compartment will have a much roomier interior, in addition to enhancing the vessel's dive capabilities. With the current vessel, a pilot and two scientists climb through a narrow hatch into the equipment-filled, 6-foot-diameter sphere. Once sealed inside, they have no room to stand up, no seats and no bathroom. For up to eight hours, they sit on thin pads on the floor and peer out windows, or viewports, the size of teacup saucers. The pilot drives while perched on a small metal box. The new sphere's interior volume has been increased about 19%. With seats, it will be a lot more comfortable, according to Uetz. "Instead of crouching on the floor of the sphere, scientists will now have adjustable benches giving observers the option of sitting, kneeling, or lying flat," Woods Hole said in a news release. The upgraded vessel will have five windows, a big improvement over the three tiny ones it has now. That will give scientists a better view of what's going on outside the vessel, including work with robotic arms collecting samples from the ocean floor. Spheres are used for the crew compartments in deep-sea research vessels because the shape best resists the crushing force of thousands of pounds per square inch, according to Woods Hole. Should Alvin dive to a depth of 6,500 meters, it will experience pressures about 650 times greater than those felt on the surface of the earth, according to Woods Hole. One-of-a-kind work Century-old Ladish was hired to build the new sphere -- last updated in 1974 -- because it specializes in handling expensive materials such as titanium. Some of the company's manufacturing methods are thousands of years old but produce some of the most sophisticated equipment in the world. The company has the world's largest isothermal press, which produces aircraft engine parts for companies including Rolls-Royce and General Electric Co. The press stands about 30 feet above the factory floor and extends 25 feet below it. Four massive tie rods, each weighing more than 10,000 pounds, support the high-tonnage machinery. Often the company handles one-of-a-kind work where a mistake could result in hundreds of thousands of dollars in wasted material. The biggest challenge with making Alvin's new sphere was putting all the variables into a computer model that would accurately predict what would happen on the factory floor, according to Ladish. "We could not afford to start it and fail," Roberts said. "In this case, we got almost exactly what the model told us we would get." Ladish can make ring forgings weighing up to 350,000 pounds with 28-foot diameters. It can make bigger seamless aluminum rings than anyone else, according to the company. The company has made spheres for NASA's space shuttles and intercontinental ballistic missiles. Often the products are designed around the company's capabilities. "You can ask for the world, but in the end you have to get it made somewhere," Roberts said. Ladish employees may never take a dive in Alvin, but they can add the sphere to their list of accomplishments. "It was something that no one else had done. It's what makes this job interesting," Roberts said. To see more of the Milwaukee Journal Sentinel, or to subscribe to the newspaper, go to http://www.jsonline.com. Copyright (c) 2011, Milwaukee Journal Sentinel Distributed by McClatchy-Tribune Information Services. For more information about the content services offered by McClatchy-Tribune Information Services (MCT), visit www.mctinfoservices.com. |