 |
The Manhattan Project Heritage Preservation Association, Inc. "Preserving, Exhibiting, Interpreting and Teaching the History of the Manhattan Project" |
|
| Home | Site Map | Contact Us | Feedback | Mission |
Manhattan Project History
Clinton Engineer Works (Oak Ridge)
Y-12 Plant (Page 2 of 3)
Electromagnetic Separation of Uranium 235
Operator: Tennessee Eastman Company (Kodak)
February 18, 1943
|
Lawrence and his colleagues continued to look for ways to improve the electromagnetic process. Lawrence found that hot (high positive voltage) electrical sources could replace the single cold (grounded) source in future plants, providing more efficient use of power, reducing insulator failure, and making it possible to use multiple rather than single beams. Meanwhile, receiver design evolved quickly enough in spring and summer 1943 to be incorporated into the Alpha plant. Work at the Radiation Laboratory picked up additional speed in March with the authorization of the Beta process. With Alpha technology far from perfected, Lawrence and his staff now had to participate in planning for an unanticipated stage of the electromagnetic process. While the scientists in Berkeley studied changes that would be required in the down-sized Beta racetracks, engineering work at Oak Ridge prescribed specific design modifications. For a variety of reasons, including simplicity of maintenance, Tennessee Eastman decided that the Beta plant would consist of a rectangular, rather than oval, arrangement of two tracks of thirty-six tanks each. Factoring this configuration into their calculations, Lawrence and his coworkers bent their efforts to developing chemical processing techniques that would minimize the loss of enriched uranium during Beta production runs. To make certain that Alpha had enough feed material, Lawrence arranged for research on an alternate method at Brown University and expanded efforts at Berkeley. With what was left of his time and money in early 1943 Lawrence built prototypes of both Alpha and Beta units at Berkeley for testing and training operating personnel. Meanwhile Tennessee Eastman, running behind schedule, raced to complete experimental models so that training and test runs could be performed at Oak Ridge. But in the midst of encouraging progress in construction and research on the electromagnetic process in July came discouraging news from Oppenheimer's isolated laboratory in Los Alamos, set up in 1943 to consolidate work on atomic weapons. Oppenheimer warned that three times more fissionable material would be required for a bomb than earlier estimates had indicated. Even with satisfactory performance of the racetracks, it was now possible that they might not produce enough purified uranium 235 in time. Lawrence responded to this crisis in characteristic fashion: He immediately lobbied Groves to incorporate multiple sources into the racetracks under construction and to build even more racetracks. Groves decided to build the first four as planned but, after receiving favorable reports from both Stone & Webster and Tennessee Eastman, allowed a four-beam source in the fifth. Convinced that the electromagnetic process would work and sensing that estimates from Los Alamos might be revised downward in the future, Groves let Lawrence talk him into building a new plant - in effect, doubling the size of the Y-12 complex. The new facility, Groves reported to the Military Policy Committee on September 9, would consist of two buildings, each with two rectangular racetracks of ninety-six tanks operating with four-beam sources. Shakedown at Y-12 During the summer and fall of 1943 the first electromagnetic plant began to take shape. The huge building to house the operating equipment was readied as manufacturers began to deliver everything from electrical switches to motors, valves, and tanks. While construction forces now totaled more than 15,000 people, another 5,000 operating and maintenance personnel were hired and trained. Then between October and mid-December, Y-12 paid the price for being a new technology that had not been put through its paces in a pilot plant. Vacuum tanks in the first Alpha racetrack leaked and shimmied out of line due to unforeseen tremendous magnetic forces, welds failed, electrical circuits malfunctioned, and operators made frequent and costly mistakes. Most seriously, the magnet coils shorted out because of rust and sediment in the cooling oil. Groves arrived on December 15 and shut the entire racetrack down. The coils were sent back to Allis-Chalmers with hope that they could be cleaned without being dismantled entirely, while measures were taken to prevent recurrence of the shorting problem. The second Alpha track now bore the weight of the electromagnetic effort. In spite of precautions aimed at correcting the electrical and oil related problems that had shut down Alpha 1, the second Alpha fared little better when it started up in mid-January 1944. While all tanks operated at least for short periods, performance was sporadic and maintenance could not keep up with the electrical failures and defective parts. Like its predecessor, Alpha 2 was a maintenance nightmare. Alpha 2 eventually produced about 200 grams of twelve-percent uranium 235 by the end of February 1944, enough to send samples to Los Alamos as well as feed the new Beta unit but not enough to satisfy estimates of weapon requirements. The first four Alpha tracks did not operate together until April, a full four months behind schedule. While maintenance improved, output was well under previous expectations. The opening of the Beta building on March 11, 1944 led to further disappointment. Beam resolution was so unsatisfactory that a complete redesign was required. To make matters worse, word spread that the K-25 gaseous diffusion process was in deep trouble because of its ongoing barrier crisis. K-25 had been counted upon to provide uranium enriched enough to serve as feed material for the Beta tracks. Now it would be producing such slight enrichment that the Alpha tracks would have to process K-25's material, requiring extensive redesign and retooling of tanks, doors and liners, particularly in units that would be wired to run as hot, rather than as cold electrical sources.
|
IF
YOU SEE A YELLOW "ENTER" BUTTON ABOVE, PLEASE DO NOT "CLICK" ON IT.
THIS WILL TAKE YOU TO A GAMBLING SITE WHICH WAS ADDED TO OUR WEB SITE
WITHOUT OUR PERMISSION!
This web site is growing by 150 pages per month - Click
