ENS Event | |
|---|---|
18:00 Nov 8, 2006 | |
| Title | Defect Identified in Crane Brake Caliper Mounting Pin |
| Event Description | United States Enrichment Corporation (USEC) identified a defect in a Continental Brake Model No. 95400 crane hoist drum hydraulic brake caliper mounting pin (part no. 3954022). The firm that supplied the item was Continental Brake Equipment Company, Longboat Key, Florida. The item is a commercial grade item, dedicated for use as a Basic Component upon receipt inspection.
The defect involved errors in the machining of a groove which accepts a retaining ring to hold the caliper mounting pin in place. Specifically, the grooves were machined too shallow and too narrow to properly accept and hold the retaining ring. The result is that during use the retaining ring may dislodge from the pin, allowing the pin to loosen. This happened in the certificate holder's C-315 facility during use. A loose mounting pin can result in the brakes not performing its function as a hoist brake to prevent the uncontrolled lowering of a UF6 cylinder. Per the faxed USEC report: "Failure of the crane hoist resulting in the drop of a cylinder containing liquid UF6 is identified in the PGDP accident analysis as resulting in off-site uranium exposures exceeding the guidelines established for determining a substantial safety hazard. USEC has inspected all subject mounting pins in service and on-hand. All defective mounting pins were removed from service or shelves. USEC has not communicated with other specific purchasers or licensees but they recommend that users of cranes with similar brakes inspect the subject caliper pins for engagement. |
| Where | |
|---|---|
| Paducah Gaseous Diffusion Plant Paducah, Kentucky (NRC Region 2) | |
| License number: | GDP-1 |
| Reporting | |
| 10 CFR 21.21 | |
| Time - Person (Reporting Time:+1391.57 h57.982 days <br />8.283 weeks <br />1.906 months <br />) | |
| Opened: | Steve Toelle 17:34 Jan 5, 2007 |
| NRC Officer: | Pete Snyder |
| Last Updated: | Jan 5, 2007 |
| 43080 - NRC Website | |
Paducah Gaseous Diffusion Plant with 10 CFR 21.21 | |
WEEKMONTHYEARENS 430802006-11-08T18:00:0008 November 2006 18:00:00
[Table view]10 CFR 21.21 Defect Identified in Crane Brake Caliper Mounting Pin 2006-11-08T18:00:00 | |