Patent Number: 054815762
Section: description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In describing preferred embodiments of the present invention illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the invention is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. Referring now to FIGS. 1-3, there is shown a vibrating assembly 10 in accordance with the present invention for vibrating an ice basket 20 of a pressurized water reactor (not shown). Vibrating assembly 10 comprises left and right vibrators 100a and 100b and a bracket 200 for operatively connecting vibrators 100a and 100b to the rim or top ring 20a of an ice basket 20. Bracket 200 includes a horizontally-extending first armature portion 210 having first and second downwardly-extending ends 212 and 214 and a middle 216 intermediate first and second ends 212 and 214. First and second clamps 220 and 222 extend downwardly from first armature portion 210 at first and second ends 212 and 214. First and second clamps 220 and 222 are welded or otherwise fixed at notches cut out of first and second ends 212 and 214, respectively. An attachment portion 230 extends vertically upwardly from first armature portion 210. Attachment portion 230 is unitarily formed in a single, generally T-shaped piece with first armature portion 210. Preferably, first armature portion 210 and attachment portion 230 are formed from a 3/4" thick piece of metal plate. Junctions 232 between attachment portion 230 and first armature portion 210 are smoothly rounded to distribute forces concentrating at junctions 232 due to vibrations. A hole 234 is drilled proximate the top center of attachment portion 230 to accommodate a lifting shackle (not shown) used in placement and removal of assembly 10. Bracket 200 further includes a horizontally-extending second armature portion 240 pivotably connected to the bottom of a first armature portion 210. Second armature portion 240 has first and second outwardly-extending ends 242 and 244 and a middle 246 intermediate first and second ends 242 and 244. Third and fourth clamps 250 and 252 extend downwardly from second armature portion 240 at first and second ends 242 and 244, respectively. Third and fourth clamps 250 and 252 are pivotably connected to first and second ends 242 and 244 in a manner to be described in detail hereinafter. Each of first and second clamps 220 and 222 and third and fourth clamps 250 and 252 has top and bottom surfaces 260 and 262, inner and outer surfaces 262 and 264, and opposed end surfaces 268. A groove 270 extends vertically upwardly from each bottom surface 262 and across each of clamps 220, 222, 250, and 252 from one to the other of end surfaces 268. Grooves 270 are arcuate, having a radius matching the curvature of rim 20a of ice basket 20. An internally-threaded cylindrical bore 272 extends inwardly from each inner surface 264 so as to be in communication with each groove 270. A socket head cap screw 274 or similar fastener is inserted into each bore 272 with a locking washer 276 interposed between its head and inner surface 264 in a conventional manner to secure rim 20a in groove 270 in the same manner as a set screw. As will be appreciated by those of ordinary skill in the art, bore 272 can equally well extend from outer surface 266 into communication with groove 270. The manner in which third and fourth clamps 250 and 252 are connected to second armature portion 240 will now be described. First and second ends 242 and 244 of second armature portion 240 are provided with first and second vertically-extending slots, respectively. Socket head cap screws 286 or similar fasteners are inserted through slots 282 and 284 and into bores 280 of third and fourth clamps 250 and 252, with locking washers 288 conventionally interposed between the screw heads and top surfaces 260 of third and fourth clamps 250 and 252. The lateral positions of screws 286 in first and second slots 282 and 284 are adjustable. The angular position of grooves 270 of third and fourth clamps 250 and 252 with respect to the longitudinal axis of second armature portion 240 are also adjustable by pivoting third and fourth clamps 250 and 252 relative to the longitudinal axis of second armature portion 240 before tightening screws 286. In order to connect second armature portion 240 to first armature portion 210, first armature portion 210 is provided with an internally-threaded bore 290 extending upwardly at its center bottom, while second armature portion 240 is provided with a bore 292 through its center. With bores 290 and 292 aligned, a socket head cap screw 294 or similar fastener is inserted through bores 292 and 290 to pivotally connect first and second armature portions 290 and 292 at their respective middles 216 and 246. Again, a locking nut 296 is conventionally interposed between the screw head and the bottom of second armature portion 240. Preferably, left and right vibrators 100a and 100b are air powered vibrators such as CCR 5500 Martin Vibrotor.TM. vibrators, and attachment portion 230 is approximately 5" wide by 12" high to accommodate the mounts 110, such as Cradle lug clamp mounts (part no. 22817) required to clamp vibrators 100a and 100b to the sides of attachment portion 230. Vibrators 100a and 100b and their mounts 110 are bolted on each side of attachment portion 230 in the vertical position. This arrangement provides counter rotation of vibrators 100a and 100b and enhances the vibrating efficiency. When in operation, the vibrating forces are directed down along the sides of ice basket 20. Also preferably, plant air at 60-80 psig is utilized with two air separator-dryers (not shown) to operate vibrators 100a and 100b, producing a total output of approximately 25 CFM. Although this arrangement has proven successful in experimental trials, increasing the total output to 30-50 CFM is also contemplated. It is hypothesized that the additional air supply would increase the vibrating forces transferred to each ice basket 20 and therefore shorten the time interval required to vibrate each ice basket. In use, as indicated above, a lifting shackle (not shown) is attached to attachment portion 230 through hole 234 in order to position vibrating assembly 210 over the top of a selected ice basket 20. Once vibrating assembly 10 is properly oriented with rim 20a of ice basket 20 properly seated within grooves 270, cap screws 274 are tightened to secure vibrating assembly 10 to ice basket 20. Screw 294 fastening second armature portion 240 to first armature portion 210, and screws 286 fastening clamps 250 and 252 to second armature portion 240 are then tightened to complete the installation of vibrating assembly 10. Once all of the screws have been checked for tightness, the air supply can be turned on to start vibrators 100a and 100b. Referring now to FIG. 4, in order to optimize the vibrating capabilities of vibrators 100a and 100b, ice basket 20 is pulled from the top utilizing either an overhead hoist or a Port-a-Power.TM. attached to a fabricated A-frame, depending on the overhead clearance available. Both methods utilize a load cell and the maximum tension is maintained at less than or equal to 3000 pounds pressure. Ice basket 20 also is pushed from the bottom utilizing a Port-a-Power.TM. with a load cell to maintain a compression of less than or equal to 4000 pounds pressure. The combination of tension and compression during the vibrating maximizes the vibrations along the surfaces of ice basket 20. Modifications and variations of the above-described embodiments of the present invention are possible, as appreciated by those skilled in the art in light of the above teachings. For example, hold down clamps may be used in certain situations to fit over ends 212, 214, 242, and 244 and to extend through the basket 20 below the top ring to prevent the assembly 10 from pulling off of the top ring. It is therefore to be understood that, within the scope of the appended claims and their equivalents, the invention may be practiced otherwise than as specifically described.