After removal from the spent fuel storage bay, spent nuclear fuel can be stored in above-ground Dry Storage Containers (DSC's).  DSC's are loaded with fuel underwater in the spent fuel bay, and then capped with a lid.  Prior to transfer of the DSC's to an area where they can be dried and have the lids permanently welded into place, a temporary lid clamp must be installed to ensure that the DSC contents will be safely retained during all required handling and transportation activities.

In addition to being contracted to build a prototype Dry Storage container, ODIM Numet routinely supplies DSC lid clamps.  The clamps measure 33" high by 95" wide by 107" long, and weigh 4500 lbs.  An actuation mechanism swivels a series of dogs inward from each side of the clamp to engage the top flange of the DSC and hold its lid in place. The DSC design requires large full penetration welds for its fabrication, but to function as required in this extreme safety critical application, accurate mating tolerances must be met to ensure a tight fit between the DSC and its lid. As final machining after welding is not practical for a weldment of this size, Numet developed extensive custom fixturing and a carefully sequenced welding procedure, to ensure that the tight tolerances required across the clamp are not lost due to the warpage that typically occurs from large welding heat input into this type of configuration.  ODIM  has designed and supplied various versions of this equipment to meet varying requirements of specific customer applications.