Patent Number: 039705170
Section: claims

1. A process carried out in a hot-cell which includes therein a chamber and means for drawing a partial vacuum within said chamber and an electronic-beam welding apparatus, comprising the steps carried out within said chamber and under partial vacuum conditions, of (a) filling a compressible inner container with granulated radio-active material, (b) applying said vacuum pressure to said material within said container, (c) with said welding apparatus, welding a first lid onto said container to seal same against radio-active leakage, and (d) placing said sealed inner container within a compressible outer container with a space defined between said containers and surrounding said inner container, (e) filling said space with liquid metal, and (f) welding a second lid onto said outer container to seal same, thus providing a container assembly and performing compaction on said container assembly, by applying a pressure upon said sealed outer container which being compressible applies pressure onto said liquid metal which transmits said pressure equally in all directions onto said inner container which being compressible compacts said radio-active material therein. 2. A process according to claim 1 wherein said liquid metal comprises lead or a lead compound. 3. A process according to claim 1 wherein said welding apparatus is an electron beam welding apparatus. 4. A process according to claim 1 wherein said compaction on said container assembly comprises applying pressure of at least 1000 bar and simultaneously maintaining said assembly at a temperature of at least 1200.degree.C. 5. In a process of compacting a granular radio-active material into a solid body, where said material is precompacted in a compressible inner container and sealed against radio-active leakage by welding under partial vacuum conditions, the improvement in combination therewith comprising the steps: (a) providing a hot-cell, (b) placing within said hot-cell said inner container, a larger compressible container and lid for same, and welding means operable within partial vacuum conditions, (c) placing said inner container within said outer container, with a space defined between said containers and surrounding said inner container, (d) filling said space with liquid metal, (e) drawing a partial vacuum within said hot-cell and welding said lid on said outer container to seal same, thus providing a container assembly, and comprising the further step of performing compaction on said container assembly, by applying a pressure upon said sealed outer container which being compressible applies said pressure onto said liquid metal which transmits said pressure equally in all directions onto said inner container which being compressible compacts said radio-active material therein. 6. A process according to claim 5 wherein said liquid metal is lead or a lead compound. 7. A process according to claim 5 wherein said compaction on said container assembly comprises applying pressure of at least 1000 bar and simultaneously maintaining said assembly at a temperature of at least 1200.degree.C. 8. A container of radio-active material which material has a theoretical density based upon the chemical compound thereof, and an actual density greater than 95% of said theoretical density made by the process defined in claim 5. 9. A process for compacting a granular radio-active material into a solid isotopic heat source, comprising the steps: (a) filling a compressible inner container with said granular radio-active material, (b) partially evacuating said filler inner container and (c) welding a first lid onto said inner container and thereby sealing same against radio-active leakage, (d) placing said sealed inner container into a compressible larger outer container, with a space defined between said containers, (e) filling said space with a pressure-transmitting medium, (f) welding a second lid onto said outer container and thereby sealing same against leakage of the pressure-transmitting medium, providing a container assembly and also providing a second seal against radio-active leakage from said inner container, (g) performing compaction on said container assembly by applying pressure with a hydraulic press onto said outer container while maintaining said inner container in a heated condition whereby said pressure is transmitted via said compressible outer container into said pressure-transmitting medium and thence into said sealed inner container which being compressible compacts said radio-active material therein.