| 摘要 |
1497793 Cufting nozzles BOC INTERNATIONAL Ltd 17 Oct 1975 [24 Oct 1974] 46061/74 Heading F4T A nozzle for use in the exothermic cutting of metal has a central cutting-oxygen passage 22, and one or more flammable gas passages 18 for providing a preheating flame, passage 22 having a section 24 of minimum cross-section whose surface is roughened, and is spaced from the end of the nozzle by bores 26 of increasing diameters. Oxygen flows through passage 14, and fuel gas flows through passage 16 and mixing occurs in chambers 12 so that the gas issuing from passages 18 is ignited to provide preheating flames. The cutting oxygen flows through passages 22, 24, 26, and 28. The roughness in section 24 is produced by screw-cutting. |
