FUEL INJECTOR NOZZLE WITH PREHEAT SHEATH FOR REDUCING THERMAL SHOCK DAMAGE

摘要

The operating life of a fuel injector nozzle (10) for a gasifier is prolonge d by shielding the fuel injector nozzle (10) with a preformed protective insulating sheath (70) before the fuel injector nozzle (10) is installed inside a preheated reaction chamber of the gasifier. The thermal insulating sheath (70) has low thermal conductivity and is placed around the fuel injector nozzle body. The thermal sheath (70) can also be positioned to cove r a downstream end (16) of the fuel injector nozzle (10) that includes a nozzl e portion (40). The thermal insulating sheath (70) is supported by ceramic rop e, solder or metal wire and is gradually consumable in the environs of the reaction chamber immediately after the fuel injector nozzle (10) is installe d. Before the thermal sheath (70) is consumed, it moderates the temperature ris e rate of the fuel injector nozzle (10) while the fuel injector nozzle (10) is being installed in the gasifier.