Gas injector and gas injection direction adjusting method

摘要

There is provided a nozzle section having a nozzle for injecting gas and a spherical portion composed of a nozzle nut part and a spherical base end portion, respectively on its front end portion and base end portion. There is provided a nozzle case for supporting the spherical portion so as to make an outward gas injection direction of the nozzle adjustable. The spherical base end portion and the nozzle nut part are provided so that they are separated from one another by the rotation of one of the nozzle and nozzle nut part about the axis of the longitudinal direction. The nozzle section which has been adjusted to have a gas injection direction is fixed from the side of the nozzle, thereby simplifying adjustment of a gas injection direction at the nozzle section by eliminating conventionally required additional operations.