Abstract: A Co-base alloy including, by weight, 0.03-0.10% C, not more than 1.0% Si, not more than 1.0% Mn, 20-30% Cr, 15-23% Ni, 3-10% W, 5-10% Ta and 0.05-0.7% Zr, is used as a welding material. A gas turbine nozzle has a crack repaired with a multi-layer weld using the Co-base alloy and a gas turbine for power generation employs the nozzle.

Abstract: A method for controlling a gas turbine combustor which comprises nozzles for injecting fuel into a combustor and which serves to combust the fuel with air in a combustion chamber so as to rotatively drive a gas turbine by combustion gas compressed as a result of combustion of a fuel, wherein the ratio of a flow rate of fuel supplied into the combustor to a flow rate of air supplied into the combustor is changed in accordance with at least one of the states of fuel, air and rotational frequency of the turbine.

Abstract: To provide a combustion apparatus and a controlling method therefor which are capable of preventing the flame-out and backfire of the flame of a premix burner and the increase of the NOx concentration attributable to the change of the calorific value of the fuel, the amount of air supplied to the premix burner is so controlled as to achieve a low NOx within the range in which the premix burner effects a stable combustion in accordance with the calorie of the fuel supplied to the combustion apparatus, and a change of the output of the combustion apparatus attributable to this control of the amount of air is compensated by the control of the amount of the fuel supplied to the diffusion burner.

Abstract: A fuel supply amount is controlled while the load of a gas turbine is changed so that the fuel supply amount is shifted to a fuel supply amount in accordance with the changed load. A fuel supply control valve is operated at high speed during an initial stage and operated at a lower speed as the fuel supply amount necessary for the changed load is reached. Therefore flameout of a combustor is prevented without increasing the number of revolutions of the gas turbine over a certain upper limit.

Abstract: A combustion apparatus comprises a combustor liner forming a combustion chamber, and a swirler for introducing a fuel gas into the combustion chamber in the form of a swirl. The combustor liner has an air film forming device provided on the wall thereof and capable of forming a film of cooling air on the inner peripheral wall of the combustor liner so as to protect the combustor liner from the hot combustion gas in the combustion chamber. The air film forming means is formed such that the flowing direction of the air forming the film becomes the same direction as the swirling direction of the combustion gas, so that the film of the cooling air is not broken by the hot combustion gas.

Abstract: A burner comprises at least one swirl member for mixing a fuel with an air previously to burning of the fuel, and at least one eddy generating device which is arranged in a flow of a mixture of the fuel and air to generate an eddy flow in the flow so that the eddy flow maintains a shape of a flame of the burned fuel. The at least one eddy generating device is arranged apart from a downstream end of the swirl member by a fixed sufficient distance so that the shape of the flame maintained by the eddy flow is prevented from moving toward the downstream end of the swirler member.

Abstract: A method and apparatus for controlling a temperature of a turbine casing and a turbine rotor in a gas turbine, which method and apparatus enables a maintaining of an optimum gap at a tip end of the rotor blades of the gas turbine over an entire operating range by independently controlling the amounts of heat energy supplied to a space of the turbine casing and the turbine rotor.

Abstract: A gas turbine cooling apparatus is disclosed in which a flow sleeve is provided to surround a combustor liner and a tail pipe substantially over their full length. A group of small holes for impinge-cooling an outer wall of the tail pipe are formed in a region of the flow sleeve close to a turbine. Further, opening portion for introducing cooling air are provided closer to the combustor liner than the small holes. Thus, the outer wall of the tail pipe and the wall of the combustor liner are cooled by the cooling air flowing between the tail pipe, the combustor liner and the flow sleeve.

Abstract: Stator blades and rotor blades are cooled by discharge air discharged from an air compressor coupled directly with gas turbine. A signal of the compressor discharge pressure and a signal of turbine exhaust gas temperature are obtained, and cooling air flow is controlled based on these signals.