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 gas turbine combustor having a fuel injection nozzle for diffusion combustion disposed in a central portion of the combustor and an annular premixed nozzle disposed in an outer peripheral portion of the fuel injection nozzle for injecting a mixed gas of fuel and air. The annular premixed nozzle includes an annular premixing chamber and a plurality of premixed fuel nozzles for injecting fuel into the annular premixing chamber. The annular premix nozzle is divided by a partition (108) to form a plurality of premixing chambers each adjacent to the fuel injection nozzle for diffusion combustion. Each of the premixing chambers includes at least one of the premixed fuel nozzles. A mechanism is provided for supplying fuel to a predetermined number of the premixing chambers in a low load operation of the gas turbine and for supplying fuel to all of the premixing chambers in a high load operation.

Abstract: A gas turbine combustor is provides with a stabilizer at a downstream side of a premixing device for premixing and supplying fuel and air into a combustion chamber. The stabilizer has a cylindrical part extending axially from an upstream end thereof to a downstream end and a stabilizing part at the downstream end of the cylindrical part for stabilizing a flame, and the stabilizer is mounted on an inside of the combustor by a plurality of members arranged annularly and secured to the inside of the combustor at their ends, each of the members having a part slidably inserted in an opening of the cylindrical part so as to restrict the stabilizer to move axially while allowing deformation of the stabilizer and another part supporting the upstream end of the cylindrical part so as to restrict radial movement of the stabilizer.

Abstract: A combustor comprises a passage area changing mechanism which relatively moves a flame holder relative to a premixed combustion nozzle in an axial direction so that the area of passage for premixed gas between an injection edge of the premixed combustion nozzle and a peripheral edge of the flame holder can be changed. Stable combustion can be maintained over a wide load range and reduction in NOx can be achieved.

Abstract: A gas turbine apparatus has a gas turbine and a plurality of burners for providing combustion gas to drive the turbine. A flow control means of each burner for fuel or combustion air is adjusted by control means to control each said burner individually in dependence on a predetermined combustion characteristic of the respective burner. Sensed quantities relating to the combustion performance of the burners are input to the control means which adjusts the flow control means of each burner in dependence on the sensed quantities and the predetermined combustion characteristic of the respective burner.

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: First and second premixed burners having annular injection slots are concentrically adjacent and the injection slots are substantially aligned with each other in a longitudinal direction of the burners. A pilot burner is provided substantially in the center of the annular first premixed burner so that the injection slot of the pilot burner is substantially aligned with the injection slot of the first premixed burner in a longitudinal direction of the burner. A flame holder which forms a circulating flow of combusted gas Gh downstream of the flame holder is disposed at the downstream end of a boundary wall between the premixed burners so that the flame holder is co-used by the premixed burners. Flow rate adjusting means for adjusting the flow rate of fuel supplied to the first, second premixed burner and the pilot burner, respectively are provided. The fuel can be substantially uniformly mixed with a combustion gas. Reduction in NOx and stabilization of premixed flame can be achieved.

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 gas turbine includes a cooling air supply device for supplying compressed cooling air to moving blades, and a heat exchanger provided in the cooling air supply device for cooling the compressed cooling air. Compressed air withdrawn at an intermediate-stage portion of a compressor is used as a cooling medium for the heat exchanger. With this construction, the moving blades can be sufficiently cooled without the use of any special cooling medium.

Abstract: A combustor for driving a gas turbine includes a first burning stage and a second burning stage. The combustor further comprises a primary combustion chamber in which air from the associated compressor and fuel are burnt, a pre-mixing chamber in which air from the associated compressor and fuel are pre-mixed, a main combustion chamber in which fuel/air mixture is burnt and forwarded to the gas turbine, an air passage provided in a wall of the main combustion chamber, through which air from the compressor flows to cool the wall thereof, and an intercommunicating air passage for intercommunicating the air passage to the pre-mixing chamber, whereby cooling air for the main combustion chamber wall is used to supplement the air in the pre-mixing chamber.

Abstract: A gas turbine combustor comprising a head combustion chamber and a rear combustion chamber connected to a downstream side of the head combustion chamber, a first stage burner for premixing first stage fuel and air and supplying the resultant fuel and air premixture into the head combustion chamber to effect first stage premix combution, a second stage burner for premixing second stage fuel and air and the resultant fuel and air premixture into the rear combustion chamber to effect premix combustion in addition to the first stage premix combustion, and a device for regulating flow rates of combustion air to be premixed with first and second stage fuel. The combustor is further provided with a pilot burner in the head combustion chamber to form pilot flame and stabilize the first stage premix combustion.

Abstract: A gas turbine combustor has an inner cylinder provided with a multiplicity of louvers for introducing cooling air and a plurality of air ports for introducing combustion air. The portions of the inner cylinder wall at both ends of each louver, where the concentration of stress due to thermal stress is heaviest, is reinforced by build-up welding thereby to prevent cracking at these portions of the cylinder wall. The build-up welding effectively stops the propagation of crack happened to be caused in the inner cylinder wall for any reason. The portions of the inner cylinder wall around the air ports also may be reinforced by build-up welding over the entire peripheries of these air ports. The build-up weld on the periphery of each air port prevents any crack from being propagated to the brim of each air port.

Abstract: A disk chuck mechanism for chucking a disk in a stepped-down portion of a rotary chuck member and releasing the disk by vertically moving a chuck head coupled to an operating shaft is disclosed wherein a ring member having a cut in part is provided for its diameter to be enlarged opposite to the stepped-down portion of the rotary chuck member for chucking the disk and biased in the direction in which its diameter contracts. The chuck head is moved in the axial direction to utilize an inclined side face of the chuck head to enlarge the diameter of the ring member. With this arrangement, it is ensured that the disk is chucked in between the stepped-down portion of the rotary chuck member and the ring member with the one stroke movement of the chuck head.

Abstract: A surface, of an inner sleeve of a combustion apparatus for a gas turbine, which is subjected to a flame radiation heat is coated with a ceramic coating. A coating which is superior in high temperature corrosion resistant characteristics to a metal material forming the inner sleeve is provided on the opposite surface of the inner sleeve. Thus, heat transferred to the inner sleeve by the radiation from the flame is shielded by the ceramic coating. A formation of oxides on the coating of the corrosion resistant metal material formed on the opposite surface of the sleeve is prevented. A heat release through the surface from the metal material forming the inner sleeve is enhanced, whereby a thermal stress generated in the inner sleeve is suppressed to thereby prevent a generation of a cracks.

Abstract: A heat resistant steel of the present invention contains 0.05 to 0.2 wt. % of C, less than 0.5 wt. % of Si, less than 0.6 wt. % of Mn, 8 to 13 wt. % of Cr, 1.5 to 3 wt. % of Mo, 2 to 3 wt. % of Ni, 0.05 to 0.3 wt. % of V, 0.02 to 0.2 wt. % in total of either or both of Nb and Ta, 0.02 to 0.1 wt. % of N and the balance substantially Fe. Since a gas turbine of the present invention is constituted by members, such as discs, blades, shafts and so forth, made of alloys of this kind, the gas turbine has a structure in which it is possible to achieve a high level of creep rupture strength and Charpy impact value.

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 combined gas turbine plant comprises an air compressor, a combustor including a combustion chamber, a gas turbine, a steam turbine, and an exhaust heat recovery device having a denitration device and arranged at a location through which an exhaust gas passage for leading exhaust gas from the gas turbine to the atmosphere extends. An air extraction pipe equipped with a valve is provided for extracting a part of the air from the air compressor to prevent surging of the air compressor during starting of the plant, and another air extraction pipe equipped with a valve is provided for extracting a part of the air from an air passage extending from the compressor to the combustion chamber to improve stability of a flame and combustibility in the combustion chamber during the plant starting. The extraction pipes extend to and hence lead the extracted air into a portion of the exhaust gas passage located downstream of the denitration device.

Abstract: A gas turbine combustor for reducing a production of NOx. The combustor includes a head combustion chamber and a rear combustion chamber which is larger in diameter than the head combustion chamber. The head combustion chamber is provided with an axially extending hollow frustoconical tubular member to form an annular combustion space therein, air holes for axially jetting air into the annular combustion chamber, air holes formed on a peripheral wall for injecting air and a plurality of fuel nozzles projected into the annular combustion space for injecting fuel into vortex formed by the air jet and the injected air flow whereby the flame is stabilized and lean combustion can be effected. The rear combustion chamber has a fuel and air supply means on the upstream side which includes air inlets formed by whirling vanes and fuel nozzles disposed in the air inlets so that fuel and air are mixed well.

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: A heat resistant steel of the present invention contains 0.05 to 0.2 wt. % of C, less than 0.5 wt. % of Si, less than 0.6 wt. % of Mn, 8 to 13 wt. % of Cr, 1.5 to 3 wt. % of Mo, 2 to 3 wt. % of Ni, 0.05 to 0.3 wt. % of V, 0.02 to 0.2 wt. % in total of either or both of Nb and Ta, 0.02 to 0.1 wt. % of N and the balance substantially Fe. Since a gas turbine of the present invention is constituted by members, such as discs, blades, shafts and so forth, made of alloys of this kind, the gas turbine has a structure in which it is possible to achieve a high level of creep rupture strength and Charpy impact value.