Abstract: A steam turbine includes a flow guide placed about a rotor shaft and forming a side wall of a diffuser. The flow guide is formed in such a substantially truncated conical shape that a first portion having a semi-circular-arc cross section and a second portion having a semi-circular-arc cross section and exhibiting less thermal deformation than the first portion are combined together. A coupling portion of the first portion with the second portion has a first protrusion protruding, in the circumferential direction thereof, more on a rotor shaft side than on a steam flow path side of the diffuser. A coupling portion of the second portion with the first portion has a second protrusion protruding, in the circumferential direction thereof, more on the steam flow path side of the diffuser than on the rotor shaft side and overlapping with the first protrusion in the radial direction of the flow guide.

Abstract: An object of the present invention is to provide a turbine external compartment, a frame for a turbine external compartment, and a method of constructing a frame for a turbine external compartment that can improve a flow of steam inside of the compartment and can enhance the rigidity of the compartment using a simple structure. A turbine external compartment according to the present invention is placed in a frame having a steel-plate reinforced concrete structure obtained by filling a space between a plurality of steel plates with concrete. The turbine external compartment includes a lower half part having a side plate part or an end plate part made of the steel plates that constitute the frame.

Abstract: A stack ring is formed by an outer ring and an inner ring and is inserted in an annular gap formed between an inlet sleeve and an inner casing. The outer periphery of the outer ring and the inner periphery of the inner ring each have a land part having a flat face and taper faces formed on upper and lower sides of the land part. A ratio of L1 to L0 is 0.3 to 0.7 where L1 is a length of the land part and L0 is a total length in the up-down direction. A ratio of S to S0 is not less than 0.95 where S is an area of the cross sectional shape of the outer ring or the inner ring and S0 is an area of a virtual rectangle BCDE and the taper faces have an inclined angle of 1° to 10°.

Abstract: A steam turbine includes a flow guide placed about a rotor shaft and forming a side wall of a diffuser. The flow guide is formed in such a substantially truncated conical shape that a first portion having a semi-circular-arc cross section and a second portion having a semi-circular-arc cross section and exhibiting less thermal deformation than the first portion are combined together. A coupling portion of the first portion with the second portion has a first protrusion protruding, in the circumferential direction thereof, more on a rotor shaft side than on a steam flow path side of the diffuser. A coupling portion of the second portion with the first portion has a second protrusion protruding, in the circumferential direction thereof, more on the steam flow path side of the diffuser than on the rotor shaft side and overlapping with the first protrusion in the radial direction of the flow guide.

Abstract: A steam turbine casing position adjusting apparatus capable of employing a compact low-resolution actuator is provided. A steam turbine casing position adjusting apparatus 40 includes turbine casings 21 and 37, a rotor 23, and actuators 14 and 15 that move the turbine casings 21 and 37 in the axial direction. The actuators 14 and 15 are disposed radially outside outer peripheries forming the turbine casings 21 and 37 .

Abstract: A steam turbine has an outer casing that is divided into an upper casing and a lower casing (a lower block) on a horizontal plane through which a rotor passes. The upper casing is divided into a middle block having a through hole and an upper block having a top panel, that is, into a portion including at least a part of the through hole through which the rotor penetrates. With this configuration, machining of a bellows fitting unit provided in an end-plate cone portion can be performed in existing facilities such as a factory, in a state that the lower block and the middle block are assembled without assembling the upper block.

Abstract: A stack ring is formed by an outer ring and an inner ring and is inserted in an annular gap formed between an inlet sleeve and an inner casing. The outer periphery of the outer ring and the inner periphery of the inner ring each have a land part having a flat face and taper faces formed on upper and lower sides of the land part. A ratio of L1 to L0 is 0.3 to 0.7 where L1 is a length of the land part and L0 is a total length in the up-down direction. A ratio of S to S0 is not less than 0.95 where S is an area of the cross sectional shape of the outer ring or the inner ring and S0 is an area of a virtual rectangle BCDE and the taper faces have an inclined angle of 1° to 10°.

Abstract: A sealing mechanism includes a pair of space forming rings which face each other and are configured for surrounding a shaft body, an outer bellows-joint having one end connected to an outer periphery of one of the space forming rings and another end connected to an outer periphery of the other of the space forming rings, and an inner bellows-joint having one end connected to an inner periphery of one of the space forming rings and another end connected to an inner periphery of the other of the space forming rings. Each of the inner bellows-joint and the outer bellows-joint is a corrugated plate. The space forming rings space the inner bellows-joint and the outer bellows-joint apart from each other such that the inner bellows-joint and the outer bellows-joint do not come in contact with each other.

Abstract: A first seal member includes a double-structure bellows in corrugated form, and vibration control device provided on the outside of the bellows such as to cover part of the bellows. A flat portion that is not in corrugated form is provided in part of the bellows. The vibration control device is provided in circumferential direction on an outer surface of the flat portion, and made up of a ring-shaped rib having a plurality of holes in a circumferential direction and weights inserted in the holes provided in a wall of rib. Natural frequency is adjusted by adjusting the number of weights, thereby preventing resonance between the natural frequency of the first seal member and the rotational frequency of rotor from occurring.

Abstract: An object of the present invention is to provide a turbine external compartment, a frame for a turbine external compartment, and a method of constructing a frame for a turbine external compartment that can improve a flow of steam inside of the compartment and can enhance the rigidity of the compartment using a simple structure. A turbine external compartment according to the present invention is placed in a frame having a steel-plate reinforced concrete structure obtained by filling a space between a plurality of steel plates with concrete. The turbine external compartment includes a lower half part having a side plate part or an end plate part made of the steel plates that constitute the frame.

Abstract: A steam turbine casing position adjusting apparatus capable of employing a compact low-resolution actuator is provided. A steam turbine casing position adjusting apparatus 40 includes turbine casings 21 and 37, a rotor 23, and actuators 14 and 15 that move the turbine casings 21 and 37 in the axial direction. The actuators 14 and 15 are disposed radially outside outer peripheries forming the turbine casings 21 and 37.

Abstract: Providing a sealing mechanism provided with bellows-joints, the sealing mechanism being manufactured without surplus time and labor; thereby, the natural frequencies regarding the sealing mechanism surrounding a to-be-sealed shaft body are easily handled. Around a rotor shaft 26 of a steam turbine 10, between an outer turbine casing 12 and a gland 32, a sealing mechanism 40A is provided; the sealing mechanism is provided with an outer bellows-joint 46 and an inner bellows-joint 48, both the joints being arranged without mutual contact; the left and right ends of the outer bellows-joint 46 are gas-tightly connected to the outermost end periphery of the end flange 42 and the end flange 44, respectively; the left and right ends of the inner bellows-joint 48 are gas-tightly connected to the innermost end periphery of the end flange 42 and the end flange 44, respectively. Positioning both the bellows-joints can be easily performed.

Abstract: In a steam turbine according to a first embodiment, an outer casing 11 is divided into an upper casing 31 and a lower casing (a lower block) 32 on a horizontal plane through which a rotor passes, and the upper casing 31 is divided into a middle block 33 having a through hole 20 and an upper block 34 having a top panel 31a, that is, into a portion including at least a part of the through hole 20 through which the rotor penetrates and other parts. With this configuration, machining of a bellows fitting unit provided in an end-plate cone portion 21A can be performed in existing facilities such as a factory, in a state that the lower block 32 and the middle block 33 are assembled without assembling the upper block 34.

Abstract: A first seal member 21A according to a first embodiment of the present invention includes a double-structure bellows 22 in corrugated form, and vibration control means provided on the outside of the bellows 22 such as to cover part of the bellows 22. A flat portion 23 that is not in corrugated form is provided in part of the bellows 22. The vibration control means is provided in a circumferential direction on an outer surface of the flat portion 23, and made up of a ring-shaped rib 25 having a plurality of holes in a circumferential direction and weights 26 inserted in the holes provided in an outer wall of the rib 25. Natural frequency is adjusted by adjusting the number of weights 26, thereby preventing resonance between the natural frequency of the first seal member 21A and the rotational frequency of a rotor from occurring.