Abstract: In a stress corrosion cracking evaluation method for a steam turbine, a sample having a high sensitivity is housed in a sample box of the steam turbine, and a sample breakage time is acquired. Then, based on the sample breakage time, a breakage time of the steam turbine is estimated.

Abstract: A steam turbine according to the present invention comprises: a shaft which rotates about the rotation axis thereof; a plurality of moving blades which extend in the radial direction from the outer peripheral surface of the shaft and which are arranged along the circumferential direction; a casing main body which covers the shaft and the moving blades from the outer peripheral side; a plurality of stationary blades which are arranged on the inner circumferential surface of the casing main body; and a substance supply unit which supplies, to the surfaces of the moving blades and/or the surfaces of the stationary blades, a film forming substance that is hydrophobic, wherein the substance supply unit has a storage unit, a supply passage which is formed inside the casing and through which the film forming substance flows, and discharge units which are formed inside the moving blades and/or the stationary blades and which guide the film forming substance to the surfaces.

Abstract: This high-frequency hardening apparatus is provided with: an induction heating coil which has a U-shaped part that sandwiches a turbine blade, a pair of linear parts, and a connection part connecting the U-shaped part and the linear parts; a temperature detection unit which detects, in a non-contact manner, temperature around the induction heating coil; a moving mechanism which relatively moves the turbine blade and the induction heating coil in the direction of blade height; an electrical current supply unit which supplies a high-frequency electrical current to the induction heating coil; and a control device which has an electrical current control unit that, on the basis of a detection value provided by the temperature detection unit, controls the magnitude of the high-frequency electrical current supplied from the electrical current supply unit such that the detection value will not exceed a predetermined temperature.

Abstract: A water quality monitoring system is disclosed including a sampling pipe that acquires steam that passes a bleed pipe that bleeds steam from a low pressure turbine to which steam of low pressure is supplied from among steam turbines, a steam inlet tank into which the steam acquired by the sampling pipe flows, a water quality measurement apparatus that measures the water quality of condensed water condensed from the steam flowed in the steam inlet tank, and a water quality diagnosis apparatus that diagnoses the water quality of the condensed water using a result of the measurement of the water quality measurement apparatus. The steam inlet tank is installed at a location higher than that of the water quality measurement apparatus such that the water quality measurement apparatus measures the water quality of the condensed water boosted to the atmospheric pressure utilizing the head difference.

Abstract: A rubbing detection device for a rotary machine includes an AE sensor configured to acquire an AE signal of a rotary machine, an index calculation unit configured to calculate a rubbing detecting index for determining the presence or absence of rubbing based on information relating to a phase of the AE signal, and a determination unit configured to determine the presence or absence of rubbing based on the rubbing detecting index.

Abstract: A water quality monitoring system is disclosed including a sampling pipe that acquires steam that passes a bleed pipe that bleeds steam from a low pressure turbine to which steam of low pressure is supplied from among steam turbines, a steam inlet tank into which the steam acquired by the sampling pipe flows, a water quality measurement apparatus that measures the water quality of condensed water condensed from the steam flowed in the steam inlet tank, and a water quality diagnosis apparatus that diagnoses the water quality of the condensed water using a result of the measurement of the water quality measurement apparatus. The steam inlet tank is installed at a location higher than that of the water quality measurement apparatus such that the water quality measurement apparatus measures the water quality of the condensed water boosted to the atmospheric pressure utilizing the head difference.

Abstract: It is an objective of the invention to provide a steam turbine rotor that is capable of both reducing SCC susceptibility and improving LCF life thereof. There is provided a steam turbine rotor, comprising a rotor disk in a low pressure final stage L-0, and another rotor disk in a plurality of stages including a stage L-1 positioned closer to a high pressure side than the low pressure final stage L-0, the rotor disk in the low pressure final stage L-0 and the rotor disk in a plurality of stages including the stage L-1 being joined by welding, wherein a material of both the rotor disk in the low pressure final stage L-0 and the rotor disk in a plurality of stages including the stage L-1 is a 12Cr steel and has a tensile strength of 900 to 1200 MPa.

Abstract: A blade avoids fretting damage while reducing stress occurring at the neck portion caused by a stress relief groove. The blade is disposed on an outer periphery of a rotor, and includes a blade portion, a dovetail portion for holding the blade on the rotor, a platform portion that connects the dovetail portion and the blade portion, and a stress relief groove that connects a side surface of the platform portion and a blade load bearing surface of the dovetail portion. The dovetail portion has a width that increases toward its bottom side within a range from a connection point between the side surface of the platform portion and the stress relief groove to a connection point between the dovetail portion and the stress relief groove.

Abstract: A steam turbine having a fork-type joint structure is provided that secures sufficient strength for endurance of stress corrosion cracking, low-cycle fatigue, and high-cycle fatigue, and extends an operating life while making it possible to endure long-term operation. The turbine includes a rotor having a plurality of rotor forks rowed in an axial direction; a turbine blade having blade forks arranged in the axial direction of the rotor, the blade forks engaged with the rotor forks; a plurality of pin holes whose positions are different from each other in the radial direction of the rotor; and a plurality of fork pins inserted into the plurality of pin holes in the axial direction of the rotor. A clearance exists between an inner diameter of the pin hole of the blade fork and a diameter of the fork pin, the clearance varying depending on positions in the axial direction of the turbine.

Abstract: It is an objective of the invention to provide a steam turbine rotor that is capable of both reducing SCC susceptibility and improving LCF life thereof. There is provided a steam turbine rotor, comprising a rotor disk in a low pressure final stage L-0, and another rotor disk in a plurality of stages including a stage L-1 positioned closer to a high pressure side than the low pressure final stage L-0, the rotor disk in the low pressure final stage L-0 and the rotor disk in a plurality of stages including the stage L-1 being joined by welding, wherein a material of both the rotor disk in the low pressure final stage L-0 and the rotor disk in a plurality of stages including the stage L-1 is a 12Cr steel and has a tensile strength of 900 to 1200 MPa.

Abstract: A turbine rotor blade which is enhanced in erosion resistance and reduced in stress corrosion cracking sensitivity is provided. When a blade tip end of the turbine rotor blade is hardened by heat treatment, hardness at an outer circumferential side in a radial direction is made higher than hardness at an inner circumferential side, and thereby, enhancement in erosion resistance and reduction in stress corrosion cracking sensitivity are made compatible with each other all over in a blade length direction.

Abstract: Disclosed herein is a blade that avoids fretting damage, while reducing stress occurring at the neck portion as caused by the stress relief groove. The blade disposed on an outer periphery of a rotor is provided. The blade includes: a blade portion; a dovetail portion for holding the blade on the rotor; a platform portion that connects the dovetail portion and the blade portion; and a stress relief groove that connects a side surface of the platform portion and a blade load bearing surface of the dovetail portion, wherein the dovetail portion has a width that increases toward a bottom side thereof within a range from a connection point between the side surface of the platform portion and the stress relief groove to a connection point between the dovetail portion and the stress relief groove.

Abstract: A steam turbine rotor blade has a profile and a cover integrally formed on and at an end of the profile, the leading edge of the cover formed on the profile and the trailing edge of a cover formed on an adjacent preceding profile being in contact and connected with each other by the torsional return force produced during rotation. The cover formed on the profile is provided with a radially-formed stepped portion at the trailing edge, the stepped portion having a height large than the thickness of the cover.

Abstract: A steam turbine having a fork-type joint structure is provided that secures sufficient strength for endurance of stress corrosion cracking, low-cycle fatigue, and high-cycle fatigue, and extends an operating life while making it possible to endure long-term operation. The turbine includes a rotor having a plurality of rotor forks rowed in an axial direction; a turbine blade having blade forks arranged in the axial direction of the rotor, the blade forks engaged with the rotor forks; a plurality of pin holes whose positions are different from each other in the radial direction of the rotor; and a plurality of fork pins inserted into the plurality of pin holes in the axial direction of the rotor. A clearance exists between an inner diameter of the pin hole of the blade fork and a diameter of the fork pin, the clearance varying depending on positions in the axial direction of the turbine.

Abstract: It is an objective of the present invention to provide an effective use of the friction stir processing (FSP) technology for Ti-alloy turbine blades with a long radial length, and provide a Ti-alloy turbine blade having both high erosion resistance and high long term reliability. There is provided a turbine blade made of an ?-? titanium alloy having an average Vickers hardness of 320 Hv or less, the turbine blade having a leading edge, in which: the turbine blade includes, at the leading edge thereof, a first hardened surface region having a thickness of from 0.5 to 3.0 mm and having an average Vickers hardness of 340 Hv or more; and the first hardened surface region is formed by friction stir processing a surface region of the leading edge of the turbine blade.

Abstract: A turbine rotor blade which is enhanced in erosion resistance and reduced in stress corrosion cracking sensitivity is provided. When a blade tip end of the turbine rotor blade is hardened by heat treatment, hardness at an outer circumferential side in a radial direction is made higher than hardness at an inner circumferential side, and thereby, enhancement in erosion resistance and reduction in stress corrosion cracking sensitivity are made compatible with each other all over in a blade length direction.

Abstract: A turbine rotor improved in machinability, appropriately balanced in stress, and having rotor hooks and rotor necks constructed to form an attachment structure with respect to an inverted fir tree blade root that has blade hooks and blade necks. The turbine rotor has rotor hooks and rotor necks constructed to form an attachment structure with respect to an inverted fir tree blade root that has blade hooks and blade necks with an “n” number of hooks, where n?3. In this structure, a convex portion of the innermost circumferential rotor hook is formed to be concave in a circumferential direction, with respect to a tangential line that connects a convex portion of the (n?1)th hook from the outermost circumferential rotor hook, and a convex portion of the (n?2)th hook.

Abstract: In a turbine rotor, a rotor radial-direction hook length (Hri) of an i-th rotor hook counting from the outermost circumference of the rotor and a blade radial-direction hook length (Hbi) of an i-th blade hook counting from the outermost circumference of the blade are set to satisfy the relationship of (Hri>Hbi). In the turbine blade, a rotor circumference-direction neck width (Wri) of an i-th rotor neck counting from the outermost circumference of the rotor and a blade circumference-direction neck width (Wbi) of an i-th blade neck counting from the innermost circumference of the blade are set to satisfy the relationship of (Wri>Wbi).

Abstract: A subject of the present invention is to prevent the reduction of rigidity caused by the increased length of a steam turbine rotor blade and the degradation of vibration characteristics. A steam turbine rotor blade according to the present invention comprises a profile and a cover integrally formed on and at an end of the profile, the leading edge of the cover formed on the profile and the trailing edge of a cover formed on an adjacent preceding profile being in contact and connected with each other by the torsional return force produced during rotation, and wherein the cover formed on the profile is provided with a radially-formed stepped portion at the trailing edge, the stepped portion having a height large than the thickness of the cover.

Abstract: The present invention provides a turbine rotor improved in machinability, appropriately balanced in stress, and having rotor hooks and rotor necks constructed to form an attachment structure with respect to an inverted fir tree blade root that has blade hooks and blade necks. The turbine rotor of the present invention has rotor hooks and rotor necks constructed to form an attachment structure with respect to an inverted fir tree blade root that has blade hooks and blade necks with an “n” number of hooks, where n?3. In this structure, a convex portion of the innermost circumferential rotor hook is formed to be concave in a circumferential direction, with respect to a tangential line that connects a convex portion of the (n?1)th hook from the outermost circumferential rotor hook, and a convex portion of the (n?2)th neck.