Abstract: A turbine moving blade has a blade portion extending from the basal portion to the tip of the moving blade. The blade root portion is formed at the basal portion of the blade portion and engaged with a corresponding disk groove of a turbine rotor on a one-by-one basis, and the integral cover is formed at the tip of the blade portion integrally with the blade portion. The integral cover includes at least a pair of pressure and suction sloped surfaces inclined relative to the direction of the rotational axis of a turbine so as to restrain the elastic restoring force of the moving blade torsionally deformed at the time of installation of the moving blade by bringing the integral covers of mutually adjacent blades into contact.

Abstract: A turbine moving blade has a blade portion extending from the basal portion to the tip of the moving blade. The blade root portion is formed at the basal portion of the blade portion and engaged with a corresponding disk groove of a turbine rotor on a one-by-one basis, and the integral cover is formed at the tip of the blade portion integrally with the blade portion. The integral cover includes at least a pair of pressure and suction sloped surfaces inclined relative to the direction of the rotational axis of a turbine so as to restrain the elastic restoring force of the moving blade torsionally deformed at the time of installation of the moving blade by bringing the integral covers of mutually adjacent blades into contact.

Abstract: The present invention relates to a turbine bucket to be provided at the low pressure last stage of a steam turbine and an object of the present invention is to provide a turbine bucket in which the adjacent blades are connected without using a connecting member at a blade intermediate portion. In order to achieve the object of the present invention, a turbine bucket of the present invention is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, and when assuming two axial directions in a blade section of the bucket on horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at predetermined heights from the blade root portion of the turbine bucket are formed in a range of ±0.3 mm from respective points defining blade section configurations as shown respectively in chart 1, chart 4, chart 7, chart 10, chart 13, chart 16 and chart 18.

Abstract: The present invention relates to a turbine bucket to be provided at the low pressure last stage of a steam turbine and an object of the present invention is to provide a turbine bucket in which the adjacent blades are connected without using a connecting member at a blade intermediate portion. In order to achieve the object of the present invention, a turbine bucket of the present invention is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, and when assuming two axial directions in a blade section of the bucket on horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at predetermined heights from the blade root portion of the turbine bucket are formed in a range of ±0.3 mm from respective points defining blade section configurations as shown respectively in chart 1, chart 4, chart 7, chart 10, chart 13, chart 16 and chart 18.

Abstract: The present invention is a turbine bucket for at the low pressure last stage of a steam turbine and in which the adjacent blades are connected without using a connecting member at a blade intermediate portion. A turbine bucket of the present invention is formed that the blade sectional configuration is twisted from a blade root portion to a blade tip side, and when assuming two axial directions in a blade section of the bucket on horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at predetermined heights from the blade root portion of the turbine bucket are formed in a range of ±0.3 mm from respective points defining blade section configurations.

Abstract: The moving blades of a rotor included in a steam turbine are formed so that the width of a gap between opposite end surfaces of first connecting members of adjacent blades along the direction of rotation of the rotor and the width of a gap between opposite end surfaces of second connecting members of the adjacent blades along the direction of rotation of the rotor are determined so as to make the second connecting members start coming into contact with each other at a rotating speed of the rotor higher than a rotating speed at which the first connecting members of the adjacent blades start to come into contact with each other.

Abstract: A steam turbine is intended for use in a thermal or nuclear power plant. The moving blades of a rotor included in a steam turbine vibrate as the rotor rotates, inducing an excessive stress in joints of connecting members for connecting the adjacent moving blades and blade portions of the moving blades and damaging the joints. It is a task of the invention to prevent moving blades from being damaged due to vibration.

Abstract: A steam turbine for use in a thermal or nuclear power plant includes moving blades of a rotor which vibrate as the rotor rotates, inducing an excessive stress in joints of connecting members for connecting the adjacent moving blades and blade portions of the moving blades and damaging the joints. The moving blades are formed so that a width of a gap between opposite end surfaces of first connecting members of adjacent blades along the direction of rotation of the rotor and a width of a gap between opposite end surfaces of second connecting members of the adjacent blades along a direction of rotation of the rotor are determined so as to make the second connecting members start coming into contact with each other at a rotating speed of the rotor higher than a rotating speed at which the first connecting members of the adjacent blades start come into contact with each other.

Abstract: A steam turbine is provided with moving blades which are affected less by erosion and fretting wear due to water and have a high reliability in strength. The moving blades are twisted moving blades, each provided with a blade portion and a shroud portion formed at its tip and a contact surface between shroud portions connecting adjacent moving blades whereby an extension plane of the contact surface toward the blade back side does not intersect with the blade tip of the blade back side shroud portion.

Abstract: The total number (M) of plural blades of a blade apparatus is selected so as not to be a prime number and not to be a power multiplier of a prime number. Plural blades are divided into at least a first blade group in which one blade group has the blades of a first integer number (N.sub.1) and a second blade group in which one blade group has blades of a second integer number (N.sub.2). Each of the first integer number (N.sub.1) and the second integer number (N.sub.2) have no common divisor except 1. The total number (M) of plural blades is the product of the first integer number (N.sub.1) and the second integer number (N.sub.2). The blades of the first integer number (N.sub.1) blade group are connected by a first stage connecting member and the blades of the second integer number (N.sub.2) blade group are connected by a second stage connecting member.

Abstract: A method and apparatus for monitoring cracks of a rotatable body by detecting cracks by measuring accoustic emission signals and evaluating the depth of cracks from the result of the comparison of assumed vibrations of the rotatable body and its measured vibrations. By this method and apparatus not only the beginning of cracking of the rotatable body, but also the progress of cracking on an online basis can be detected and monitored.

Abstract: A vibration diagnosis method and apparatus for rotary machines adapted for measuring the vibration of rotor shaft of a rotary machine, extracting the vibration component synchronous with the revolution of the rotor shaft from the measured vibration data, comparing the amplitude of the extracted vibration component with the amplitude of the overall vibration, analyzing the causes of the synchronous vibration component when the result of the comparison meets a predetermined reference, judging, in accordance with the result of the analysis, whether the vibration due to mass unbalance is attributable to an abrupt generation of mass unbalance or to a thermal bow of the rotor shaft, and displaying the result of the judgment. The analysis of the vibration component is made in real time or making use of data stored in the past.

Abstract: A vibration diagnosis method for a rotary machine is disclosed. The presence or absence of a self-excited vibration is determined by checking if a rotating speed is in a rotating speed range which allows the occurrence of the self-excited vibration, if an amplitude of a frequency component corresponding to a first order critical speed is larger than a predetermined level, and if phases at characteristic points of vibration signals change among cycles.

Abstract: A method and apparatus for diagnosing a vibration in a rotor of the rotary machine including detecting the number of rotations and the vibration in the rotor when the rotor is rotating, extracting a vibration component synchronized with the number of rotations, determining whether the vibration component is normal or abnormal, calculating an abnormal vibration component through a vector operation by using the detected vibration component and a previously determined rotor vibration component in a normal state of the rotor, when the detected vibration component is judged to be abnormal, normalizing a vibration pattern of the abnormal vibration component, and determining an unbalance originating position in the rotor, which generates the abnormal vibration, by using a comparison of the normalized abnormal vibration pattern with a normalized vibration pattern of a previously determined unbalanced vibration.

Abstract: A balancing method for use in a multiple-span rotor shaft system for a prime mover, such as a large-capacity, large-sized steam turbine and generator. A balancing influence coefficient representing the relationship between a unit weight and the resultant vibration, when the aforesaid unit weight is attached to a given balance-correcting plane of a multiple span rotor, is first determined, and then a balance-correcting plane, to which is to be attached a balancing weight, is selected, then a balancing weight is determined so as to minimize the value of the residual vibration amplitude, by using the method of least squares, which values are dependent on the value of the vibration amplitude, influence coefficients and balancing weights. Thus, a weight corresponding to the aforesaid balancing weight is attached to the aforesaid balance-correcting plane to reduce vibrations in a shaft.