Hitachi, Ltd.

Hitachi Kizai Kogyo Co. Ltd.

Yoshiaki Yamazaki

Kiyoshi Namura

Masakazu Takasumi

Eiji Saito

Yoshio Shikano

Michio Kuroda

Shigeki Senoo

Takeshi Onoda

Kazuo Ikeuchi

Fumio Kato

Yutaka Yamashita

Yoshiharu Nakayama

Masumi Katayose

Kiyoshi Segawa

Shigemichi Inoue

Takeshi Sato

Yasuaki Akatsu

Satoshi Ninomiya

Tetsu Imai

Akira Ishida

Akio Sohma

Tutomu Iwasaki

Daizo Morimoto

The pressure distribution curve of the blade suction-side surface excluding the leading edge portion and the trailing edge portion drops in two stages in the area from the leading edge to the minimum pressure point.

Turbine blade and turbine

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 &#xb1;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.

Turbine bucket

A turbine moving blade operated by a working fluid and having a blade profile formed so that a pressure distribution curve defined by a pressure on a blade surface of a suction side of the moving blade drops in two stages in an area from a leading edge to a minimum pressure point.

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 &plusmn;0.3 mm from respective points defining blade section configurations.

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.

Steam turbine

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.

An apparatus of stationary blade for an axial flow turbine includes a diverging flow channel for flowing an elastic fluid and stationary blades which are fixed at the diverging flow channel and are curved in perpendicular direction to the flow direction of the elastic fluid. The stationary blades form the same tangential lean angles at the leading edge and the trailing edge of the stationary blade corresponding to the flow direction of the elastic fluid, and an axial flow turbine has the apparatus of stationary blades thereof. The stationary blade distributes the fluid in the flow channel uniformly and, consequently, improves the efficiency of the flow.

Apparatus of stationary blade for axial flow turbine, and axial flow

A turbomachine rotor arrangement is provided having a rotor wheel and blades thereon with a tie pin for interconnecting adjacent blades. A plurality of blades respectively define tie holes wherein the tie holes of adjacent blades are disposed with the radial heights of said holes being different and with the tie pin disposed in the tie holes so as to be acted upon by respective different amplitudes of vibration than said adjacent blades during rotation.

Turbine rotor construction

A plurality of turbine buckets annularly arranged around a rotor are each provided with a ledge disposed at right angles to the outer surface of each bucket. Each ledge includes a leading end portion and a trailing end portion each formed therein with a vertical hole, leading and trailing end portions of the ledge of each turbine bucket extending in opposite directions on both sides of the bucket. There are provided cover pieces each interposed between ends of the adjacent two turbine buckets and formed on the upper surface with a plurality or cylindrical projections adapted to be loosely received in the vertical holes formed in the ledges of the adjacent two turbine buckets. Contact surfaces adapted to be brought into contact with the undersides of the ledges are formed on the upper surface of each cover piece and interposed between the cylindrical projections, and an upper end portion of at least one of the cylindrical projections is machined to provide an enlarged diameter projection portion so as to preclude dislodging of the projection from the hole whereby the cover piece can positively connect the adjacent two buckets together.

Growing community of inventors

Hitachi, Japan

Yoshiaki Yamazaki