Hitachi, Ltd.

Mitsubishi Hitachi Power Systems, Ltd.

Tateki Nakamura

Takeshi Kudo

Kunio Asai

Kenichi Hattori

Kenichi Tomita

Makoto Hemmi

Yukihiro Yamamoto

Kengo Iwashige

Tomoaki Yamashita

Takayasu Tanaka

Yasunori Shigenaga

Kenichi Tohrisawa

Fumiyuki Suzuki

Shigeki Senoo

Masahiko Arai

Hirotsugu Kawanaka

Eiji Saito

Yutaka Yamashita

Naoaki Shibashita

Koji Ogata

Eiji Kumakura

A hydro dynamic bearing device comprising an upper half of a main bearing and a lower half of the main bearing, wherein the upper half of the main bearing is lined with a low-strength metal such as a Babbitt metal, wherein a circumferential groove is formed in the lower half of the main bearing, and wherein the low-strength metal of the upper half of the main bearing, which is formed at a region opposed to a downstream side of the circumferential groove formed in the lower half of the main bearing, is partially removed to cause a high-strength bearing base metal to be partially exposed.

Hydro dynamic bearing device

A turbine bucket for a steam turbine low-pressure final stage has an exhaust area exceeding 9.6 mand 13.8 min steam-turbine final-stage buckets for a rated speed 3600 rpm and 300 rpm machines, respectively. The turbine bucket is made of martensite steel. A blade portion of the turbine bucket has a suction surfaceand a pressure surfacewhich are each formed, at a turbine blade root, of three areas consisting of a steam inlet side areawith curvature, a steam outlet side areawith curvature and an approximately straightly formed area located between the two areas.

Turbine bucket

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.

Long steam turbine rotor blade having particular cover

A steam turbine test facilityincludes a test steam turbinewhich simulates the behavior of a real steam turbinesincluded in the steam turbine plant, and a motor-generatorconnected to the test steam turbine. A control unitincluded in the motor-generatorcontrols the motor-generatorto change the rotational speed of the test steam turbinebased on an arbitrarily set speed change pattern. The speed change pattern is set such that the test steam turbinein the load disconnection state simulates a time-profile of the rotational speed of the steam turbineswith the load disconnected.

Steam turbine test facility, low-load test method, and load dump test method

A casing is formed from an alloy which contains, by mass, 0.08-0.20% C, 0.05-0.45% Si, 0.10-0.30% Mn, 0.80-1.40% Ni, 1.00-1.40% Cr, 1.20-1.60% Mo, 0.10-0.30% V, 0.06-0.10% Ti, 0.0005-0.0010% B, not more than 0.01% P, not more than 0.01% S, and not more than 0.005% Al, the balance being Fe and unavoidable impurity elements. The casing has excellent high-temperature strength, high toughness and excellent weldability, and is applicable to casings used in high-temperature high-pressure steam environments.

Turbine casing

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&#x2267;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&#x2212;1)th hook from the outermost circumferential rotor hook, and a convex portion of the (n&#x2212;2)th hook.

Turbine rotor and turbine blade

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&#x3e;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&#x3e;Wbi).

Steam turbine rotor, inverted fir-tree turbine blade, low pressure steam turbine with those rotors and blades, and steam turbine power plant with those turbines

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Hitachi, Japan

Tateki Nakamura