Hitachi, Ltd.

Hitachi Plant Technologies, Ltd.

Hitachi Industries Co., Ltd.

Haruo Miura

Hideo Nishida

Naohiko Takahashi

Kazuki Takahashi

Hiromi Kobayashi

Yasuo Fukushima

Kazuo Takeda

Haruo Koharagi

Miyoshi Takahashi

Seiji Tsuru

Tsukasa Taniguchi

Yoshiaki Abe

Minoru Taniyama

Takashi Eino

Shigeru Arai

Tsunehiro Endou

Youichirou Fukai

Satoshi Kikuchi

Sadashi Tanaka

Kiyoshi Sakamoto

Kouki Yamamoto

Tomohiro Naruse

Takeo Takagi

Kazutoshi Yanagihara

Hiroto Yoshikai

Mitsuhiro Narita

Akira Endo

Hiroshi Fujii

Tsunehiro Endo

Koji Kotani

Manabu Yagi

Takashi Nagaoka

Toshio Kaneko

Kazuyuki Yamaguchi

Shinichi Wakui

Masaharu Senoh

Tetsuya Kuwano

Taiji Hashimoto

Tadashi Kaneki

Toshio Hattori

Yohei Magara

Souji Sakata

Hiroshi Ohmachi

Tomoyuki Ishikawa

Minoru Yoshihara

Shinichiro Kurita

Akinori Akanuma

Sooji Sakata

Shigenobu Ohashi

Yasumasa Todoroki

A performance prediction device includes: an actual measured data obtaining unit that obtains actual measured data of a compressor; a test gas physical property correction formula database in which test gas physical property correction formulae are stored; a test parameter calculation unit that calculates test parameters of the compressor; and a test parameter correction unit that selects at least one of the test gas physical property correction formulae from the test gas physical property correction formula database based on types and a mix ratio of gases included in a test gas to be used in the prediction and corrects the test parameters by using the selected test gas physical property correction formula.

Performance prediction device and performance prediction method for compressor

In a centrifugal compressor, for the purpose of preventing the positions of a diaphragm and a head flange in a radial direction from moving with respect to a casing, preventing the unstable vibration of the rotor and enabling an efficient and stable operation even on high-pressure conditions, there is provided a barrel-shaped centrifugal compressor including a casing, a diaphragm located in the casing to define a flow channel, and a head flange attached to the end of the casing by a shear key, wherein in the inner peripheral surface of the casing and the outer peripheral surface of abutment portions of the diaphragm and the head flange in which they are abutted on the inner peripheral surface of the casing, sliding key grooves which are vertical to the surfaces are provided at least two portions in a peripheral direction, and sliding keys are provided in the key grooves.

Barrel-shaped centrifugal compressor

A vibration characteristic measuring apparatus includes a magnetic bearing that generates magnetic force on the rotating body of a multi-stage centrifugal compressor, a displacement sensor that measures the vibration amplitude of the rotating body, a current amplifier that supplies a current to the magnetic bearing, and an excitation controller which outputs an excitation control signal for applying vibration to the rotating body and which measures the response characteristics of the vibration of the rotating body to the excitation control signal. The excitation controller outputs a rotating body control signal obtained by adding a vibration eliminating signal for eliminating unbalance vibration of the rotating body to the excitation control signal when measuring the response characteristics, and the current amplifier supplies a current that generates magnetic force in accordance with the rotating body control signal to the magnetic bearing.

Apparatus and method for measuring vibration characteristics

Size reduction of a barrel-type casing using a shear key is aimed for while ensuring a necessary area of a head cover end surface. A shoulder is formed on the axially outer side of the outer circumferential surface of a head cover. The inner surface of a casing is provided with a circumferentially extending groove. Shear key structure includes a first shear key member disposed in the shoulder and the groove, such that at least a portion of its outer circumferential surface is in contact with the inner circumferential surface of the groove, and a second shear key member disposed adjacent to the first shear key member in the groove, the second shear key member having an axially projecting shoulder, its outer circumferential surface being in contact with an inner circumferential surface of the casing. The first and second shear key members are circumferentially segmented respectively into three or more members, and each member is radially fixed to the casing but not axially fastened to each other, to allow slight displacement between the first and second shear key members by a shear force.

End wall closure apparatus

A hydrogen compressor system comprises a hydrogen generating apparatus for generating hydrogen gas to be supplied to a fuel cell vehicle and a multi-stage reciprocating compressor for pressurizing the hydrogen gas generated by the hydrogen generating apparatus. High pressure tanks having maximum use pressure of 20 MPa are connected to middle stages of the multi-stage reciprocating compressor by gas supplying lines via valves. By opening/closing the valves, hydrogen gas in the high pressure tanks can be selectively supplied to the middle stages of the multi-stage reciprocating compressor.

Hydrogen compressor system

A reciprocating compressor includes: a low-pressure stage compression part for compressing low-pressure working gas supplied from a supply source; two high-pressure stage compression parts for compressing the working gas compressed by the low-pressure stage compression part at two stages; and a crank mechanism for driving the low-pressure stage compression part and the high-pressure stage compression parts. The two high-pressure stage compression parts each have a plunger and a cylinder and are arranged on both sides of the crank mechanism in such a way as to extend coaxially opposite to each other. The low-pressure stage compression part has a piston and a cylinder and is located in the middle of the two high-pressure stage compression parts. The crank mechanism, the low-pressure stage compression part, and the two high-pressure stage compression parts are substantially located in the same plane.

Reciprocating compressor

A turbo-compressor being driven by an electric motor has an inlet guide vane and a blow-off valve. The surge limit line of the compressor is amended depending upon seasonal changes of temperature and pressure of a working gas to be sucked into the compressor. Upon the basis of the surge limit line amended, the minimum opening of the inlet guide vale is altered, thereby reducing the driving power or force of the compressor.

Turbo compressor and method of operating the turbo compressor

A heat exchanger used in a screw air compressor has a low temperature chamber through which low temperature fluid flows and a high temperature chamber through which high temperature fluid flows. The low temperature chamber and the high temperature chamber are separated by a partition plate. The high temperature chambers and the low temperature chambers are alternately arranged in layers, so that the low temperature chambers are disposed at both ends in a layered direction. Additionally, the flowing direction of the low temperature fluid in the low temperature chambers and the flowing direction of the high temperature fluid in the high temperature chambers are substantially orthogonal to each other.

Heat exchanger for air compressor

A reciprocating compressor, being small-sized and compact, for compressing hydrogen gas to be used in a fuel-cell car, has a crankshaft, to which an end of a connecting rod is connected. The other end of the connecting rod is connected to a crosshead. To the crosshead are connected a pair of shafts, each extending in directions opposing to each other. To each of the shafts is connected a plunger. The each plunger is received within a cylinder at the tip portion thereof. A pair of plungers moves reciprocally on an almost same axis, and the crosshead is formed in one body.

A turbo compressor, comprising two (2) pieces of rotation shafts, being disposed in parallel with each other, wherein impellers are attached on both ends of one of the rotation shafts, thereby to build up a first-stage compressor and a second-stage compressor, while an impeller on one end of the other rotation shaft, thereby to build up a third-stage compressor. In a lower side of each of the compressors, an intercooler and an after-cooler are disposed in alignment with, for cooling down an operation gas compressed in each stage. The operation gas is guided into the first-stage compressor on a side opposing to a motor, into the second-stage compressor on a side of the motor, and into the third-stage compressor on the side opposing to the motor, in the order thereof.

Turbo compressor

A package-type screw compressor includes a low-pressure stage state compressor and a high-pressure stage compressor. Motive power is transmitted from an electric motor to the two compressors via a speed increaser. The discharge gas, compressed and heated to a high temperature by the low-pressure stage compressor, is cooled by an intercooler. The discharge gas, compressed and heated to a high temperature by the high-pressure stage compressor, is cooled by an aftercooler. A casing of the intercooler and that of the aftercooler are formed integrally with a speed increaser casing, reducing the number of component parts. A cooler portion, formed by the intercooler and the aftercooler, is spaced from the speed increaser casing, thereby preventing heat, produced by the compressed air, from being transmitted to the speed increaser casing.

Screw compressor

There is provided a control method capable of stably rotating a synchronous motor synchronously with an output frequency even when a phase error between a real rotary axis and a control rotary axis is large. In a phase error operating unit, from the magnitude of the motor current, the magnitude of the motor voltage, the phase difference between the motor current and the motor voltage, and the motor constants, the phase difference between the motor current and the real rotary axis is determined as the first phase difference, and the phase difference between the motor current and the virtual rotary axis is determined as the second phase difference. The difference between the first and second phase differences is defined as the phase error, and the estimation position is so modified as to make the phase error zero.

Position-sensorless controlling method of synchronous motor

A very high speed permanent magnet type electric rotating machine, in which loss generated on a rotor is small to achieve high efficiency on an air generating source even when driven by an inverter operating at a fundamental frequency of at least several hundreds of Hz and in which a reactor is inserted between the inverter and a permanent magnet type synchronous motor, and content percentages of components of harmonic current supplied to the permanent magnet type synchronous motor are adjusted such that when a content percentage of a fundamental wave is 100%, a content percentage B of a seventh order component is at most 10% and a total content percentage is made equal to or less than a certain value so as to satisfy the relationship (A<C<B) where A is a content percentage of a fifth order component, B is a content percentage of a seventh order component thereof, and C is a content percentage of a ninth order component thereof, thereby enabling realizing a very high speed permanent magnet type electric rotating machine system, in which harmonic loss of neodymium magnets as well as harmonic loss of a shaft is greatly reduced and loss of the rotor can be reduced to several hundreds of W.

Very high permanent magnet type electric rotating machine system

In a fluid machine such as multistage centrifugal compressor, the pressure of a working fluid is raised with the rotation of a impeller. A shaft sealing device is mounted at the end of the rotary shaft in order to prevent the working gas of the raised pressure from leaking out of the fluid machine and then polluting the surroundings. In a case where the fluid machine operates to rotate at high speed, a labyrinth sealing device is employed for the purpose of reducing a frictional loss in the shaft sealing device. The labyrinth sealing device includes a plurality of stages of labyrinth fins which are formed on a casing or the rotary shaft, and a layer of abradable coating to-be-bitten which is formed in the surface part of the rotary shaft or the casing opposing to the labyrinth fins. The clearances between the labyrinth fins and the rotary shaft or the casing are made narrower on the low-pressure side of the labyrinth sealing device than on the high-pressure side thereof. Thus, the fluid machine is run with the minimum clearance. Moreover, even when the coating layer has been lost in touch with the labyrinth fin or by peeling off, the labyrinth fin on the low-pressure side acts as a labyrinth seal.

Labyrinth sealing device, and fluid machine providing the same

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Chiyoda, Japan

Haruo Miura