Hitachi, Ltd.

The Kansai Electric Power Co., Inc.

The Kansai Electric Co., Inc.

Hisao Inoue

Osamu Sugimoto

Ichiro Hitomi

Teiji Horita

Katsutoshi Nii

Takao Kuwabara

Kazuhiko Kawaike

Hiroto Nakagawa

Eizo Kita

Kenzyu Ogiwara

Takeo Hachiya

Mituo Takase

Katsumi Seno

Masayasu Okada

Susumu Naganuma

Koozi Aizawa

The operation of a variable speed electric driven pump turbine is monitored continuously during pumping to detect the operation point of the pump turbine, and to prevent it from falling into a hump characteristic region, which is recognizable on a graph of total dynamic head versus flow rate. Stalling occurs in the hump characteristic region as a result of a partial reverse flow of the water with respect to the runner. When the operation point of the pump turbine approaches the hump characteristic region, a corrective action is taken that includes increasing the output level of the electric driven pump turbine to increase its rotating speed, temporarily.

Variable speed pumping-up system

A lubricated bearing apparatus for a hydraulic machinery has rotary-side ceramic sliding plates disposed in contact with bearing-side ceramic sliding plates. The rotary-side ceramic sliding plates are disposed in receiving grooves of a main shaft sleeve member fixed to the main shaft. The main shaft sleeve member is provided with preventing portions for preventing the rotary-side ceramics sliding plates from being broken by the centrifugal force. Thus, ceramic materials can be used both on the rotary side and the bearing side, thereby lengthening the usable life of the bearing apparatus.

Lubricated bearing apparatus for hydraulic machinery

An end face mechanical shaft seal for use in a hydraulic machine includes a seal ring assembly detachably secured to a seal casing and having a sealing face which makes a sliding and fluid-tight contact with an annular seat face presented by a flange on the rotor shaft. The seal ring assembly is of a cartridge type which includes a ring casing having an annular groove formed in one end surface thereof and a seal ring partly received in the groove and fixed to the ring casing by an adhesive. Each of the ring casing and the seal ring is constituted by a plurality of arcuate sections or segments which are connected together in the circumferential direction.

End face mechanical shaft seal for use in hydraulic machines and seal

Prior to bringing a fluid machine to the condition of spinning reserve for practicing a phase modifier operation or for producing a so-called standby condition which permits immediate switch-over to a power-generating or pumping-up operation, the water level in a runner chamber is forced down by supplying compressed air, and then the runner is driven to rotate in compressed air atmosphere. In this process, the water in a casing is gradually discharged at a rate which is commensurate with the rate of supply of the compressed air so as to thereby prevent leaking of the water in the casing from a guide vane.

Method for controlling the operation of a fluid machine in spinning

There is disclosed a method for starting a pump, wherein when a pump runner effects the idle running in a runner chamber which is filled with compressed air, a water-pumping-up starting instruction is given, then a drain valve is first closed according to the water-pumping-up starting instruction, the aforesaid drain valve being provided in a draft tube for discharging pressurized water from a runner band chamber of the runner chamber; then compressed air in the runner chamber is discharged therefrom; subequently water is charged into the runner chamber; and after water pressure at the adjacent portion of the runner periphery in the runner chamber has been raised to a given level, a by-pass valve and a main valve in a discharge tube and guide vanes are sequentially opened; and a device for automatically substantiating the method.

Method and device for starting pump

In a starting operation of a pump or a pump turbine with high head and large capacity, adjustable guide vanes are fully closed and compressed air is introduced within the runner casing to depress water around the runner. When the runner begins to rotate at a synchroous speed, the guide vanes are excessively opened to an over opening position where no reverse flow of the discharge flow occurs. After the stream of the discharge flow becomes steady, the guide vanes are moved conversely to a predetermined opening position where the maximum flow rate of the pump is obtained with low noise and low vibration. The present invention relates to a starting operation for a pump or a pump turbine with adjustable guide vanes circumferencially arranged around the runner, and more particularly to a starting operation for a pump or a pump turbine which is operated by controlling the opening of the adjustable guide vanes.

Method of starting operation for a pump or a pump turbine

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Hitachi, Japan

Hisao Inoue