Hitachi, Ltd.

Kunio Takada

Kenji Otani

Sadashi Tanaka

Masayuki Yamada

Ryoji Okada

Sumio Sudo

Saburo Maru

Toshihiro Yamada

Mitsuaki Haneda

Kooji Aizawa

Akira Manabe

Kenji Fujii

Seiji Miura

Akira Yamaguchi

Katsutoshi Nii

Fuminobu Komura

Koichi Homma

Kohji Aizawa

Yoshiaki Chiba

Kooju Aizawa

Yutaka Shimada

Shigenobu Nagasawa

Shiro Matsui

A drainage water pumping system. A number of drainage pumps are positioned at two different levels. Drainage water flowing into a drainage water pumping system from an underground inflow main pipeline is pumped to a discharge destination. Preferably the drainage pumps installed at the lower installation level have a high pump head and a small capacity, while the drainage pumps installed at the higher installation level have a low pump head and a large capacity. The drainage pumps can be in a circular arrangement with a congregated delivery pipeline installed lengthwise at the center of the circular arrangement and having each of the drainage pumps connected to it.

Drainage water pumping station and method for operating the same

An underground water channel is provided in an underground of a large depth, and rain water and the like flow into this underground channel from flood control channels, conduits and rivers through vertical shafts. A pump well of a pump station is connected to a downstream end of the underground channel, and water flowing into the pump well is discharged by a pump to a discharge tank. The pump is disposed generally at a medium water level of the underground channel, and a lowest water level L.W.L enabling draining is the medium water level of the underground channel. In an open channel flow operation of an open channel-closed channel mixed flow operation, water level of the underground channel is maintained at the lowest water level L.W.L, so that the underground channel is in an open channel condition. In the closed channel flow operation, the underground channel is fully filled with water, and further water level rises into the vertical shafts, so that the underground channel is in a closed channel condition. By changing an outflow factor in accordance with rainfall patterns, the rate of flow into the vertical shafts can be accurately estimated, so that the large-depth underground drainage facility can be run in a stable manner.

Large-depth underground drainage facility and method of running same

Disclosed is a bearing unit which can be used in a drainage pump operated without supply of clean water or a hydraulic pump, which exhibits excellent wear resistance against water containing earth and sand and satisfactory assembling facility, and a method of manufacturing the bearing unit. The contact surface of a bearing made of stainless steel and/or that of a sleeve is applied with a sprayed coating, the main component of which is WC, and which contains one or more elements selected from a group consisting of nickel, chromium and cobalt as a binder material thereof, or a sprayed coating, the main component of which is Cr.sub.3 C.sub.2, and which contains NiCr as a binder material, after the sprayed coating has been formed, heating at from 300.degree. C. to 550.degree. C. is performed for one hour or longer so that hardness and wear resistance equivalent to those of a WC-12% sintered article is attained.

Bearing unit, drainage pump and hydraulic turbine each incorporating the

A river management system for controllably operating devices of management facilities installed at pluralities of rivers and waterways to manage water volumes in a river network including the pluralities of rivers and waterways. The river management system includes an operation plan database for storing therein a plurality of sets of the contents of operations of the river management facility devices in the form of operation modes when the values of water levels, flow rates, precipitations and change rates thereof at a plurality of points of the river network satisfy predetermined conditions; an operation plan decider, when the values of water levels, flow rates, precipitations and change rates thereof at the points of the river network satisfy the predetermined conditions, for selecting one of the operation modes corresponding to the conditions and determining the operation contents of the river management facility devices; and a monitor/input section for inputting values of water levels, flow rates and precipitations of the points of the river network to the system.

System for cooperatively operating river management facilities

In a drainage pump station, a driving machine has a capacity greater than a shaft power necessary for no-discharge operation of a pump, and during severe flooding the pump is operated at an overload exceeding its design capacity. During maintenance operation water is fed from a river on the delivery side of the pump station into the station. When an inflow of rainwater into the pump station is great the pump is operated at the necessary capacity, when it becomes small the water level is kept above a rated value, and when the inflow rate is zero the pump discharge is increased to a capacity at which sediment can be discharged. A suction blower is disposed at the top of a suction sump and interstage valves are disposed in entrances of vertical shafts to effect efficient ventilation of the underground waterway. A feed channel is operated as a pressure channel and the pump is of variable capacity and the water level in the underground waterway is controlled to be constant.

Drainage pump station and drainage operation method for drainage pump

A plural drainage pumps PH are disposed on the high floor gradation state at the circular shape. A plural drainage pumps PL are disposed on the low floor gradation state at the circular shape. The drainage pump PH disposed on the high floor gradation is installed at the high level. The drainage pump PH is set one having the low pump head and the large capacity in comparison with those of the drainage pump PL disposed on the low floor gradation. An outer shape of an underground pump construction building is formed a circular cone shape spreading toward an upper portion. The discharge water power can be reduced and the construction area for the underground pump construction building can be reduced and further the engineering working amount such as a digging working at the underground can be lessen.

In a ceramic bearing device having a ceramic bearing slidably supporting a sleeve fixed to a pump main shaft, a bearing case mounting the ceramic bearing and a bearing casing elastically supporting the bearing case with rubber, a cylindrical container is fixed to the bearing casing so as to surround the lower surface and the outer peripheral side of the bearing casing, a water storage tank having a return plate in the top end portion being fixed to the pump main shaft so as to surround the cylindrical container, a passage being provided in the cylindrical container, distance pieces being provided between the outer peripheral portion of the bearing casing and the inner peripheral portion of the cylindrical container being provided, a passage being formed in the distance piece.

Method of operating pump and bearing device for pump

A plurality of drainage pumps are disposed on a high floor gradation state in a circular arrangement. A plurality of drainage pumps are disposed on a low floor gradation state in a circular arrangement. The drainage pumps disposed on the high floor gradation are installed at a high level, with the drainage pumps having a low pump head and a large capacity in comparison with the drainage pumps disposed at the low floor gradation. An outer shape of an underground pump construction building is in the form of a circular cone shape spreading toward an upper portion of the underground pump construction building. The amount of power for discharging the drainage can be reduced and the construction area for the underground pump construction building can be reduced thereby minimizing the necessary requirement for installation of the underground pump construction.

Drainage pump and a hydraulic turbine incorporating a bearing member,

Disclosed is a bearing unit which can be used in a drainage pump operated without supply of clean water or a hydraulic pump, which exhibits excellent wear resistance against water containing earth and sand and satisfactory assembling facility, and a method of manufacturing the bearing unit. The contact surface of a bearing made of stainless steel and/or that of a sleeve is applied with a sprayed coating, the main component of which is WC, and which contains one or more elements selected from a group consisting of nickel, chromium and cobalt as a binder material thereof, or a sprayed coating, the main component of which is Cr.sub.3 C.sub.2, and which contains NiCr as a binder material, after the sprayed coating has been formed, heating at from 300.degree. C. to 550.degree. C. is performed for one hour or longer so that hardness and wear resistance equivalent to those of a WC - 12% sintered article is attained.

Growing community of inventors

Ibaraki-ken, Japan

Kunio Takada