IL98439A - Vertical turbine pumps - Google Patents

Description

VERTICAL TURBINE PUMPS VERTICAL TURBINE PUMP The present invention relates to fluid turbine work/power machines, particularly vertical turbine water pumps which are mostly used to raise water from subterranean aquifers, the water being used for municipal or agricultural purposes.

Conventional vertical turbine pumps usually comprise, downstream of a suction inlet, a series of rotating vane impellers and stator turbine units, constituting pump stages arranged in tandem for priming and/or pumping the water via a pipe column up to ground level. The impellers are coupled to and driven by a vertical shaft which extends upwards of the discharge pump head housing. The shaft is rotated by suitable drivers such as an electric motor.

Several disadvantages have been recognized, relating to the construction and efficiency characteristics of conventional vertical turbine pumps. Firstly, the water expelled from the discharge pump head does not have,— sufficient pressure to be delivered further along the line directly to the consumer. This, of course, depends on the number of pump stages employed and the head (depth) of the pumped water level. In any event, one or more booster pumps, located downstream at ground level, are usually required to further increase the pressure of the water so that it can be delivered via the pipeline to the consumer .

However, the overall mechanical and hydraulic losses in the water supply system are also increased..

A further disadvantage lies in the fact that the whole weight of the vertical turbine pump series and driving shaft, as well as the hydraulic reaction force of the raised water, are completely suspended on thrust bearings supporting the drive shaft. This results in large vertical forces on the thrust bearing, which, in turn, cause friction losses, and uncontrolled elongations and displacement in the shaft with resultant increases in maintenance and repair operations.

In order to decrease the vertical shaft displacements it was customary to use a hollow shaft — rather than a solid shaft. However, such hollow shafts are less resistant to vibration, and again, detrimentally affect the operation of the system. Thus, for example, the vibration of the shaft and the general instability of the driving system present difficulties with regard to the proper sealing required along the shaft.

It is thus the general object of the invention to provide a vertical turbine pump that will overcome some of the above listed and other deficiencies of the conventional pumps .

It is a further object of the invention to provide a turbine pump with an inherently generated force component oppositely directed to — and thereby partly neutralizing — the gravity and reaction forces to which the shaft suspension/driving assembly is normally subjected.

It is a still further object of the invention to reduce the need for an extra, downstream booster pump for delivering the water after reaching the ground level.

It is a still further object of the invention to substitute such booster pump with an integrally installed pumping stage.

It is a still further object of the invention to incorporate an additional, high pressure top vane impeller with it's inlet directed at 180° relative to the vertical pump impellers driven by one and the same shaft, so as to increase the pressure and thus lift the water to the outlet of the pump.

It is a still further object of the invention to allow the use of a solid shaft in the system.

Thus, according to the general aspect of the invention, there, is provided a vertical line shaft turbine fluid pump comprising one or more stages, installed in tandem on and driven by the said shaft, for raising and delivering the fluid up to a discharge head outlet via a column pipe, characterized by a double volute turbine pump unit installed on and driven by the said shaft, whereby the fluid delivered from the column pipe into the double volute turbine pump is pressurized through the discharge head outlet in a direction tangential relative to the said shaft axis.

The double volute turbine pump preferably comprises an upward facing high pressure top vane impeller surrounded by a double volute stator housing so that the fluid is delivered to the impeller from above, preferably through a spherical configured conduit which envelopes or circumscribes the stator housing.

Further constructional details and advantages of the invention will be more clearly understood and appreciated in the light of the ensuing description of a preferred embodiment thereof, given by way of example only, with reference the accompanying drawings, wherein: Fig. 1 is an axial, cross-sectional view of a vertical pump assembly, featuring the characteristics of the present invention; and Fig 2 is a cross-section (on an an enlarged scale) taken along line II-II of Fig. 1.

Referring to Fig. 1, as shown, the vertical pump assembly comprises a suction strainer 1 connected to suction bowl 2 leading to a first vane impeller 3 connected in tandem via impeller taper lock 4 and diffusor vane bowl 6 to a second vane impeller 7. The two-stage pumping effect of the impellers 3 and 7 pressurize the water through second diffusor vane bowl 8 into column pipe 9, which is made long enough to reach up to upper mounting or support level marked L. So far, the turbine pump construction does not differ from the conventional design, and therefore need not be described in further detail.

Above the ground or support level Lf a pump discharge head 10 is provided which accommodates one or several generally spherical conduits 11 merging from the column pipe 9 to lead the pumped water around an additional top high pressure reaction vane reaction impeller 12 with its associated double volute housing_j.3,. Hence, inlet 14 of the reaction impeller 12 is from above, so that water is delivered by the vanes in a generally radial direction into the spiral conduits of the double pump outlet 15 (see Fig.

A vertical shaft 16 is provided as known, coupled directly, to an electric motor 17 by thrust bearing 18 (partly shown), the shaft extending downwards through stuffing box seal 19, provides driving coupling to the impeller 12 and downwards to the vane impellers 3 and, 7 of the vertical turbine pump. thus evident that the water primed by the vertical impellers 3 and 7 ( in case only two such priming turbines are provided) become boosted by the additional high pressure top vane impeller 12 and is discharged in a direction generally tangential to the vertical (i.e., the axis of the shaft 16).

It will be also appreciated that an upwardly directed hydraulic reaction force is generated by the impeller 12, acting therefore to neutralize or oppose the hydraulic reaction forces generated by the 3" and 7 as well as gravity force of the depending shaft and the assemblies attached thereto including its self weight.

It is in this manner that a hydraulically more balanced construction is attained, allowing less robust and heavy-duty thrust bearing to be employed; it will also allow the use of solid shaft since its self-weight is also neutralized.

This, in turn, will contribute to lessen vibrations and other dynamic loads generated during the operation of the pump.

Furthermore, there will be no need for an additional booster or subsequent pressurizing pumping stages downstream of the discharge head pump housing, resulting in a less costly installation.

Those skilled in the art to which the present invention pertains, will readily appreciate that numerous changes , modifications and variations may be applied to the invention as heretofore exemplified, without departing from its scope, as defined in and by the appended claims. Thus it would be readily understood that, by reversing the direction of the water (or other fluid), the installation may be converted into a power machine (for example, an electric generator) .

Claims (2)

i 098439/2 WHAT IS CLAIMED IS:

1. A fluid supply pumping installation comprising: - a motor located at substantially^ ground level; - a shaft coupled to the motor in suspension, extending down to a fluid reservoir level; ,one or more axial turbine pump units installed in tandem, coupled to and driven by the said shaft to pump the fluid upwards; - a column pipe surrounding the said shaft through which the pump fluid is raised; ( - a double volute radial turbine pump unit having an upwards facing high pressure top vane impeller coupled to the said shaft below the motor; - conduit means coupled to the column pipe so that the fluid pumped by the axial turbine pump unit(s) is delivered to the impeller from above; and - a fixedly mounted double volute stator housing operating with the said impeller so that the fluid is pressurized and discharged in a tangential direction relative to the vertical, thereby generating an upwardly directed force applied to the shaft by; said impeller, at least partly relieving the reaction force and/or the self-weight of the axial turbine unit(s).

2. The installation as claimed in Claim 1 wherein the said conduit means comprise a spherical passage formed in the stator housing. a 098439/2 The installation as claimed in Claim 1 wherein the motor is an .electric motor . The installation as claimed in Claim 1 wherein the shaft is solid. The fluid supply pumping installation substantially as hereinbefore described with reference to the accompanying drawings. For the Applicants, DANIEL FREIMANN, Adv. 4