DE7921534U1 - CENTRIFUGAL PUMP FLOW CONTROL BY AIR SUPPLY - Google Patents

Description

φ • t

»I ·

Kreleel pump flow control by means of air supply

The invention relates to a device for automatic, level-dependent delivery flow control of a centrifugal pump, which consists of sucks in a pump sump with a changing water level, the delivery flow being fed into the suction pipe by means of an air supply the centrifugal pump is regulated.

Pump stations with strongly fluctuating water supply, e.g. from Weather-dependent sewage pumping stations are used to adapt to the amount of water that occurs large pump sump operated as a water collection basin. In the case of a small water collection basin, the pumps were in very pumping away the water for a short time, so that as a result of the falling water level there is an inadmissibly high switching frequency of the Electric motor driven pumps would result.

From DE-PS 512 OO3 a system is known in which means throttled air supply in the suction pipe of a pump, suction heights greater than 10 meters should be achieved. To this end Several pipes are arranged in the pump sump, which open into the suction pipe at different heights and with the Atmosphere related. This ensures a continuous supply of air.

·· »· Il llfl lit · Sf

It 'It *

l Il I ··

ι t

I I ·

From the essay by Professor Dr. M.!. Kosmowskl and Dipl.-Ing. B * Wunderlich "Operating behavior of a centrifugal pump in the flow control by air supply", published in "Pumps and Compressor Information", 1978, Issue 2, Rare 15-20, It is known that a Krelsel pump control by supplying air into the suction pipe has economic advantages over the known Throttle control offers.

The invention is based on the object of creating a device which, in a simple manner, is an automatic, reliable Control of a centrifugal pump by means of air supply ensures.

The object is achieved according to the invention in that a standpipe, whose outer surface is perforated and whose front openings are closed, installed vertically in the pump sump and with the suction pipe of the centrifugal pump is connected, the length of the standpipe is dimensioned such that it is in the pump sump Occurring water level differences covered, By means of this measure it is achieved that over the respective water level released bores just enough air is sucked into the suction pipe that the pump characteristic curve as a result of the free Air content of the water is shifted to the right amount to a smaller flow.

• MW ·· t * * t

For better adaptation of such a standpipe to different types of centrifugal pump, one embodiment of the invention provides that the standpipe consists of two or more perforated pipe pieces that can be plugged into one another and rotated against one another. By twisting the perforated tubes with respect to one another, the holes can be set between 0% and 100% opening and the respective pump can thus be set accordingly on the basis of the known air control characteristics.

To avoid possible contamination of these bores, a further embodiment of the invention provides that the Standpipe is surrounded by a top and bottom closed cylindrical sieve of large diameter.

The invention is illustrated in an exemplary embodiment and is described in more detail below. It show the

1 shows a pumping station equipped with the subject matter of the invention and the

Fig. 2 shows the standpipe in an enlarged view.

t I

■ I
■ »1 SI

• · ^β Οΐ "· · · ·

In Fig. 1, a pump 2 is installed in a pump sump 1, which drives a motor 3 and conveys the In a pipeline, via a line 5 the suction mouth 6 of the pump 2 is connected to the standpipe 7 designed according to the invention. The lateral surfaces of the upright tube have a plurality of holes and the standpipe and its holes are surrounded by a contamination protection screen. 9

2 shows a standpipe 7, which consists of two pipe sections 10, 11 which are inserted into one another and rotatable with respect to one another. The respective degree of opening of the perforation can be determined by rotating the two pieces of pipe accordingly the amount of air 12 being drawn in in each case can be adapted. Because depending on how high the water level 13 in the pump sump Is, more or fewer holes 8 of the standpipe 7 are released and thus a larger or smaller amount of air <7 in the Suction pipe fed to the pump and thus affects the delivery rate of the pump.

··>> t III St

• · · ·> 1 t V ■ ■ ■ ·

** · t i * ■■ »■

Claims (3)

• · ■ · ft * Klein, Schanzlin & Becker Aktiengesellschaft sayings . Device for automatic, level-dependent flow control a centrifugal pump which sucks in from a pump sump with a changing water level, wherein the flow of the centrifugal pump is regulated by means of an air supply into the suction pipe, characterized in that that a standpipe (7), the outer surface of which is perforated and the end openings of which are closed, into the pump sump (1) installed vertically and connected to the suction pipe of the centrifugal pump (2), the length of the standpipe (7) such is dimensioned so that it covers the water level differences occurring in the pump sump (1). 2. Device according to claim 1, characterized in that the Standpipe (7) made of two or more perforated pipe sections (10, 11) that can be plugged into one another and rotated against one another consists. • 1 * 1 I · Il I ··· »··« ** • · ι · ι 11 t · * ■ ·· I · t · t ff · I 1 I ait · »· 3. Device according to claims 1 and 2, characterized in that that the standpipe (7) is surrounded by a large diameter cylindrical sieve (9) closed at the top and bottom.