Abstract: A monitoring method for wastewater pump station performance and output, which method is capable of detecting an operating malfunction of the wastewater pump station such as a clog or leak within the pump, piping network or valves, or an output reduction due to pump wear. A monitoring apparatus placed at the wastewater pump staion performs continual monitoring of pump output values based on rates of rise of liquid level during pump non-run periods, time periods for the pump to reduce levels and resulting volume changes and at a controlled moment compares the values with measured reference values.

Abstract: An impeller for a pump, especially a vortex pump, provided with one or more straight or curved vanes arranged radially. Vortex pumps are used e.g. for pumping sewage, for which purpose they are well adapted. However, a drawback with such pumps known so far has been a rather low efficiency and a low lift curve. In the vortex pump of the invention, this problem is eliminated by providing the edges of the vanes with flanges essentially perpendicular to the vane surface.

Abstract: An impeller in a pump, in particular a sewage pump, the passage of which is required to have a given transmission capacity for transmitting the impurities present in the sewage water. When small volumetric flows are being pumped at great delivery lift, it would be advantageous, with a view to achieving good efficiency, to make the passage narrower than the inlet aperture, but up to date it has not been possible to do this without impairing the transmission capacity. In the impeller of the invention, this has been solved in that for achieving sufficient transmission capacity one wider point has been provided in the passage, located between the inlet and outlet margins of the impeller blade.

Abstract: A centrifugal pump with a housing which has circular shape in the direction of the circumference and which has on its circumference an exit tube commencing at an exit port tangentially with reference to the flow, where the length of the exit port in the direction of the housing's circumference is about .pi./4R and where the outer wall of the exit tube constitutes a diverging bulge on outward transition from the circumference. The outer wall of the exit tube, projecting under an angle about 45 degrees from the circumference of the housing, consists of an arc having the center of its radius (r) approximately at the juncture of the opposite wall of the exit tube and the housing circumference.

Abstract: Pump means comprising a pump and a motor, combined to constitute a pump unit for submersion in a liquid, and a pump delivery pipe and a vertical guide track both fixedly mounted in a liquid container, such as a sewage weill for instance, the latter guiding the pump unit and enabling it to be lowered into the liquid tank so that the delivery port of the pump will connect with the delivery pipe, and the pump unit having been fitted with a bipartite slide carried on the guide track. The guide track comprises two guides and that the slide comprises two lower projections and two upper projections, and that the slide has been so connected to the delivery aperture of the pump that the lower projections are located below and the upper projections above the delivery port.

Abstract: A vacuum sewage system, comprising a collection tank, in which the sewer waste arrives with the aid of vacuum through an entrance pipe and from which it departs from time to time through an exit pipe. The arrival and removal of the sewer waste has been arranged to take place with the aid of one pump. The entrance pipe terminates within the collection tank at a minor distance from the intake aperture of the pump.

Abstract: Means for carrying a cable through a wall, for instance through the wall of the motor of a submerged pump, said means comprising a sealing rubber ring encircling the cable and which is tightened up with an annular sleeve to give a watertight seal between the motor wall and the cable. Between the sleeve and the wall has been mounted a tightening ring encircling the cable, this ring carrying members which bend towards the cable in connection with the tightening operation.

Abstract: A cistern pumping plant having within a cistern at least one pump which for the purpose of maintenance and repairs is liftable along guides up onto a servicing platform in the cistern. The servicing platform and/or a part thereof is a plate hinged to the cistern and turnable to an opened position.

Abstract: Seal for the purpose of carrying a rotating shaft throught a wall and which comprises a rotating seal ring and a stationary seal ring abutting thereagainst, whereof one has been connected with the shaft and the other with the wall and whereof one is located at the end of a rubber bellows producing an axial sealing pressure. Within the wall of the rubber bellows there is at least one metal pin, which is positioned obliquely with reference to the shaft.