Abstract: A pump impeller of a centrifugal- or a half axial type meant to pump liquids, mainly sewage water, the pump impeller including a hub provided with one or several vanes, the leading edges of which being strongly swept backwards. The size of the sweep angle (.alpha.) varies between 40 and 55 degrees at the connection with the hub, and 60 and 75 degrees at the periphery.

Abstract: A pump of a centrifugal- or a half axial type meant for pumping liquids, mainly sewage water, the pump having a pump housing and a pump impeller. The pump impeller includes a hub provided with one or several vanes, the leading edges of which being strongly swept backwards. Feeding grooves are arranged in the surrounding pump housing in a surface opposed the vanes.

Abstract: A unitarily formed diverter valve assembly for use in liquid chromatography. The valve assembly comprises a plurality of inlet and outlet ports, diverter valve systems, chambers, and a tortuous network of passageways all of which are arranged to accommodate the flow of fluids in a liquid chromatography system. The valve assembly is configured so as to direct the flow of fluid coming from an inlet port through the valve body where it can then be reversibly directed into or out of a chromatography column. On returning from the column, the fluid reenters the valve assembly where it is directed to an outlet port in order to exit the system. The valve assembly can also be configured so as to bypass the column altogether. Since the entire valve assembly is machined out of a single block of material having smooth liquid passageways, and since all flow compartments are shared and fully flushed when a flow-through valve is opened, dead-legs are virtually eliminated from the system.

Abstract: The invention concerns a mixing and aeration unit, especially for waste water treatment and including a submersible axial flow mixer (2), an elongated jet ring (6) with inlet (6a) adjacent the mixer propeller (3) and housing a number of air bubble diffusers (10).

Abstract: A sealing arrangement for a pump including an electric motor/generator and a pump housing, said sealing arrangement including: an intermediate barrier liquid chamber; a mechanical face seal positioned between the pump housing and the intermediate barrier liquid chamber; and, a pumping seal positioned between the intermediate barrier liquid chamber and the electric motor/generator such that air is on a first side thereof and liquid contained in the intermediate barrier liquid chamber is on an oppositely disposed second side thereof, the pumping seal being adapted to repump leakage of liquid from the second side to the first side of the pumping seal.

Abstract: The invention concerns a seal housing for a mechanical seal device. The seal device is arranged within a cavity (6) provided with a spiral notch (11) at its mantle surface for feeding particles in the liquid in a direction away from the seal means (7) and toward an impeller. The spiral notch opening axially toward the impeller.

Abstract: A device (10) for manipulating submerged-operating units (11), such as submersible motor-driven pumps, submersible motor-driven stirrers and the like, has a hoist, by means of which the unit (11) can be brought into a submerged working position and a surfaced maintenance position, wherein the unit (11) is provided with a lifting strap (25) of a coupling unit, whose coupling element (60, 60'), which can be brought into and out of engagement with the lifting strap (25), is provided on a pulling element (48) of the hoist.

Abstract: Scrolls separable radially, to enable cleaning and polishing of the inner surfaces of the throat area, are disclosed. In one of the embodiments, an inner structure of the scroll intrudes into the throat area for selectively reducing the area, in order that flow, pump head, and speed can be matched.

Abstract: A unitarily formed diverter valve assembly for use in liquid chromatography. The valve assembly comprises a plurality of inlet and outlet ports, diverter valve systems, chambers, and a tortuous network of passageways all of which are arranged to accommodate the flow of fluids in a liquid chromatography system. The valve assembly is configured so as to direct the flow of fluid coming from an inlet port through the valve body where it can then be reversibly directed into or out of a chromatography column. On returning from the column, the fluid reenters the valve assembly where it is directed to an outlet port in order to exit the system. The valve assembly can also be configured so as to bypass the column altogether. Since the entire valve assembly is machined out of a single block of material having smooth liquid passageways, and since all flow compartments are shared and fully flushed when a flow-through valve is opened, dead-legs are virtually eliminated from the system.

Abstract: High pressure natural gas enters the regulator at the inlet port and is directed through a filter to a passage in the valve body and into the inner chamber of the valve body. The valve means which controls the high pressure gas as it expands past a valve seat and into the low pressure chamber of the regulator body, is spring mounted in a bushing to prevent undesired vibrations. The expanded and colder low pressure natural gas is directed through a nozzle to the outlet port of the regulator body. The outlet port has a bypass orifice that leads to the diaphragm chamber. Pressure variations in the diaphragm chamber control the movement of the valve means coupled to the diaphragm means.

Abstract: A closed, hollow body has a suspending and tethering, electrical cable joined thereto, the latter conducting electrical power to and from a microswitch confined within the body. A switch actuator is engaged and disengaged by a weight, within the body, the weight being pivotably supported therein, and having a center of gravity which is offset from a central, longitudinal axis of the sensor.

Abstract: The invention concerns a device for mounting and keeping together parts in a submersible pump unit.Two groups of screw joints (15) and (16) respectively are alternatively arranged around the periphery of the pump unit, the first group of said joints (15) connectings the stator housing (8) and the seal housing (4) via a ring (13), while the other group of joints (16) connect said ring (13), said pump housing (5) and a cooling jacket (10) surrounding said stator housing (8).

Abstract: A compact set of circular, wire-formed brushes, within a housing, provides the surfacing upon which, and in which, air bubbles can coalesce for subsequent venting thereof from the housing, and the housing has porting formed therein to accommodate a through-flow of an aqueous solution, of a hydronic system or the like. A sleeve-type diffuser, having a multiplicity of holes formed therein, encloses and supports the set of brushes, and diffuses and distributes the housing-admitted liquid or vapor.

Abstract: A power supply for a variable speed AC motor includes a waveform generator for generating a periodic pulsed waveform according to a desired motor speed, an adjustable source of DC potential, and an inverter coupled to the waveform generator and to the source of DC potential. The inverter provides an AC pulse train to the AC motor, the pulse train having waveform characteristics according to the pulsed waveform generated by the waveform generator to obtain the desired speed. The voltage amplitude of the pulse train provided to the motor is proportional to the DC potential whereby motor currents can be controlled at the desired motor speed by varying the DC potential.

Abstract: A waste water pump station is provided for two submersible pump units which are attached to connection units on the station wall or on a shelf of the wall. The two connection units are attached in a reversed manner with respect to one another making it possible to mount them very close to the wall.

Abstract: A circular body, having a throughgoing orifice, an externally threaded periphery, and a pair of stepped recesses, defines a valve seat for a reciprocating piston. A retaining ring is made fast in one of the recesses, and a seal which contracts upon cooling to the ambient, after having been exposed to elevated temperatures, is set in the other recess. The seal is formed of a composite of plastic in which are dispersed carbon fibers to render the seal resistant to creep. A housing having a pair of chambers formed therein has the orificed body and piston interposed between the chambers for valvingly controlling inter-chamber communication.

Abstract: The invention concerns a device for installation of a mixer in a water tank. The mixer is arranged on the inside of a cover (4) in the tank wall (2) which means that only the electric connection means to the motor have to be sealingly drawn through the wall.

Abstract: A cavity in the housing, which confines the seal therewithin, has an annular wall surface which is modified to direct liquid from the cavity towards the impeller. In one embodiment, the wall surface has a helical land formed therein. In another embodiment, a helical-land forming insert is set within the cavity and in engagement with the wall surface.