Rotary pumps rotors

Kreisel-pumpe, /. centrifugal pump rotary pump, -rad, n. turbine turbine rotor, turbine impeller, -verdichter, m. turbocompres-sor. 

Rotary pumps forcibly transfer liquid through the action of rotating gears, lobes, vanes, screws etc, which operate inside a rigid container. Normally, pumping rates are varied by changing the rotational speed of the rotor. Rotary pumps do not require valves in order to operate. 

Another form of positive-acting rotary pump is the single-screw extruder pump typified by the Mono-piunp, illustrated in Figures 3.32 and 3.33. A specially shaped metal helical-rotor revolves eccentrically within a resilient rubber or plastic double-helix, thus creating a continuous forming cavity which progresses towards the discharge of the piunp. A continuous seal is created... 

More recently, HNP Mikrosysteme GmbH [14] has commercialized a type of rotary pump called micro annular gear pump. This t3q>e of pump is a positive displacement pump with an externally toothed rotor and internally toothed ring, which are assembled with a small eccentricity of their rotation axes with respect to each other. The rotation of the internal rotor forces the fluid pockets which are interlocked between two gears to flow. The pump flow rates vary from product to product, but are in a range of 1 pL/h to 1.2 1/min. Advantages of this product include accurate control of flow rate and minimum pulsation in delivery. 

In addition to the intense internal current of liquid continuously penetrating the polymer support inside the spinning rotor, an external flow can be diverted since the mode of action in the vessel is comparable to a rotary pump. In this way external flow cells can be circulated with reaction solutions from the centrifugal reactor without any additional pump. Hereby, the alterations of concentrations in the circulating solutions caused by consumption of reagents or liberation of molecules cleaved from the gel support can be measured directly by flow photometry (UV, IR, conductivity, etc.) and recorded continuously. On opening an outlet valve on the bottom, the reactor is emptied rapidly and completely by spinning off. 

Bent rotor shaft on rotary pump. Repair or replace damaged shaft. 

Positive Pumps. Positive pumps employed by the food industry have a rotating cavity between two lobes, two gears that rotate in opposite directions, or a crescent or stationary cavity and a rotor. Rotary positive pumps operate at relatively low speed. Fluid enters the cavity by gravity flow or from a centrifugal pump. The positive pump also may use a reciprocating cavity, and may be a plunger or piston pump. These pumps are not truly positive with respect to displacement, but are used for metering product flow. 

A potential problem for rotary valve usage is that they tend to pull material preferentially from the upside of the valve, which can affect the mass flow pattern. Another problem is that once soHd drops from the vane, the air or gas that replaces it is often pumped back up into the bin. In addition, air can leak around the valve rotor. Such air flows can decrease the soflds flow rates and/or cause flooding problems. A vertical section shown in Figure 13 can alleviate the preferential flow problem because the flow channel expands in this area, usually opening up to the full outlet. To rectify the countercurrent air flow problem, a vent line helps to take the air away to a dust collector or at least back into the top of the bin. 

Rotary-Blower Pumps. This type of pump employs two interlocking rotors to trap and compress gases. The rotors are prevented from... 

Rotary Locations of measurement points for rotary positive-displacement pumps should be based on the same logic as in-line centrifugal pumps. The primary (X-axis) radial measurement should be taken in the plane opposite the discharge port. The secondary (Y-axis) radial should be at 90° to the primary and in the direction of the rotor s rotation. 

The sequence of rotor assembly and balance correction shall follow ISO 5406. For balancing, the rotor does not include the pump half coupling hub or the rotary units of the mechanical seals. 

Rotary vane pumps (see also Figs. 2.5 and 2.6) consist of a cylindrical housing (pump-ing ring) (1) in which an eccentrically suspended and slotted rotor (2) turns in the direction of the arrow. The rotor has vanes (16) w/hich are forced outwards usually by centrifugal force but also by springs so that... 

A Roots vacuum pump (see Fig. 2.17) Is a rotary positive-displacement type of pump where two symmetrically-shaped Impellers rotate Inside the pump casing past each other In close proximity. The two rotors have a aoss... 

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