Theory Analysis And Experimental Study About Axial Force Automatically Balance Of Floating Impeller

Pumps are applied very extensively and play a very important role. In the Machines of Pump, axial force is the necessary and considered factor in pump's design and run. Information from the large amount of documentation, it is easy to see that the existing balance devices are subject to a certain degree restrictions in the balance capacity and the application scope. And the study of axial thrust formula has always been weak in the design of pump. A new type floating impeller device is proposed by tracking the difficult and hot question in the water pumps industry. We attempt to seek the distributing of velocity and pressure through sampling the equation of Navier-Stokes. For the floating impeller in the project provide the extensive application of the theoretical basis.At first, this article introduces internal and oversea search actuality about axial power four aspects, such as the reasons of axial power's happening, the common methods of balancing axial power, the calculating way of axial power. Our search make sure that theory search on liquid pressure distributing of pump cavity is not enough thorough, and the equation of axial power is more, and the computing values calculated according to different equation have much difference. All of this makes designer bemused. This article brings forward the main search contents of mine based on the above search.Secondly, this paper introduces recent balance device of progress. Such as adding balancing hole on impeller's hub, symmetrical collocation of impeller of segmental type pump, balance disc, balance drum, and the associated action with the balance disc and the balance drum. Some new way about balancing axial power is put forward in recent years, and these are based on improving on back vane, balance disc, balance drum or aimed at certain type of pump. These equipments also receipted good balancing effect.Thirdly, we spread our theory analysis on axial force of centrifugal pump with floating impeller and self-poise ability. Balance cavity is long in radial direction and short in axial direction. Aimed at this characteristic, we build up flow model for liquid in balance cavity, and educe simple Navier-Stokes using antitheses by quantum, and obtain the relation equation of pressure in balance cavity along radial direction which it's the number of function. Our search based on 3BA-6 single stage centrifugal pump obtain that the change of P is the one of the key technology to achieve floating impeller's adjusting by itself through ration analysis on the pressure in balance cavity. Influence factor of pressure's variety is the ratio k|- of the total area of balance hole of impeller and the area of back joint ring's clearance d₁. If k≥2, the variety of pressure P in balance cavity is smoothness. Therefore, we could think that the pressure P in balance cavity is not change and its value is lift's 5-10% in corresponding working condition. This conclusion is instructional signification for design of axial power structure of centrifugal pumps with floating impeller and self-poise ability.In the end, the pressure of balance cavity of 3BA-6 single stage single-suction volute pump was measured. The result showed that the pressure of balance cavity changes with the flow rate on condition that the packing ring diameters are equal and the rear packing ring diameter is enlarged. According to the experimental data, the pressure of balance cavity in the chamber were analyzed, In order to facilitate analysis of the body cavity pressure similar balance with the pressure coefficient than the area and two dimensionless parameters. Solve a similar balance of the pressure in the cavity of the problem, the conclusions of a high practical value.