LPRE TURBO PUMP UNIT Russian patent published in 2011 - IPC F02K9/48 

FIELD: engines and pumps.

SUBSTANCE: proposed turbo pump unit comprises: 1^st, 2^nd and 3rd impellers of oxidizer and fuel pumps and extra fuel pump. In compliance with this invention, LPRE turbine is a two-stage turbine with two wheels: first and second wheels fitted on internal and external shafts, respectively. Oxidiser and fuel radial-flow pumps incorporate screws fitted ahead of impellers. Note here that external shaft is coupled with all impellers, while intermediate shaft is coupled via magnetic couplings with screws. Fuel pump and extra fuel pump are communicated via pipeline. Turbine second stage wheel features diametre smaller than that of turbine first stage wheel. Lubricant bypass channel is made inside outer shaft to lube bearings wherein aforesaid shafts run. Faces of turbine wheels and radial flow impellers have annular seals to form unloading chambers.

EFFECT: improved cavitation properties and all shafted relieved of axial load.

4 cl, 2 dwg