STEAM TURBINE DOUBLE-FLOW LOW-PRESSURE CYLINDER Russian patent published in 2017 - IPC F01D25/24 F01D25/30 

FIELD: electricity-producing industry.

SUBSTANCE: low-pressure cylinder is offered (LPC). It is coupled to the inlet nozzle of the condenser and is comprised of the body, of the placed on its ends inlet nozzles, of the labyrinth end seals and of the bladed rotor, which is in resting contact upon the bearings, linked to the generator and comprised of the group of the moist-steam stage of the straight, directed to the generator side steam flow with the exhaust axial-radial manifold and of the group of the moist-steam stage of the reverse-direction flow with the exhaust axial-radial manifold. At the same time, the manifolds are situated within the LPC exhaust nozzle, which is linked to the condenser inlet nozzle, which is under vacuum, and are formed by the pair of ring blades that perform the confusor flow deflection from the axial direction to the radial one. The external blades end with the radial walls that are vertical to the rotation axis and that limit the axial size of the axial-radial manifold exhaust part and form the conjoint axial-radial manifold exhaust part of the both stages groups. Besides of that, the exhaust nozzle and manifold exhaust parts, that are limited by the radial walls and are situated within the exhaust nozzle, are located at the LPC middle part, and the inner strickling line from the flow side is implemented with the right-angled shoulders. The claimed technical solution allows improving the functional efficiency and reliability of the power generating unit and cut down the conversion cost at the expense of the elements' introduction into the construction of the double-flow LPC of the steam turbine. These elements significantly differ the solution from the analogs and prototype and eliminate its operational defects. The implementation of the right-angled shoulders on the inner strickling line of the external ring rotating blade of the axial-radial exhaust manifold eliminates the flow separation from the blade face and allows making the manifold rotating part more compact, thus reducing the axial dimensions and the LPC cost. The manifold exhaust parts, that are limited by the radial walls, that are situated within the LPC exhaust nozzle, which is under vacuum, location at the middle part of the low-pressure cylinder eliminates the air infiltration in the condenser through the end seals.

EFFECT: efficiency is increased, steam condensation on the exhaust parts is eliminated, abrasion in the last stages is eliminated and turbine reliability is enhanced.

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