SU819364A1 - Steam turbine flow-throuth section - Google Patents

Description

(54) FLOW STEAM TURBINE

The invention relates to the field of turbine engineering and can be used, for example, in the low-pressure parts of high-power steam turbines for thermal power plants and nuclear power plants. The flow-through parts of the steam turbine are known, in which the flow behind the lower light brown is divided by a partition into two streams, one of which goes to the last step and the other turns 180 to the upper rune of the penultimate step 1J. Known solutions that have a number of advantages cannot be implemented in modern steam turbines in their dimensions. Closest to the invention by technical essence and the achieved result is the flow-through part 2, containing a two-blond impeller of the last but one stage, the lower Russian of which is communicated through the working fluid with the last-stage guide device directly with the upper-wheel guide through PTZ camera In this case, the pivoting chamber is filled in the form of an annular nipple, in which additional rotary vanes are installed. However, in these devices, it is possible to turn the flow with a low level of losses; they cannot be implemented in modern steam turbines in admissible axial ga baritas. The purpose of the invention is to reduce the axial dimensions and increase efficiency. To achieve this, in a flow-through part containing a two-light impeller of the last but one stage, the lower Russian of which is communicated through the working fluid with the last-stage guide apparatus and directly with the upper-wheel guide device The entrance part of the turning chamber is made in the form of channels in the blades towards the last stage apparatus. At the same time, the outlet part of the chamber is made in the form of the rear nozzles installed at the inlet to the interscapular channels of the upper apparatus guiding apparatus. FIG. 1 shows the flow through part, longitudinal section; in fig. 2 section A-A of FIG. 1 in FIG. 3 is a section BB of FIG. 1 in FIG. 4- - cross-section, AieB-B of FIG. Ij in FIG. 5 is a view of FIG. one; in fig. 6 - section DD

ig, 5; in fig. 7 - section EE U. 6; in fig. 8 is a flow through | I part of an embodiment with an intermediate chamber in FIG. 9 is a view to FIG. eight; in fig. . 10 - section 3-3 of FIG. 9-, fig. 11 is a cross section of AND-FIG. ten; in fig. 12 is a section to K — K of FIG. ten; on

FIG. 13 is a cross section of an LL fig. ten; in fig. 14 - section MM of the fit. ten; on ig.- 15 - section HH of FIG. ten; in fig. 16 is a cross section of OO of FIG. ten.

The proposed flow-through part (Fig. 1) contains a rotor 1, on which working blades are installed - two-level 2, divided into lower 3 and upper 4 Russ, and the last stage 6. The diaphragm of the last stage has a body, the guide vanes 8 with internal cavities 9, The port has 4 front-facing chambers and 10 openings at the entrance edges (FIG.

2). Interblade channels 11 of the diaphragm 7 of the last step are limited on the upper meridian rim by a composite partition 12 (Fig. 1 and 3).

- Above the radome 13 of the diaphragm 7 (locate the upper russ’s guide apparatus 14 having blades 15. Immersing the cavity of 9 blades of the coB (Inen with interlocking channels 16 directions of the upper apparatus of the rue so that the walls of the 17 blades of 8 are docked with the walls of the 18 blades of the 15

(Fig. 3 and. 4).

Between the elements of the partition 12 of each last-section meleopastral channel 11 and the fairing 13, a slot 19 is made. cavities 9 through holes 23. The holes 21 and 23 are connected by an annular groove 24. fla

The septic rim of the sepiCijero guide machine. The tusk is made holes 25, connected to the chamber 22 (Fig. 1, 6, 7). The entrance edge 26 of the stencil 17 on the side of the internal profile of the blade is extended relative to the other krsmiki 27 in the direction of the two-level working blade 2 (Fig. 2).

In the inner cavities 9, grilles, rotary vanes 28 and 29 with solid profiles, mounted on the walls 17, are installed.

FIG. 8 shows another embodiment of the flow-through part, where a chamber 31 is arranged in front of the upper tier guide vanes 14 with blades 30, connected to the inner cavities 9 of the last runner vanes 8 8 and upper blade tandem ducts 32. The number of blades 0 is greater than the number of blades 8.

The guide vanes 8 of the last stage are made by perforations 10 at their entrance part starting from the partition 33 located between the walls 17 of the cavity 9 (Fig. 10, 13). Before the partition 33, the blade 8 has no holes at the entrance part (Fig. 14). Each ig, interscapular channels 11 of the blades 8 is bounded by streamlined partitions 34 (Fig. 15). Between the partitions 34 and the fairing 13 there are slots 35 connecting the channels 11 with the chamber 31 (Fig. 16). The chamber 31 is connected to the selection chamber 22 by means of the openings 36. Between the walls 17 of the blades 8, a rotary-blade blade 37 is mounted.

When the turbine is operating, the steam expands in the lower russa 3 double. working blades-2 and enters the guide vanes 8 of the diaphragm 7 of the last stage. Part of the steam interscapular channels 11 of diaphragm 7, having expanded into them, passes through a working vanes of the last stage. In the meridional plane, the flow passing through the channels 11 is limited by the diaphragm body and the interstitials 12 installed in each channel.

Another part of the flow passes through the holes 10 at the entrance edges of the guide vanes 8 (the entrance to the rotating chamber) and enters the internal cavities of these vanes, which are the rotating cameras. In the internal cavities 9, for organizing the rotation of the flow with uninterrupted flow and low level of losses, two rows of guide vanes 28 and 29 were installed. Turning in the internal channels, the flow enters the inter-blade channels 16 of the upper-roller guide apparatus 14 with blades 15, enters them and enters the working vanes of the upper 4 rus. Thus, the bypass and rotation of a part of the flow to the upper rus is carried out through the internal cavities of the last-stage guide vanes connected to the interscapular channels of the upper-rus stage. Regenerative selection is carried out from both streams: from the stream going to the last stage through the slit 19, the fairing 13 and the barriers 12 and further, through the holes 21 in the rim 20 of the diaphragm into the selection chamber 22 ,. from the flow of the upper tusa through the openings 23 into the selection chamber 22. Moisture flowing through the upper limiting surface of the interscapular channels of the upper trough guide apparatus enters the selection chamber 22 through the drainage openings 25. The inlet edges 26 and 27 of the inlet openings 10 are shifted relative to each other in axial "aravleniya. which ensures that large drops of moisture settle on the inner walls. In another variant of the device sinking out (Fig. 8), in order to independently select the number of guide vanes, the current 30 of the upper and 8 lower ruses (with their unequal mixtures) the flow after the internal cavities 9 enters the common precast distribution chamber 31 and further in the inter-channel canals of 32 directing apparatus 14 of the Upper Rus. In this case, the selection is carried out through the slits 35 into the common chamber 31 and through the openings 36 into the selection chamber 22. The flow separation can be carried out either over the entire height of the inlet part of the blades 8 (Fig. 1, 6), or on a part of its height (Fig. 8, 10). In the latter case, the root zone of the guide vanes 8 is performed in the usual way (Fig. 14), and the flow directed to the rotation is cut off by the partition 33. This completely eliminates the influence of the rotation of the flow to the upper rusa on the work of the root zone of the last step. Thus, the implementation of the proposed device provides - supply of the working fluid to the upper rus with minimum axial dimensions and increased efficiency of the flow through

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Claims (2)

ig. As a result, by reducing the losses in flow turning. 1. Flowing part of a steam turbine, mainly a low pressure cylinder, containing a double-brown overalls of the penultimate stage / lower rus of which is communicated through the working fluid with the last-stage guide apparatus and directly with the upper-rail guide, it differs from By the fact that, in order to reduce the axial dimensions and increase efficiency, the entrance part of the rotating chamber is made in the form of channels in the blades of the guide apparatus of the last stage. . 2. The flow part according to claim 1, wherein the outlet part of the chamber is made in the form of hollow nozzles installed at the entrance to the interscapular channels of the upper guide vanes. Sources of information taken into account in the examination 1. German Patent No. 431915, cl. 14 4/01, 1923. 2.Patent of France No. 536324, cl. 14 from 12, 1922 (prototype). -Iff / 7 eight 22 W fug. $ 8 t / z. / 0 Bvd F Fi9.9 id f: fl L1 (Sug./f / G- / g Fig (I- / I Y / W FIG. J nn fug. 15 IS P.