US1036184A - Stationary diaphragm for steam-turbines. - Google Patents

Description

`o. RBRUMAN, SIATIONARY DIAPHRAGM FOR STEAM TURBINES.

APPMGATION'PILED 11111.2. 1912.

Patented Aug 2O 2 SHEETS-SHEET 1.

Irv/111111111 a I A 0. F. BRUMAN. STATIONARY DIAPHRAGM Pon STEAM TURBINBS. APPLIUATION-IILBD JANLZ, 1912.

1,036,184 Patented Aug-20, 1912.

Q SHEETS-'SHEET 2.

UNITED sTATEs PATENT oFFIoE.

ko'r'ro r. BRUMAN, or BERLIN, GERMANY, AssIGNoR 'ro ROBERT s. 511017Z, oF CHICAGO,

. i STATIONARYDIAPHRAGM FOR STEAM-TURBI'NES.

Specification of Letters Patent. Patented Aug, l20, 1912', -Applicatonled January 2, 1912. Serial No. 668,896. l

To @ZZ whom t may concern:

Be it known that l, OTTO F. BRUMAN,

I citizen of the Republic of Switzerland, re-

siding at Berlin, Germany, have invented a certain new and useful Improvement 1n Stationary Dlaphragms for Steam-Turbines, of which the following is a full, clear,

concise, and exact description.

My invention relates to steam turbines and more lparticularly to the stationary diaphragms which constitute the separating -Walls of theseveral cells or pressure stages the turbine.` Its object is to provide a 'fdraphragm of great rigidity and strength 15" combined with lightness of weight.

A Well-known type of steam turbine. consists of a casing divided into a series lof cells 4-or pressure stages, the separating walls of Which are stationary diaphragms, these diaphragms being located .between the rotating Wheels of the turbine. lGuide vanes or fixed blades are set in each of the diaphragms to form nozzles for directing the steam to therotary blades carried-by the wheels. The steam enters these v cells or pressure stages in succession and gradually decreases in pressure as it travels through the several stages until it 'expands down to exhaust pressure'. The ldiaphrag'ms are therefore subjected not only to a strong steam pressure but to a pressure which is unequal upon the opposite sides of the. several diaphragme. For this reason said diaphragms must possess great lateral strength and .they are therefore ordinarily made either of castiron or cast steel and arevery heavy. A 4 l My invention contemplates a diaphragm made of sheet lmetal so shaped and supported as to possess the requisite lateral strength and stiffness.

The several features of my invention and the advantages arising therefrom maybe more readily understood/by reference to the accompanying drawings, in Which- Figure 1 is a longitudinal cent-ral section through a steam turbine provided with dia-v phragms embodying my invention; Fig. 2 is an enlarged fragmentary front elevation of the diaphragm; Fig..3 is' a radial section of the diaphragm; and Fig. 4 is a fragmentary plan v1ew partly broken away.

Like reference characters refer to like parts throughout the several views.

The main Wall of the diaphragm consists plate, which fitsabout the hub of the shaft 6 is provided lwith an annular flange 31, and the perimeterl of said plate is provided With a circumferential -flange 32. The flanges 31 aud'32 project-in'fopposite directions.

The flange 32 fits tightly within the casing,l 1 and the flange 31 provides the usual clearance for the hub of the shaft 6, at. the same time extending about said. hub in such manner as to reduce to 'a minimum the steam leakage at this point.`

Near its circumference the plate 30 is provided, as usual, with arc-shaped slots 33 to form" passages for steam from one pressure stage to the next succeeding stage. p

The usual stationary blades 34 which are locatedin the slots 33 are supported between annular shells 35, 36 located the one Within the other concentrically of the steam chamber. The forward end of the shell 36 is provided with an annular flange 37 adapted to fit tightly Within the casing 1. From theflange 37 said /shell 36 extends for ap"- proximately one-half of its axial Widthsub stantially parallel to the casing 1 and is then tapered inwardly for a. short distance and is then extended in an axial direction, it being-secured preferably by Welding to the plate 30 immediately above the slots'33. Secured immediately below the slots 33 is the annular shell 35 Which is of less axial Width than the shell 36 in order to provide space in the cellfor the Wheel 27. The

yshell 3 5 tapers toward the shll 36 and then extends axially, parallel with said latter snell, and is secured by Weldingto the plate 30 flush with the arc-shaped openings 33 therein. The shell 35 is braced by an annular -plate 38 which is Welded at its outer circumference to l"the ,shell 35 as indicated at 39 and which, at its inner circumference,

' is welded to the plate 30 as is indicated at 40.

The blades 34 are held bet-Ween the shells 35 and 36, said bladesbeing provided with the usual tangs 34a which fit in slots `in said shell. In order that the shell 36 may be placed about said blades it is split, as lndicated at 36a, and is welded together at this place after the blades have been secured toposition.

As will be seen from Fig. 1 the interior of the casing'l is preferably provided at itsoutlet end witha steady or supporting ring 5 against which the diaphragm of the last pressure stage rests. The flange 37 of this diaphragm constitutes a supporting ring for the diaphragm of the precedin pressure stage, etc'. The shell 36 of the diaphragm of the' first pressure stage rests against the inner plate 29 of the cylinder head. The diaphragms are thus rigidly mounted so as to mutually strengthen each other. The

plate` 38 not only braces the shell 35 but gives added strength and rigidity to the efficiency combined with cheapness. of con-p struction.

Matter shown and described but not claimed herein forms the subject matter of my co-pending applications.

I claim:

1. In a steam turbine, a diaphragm comi prising a sheet metal plate provided 'near its circumference with arc-shaped slots, two concentric sheet metal shells secured to said plate upon opposite sides of said slots, and

I guide vanes secured between said shells.

2. In a steam turbine,a diaphra comprisin a sheet metal plate of dis ed' form provi ed`at its center with an openlng having a flange thereabout' extending rearwardly from said plate and provided at its circumference with an annular flange ex tending parallel and in an opposite direction to said first mentioned flange, said plate being provided vnear its circumference with arc-shaped slots, two concentric sheet metal plate upon opposite sides of said slots, said l shellsv tapering toward each other to pro-I vide Ia steam passageway of gradually tapering cross-section, and guide vanes securedl between said shells. v

4. In a steam turbine, a diaphragm comprising a sheet metal plate of dished form provided at its center with an opening hav ing a flange thereabout extending rearwardly from said plate and provided at its circumference with arc-shaped slots, -two concentric tapering sheet metal shells secured upon opposite sides of said slots and forming between them a converging steam passage. and guide vanes secured between said shells. i

In a steam turbine, a diaphragm comprising a sheet metal plate provided near its circumference with arc-shaped slots, two concentric sheet metal shells secured to said plate upon opposite sides of said slots7-said shells being provided adjacent said slots with parallel walls and being also provided with tapering walls converging toward said parallel walls, and guide Yanes secured between said shells.

In witness whereof, I hereunto subscribe my name this 4th day of December, A. D.,

OTTO F. BRUMAN. Vitnesses:

HENRY HASPER, VVOLDEMAR HAUPT.

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