US2410804A - Turbine - Google Patents

Description

Nov. E12? i946.' K, SAUMANN 4309304 TURBINE Filed Jan. 13, 1944 2 Sheets-Sheet 1 NW ma W4@ K. @AUMANN TURBIEE Filed Jan. l5, 1944 2 Sheng-Shea?, 2

atented Nov. 12, 1946 anni Ni'rso Karl Baumann, Mere, Knutsford, England, assignor to Metropolitan-Vickers Electrical Company Limited, London, England, a company of Great Britain Application January 18, 1944, Serial No. 518,174

In Great Britain January 19, 1942 Claims.

l ,This invention relates to an internal combustion or gas turbine plant and is notably applicable to the connecting means between the arvent invention, however, has a wider application and is applicable generally where a row or stage of blading such as of an axial flow compressor, and hereinafter referred to as of an outer system, surrounds blading of an inner system with which it has a driving connection, said outer blade row or stage being carried on a foundation ring of light alloy which is connected with one or more stages of the inner system through a driving member conveniently of steel which in partis in the form of a cylinder or a re-entrant cylinder or the like, attached at its radially outermost part to said foundation ring and at its radially innermost part to the blading of the inner system, for instance to the shrouding of the same, the connection being made thereto by providing the radially outermost part of the connecting member with an outward radial ilange integral with a re-entrant cylindrical flange to provide an annular channel into which the edge of the foundation ring is axially inserted and lxed therein such as by a plurality of radial rivets.

The blade roots of the outer system, such as of dovetail form, may be extended in the anal direction beyond the blade so as to be also clamped within the annular channel between the aforesaid steel flanges.

Since the shape of the steel driving member for the foundation ring of the outer system ci blading is chosen to provide some radial llexibility to permit of diierential thermal expansion there will be left a small space between the inner surface of the foundation-ring and the outer surface of the iiexible steel member, and cooling air may be permitted to ilow inthe axial direction through this space by milling a plurality of channels in the extended end of the foundation ring connecting said annular space to a washer-shaped space which may be left within the channel of the steel connecting member, that is between the radial iiange of the latter and the' radial face of the extended end of the foundation ring, whilst holes may be drilled in the radial ange of the steel connecting member to'permit.. the ow of the cooling air to or from this washer-shaped space.

(Cl. B30-116) Where two or more stages oi the outer system are individually driven by corresponding sections of the inner system, for instance constituting a contra-rotating group, an axially extending lip from one driving member may project beneath the neighbouring driving member, and be so formed as to serve as a labyrinth gland therewith.

In the accompanying drawings,

Fig. 1 is a somewhat diagrammatical section vof an embodiment of the present invention, and Fig. 2 is a like view of a second embodiment.

Fig. 3 is a fragmentary section of the foundation ring and adjacent paris of one oi the stages of the outer system of blading; and

Fig. i is a detail section on the line l--i'i in Fig. 3.

For the sake 4of simplicity Figs. i and 2 oi the accompanying drawings are identical with Figs. 8 and 9 respectively of the drawings accom- 2o panying the specification of U. S. application Serial No. 518,166 aforesaid, but, as hereinbeiore pointed out, the present invention in respect of the specific features thereof has wider application than that to which the arrangements shown in the aforesaid Figs. 8 and 9 are claimed in the earlier application just mentioned, and, of course, the claims of the present application are to be interpreted as excluding anything claimed in said earlier application.

For convenience also the reference numerals used in Figs. 8 and 9 of said earlier speciiication are used again in the accompanying drawings.

In the accompanying drawings, i, 2, t and il represent four consecutive rows of contra-rotational turbiue blading, two stages of each being carried on respective inner and outer rotor cylin.

ders and driving two stages I and II of an outer system of contra-rotational blading fragmentally shown, the foundation rings Ia and IIa being 4G essentially (as part of the present invention) of light alloy and having longitudinal dovetail or I equivalently shaped grooves receiving the correspondingly shaped roots of the blades I and E.

For a full description of the inner and outer `rotor cylinder members of the contra-rotational turbine reference should be had to the specification of the aforesaid U. S. application. The outer rotor cylinder comprises the shrouding rings 2d and td united 'by riveting, with a sleeve member 8, which, in the arrangement shown in Fig. i of the accompanying drawings, is provided with a cylindrical extension 8e which is riveted at 8f to the cylindrical sleeve member it to provide eiiible driving connection between the blade rows 55 2 and i of the inner system and the outer bing row whilstthe shroudlng ring Id of the i of the inner rotor cylinder comprising the contra-rotational stages i and 3 has riveted to it the internal flange of a corresponding cylindrical member 8c which is riveted at 9b to the flexible steel cylindrical member 9. The inner and outer rotor. cylinders `are carried by rotor discs and 6 respectively.

The cylindrical members 9 and IB are, in general, of substantially the same shape, the axially extending member 9 forming with the member sc a swan-neck device formed at its left-hand end with a radial flangedportion SI integral with winch is a re-entrant cylindrical flange 9m, thereby providing as shown the annular channel holding, by the radial rivets 971, the inserted exten. sion edge of the foundation ring Ia and also the extension of the blade root Ib which is xed in axial grooves in the light alloy ring Ia as shown in Figs. 3 and 4.

hn annular shield member is clamped through its cylindrical portion by the rivets 9b on the members 8c and 9 and` an annular deiiector member 2| is fixed by the rivets 8f to the members ile and l0.A There are also holes p as shown in the radial parts QZ o the channel members. These foundation rings Ia and Ila necessarily have cylindrical clearance from the outer parts of the cylindrical members '9 and I0. Thus, as shown by 'the short arrows 22 and 23, cooling air, due to pressure difference, flows back from the deector 2i to the axial grooves 24 in the foundation ring 12a, to and through the holes p and then through the grooves in the foundation ring la, along the similar space between the parts la and 9 as indicated by the arrow 23a, the shield 2t to be returnable to the annular stream of air or gas worked upon by the blading T. and 1I. The grooves 25 in the ring Ia are shown in Figs. 3 and 4, and it will be understood that the grooves 2li in the ring IIa are similar thereto but relatively reversed.`

At lila is shown a lipped flange on the member it co-operating with the left-hand end of the member 9 to form packing.

The arrangement shown in Fig. 2 of the accompanying drawings differs only in detail from the arrangement shown in Fig. 1. At 26 is shown in dotted lines the final blading stage of a turbine driving the compressor which supplies the combustion chamber exhausting into said turbine and thencey passing products into the turbine blading stages I to At 2l and 28 are fragmentarily shown labyrinth packing members separating the moving parts from the last stage 26 of the compressor turbine, as will be well understood by those skilled in the art. There are also shown in Fig. 2 ventilation holes Vi and V2 and the cylindrical extension V3 of the member 8c for preventing the light alloy" foundation rings of the 'outer blading system being subjected to too high temperatures. These ventilation holes permit huid circulation from the turbine inletlas 1. In apparatus of the character described comprising an outer blading system and an inner bladed system surrounded by said outer system, a foundation ring of light alloy for at least one row of blading of said outer system, a driving member of reentrant form -connected with at least one row of blading of said inner system, said driving member having, an outer flange and an axially extending reentrant flange to provide an annular channel into which said foundation ring extends, and .means attaching said ring in said channel.

2. In apparatus of the character described comprising an outer blading system and an inner bladed system surrounded by said outer system, a foundation ring of light alloy for at least one row of blading of said outer system, a driving member of reentrant form connected with at leastone row of blading of said inner system, said driving member having an outer flange and an axially extending reentrant flange to provide an annular channel into which said foundation ring extends, said row of blading of the outer sys.. tem also having blade roots extended axially beyond the blades and received in said annular channel, and means attaching said ring in said channel. i

3. In apparatus of the character described comprising an outer blading system and an inner bladed system surrounded by said outer system, a foundation ring of light alloy for at least one row of blading of said vouter system, a driving member of reentrant form connected with at least one row of blading of said inner system, said driving member having an outer fiange and an axially extending reentrant ange to provide an annular channel into which said foundation ring extends, and means attaching said ring in said channel, the inner surface of said foundation ring having a clearance from said driving member and said ring and member having a passage for the circulation of cooling fluid communicating with said clearance.

4. In apparatus of the character described comprising an outer blading system and an inner bladed system surrounded byA said outer system, a foundation ring of light alloy for at least one row of blading vof 4said outersystem, a driving member of reentrant form connected with at least one row of blading of said inner system, said driving member having an outer flange and an axially extending reentrant flange to provide an annular channel into which said foundation ring extends, means attaching said ring in said channel, and iud deflecting means carried by said member to deflect cooling fluid into said structure.

5. In apparatus oi' ,the character described.

an'axi'ally extending reentrant iiange to provide an annular channel into which said foundation ring extends, means attaching said ring in said channel, and heat shielding means carried by said driving member and interposed between said.

foundation ring and the blading of the inner system. o

KARL Baumann.

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