US2641439A - Cooled turbine or compressor blade - Google Patents

Description

June 9, 1953 s. B. WILLIAMS 2,641,439

June 9, 1953 s. B. WILLIAMS cooLED TURBINE 0R COMPRESSOR BLADE 3 Sheets-Sheet 2 Filed 0G12. 1, 1947 June 9, 1953 s. B. WILLIAMS cooLEn TURBINE 0R COMPRESSOR BLADE:

5 Sheets-Sheet 5 Filed 001,. 1, 194'? INVENTOR. Samye] MZL'ama BY FF/YEKS Patented June 9, 1953 UNITED PATENT QFFICE 'OL) *B OR CVPRSSOR L B. Williams, Deiroit, Mieli., assigner to Chrysler Corporation, Highland Park, Mich.; a corporation 'of Delaware Application (')toli 1, 1947-; Serial No; 7?753150 i2 Claims.

l This applicationrel'ate's to a structure passages therein. More specically, it relates t the production of an cbject, which maybe 'a tl`1`r= bine blade or ine like :having cooling passages 'formed therein.

Arifobject of the present invention is to 'pro' vide fr the production f an article having a pllll'ialit'y` o f `passages' therein, which may be 'small 'iii S`iz'e l ar`1d relatively 4close to the Surface fr the' sake of cooling thearticle.

Cth'er 'objects Will appear from the disclosure. In the drawings: I ynig. 1 is a plan view or a blank of 'which a tuibino blade is to be refined:

Fig. 2 is a setl View taken alofl'g the li'r 1 `zv2 of Fig'. 1;

Figs. 3, 4, and 5 are sectional views similar to Fig. "2 showing ino blank after' successive steps have been formed upon it; nig. 6 'is a sectional View taken along 'the line 6-6 of Fig., 1;

Figs. "ia-nd 8 are seotionalvviews talgenalong the lines '1 1 and en -'s after the steps'illustiatod in 'Figa 3, 4, and 5 have been performed 'upon Athe blank; f tige a view of a completed blade -foirled yfrom the blank; and

liigs. 1 and are -sectiolrialnviewstakeh along the y'lines -Iil--Ill and H1-II of Fig. 9

Fig. 1 snows a lblank lg from which ya turbina 'blade is to be 'fomjed frne blank lo has -agnxgt Aportion II through which an opening I2 is lformed. 4'leyond the outer end of the open-ing I2 in the blade portion proper o f the Ablank I U, there is 4formed in the surface of the blank aplurality of ridges I3 between which are formed grooves I4. Most of the grooves and ridges curve near their outer en ds and terminate in the financi-one edge of the blank I0'. lCertain ridges t3 terminating in the tip vof theblank .grow noticeably wider Iat the tip of the blank andthereby im crease the spacing of the grooves lvI4 formed 'between them. The 4blank I' is approximately uniform in width throughout the :greater part `of the lblade portion vproper and commen-ces tod-imnish in Width at a region near the :root II. Just before the blank commences to 'diminish in Widthy alternate ridges I3 terminate; nearer the root `I I, alternate ones 'of the remaining ridges terminate; and vfinally three ridges runas =far as the vouter "end 'of the opening I2, where 'they terminate and their upper surfaces merge with the 'surface of the blank `as indicated at I5 in Figs. l and b1li-. As indicated -in Fig. 1l, the grooves vI4 are yrelatively shallow throughout the having 2 part Aof the blade portion proper that is of lurl-ivform width and then increase in depth `at 'the region Where the yblank commences to .narrow and merge smoothly at their bottoms IWith the bottom of the opening I2.

The `blank I0 With its passage I2, ridges I3., and grooves I4 may be formed of Stellite lby precision casting. Thereupon the grooves "I4 are lled with a suitable -lling material such as aluminum, cadmium, Yor a graphiteeccntaining wax. The filling material is indicated 'by the reference character I6. Thereupon one side iof the blank I0,- which may predominantly be 'cobalt is plated with a suitable `metal suchlas nickel by a process such as '-electrodeposition. The plating, which is indicated 'by reference charac ter Il, .extends over the surface -15 adjacent `the root I I 'and over the ridges I3 andthe 'llingma terial I in the grooves I4. Then a coating or plating I8, which may be chromium, lis 'applied to the nickel coating Il, for example, by the process of electrodepositon. Next the Illing -'material I6 is 'removed through the passages 19 fiormed bythe grooves I3 and 'thepl'atings I'l and I8. vWhen the filling material is aluminum, it may -b'e removed by' caustic soda. When vthe' 'lli "ing material is cadmium, it may be removed` y heating to vaporization. When the filling nii'ae y'i'.er-al -i 'a graphite-containing Wax, Ait inyibe 'frelnflca'ved by melting. Finally 'the bond between the plating and blank l0 may be strengthened 7lby appropriate Lheat treating to make *the nickel plating lalloy with the chromium plating and with the cobalt blank I0.

As seen in Figs. 9, `1(),^and '1l'1,'the turbine blade fo'r'med by the yprocess just described, hasl ashelftlike portion '|99a projecting from the concav'eis'ide 4of the blade. This vportion serves to space the blade from an adjacent blade, which is not 'lsho'vv'h. Reinforcing ribs 'or flanges i20, 32|, fanti '22 de'pend `-ifrf` rr1-fthe shelf-"like portions 19a.

yIn 'operation the vb l'adewill be -rotated while be ing attached "through the root 'portion 'I I, 'which is radially innermost. Air :will flow through :cenltrifugal action V orb'y reasonof 'anfavailabl'e presv Vsore dinerentialr'adially outwardly, or yupwardly 'as seenin Figfl, ythrough the blade. lThe 'a''r enter-s the opening -I 2 'and :continues on through the passages I9 "ii'n'ally escaping l'rom the blade at one ledge and at the tip. vThe`1`9ll`l20-Sefof fthe air passing through the bladeiisto'eoolthe ibl'ade. The cooling .is yeffective Abecause 'the pa'ssa'gesiar'e shallow throughout most o'fthe 1en`gthen'ed=blade allowing zhigh ow velocities `v'vith acomp'ar'ati'vely smallfamount-of coolant now-ing,

The above described process for forming the passages I9 and blade make it possible for the passages to be relatively shallow.

I claim:

1. A blade comprising a cast metal member having a plurality of ridges and grooves between the ridges and electrolytically deposited plating metal covering and alloyed with the ridges. and bridging the grooves so as to cooperate with the grooves to form cooling passages adjacent one surface of the blade, said blade having a hub portion provided with an opening with Vwhich said grooves and passages establish communication, said grooves corresponding in num'berto said passages and including at least first;'seco'nd`,' and third sets of grooves in series by sets in that order leading toward the hub opening, saidsecond set of grooves being fewer in number than said rst set and said third set being--fewer'in number than said second set, said first set of grooves combining at least by twos to'formzthe grooves of said second set and said second set of grooves combining at least ,by twos to form the grooves of said third set.

2. A blade comprising a cast metal member having a hub portion provided with an opening and a blade portion having a plurality of ridges on one side and grooves between them communieating with thehub opening, some of vthe ridges vextending to the hub portion, and plating metal covering the ridges` and bridging the grooves so as to cooperate with the grooves to form cooling passagescommunicating with the hub opening.`

3. A blade comprising a cast metal member having av hub portion provided with an opening and a'bladeportion having a plurality -ofcurved ridges on' one side deflningegrooves and terminating in the blade ,tip and aside edge and communicating with the'hub opening, some of the ridges extending tothe hub portion, other ridges terminating in spaced relation to the hub portion, still Vother ridges terminating in more ,greatly spaced relation to the hub portion, the grooves decreasing in vdepth from the hub portion .tothe tip, and plating metal covering the ridges and bridging the grooves so as to' combine withxthe grooves to form v`cooling passages" adjacent one side ofthe blade.l j 4 g' e fl.4 The blade specified inclairn 3,1m@ cast metal member being of Stellite, and the plating metal .being niekel-y f .5.' `The Yblade Speeedinelaimg@ .the pas? metal .member beine .0f Stellite., andthe plei'neymetal being nickel, the blade further includinga a coatme ef chromium 01,1 the, niekeL j. A lstructure comprisingA a metallicpartj, having an opening in one end and an external surface provided withrridges andrgroovesbetween the Mr ilvihges',andy a metallic electro-plating covering the ridges and bridging the grooves to cooperate with the grooves to4 form vpassagescorresponding in number to thevnumber of grooves, vsaid plurality of/grooves establishing communication .with said opening and including at least first,` second and third sets of grooves in series by sets in that order leading vtoward. said opening, said second set of grooves being of .afewer number thanthe first set, and said third set of grooves l.being ofa fewer number than the secondset, said-firstfset of grooves-combining at least by twos to formthe 'grooves of said second set and said second set of grooves combining atleast by twos traversed internally by? awplurality of 'streams 'of the same fluid, said turbine blade having a hollow, open-ended root and a blade part proper connected to the root and having a tip edge and two side edges, and a series-connected progression of rst, second, and third groups of internal passages in said blade extending in that order from perforations formed in at least one said edge yof the blade part proper to the'hollow interior of the root, said rst group of passages combining at least by twos to form said second group of passages and said second group of passages combining atleast by twos to form said third group of passages.

v8. A blade according to claim 7, in which the tip edge and oneside edge contain all the perfor- .ations aforesaid and in which the aggregate number of perforations corresponds to the number of passages in said rst group.

Ina,4 turbine blade proper having concave and convex faces and consisting longways of a rootportion, a neck .portion and .a blade portion having va tip edge, a relatively sharp side ,edge and a relatively round side edge; amotivefluid conductingsurfacemeans, said motive fluidconducting surface means being in ,thefoimpfa shelf axedalong the neck-blade boundary.v and projecting normalwise from the concave face, said motive fiuid conducting ,surface meansgb'ein'g adaptedto provide on-eside of agas-flow channel, and a coolant gas conductingsurface means, said coolant gas conducting surface means. internally traversing saidblade proper longways and 'denning cooling passages establishing communication between said portions, said passages emergingat an` angleto said blade proper longways, fromthe blade portion in openings along said sharpedge and said tip edge.

, 10. A rooted turbine blade vgradually vwidening from the root thereof. and having r angopen mouth atthe meterla ablede Section. Proper provided with a tip edge and side edges, a throat connecting the blade section proper to `the root, and means f orrnrlg @progression offirst, second, and third Igroups ofcooling poresleading in vthat order from a tip and side edge toward the open' mouth of the bladeL/said secondv group of pores being fewer in number thansaidirstfgroup and seid third. group.. ef. leeres beine fewer hinunter than said second group, said firstgroup offpores combining atv leastrby twos to,V form saids 'cond group, lsaid second group ofpores combiningA at least by twos to forrn'said third group.

" 11. A rooted turbine' blade f `radi'lally widening 'If-I 'omv theiroot thereof and having an open mouth atl the' root enoLa bladesection proper provided with a tipedge and side v ed'ges`,a throat connecting the blade section proper towthe root, and

means forming alprogre'ssio'n of first, second, and third groups of cooling pores leading vin that order from at least the tipedge toward the openmouth ofthe blaue,` said second group` @spores `being fewer in'number than said rst group and said third g'rouprof pores being fewer in numberthan said second group, .said first group of pores com'- bining at least by twosto'"formsaidsecondgroup, salid's'econd group of pores combining atleast by twosto form said third group. .f

12. 'A' rooted turbine blade having an open mouth'at 'the root end', a blade section properpro'- vided with a tip edge and side edges, a' throat connecting the blade section proper to` theroot, and' meansforming a'progres'sion of at 'least'first second, Yand third sets of cooling pores leading in that orderfrom-s'paced orifices inthe 'tipfedge toward thev open mouth ofthe bla`de'said first-set of pores'being 'equalin'number to saidoriicesfand combining at least by twos to form said second set of pores and said second sei'I combining at least by twos to form said third set.

SAMUEL B. WILLIAMS.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date Siegel Feb. 4, 1919 Rosenqvisi*I Aug. 6, 1929 Reuss Mar. 17, 1936 Meyer Nov. 5, 1940 Zellbeck Sept. 29, 1942 Nachtman June 25, 1946 FOREIGN PATENTS Number Country Date 319,622 Great Britain Dec. 18, 1930 594,931 Germany Mar. 23, 1934 5 878,999 France Nov` 2, 1942 OTHER REFERENCES Haekhs Chemical Dictionary, 2nd Edition, Blakistons Son and Co., Philadelphia, 1937, `page 10 885.

Platingy January 1948, page 46.

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