To reduce a leakage amount of working f luid f lowing f rom a
high-pre s sure s ide to a low-pres sure s ide, a shaf t sea l ing appa ra tus i s
ins ta l led around a rotor in a rotat ing machine such as a ga s turbine or a
s team turbine. As an example of the shaf t seal ing appa ratus , for
example, the shaf t seal ing appa ra tus di sclosed in Pat ent Document 1
below i s known.
[0003]
Such a shaf t sea l ing apparatus i s equipped wi th a hous ing
ins ta l led on a s tator , and a seal body made up of numerous thin seal
pieces .
The sea l body i s conf igured so tha t the numerous thin s eal pi eces
are mutual ly s tacked wi th microgaps wi th a thicknes s di rec t ion of each
thin sea l piece di rected in a ci rcumf erent ial di rect ion of a rotor .
Eve ry thin sea l pie ce is s lant ingly di sposed so tha t a radi al inne r end
( f ront end) thereof i s located at a pos i t ion clos er to a rotat ing-di rec t ion
f ront s ide of the rotor than a radial out er end ( rea r end) thereof . The
3
thin seal piece s are conf igured so that the rea r ends the reof are
connected to one anothe r , and so that the f ront ends the reof a re f ree
ends .
[0004]
In the shaf t seal ing appa ra tus schemat ical ly conf igured in thi s
way, when the rotor s tands s t i l l , the f ront end of each thin seal piece i s
in contac t wi th the rotor . In cont ras t , when the rotor rota tes , the f ront
end of each thin sea l piece i s rai sed f rom an oute r ci rcumfe rence of the
rotor and comes out of contac t wi th the rotor due to a dynamic pres sure
ef f ect caused by the rota t ion of the rotor . For thi s reason, in the shaf t
seal ing appa ratus , the wea r of each thin s eal piece i s suppre s sed, and a
seal se rvic e t ime i s inc reased.
[0005]
FIG. 11 i s a schemat ic conf igurat ion view of a convent ional
shaf t seal ing appa ratus 110. The shaf t seal ing appa ratus 110 i s
conf igured so tha t a plural i ty of se al segment s 111 ext ending in a
ci rcular arc shape are disposed in a tor ic hous ing 9 suppor ted on an
inner ci rcumf erent i al sur face of a s ta tor .
[0006]
The seal segment 111 i s made up of a se al body 112 compos ed of
numerous thin seal pieces 120, holding r ings 113 and 114 having a
U- shaped c ros s se ct ion and holding the nume rous thin seal pieces 120,
and high- pres sure s ide late ral pla te 116 and low-pres sure s ide la te ral
pla te 117 ins tal led wi th the sea l body 112 inte rposed therebetween in
an axial di rect ion of the rotor .
[0007]
The holding r ings 113 and 114 a re membe r s for holding head
par t s 121 of the numerous thin seal pieces 120. Fur the r , rotor radial
outer ends of the high- pre s sure s ide latera l pla te 116 and low-pres sure
4
s ide lateral pla te 117 a re formed wi th prot rus ion pa r t s 116a and 117a
di rec ted in the axial di rect ion. The prot rus ion pa r t s 116a and 117a a re
held so as to be prevented f rom fal l ing of f in a radial di rect ion by the
holding r ings 113 and 114 in a s tate in whi ch they a re inse r ted into
dents 123 between the head pa r t s 121 and body par t s 122 of the thin
seal pieces 120.
[Related Ar t Document s ]
[Patent Document s ]
[0008]
[Patent Document 1] Japanese Patent No. 3616016
[Di sclosure of the Invent ion]
[Problems to be Solved by the Invent ion]
[0009]
Incidental ly, the shaf t sea l ing appar atus 110 of the above
conf igura t ion i s conf igured so that the holding r ings 113 and 114
cons t i tut ing the s ea l segment 111 hold the high- pre s sure s ide late ral
pla te 116 and low-pres sure s ide late ral plate 117. Due to the exi s tence
of the holding r ings 113 and 114, the shaf t seal ing apparatus 110 has a
rotor radial length of , for ins tance, 30 to 40 mm and a width of , for
ins tance, 15 mm, and thus i s voluminous . As a re sul t , due to the
res t r ic t ion of a mount ing space, appl ica t ion f ie lds are l imi t ed.
[0010]
The present invent ion has been made in cons iderat ion of the se
ci rcums tance s , and an obj ect of the pr esent invent ion i s to provide a
shaf t seal ing appa ra tus that is made smal le r to al low appl i cat ion f ie lds
to be widened, and a rotat ing machine equipped wi th the s ame.
[Means for Solving the Problems ]
[0011]
To ac compl i sh the above obj ect , the pre sent invent ion provide s
5
the fol lowing means .
According to a f i r s t aspect of the present invent ion, there i s
provided a shaf t sea l ing appa ratus that i s ins ta l led in an annular space
between a rotor and a s tator sur rounding an oute r ci rcumf erent ial s ide
of the rotor and tha t divides the annular space into a low-pre s sure s ide
region and a high-pres sure s ide region in an axial di rect ion of the rotor ,
and tha t inc ludes a s eal body formed by s tacking a plural i ty of thin seal
pieces , which extend f rom the s tator towa rd a radial inne r s ide of the
rotor , in a ci rcumf erent ial di rect ion of the rotor , and la tera l plates
having a sur f ace facing the axia l di rec t ion and curved and extending in
a ci rcumfe rent ia l di rect ion of the annula r space. The s eal body i s
welded to the sur f aces of the late ra l plates which face the axial
di rec t ion so that the seal body fol lows a curved shape of the late ral
pla tes .
[0012]
According to the above conf igurat ion, the latera l pla tes a re
welded to the seal body. Thereby, the member for holding the late ra l
pla tes together wi th the thin seal piec e can be omi t ted. Thi s a l lows
the shaf t seal ing apparatus to be made sma l le r .
[0013]
Fur the r , according to a second aspec t of the pres ent invent ion, i t
i s prefe rable that in the shaf t sea l ing appara tus , the late ral plate s a re
made up of a high-pre s sure s ide late ral pla te di sposed so a s to fol low a
high-pre s sure s ide of the seal body and a low-pres sure s ide late ral plate
di sposed so as to fol low a low-pres sure s ide of the seal body, and the
seal body is we lded to the sur f aces of the high-pres sure s ide late ral
pla te and low-pres sure s ide la teral pla te which face the axi al di rect ion.
[0014]
Fur the r , according to a thi rd aspect of the present invent ion, i t i s
6
prefe rable that the shaf t seal ing apparatus f ur the r inc lude s a protect ion
pla te having a sur f ace facing the radia l di rect ion of the rotor and
curved and extending in the ci rcumfe rent ial di rect ion of the annular
space. The protect ion plate may be welded to a radial out e r end of the
seal body.
[0015]
According to the conf igura t ion, a prote ct ing funct ion of the shaf t
seal ing appa ra tus can be fur ther improved. Fur the r , s ince the
exposure of the seal body i s reduced, the handl ing of the seal segment
i s made eas i er . Fur thermore, by welding the protect ion plat e, a
connect ion between the plural i ty of thin s ea l piece s cons t i tut ing the
seal body can be fur the r reinforc ed.
[0016]
Fur the r , according to a four th aspect of the present invent ion, i t
i s pref erable that in the shaf t seal ing apparatus , the high-pre s sure s ide
late ral pla te i s formed wi th an ela s t ic element pre s sur izing a par t of the
high-pre s sure s ide late ral plate f rom the high-pre s sure s ide region
towa rd the low-pres sure s ide region.
[0017]
According to the conf igurat ion, the el as t ic element pres sur ize s
the high-pres sure s ide late ra l plate f rom the high-pre s sure s ide to the
low-pres sure s ide. The reby, the high-pres sure s ide late ral pla te i s
al lowed to re l iably fol low the thin se al piece, and vibrat ion of the
high-pre s sure s ide l ateral plate can be suppre s sed. In othe r words , the
elas t ic element cons tant ly appl ie s pres sure to the high-pres sure s ide
late ral plate 16F. The reby, an operat ion of the shaf t seal ing appa ratus
can be s tabi l i zed.
[0018]
Fur the r, according to a f i f th aspect of the present invent ion,
7
the re i s provided a rota t ing machine equipped wi th the shaf t seal ing
apparatus .
[Ef fect s of the Invent ion]
[0019]
According to the above-ment ioned sha f t seal ing appa ratus , the
late ral plates are welded to the seal body. Thereby, the member for
holding the la teral plates toge the r wi th the thin sea l pi ece can be
omi t ted. Thi s al lows the shaf t seal ing apparatus to be made sma l le r .
[Br ief De scr ipt ion of the Drawings ]
[0020]
FIG. 1 is a schemat ic ent i re conf igur at ion view of a gas turbine
( rota t ing machine ) according to a f i r s t embodiment of the present
invent ion.
FIG. 2 i s a cros s - s ect iona l view taken along the l ine S1-S1 in
FIG. 1.
FIG. 3 i s a c ros s - sect ional view that shows a shaf t se al ing
apparatus according to the f i r s t embodiment of the pre sent invent ion
and i s taken along the l ine S2-S2 in FIG. 2.
FIG. 4 i s a cros s -s ect iona l view of the shaf t seal ing apparatus
according to the f i r s t embodiment of the present invent ion f rom one
s ide to the othe r s ide in an axial di rec t ion.
FIG. 5 i s a c ros s - sect ional view that shows a shaf t se al ing
apparatus according to a second embodiment of the present invent ion
and i s taken along the l ine S2-S2 in FIG. 2.
FIG. 6 i s a c ros s - sect ional view that shows a shaf t se al ing
apparatus according to a modi f ied example of the second embodiment
of the present invent ion and i s taken along the l ine S2-S2 in FIG. 2.
FIG. 7 i s a c ros s - sect ional view that shows a shaf t se al ing
apparatus according to a thi rd embodiment of the present invent ion and
8
i s taken along the l ine S2-S2 in FIG. 2.
FIG. 8 i s a c ros s - sect ional view that shows a shaf t se al ing
apparatus according to a modi f ied example of the thi rd embodiment of
the present invent ion and is taken along the l ine S2-S2 in FIG. 2.
FIG. 9 i s a c ros s - sect ional view that shows a shaf t se al ing
apparatus according to a four th embodiment of the present invent ion
and i s taken along the l ine S2-S2 in FIG. 2.
FIG. 10 i s a cros s - sect ional view tha t shows a shaf t se al ing
apparatus according to a modi f icat ion of the four th embodiment of the
present invent ion and i s taken a long the l ine S2-S2 in FIG. 2.
FIG. 11 i s a cros s - s ect iona l view of a convent ional shaf t s e al ing
apparatus .
[Modes for Ca r rying out the Invent ion]
[0021]
(Fi r s t Embodiment )
He reinaf t er, a rota t ing machine according to a f i r s t embodiment
of the present invent ion wi l l be des cr ibed wi th ref erence to the
drawings .
FIG. 1 is a schemat ic ent i re conf igur at ion view of a gas turbine
( rota t ing machine ) 1 according to a f i r s t embodiment of the pre sent
invent ion.
As shown in FIG. 1, the gas turbine 1 inc lude s a compres sor
( rota t ing machine) 2 which int roduces and compres se s a great amount
of ai r the re into, a combus tor 3 which mixe s fue l into the compre s sed ai r
compres sed by the compres sor 2 and burns , and a gas turbine ( rotat ing
machine ) 4 which conve r t s the rmal ene rgy of the combus t ion gas
int roduced f rom the combus tor 3 into rotat ional ene rgy.
[0022]
The compres sor 2 and the turbine 4 include rotor s 2A and 4A
9
connected so as to be rotated togethe r , and s tator s 2B and 4B
sur rounding oute r ci rcumfe rence s ide s of the rotors 2A and 4A,
respect ively. Note that , in the fol lowing de scr ipt ion, unle s s
spec i f ical ly def ined othe rwi se, di rec t ions along the axi s O of the rotor s
2A and 4A are s imply refe r red to as an “axi s O di rect ion, ”
ci rcumfe rent ial di rect ions of the rotors 2A and 4A as a “ci r cumfe rent ial
di rec t ion, ” and radi al di rect ions of the rotor s 2A and 4A as a “radia l
di rec t ion. ” Fur the r , in the axi s O di rect ion of the rotor s 2A and 4A, a
high-pre s sure s ide i s refe r red to as a “one s ide, ” and a low-pres sure
s ide as an “other s ide. ”
[0023]
The rotors 2A and 4A have rota t ing shaf t s 6c and 6, and a
plural i ty of annular rotor blade groups 7c and 7 f ixed spaced apar t f rom
each othe r in the axi s O di rect ion. Each of the annula r rotor blade
groups 7c and 7 is conf igured to have a plural i ty of rotor bl ades , which
are f ixed to an outer ci rcumfe rence of each of the rota t ing shaf ts 6c and
6 and which a re spaced apa r t f rom ea ch other in the ci r cumfe rent ial
di rec t ion.
[0024]
The s tator s 2B and 4B inc lude cas ings 2b and 4b, and a plural i ty
of annula r s tator vane groups 5c and 5, which are f ixed in the cas ings
2b and 4b and whi ch are spaced apar t f rom each othe r in the axi s O
di rec t ion.
Each of the annula r s ta tor vane groups 5c and 5 has a plura l i ty of
s ta tor vane, which i s f ixed to an inner sur f ace of each of the cas ings 2b
and 4b and which a re spaced apar t f rom each other in the
ci rcumfe rent ial di rect ion. A f ront end of each s tator vane i s formed
wi th a hub shroud. The hub shrouds (s ta tor s ) are connected in the
ci rcumfe rent ial di re ct ion, and sur round the outer c i rcumfe rences of the
10
rotat ing shaf t s 6c and 6 in a tor ic shape as a whole.
The s tator blade s of the annula r s tator vane groups 5c and 5 are
di sposed a l te rnate ly wi th the rotor vanes of the plural i ty of annular
rotor blade groups 7c and 7 in the axis O di rect ion.
[0025]
In the compres sor 2 and the turbine 4, to prevent a working f luid
(compres sed ai r or combus t ion ga s ) g f rom leaking out f rom the
high-pre s sure s ide to the low-pres sure s ide in the axi s O di rec t ion, as
shown in FIG. 1, the shaf t seal ing appa ratuses 10c and 10 are ins tal led
on the hub shrouds of the re spect ive annula r s tator vane groups 5c and
5. Fur the r , the sha f t seal ing appa ra tus es 10c and 10 are a l so ins tal led
on bea r ing pa r t s (s tator s ) 2c and 4c on which the cas ings 2b and 4b
suppor t the rotat ing shaf t s 6c and 6 in orde r to prevent the working
f luid g f rom leaking out f rom the high-pre s sure s ide to the low-pres sure
s ide.
[0026]
He reinaf t er , an embodiment of the shaf t seal ing appa ra tus 10 of
the turbine 4 wi l l be de sc r ibed. Al though the fol lowing descr ipt ion
wi l l be given of the shaf t seal ing apparatus 10 of the turbine 4, the
shaf t sea l ing appa ra tus 10c of the compre s sor 2 bas ical ly has a s imi la r
conf igura t ion, and a desc r ipt ion the reof wi l l be omi t ted he re.
[0027]
FIG. 2 i s a cros s -s ect iona l view taken along the l ine S1-S1 in
FIG. 1, and FIG. 3 i s a cros s - sect ional view taken along the l ine S2-S2
in FIG. 2.
As shown in FIG. 2, the shaf t sea l ing apparatus 10 of the turbine
4 i s conf igured so that a plural i ty of s eal segment s 11 ( in the pre sent
embodiment , e ight s eal segment s ) extending in an ci rcular a rc shape a re
di sposed in a hous ing 9, which i s an annular space suppor ted on each of
11
the hub shroud of the annula r s tator vane group 5 and an inner
ci rcumfe rent ial sur f ace of the bear ing par t 4c, in the ci rcumfe rent ial
di rec t ion. The sea l segment s 11 are s egmented so as to be di rec ted
towa rd a rotat ing-di rect ion f ront s ide as they are di rected f rom a radial
outer s ide towa rd a radia l inne r s ide.
[0028]
The hous ing 9 ext ends along the out er ci rcumf erence of the
rotat ing shaf t 6 throughout the ci rcumference, and i s provided wi th a
tor ic receiving spac e 9a. As shown in FIG. 3, the rec eiving space 9a
of the hous ing 9 is conf igured so that a por t ion of an opening s ide, i .e. ,
a radial inner s ide, the reof i s conf igur ed to be an inner spa ce 9b whose
width dimens ion (dimens ion of the axis O di rec t ion) i s formed so as to
be smal l . Fur the r , a space spaced apar t f rom an opening of the
rece iving space 9a to the radial outer s ide, i . e. , a space of the radial
outer s ide far the r than the inner space 9b, is conf igured to be an oute r
space 9c whose width dimens ion i s f ormed so as to be large. The inne r
space 9b and the outer space 9c are in communica t ion wi th each othe r .
Thus , the opening pa r t 9d of the inner space 9b i s di re cted to the
rotat ing shaf t 6 of the radi al inner s ide.
[0029]
As shown in FIG. 3, each seal segment 11 i s made up of a seal
body 12 composed of a number of thin seal pi eces 20 (see FIG. 4) , an
elas t ic body 15 urging the seal body 12 toward the radia l inne r s ide,
and high- pres sure s ide late ra l plate 16 and low-pres sure s ide la te ral
pla te 17 ins ta l led wi th the se al body 12 interposed the rebe tween in the
axi s O di rect ion.
[0030]
FIG. 4 i s a schema t ic view of the seal s egment 11 viewed f rom a
one s ide to an other s ide in the axis O di rec t ion.
12
As shown in FIG. 4, the seal body 12 i s conf igured so that
shee t -shaped thin s eal pieces 20 are nume rous ly s tacked ( see FIG. 2) ,
and so tha t radial outer ends of the numerous thin seal pi eces 20, i .e. ,
rea r ends 20a of the thin seal pieces 20, are connec ted to one another .
As shown in FIG. 2, the numerous thin seal piece s 20 are ar ranged so as
to be di rec ted to the rotat ing-di rec t ion f ront s ide as they are di rected
f rom the radial oute r s ide towa rd the radia l inner s ide.
[0031]
Fur the r , the thin seal piece 20 i s a membe r that i s mainly formed
of a thin s teel she et , i s formed in a T shape when viewed f rom the
ci rcumfe rent ial di rect ion of the rotat ing shaf t 6 as shown in FIG. 3, and
i s di sposed so that a width di rect ion thereof i s di rected in the axi s O
di rec t ion of the rota t ing shaf t 6. In other words , the thin seal pie ce 20
i s di sposed so tha t a thickne s s di rect ion the reof i s di re cted in the
ci rcumfe rent ial di re ct ion of the rota t ing shaf t 6.
[0032]
The thin seal piece 20 ha s a head par t 21 and a body par t 22
whose width and thicknes s dimens ions are formed so as to be smal ler
than thos e of the he ad pa r t 21. The thin seal piece 20 i s formed f rom
the radia l outer s ide towa rd the radia l inne r s ide of the rot at ing shaf t 6
so as to cont inue in the order of the head pa r t 21 and the body pa r t 22.
[0033]
The nume rous thin seal pieces 20 are connected to each othe r in
such a manne r that the head pa r t s 21 the reof are welded to one anothe r .
Fur the r , the body pa r t s 22 of the numerous thin sea l pieces 20 a re
al lowed to unde rgo elas t ic def ormat ion. Radial inne r ends of the body
par t s 22, i . e. , f ront ends 20b of the thin seal pieces 20, become f ree
ends . Thus , dur ing a shutdown pe r iod of the rota t ing shaf t 6, a s ide of
the f ront end 20b of each thin seal piec e 20 i s conf igured so as to be in
13
contact wi th the rot at ing shaf t 6 unde r a prede termined pre -pres sure.
[0034]
As shown in FIG. 4, the nume rous thin seal piece s 20 are
ar ranged in the ci rcumf erent ial di rec t ion wi th microgaps s
the rebetween. By making a thicknes s dimens ion of the head pa r t 21
large r than that of the body par t 22, the nume rous thin sea l piece s 20
form the mic rogaps s between the body pa r t s 22 of the two thin seal
pieces 20 that a re adjacent to each othe r in the thicknes s di rec t ion
the reof .
[0035]
Al l of the high- pres sure s ide late ral plate 16 and the
low-pres sure s ide l ateral pla te 17 a re conf igured so tha t the thicknes s
di rec t ion the reof i s di rec ted in the axi s O di rec t ion, and so that a shape
the reof which i s viewed f rom the axi s O di rec t ion of the rotat ing shaf t 6
i s a ci rcula r a rc band shape. Tha t i s , the high-pres sure s ide late ra l
pla te 16 and the low-pres sure s ide late ra l plate 17 have a sur f ace facing
the axi s O di rect ion, and a re formed so as to be curved and extend in a
ci rcumfe rent ial di re ct ion of the receiving spa ce 9a. Fur the r , a radial
dimens ion of the low-pre s sure s ide l ate ral plate 17 i s set to be shor ter
than that of the high-pres sure s ide late ral plate 16.
[0036]
Al l of the high- pres sure s ide late ral plate 16 and the
low-pres sure s ide latera l plate 17 are welded to the se al body 12 at the
weld zone W of the radia l oute r end thereof . The high-pr es sure s ide
late ral plate 16 and the low-pres sure s ide late ral plate 17 a re welded to
the seal body 12 along the ci rcumfe rent i al di rect ion, and the weld zone s
W are al so curved and extend in the ci rcumfe rent ia l di rec t ion.
The reby, the pl ate sur face of the high-pres sure s ide late ral plat e 16
which faces the low-pres sure s ide of the high-pres sure s ide l ateral plate
14
16 i s f ixed so a s to cove r the high-pres sure s ide of the seal body 12, and
the plate sur face of the low-pre s sure s ide late ra l plate 17 which f aces
the high-pres sure s ide of the low-pres sure s ide la te ral plat e 17 i s f ixe d
so as to cover the low-pre s sure s ide of the seal body 12.
[0037]
As a welding method used for thi s welding, for example, lase r
welding, TIG welding, and so on. may be appl ied. Howeve r , the
welding method i s not l imi ted thereto.
Fur the r , in the event of the welding, to make the qual i ty of the
welding good, later al sur face s of the seal body 12 may be pol i shed,
the reby removing i r regula r i ty theref rom.
Fur the r , i t i s pre ferable that the welding i s cont inuous ly
per formed in the ci rcumfe rent ial di re ct ion. Howeve r , i f there i s a
conce rn of warpage of the thin seal pi ece 20 caused by the we lding,
spot welding may be per formed at predetermined inte rval s .
[0038]
In the pre sent embodiment , the radia l inne r end of the
high-pre s sure s ide late ral pla te 16, i . e. , the f ront end of the
high-pre s sure s ide late ral plate 16, extends up to the opening of the
radia l inne r s ide of the receiving space 9a. The reby, the f ront end 20b
of the thin sea l pi ece 20 extending out f rom the receiving space 9a
towa rd the radia l inner s ide extends out to the r adial inne r s ide f ar ther
than the f ront end of the high-pre s sure s ide late ra l plate 16.
Fur the r , in the pre s ent embodiment , the radial inne r end of the
low-pres sure s ide lateral plate 17, i . e. , the f ront end of the
low-pres sure s ide lateral plate 17, is located f ar the r towa rd the radial
outer s ide than the opening of the radial inne r s ide of the receiving
space 9a.
[0039]
15
As shown in FIG. 3, the sea l segment 11 i s housed in the
rece iving space 9a of the hous ing 9 wi th an al lowance.
In great er detai l , the head pa r t 21 of the thin seal piece 20 i s
housed in the outer space 9c of the re ceiving space 9a, and the highpres
sure s ide late ra l plate 16 and low-pres sure s ide la te ral plate 17 and
the body pa r t 22 of the thin seal pieces 20 a re housed in the inne r space
9b of the receiving space 9a. The f ront end of the body pa r t 22, i .e. ,
the f ront end 20b of the thin seal piece 20, prot rude s f rom the opening
of the rece iving space 9a toward the rot at ing shaf t 6.
[0040]
The seal segment 11 i s conf igured so that the head pa r t 21 of the
thin seal piece 20 inter fe re s wi th an inner wa l l of the out e r space 9c of
the hous ing 9 and i s l imi ted in radial di splacement , and so tha t the
high- pr es sure s ide lateral plate 16 and low-pres sure s ide later al plate
17 inte r f ere wi th an inne r wa l l of the inner space 9b of the hous ing 9
and ar e l imi ted in di splacement in the axi s O di rect ion wi thin a
prede termined range. Fur the r , the seal segment 11 i s bi ased toward
the radia l inne r s ide by the ela s t ic body 15 a r ranged in the outer space
9c.
[0041]
According to the above embodiment , the high- pres sure s ide
late ral plate 16 and low-pres sure s ide la teral pla te 17 are welded to the
seal body 12. The reby, a membe r for holding the high- pre s sure s ide
late ral plate 16 and low-pres sure s ide late ral plate 17 along wi th the
head par t 21 of the thin seal piece 20 c an be omi t ted. Thi s al lows the
shaf t seal ing appa ra tus 10 to be made smal le r .
Fur the r , to f ix the high-pre s sure s ide late ral plate 16 and
low-pres sure s ide la tera l plate 17 to the seal body 12, i t i s unneces sa ry
to form a groove in the thin seal piece 20 making up the se al body 12.
16
As such, the thin s eal piec e 20 can be made shor t , and the s eal ing
apparatus can be made sma l le r .
[0042]
When the thin seal piece 20 is made shor t , the sheet thicknes s of
the thin seal piece 20 i s prefe rable to be reduced to prevent r igidi ty of
the thin seal piece 20 f rom being exces s ive. In the case of the pre sent
embodiment , for example, i t i s prefe rable that the sheet thicknes s of
0.04 mm to 0.06 mm i s employed.
[0043]
(Second Embodiment )
He reinaf t er , a shaf t seal ing appa ra tus 10B according to a second
embodiment of the present invent ion wi l l be des cr ibed us ing FIG. 5.
In thi s embodiment , membe r s that a re the same as the member s used in
the above-ment ioned embodiment a re given the same numera l s , and a
desc r ipt ion thereof wi l l be omi t ted he re .
[0044]
A thin sea l piece 20B making up the shaf t seal ing appa ra tus 10B
of the pres ent embodiment i s di f f erent f rom the thin seal pi e ce 20 of the
f i r s t embodiment in terms of the shape of the head par t 21. The head
par t 21B of the thin seal piece 20B of the present embodiment prot rude s
only to the othe r s ide of the axi s O di rect ion. That i s , a lateral end
20c of the one s ide of the axial di rect ion of the thin seal pieces 20B has
a l inea r shape. Fur ther , a round hole 24 i s f ormed in the vic ini ty of a
radia l oute r end of the thin s eal piece 20B.
[0045]
According to the above -ment ioned embodiment , the head pa r t
21B i s shaped so a s to prot rude only to one s ide of the axi s O di rect ion.
The reby, s ince the width of the axi s O di re ct ion of the thin seal piece
20B i s na r row, the shaf t sea l ing appa ratus can be made sma l le r .
17
Fur the r , the round hole 24 i s formed in the thin seal piec e 20B.
The reby, when the thin seal piece 20B i s combined as a seal body 12B,
workabi l i ty, for ins t ance, dur ing t ranspor t , can be improved.
[0046]
In the present embodiment , as in a shaf t seal ing apparatus 10C
shown in FIG. 6, a high-pre s sure s ide la te ral plate 16C may be
conf igured to have a length up to the f ront end of the head pa r t of the
thin seal piece 20B, and a weld zone W may be set to two place s
cor responding to the length of the high-pres sure s ide later al plate 16C.
Wi th thi s conf igura t ion, the seal body 12 i s more wide ly cove red by the
high-pre s sure s ide l ateral plate 16C. As such, a protec t ing f unc t ion of
the shaf t seal ing apparatus can be fur ther improved. Fur the r , s ince the
exposure of the se al body 12B i s reduced, the handl ing of a seal
segment 11C i s made eas ier .
[0047]
(Thi rd Embodiment )
He reinaf t er , a shaf t seal ing appar atus 10D according to a thi rd
embodiment of the present invent ion wi l l be desc r ibed us ing FIG. 7.
In thi s embodiment , membe r s that a re the same as the member s used in
the above-ment ioned embodiment a re given the same numera l s , and a
desc r ipt ion thereof wi l l be omi t ted he re .
[0048]
In the shaf t seal ing apparatus 10D of the present embodiment , a
protect ion plate 25 i s welded on a radial oute r s ide of a se al body 12B
making up a seal segment 11D. The protect ion plate 25 i s pre s sed so
as to be curved cor responding to a radia l oute r sur face of the seal body
12B. The thickne s s of the protec t ion plate 25 may be se t to a range of ,
for ins tance, 0.5 mm to 1.0 mm.
[0049]
18
According to the above -ment ioned embodiment , a protect ing
func t ion of the sha f t seal ing appa ra tus 10D can be fur the r improved.
Fur the r , s inc e the exposure of the seal body 12B i s reduced, the
handl ing of the s eal segment 11D is made eas ie r . Fur thermore, by
welding the protect ion plate 25, a connect ion between a plural i ty of
thin seal pieces 20B cons t i tut ing the seal body 12B can be fur ther
reinf orced.
[0050]
As a modi f ied example of the pre sent embodiment , a s shown in
FIG. 8, a protect ion plate 25E may al so be shaped so as to cover the
other s ide of the axi s O di rec t ion of an upper por t ion of the seal body
12B. Wi th thi s conf igurat ion, the protect ing funct ion of the shaf t
seal ing appa ratus 10E can be fur ther improved.
[0051]
(Four th Embodiment )
He reinaf t er , a shaf t seal ing apparatus 10F according to a f our th
embodiment of the present invent ion wi l l be desc r ibed us ing FIG. 9.
In thi s embodiment , membe r s that a re the same as the member s used in
the above-ment ioned embodiment a re given the same numera l s , and a
desc r ipt ion thereof wi l l be omi t ted he re .
[0052]
In the shaf t sea l ing appa ra tus 10F of the pre sent embodiment , a
plural i ty of dimple s 26 are provided on a high-pres sure s ide lateral
pla te 16F making up a seal segment 11D (only one dimple i s shown in
FIG. 9) . The dimple s 26 a re provided so as to prot rude in a radial
di rec t ion in the vicini ty of a radial inner end of the high-pres sure s ide
late ral pla te 16F. In detai l , the dimpl es 26 are provided by pres s ing
the high-pres sure s ide late ra l plat e 16F, and are each conf igured so that
a cros s sec t ion the reof when viewed f rom a ci rcumfe rent ial di rect ion
19
has a convex shape at one s ide of the axi s O di rect ion. The plural i ty
of dimple s 26 a re provided in the ci rcumfe rent ia l di rec t ion at
prede termined inte rval s .
[0053]
The dimple 26 i s formed to such a height that the top of the
dimple 26 i s in cont act wi th an inne r sur face of an inner space 9b of a
rece iving space 9a, or there i s a s l ight gap between the top of the
dimple 26 and the inner sur face of the inne r space 9b. By providing
thi s shape, the dimple 26 ful f i l l s a func t ion as an ela s t ic element .
Tha t is , a place at which the dimple 26 of the high-pres sure s ide late ral
pla te 16F i s formed i s pres sur i zed f rom the one s ide (high-pres sure
s ide ) towa rd the other s ide ( low-pres sure s ide ) .
[0054]
According to the above-ment ioned embodiment , the dimples 26
pres sur ize the high-pre s sure s ide lateral pl ate 16F f rom the
high-pre s sure s ide to the low-pre s sure s ide. Thereby, the
high-pre s sure s ide late ral plate 16F i s al lowed to re l iably fol low the
thin sea l piece 20B, and vibrat ion of the high-pre s sure s ide l ateral pl ate
16F can be cont rol led. In other words , the dimples 26 cons tant ly
apply pres sure to the high-pre s sure s ide latera l plate 16F. The reby, an
ope ra t ion of the sha f t seal ing apparatus 10F can be s tabi l ized.
[0055]
As a modi f ied example of the pre sent embodiment , a s shown in
FIG. 10, a conf igur at ion in which a wavy plate 27 whose shape viewed
f rom the axi s O di rect ion ha s approximately the same shape a s a
high-pre s sure s ide lateral plate 16C i s ins ta l led on the one s ide
(high-pres sure s ide ) of the axi s O di re ct ion of the high-pr es sure s ide
late ral plate 16C may al so be employed. The wavy pl ate 27 i s a
shee t -shaped member that i s formed of , for ins tance, spr ing s te el and
20
tha t i s al terna tely bent to the one s ide of the axi s O di rect ion and to the
other s ide of the axi s O di rect ion, and i s at tached to the one s ide of the
axi s O di rect ion of the high-pres sure s ide lateral plate 16C.
[0056]
A dimens ion of the axi s O di rect ion of the wavy plate 27 is set to
such a dimens ion a s to br idge a gap between the high-pre s sure s ide
late ral plate 16C and an inne r sur face of the inne r space 9b.
Fur the r , the wavy pla te 27 i s f ixed to the high-pres sure s ide
late ral plate 16C by adhes ion.
[0057]
According to the above -ment ioned embodiment , the wavy plate
27 i s int erposed be tween the high-pres sure s ide lat eral pl ate 16C and
the inner sur face of the inne r space 9b of the receiving space 9a.
The reby, in addi t ion to the ef f ect s of the four th embodiment , the wavy
pla te can pres sur i ze the high-pres sure s ide lateral pla te 16C ove r an
ent i re sur f ace of the high-pres sure s ide late ral pla te 16C.
Accordingly, the high-pres sure s ide l ateral pla te 16C i s al lowed to
fol low the ent i re ar ea of the thin sea l pieces 20B.
[ Indus t r ia l Appl icabi l i ty]
[0058]
According to the above-ment ioned sha f t seal ing appa ratus , the
late ral plates are welded to the seal body. Thereby, the member for
holding the la teral plates toge the r wi th the thin sea l pi ece can be
omi t ted. Thi s al lows the shaf t seal ing apparatus to be made sma l le r .
[Desc r ipt ion of Ref erence Nume ra ls ]
[0059]
O…axi s
1…ga s turbine ( rota t ing machine )
2…compres sor ( rotat ing machine )
21
4…ga s turbine ( rota t ing machine )
2A, 4A…rotor
2B, 4B…s tator
9a…receiving space (annular space)
10…shaf t seal ing appa ra tus
11…seal segment
12…seal body
16…high-pre s sure s ide late ral plat e ( lat eral pla te)
17…low-pres sure s ide late ra l plate ( lat eral pla te )
20…thin se al piece
25…protect ion plat e
26…dimple (e las t ic element )
27…wavy plate (e las t i c element )
22
I /We claim:
[Claim 1]
A shaf t seal ing appa ratus that i s ins t al led in an annula r space
between a rotor and a s tator sur rounding an oute r ci rcumf erent ial s ide
of the rotor and that divides the annular spa ce into a low-pre s sure s ide
region and a high-pres sure s ide region in an axial di rect ion of the rotor ,
the shaf t seal ing apparatus compr i s ing:
a seal body formed by s tacking a plural i ty of thin seal piece s ,
which extend f rom the s ta tor toward a radia l inne r s ide of the rotor , in a
ci rcumfe rent ial di re ct ion of the rotor ; and
lateral pla tes having a sur face f ac ing the axial di rect ion and
curved and extending in a ci rcumf erent ial di re ct ion of the annular
space,
whe rein the seal body i s welded to the sur face s of the late ral plates
which face the axia l di rect ion so tha t the seal body fol lows a curved
shape of the la teral pla tes .
[Claim 2]
The shaf t sea l ing appa ratus according to claim 1, whe rein:
the late ra l plates are made up of a high-pres sure s ide later al plate
di sposed so as to fol low a high-pres sure s ide of the sea l body and a
low-pres sure s ide la tera l plate di sposed so as to fol low a low-pres sure
s ide of the sea l body; and
the seal body i s we lded to the sur faces of the high-pres sure s ide
late ral plate and low-pre s sure s ide la teral plat e which face the axial
di rec t ion.
[Claim 3]
The shaf t sea l ing apparatus according to claim 1 or 2, fur ther
compr i s ing a prot ect ion plate having a sur f ace facing the radial
di rec t ion of the rotor and curved and extending in the ci rcumfe rent ial
23
di rec t ion of the annular space,
whe rein the protect ion plate i s we lded to a radia l out er end of the
seal body.
[Claim 4]
The shaf t sea l ing appa ratus according to claim 2 or 3, whe rein the
high-pre s sure s ide latera l plate i s formed wi th an elas t i c element
pres sur izing a pa r t of the high-pres sure s ide lateral pl ate f rom the
high-pre s sure s ide region toward the low-pres sure s ide region.
[Claim 5]
A rotat ing machine compr i s ing the shaf t seal ing appa ratus
according to any one of claims 1 to 4.