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FIELD OF IN VENT10N
The present invention gener lly rel tes to n ir se l device, nd more
p rticul rly, to n ir se l device d pt ble to be ring lube oil se ling system
th t is self powered ided by the rot tion of rotor on which the se l is
mounted.
B <^<3RWMft QF THE XNYEimQN
turbo -gener tor rotor is supported by two journ l be rings, one e ch on its
either end. These be rings re supplied with lubric ting oil to form hydro
dyn mic oil film th t prevents rot ting journ l from coming in cont ct with the
be ring on which the rot tor is
supported.
The qu ntity of oil supplied to e ch be ring is depend nt on sever l
p r meters such s speed of rotor rot tion, weight of rotor, type of be ring
chosen, its oil cle r nces, viscosity of oil nd be ring length nd di meters.
The qu ntity is depend nt on the weight of rotor, higher will be the lube oil
supply s the turbo-gener tor r ting incre ses, in norm l course. Oil is supplied
to he be rings t pressure to ensure th t the oil supply is v il ble between
the n rrow cle r nce between the journ l nd be rings to c rry w y the he t
gener ted by the rotor nd be rings due to rot tion.

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The hot oil is dr ined out continuously for f cilit ting smooth flow of feed oil into the
be ring. The dr in oil is collected t the bottom of ttie be ring pedest ls, where dr in
lines re mounted. To ensure th t the dr in oil is collected tot lly t the be ring
pedest ls nd ensure th t there is no outflow cross the ends of pedest ls, oil se ls re
ssembled to the pedest ls on either end. The oil se ls re st tionery nd mounted on
rot ting sh ft, br ss fins or br ss pl tes re ssembled t tfie interf ce between the
sh ft nd the steel ring with cle r nce. This rr ngement ensures th t the cle r nce
between the sh ft nd the se l c n be minimized nd oil le k ge through the se l
cle r nce is kept s low s possible.
There re sever l rr ngements of oil se ls to scr pe the oil nd dr in the s me b ck
into tiie be ring housings. V rious se ling ring designs s per prior rt re given in
nnexure (1). One type of se ling ring usu lly employed for turbo-gener tor
pplic tion is m de out of steel rings grooved t its bore to ssemble br ss sc rper fin
is shown in fig. 1.1. set of sc rpers re ssembled to f cilit te complete oil scr ping.
nother type of se ling ring is provided with se l ir system where pressurized ir is
supplied to tiie se ls th t oppose ny oil le k ge cross tiie se l cle r nces.
In turbo-gener tors the se ls come in the vicinity of the xi l flow fens th t tend to
cre te suction pressure which counter cts the purpose of se l. While the oil se l
ttempts to scr pe oil nd prevents the oil le k ge into the m chine, the xi l flow fens
ttempt to suck the oil from the se ls.

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speci l rr ngement is necess ry in tiie rotor-be ring system to device se l th t
prevents oil ingress into the gener tor. This is especi lly necess ry when it is required
to optimize the rotor lengths.
For the foregoing re sons, need exists to devise se l tfi t fits in the rotor sh ft-
be ring system th t t kes pressurized ir nd m int ins n ir curt in in the nnul r
sp ce between the sh ft nd the se l. The ir curt in rrests oil le k ge from the
be ring shell into the m chine or into the m chine surroundings. To m ke the se l
comp ct, it is required to power the s me by itself with the help of sh ft rot tion.
OBJECTS Of THE INVENTION
It is therefore, n object of the present invention to propose n ir se l device
d pt ble to be ring lube oil se ling system which elimin tes the oil le k ge from the
be ring shells into the tmosphere.
nother object of the present invention is to propose n ir se l device d pt ble to
be ring lube oil se ling system which cts on providing n ir curt in between sh ft nd
se l.
still nother object of the present invention is to propose n ir se l device d pt ble
to be ring lube oil se ling system which is self powered for obt ining the fen ction of
the se l due to the rot tion of the rotor on which se l is mounted.

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further object of the present invention is to propose n ir se l device d pt ble to
be ring lube oil se ling system which occupies less sp ce in fittings.
still further object of the present invention is to propose n ir se l device d pt ble
to be ring lube oil se ling system which is eco friendly,
SUMM RY OF THE INVENTION
rot ting equipment like turbo-gener tor is supported on two journ l be rings.
These be rings re provided with oil se ls to prevent the circul ting lube oil from
le king out of the be ring oil circuit. There re sever l types of oil se ls in oper tion,
depend nt on the size of the be ring, speed of rotor rot tion, lubric ting medium
employed etc. The se l device in the present invention is m de out of mild steel or
luminum pl te or c sting tii t is m chined outside with semi-circul r projection th t
en bles e sy sliding into n outer pl te. The outer pl te is m de either integr l with
tiie be ring shell or ssembled sep r tely to the shell. The inner periphery th t is
m chined round se ts on step dj cent to journ l with cle r nce m int ined between
it (se l) nd rot ting sh ft. The sh ft is m chined such tti t step of dequ te depth is
formed nd this step gener tes pressure he d when the se l is ssembled such th t it
forms duct with the rotor. The newly device se l is lso provided with inclined holes
on its f ce th t llow ir flow to t ke pl ce. In view of the ngul r

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holes drilled, the whole se l nd sh ft rr ngement ds s fen, The he d thus
gener ted due to rotor rot tion effects the form tion of pressurized ir. The ir is
ch nneled into the sp ce between the se l nd the sh ft to rrest the oil seep ge from
the be rings.
The se ls re ssembled into groves turned on the inner periphery of the be ring shell
shoulders. This construction m kes the se l comp ct s it elimin tes the requirement of
f stening due to the bsence of ny end f stening. The f stening rr ngement in the
convention l se ls requires sp ce between the dj cent rotor step nd the be ring shell
to f cilit te f stener ssembly. This sp ce is elimin ted completely in the new se l
design in view of the semi-circul r projection in the se l nd m tching groove in the
be ring shoulder nd hence m kes it comp ct.
The se l th t h s been invented nd shown in fig. 1.3, occupies sp ce th t f r less
th n the convention l one. It t ke dv nt ge from rotor rot tion nd geometry to
cre te pressure he d th t develops stre m of continuous pressurized ir nd
forming n ir curt in to se l the oil from flowing out of the be ring lube oil system
sp ce. step m de in the rotor body nd shown in fig. 1.3 cts not only to f cilit te fen
ction but cts s gl nd to effect good se ling.
mif PSSCRIrTJiQN QP THE (?CQHP MYW<5 PR WIH3
Fig~l - shows the schem tic di gr m of the oil se l in prior rt.
Rg-2 - shows tiie schem tic di gr m of be ring oil se l in prior rt.
Fig-3» shows the schem tic di gr m of ir se l rr ngement on sh ft
s per present invention.

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DET ILED DESCRIPTION OF k PREFERRED EMBODIMENT OF THE
INVENTION
The present invention comprises se l (6) is ssembled into m chined groves t med
on the inner periphery of the be ring shell (9) shoulder by circumferenti l sliding,
drilling inclined holes (12) on the se l pl ce nd designing the rotor steps dj cent to
rotor (7) th t the rotor cts like gl nd (8) nd se l (6) cts like fen. The ir curt in
(10) formed between the sh ft (7) nd se l (6) present oil le k ge from the be ring
housings (9).

*KY, ftr TMfliil
Reference Number Ch r cter Figure
1 Wind Pl te (Outerse l) 2
2 F stener to Fix Se l 2
3 Rotor Sh ft 2
4 Se ling Right 2
5 Be ring Shell 2
6 Se l ( s per invention) 3
7 Rotor Sh ft 3
8 Rotor Gl nd 3
9 Be ring Shell 3
10 ir flow Direction 3
11 Semi Circul r Proj
on Se l outer Di 3
12 inclined hole on the
on the se l f ce 3

JLSJHLnSUSEJnK tJL
1. n ir se l device d pt ble to be ring lube oil se ling system
comprises: -
- circul r m chined p rt insert ble in m chined grove of the
be ring shell;
- circul r m chine p rt provided with outside semi-circul r
projected p rt th t en bles e sy sliding into n out pl te;
- the m chined p rt is mount ble with rot ting sh ft;
- the rot ting sh ft is m chined such th t step of dequ te depth
is formed nd this step gener tes pressure he d when the se l is
ssembled such th t it forms duct with rotor;
- the m chine p rt is provided with inclind holes on its f ce th t
llow ir flow to t ke pl ce nd cts s fen; nd
- the ir is ch nneled into the sp ce between the se l nd the sh ft
to rrest the oil seep ge from be rings;

2. The ir se l device s cl imed in cl im 1 is m de from mild steel pl te or
luminum pl te or c sting by m chining.
3. The ir se l device s cl imed in cl im 1 where in se ling is self powered
by mounting with the rotor.

A rotating equipment like a turbo-generator is supported on two journal bearings. These bearings are provided with oil seals to prevent the circulating lube oil from leaking out of the bearing oil circuit. There are several types of oil seals in operation, dependant on the size of the bearing, speed of rotor rotation, lubricating medium employed etc. The seal device in the present invention is made out of mild steel or aluminum plate or casting that is machined outside with a semi-circular projection that enables easy sliding into an outer plate. The outer plate is made either integral with the bearing shell or assembled separately to the shell. The inner periphery that is machined round seats on step adjacent to journal with a clearance maintained between it (seal) and rotating shaft. The shaft is machined such that a step of adequate depth is formed and this step generates pressure head when the seal is assembled such that it forms a duct with the rotor. The newly device seal is also provided with inclined holes on its face that allow air flow to take place. In view of the angular

holes drilled, the whole seal and shaft arrangement acts as a fan, The head thus generated due to rotor rotation effects the formation of pressurized air. The air is channeled into the space between the seal and the shaft to arrest the oil seepage from the bearings.
The seals are assembled into groves turned on the inner periphery of the bearing shell shoulders. This construction makes the seal compact as it eliminates the requirement of fastening due to the absence of any end fastening. The fastening arrangement in the conventional seals requires space between the adjacent rotor step and the bearing shell to facilitate fastener assembly. This space is eliminated completely in the new seal design in view of the semi-circular projection in the seal and matching groove in the bearing shoulder and hence makes it compact.
The seal that has been invented and shown in fig. 1.3, occupies a space that for less than the conventional one. It take advantage from rotor rotation and geometry to create a pressure head that develops a stream of continuous pressurized air and forming an air curtain to seal the oil from flowing out of the bearing lube oil system space. A step made in the rotor body and shown in fig. 1.3 acts not only to facilitate fen action but acts as a gland to effect good sealing.