STERN TUBE SEALSTERN KEEPER C-TYPE
MANUALCONTENTS
CHAPTER 1 DESCRIPTION OF SAFETY
1 LIST OF WARNING ········································································································· 32 LIST OF CAUTION ········································································································· 4
CHAPTER 2 OUTLINE ·················································································································· 5
1 INTRODUCTION ············································································································· 5
2 SPECIFICATION ··········································································································· 5
2.1 SEAL TYPE ···················································································································· 5
2.2 PLANNED CONDITION ······························································································ 5
3 PERFORMANCE ·············································································································· 6
4 ASSEMBLY SPECIFICATION ···················································································· 6
CHAPTER 3 STRUCTURE AND OPERATION
1 FUNDERMENTAL STRUCTURE ················································································ 7
2 DETAILED STRUCTURE ······························································································ 7
2.1 CASING ····························································································································· 7
2.2 ROTATING SEAL RING ······························································································ 8
2.3 SEAL RING ······················································································································ 8
2.4 CONTRACTIBLE SEAL ······························································································ 8
CHAPTER 4 HANDLING PROCEDURE
1
PREPARATION BEFORE RUN ················································································ 9
1.1 NORMAL RUN ················································································································ 9
1.2 AFTER LONG STOPPAGE OR DISMANTLE MAINTENANCE ··················· 92
OPERATION PROCEDURE ······················································································· 9
2.1 OPERATION DURING RUN ······················································································ 9
2.2 NOTE DURING RUN ·································································································· 10
3 ACTION AFTER RUN ·································································································· 10
3.1 NORMAL RUN ·············································································································· 10
3.2 LONG STOPPAGE ····································································································· 10
4 CONTRACTIBLE SEAL OPERATION PROCEDURE ······································ 10
4.1 PREPARATION ············································································································ 10
4.2 OPERATION ·················································································································· 10
4.3 CANCELLATION ········································································································· 10-1-CHAPTER 5 MAINTENANCE
1 MAINTENANCE LIST ··································································································· 11
2 TROUBLE AND ACTION ···························································································· 14
3 DISMANTLE, ASSEMBLY, INSPECTION AND ADJUSTMENT ·················· 15
3.1 DISMANTLE, ASSEMBLY AND MAINTENANCE ··········································· 15
3.1.1 REPLACEMENT OF ROTATING SEAL RING ·············································· 15
3.1.2 REGRINDING OF SEAL RING ············································································ 17
3.1.3 STANDARD SIZE & REPLACEMENT BASE SIZE OF SEAL RING ····· 17
3.1.4 SLEEVE REGRINDING LIMIT ············································································· 18
3.1.5 REPLACEMENT OF CONTRACTIBLE SEAL ··············································· 18
3.1.6 REPLACEMENT OF ANTICORROSING PLUG ··········································· 18
3.1.7 ASSEMBLY AND INSTALLATION ···································································· 18
ATTACHMENT DRAWING ························································································· 21-2-

CHAPTER 1 DESCRIPTION OF SAFETY
1
LIST OF WARNING
The WARNING items in this manual are shown in TABLE 1-1.
The “WARNING” means the operation or the maintenance which would cause an accident
resulting injury or death in case they are not kept.
TABLE 1-1 LIST OF WARNINGWARNING
PAGE NO
9 2.1
10

2.2

11

1

12

1

STATEMENTITEM
Operation
during run
Noteduring run
Maintenance
List

Maintenance
List

OUTLINE OF
WORK AND OPERATION
Check temperature by hand touchoutside of SEAL RING②.
Check temperature of SEAL RING② to benormal.
Check temperature by hand touch outsideof SEAL RING②. Once a week.
Check ANTICORROSING PLUG㉘ every 3months after operate CONTRACTIBLE
SEAL⑤ and close water supply valve.
Check ball valve, pressure gauge on
VALVE UNIT㉗ once a year.
Re-grind SEAL RING② oncea year, replace ROTATING SEAL RING①,
BAND ⑨ and O-RING⑥ in case of large
water leakage .
Re-grind SEAL RING②, replace
ROTATING SEAL RING ① ,BAND ⑨ and
O-RING⑥ every 2 or 3 years.
Clean VACUUM EJECTOR ⓕ of VALVE
UNIT㉗ every 2 or 3 years.
Check the SEAL DEVICE including
bolts, nuts etc at periodical inspection
Replace CONTRACTIBLE SEAL⑤,
and O-RING㉙ at periodic inspection.

-3-

MEANING OFWARNING
Not to touchrotating shaft.
Not to touchrotating shaft.

To performthe work
duringshaft-stop.

To performthe work
during shaft
stop and dry
dock stay.

TABLE 1-1 LIST OF WARNING （Continued）
WARNING
STATEMENTPAGE NO
ITEM
13 1
Maintenance
List

OUTLINE OF
WORK AND OPERATIONOn removing the SHAFT, peel off oldpaint and apply ANTICORROSING PAINT .
When the SLEEVE is re-grinded on the
SHAFT removing, replace
ROTATING SEAL① and BAND⑨ as well.

MEANING OFWARNING
To perform thework duringshaft-run stopand dry dockstay.

When dismantling the SEAL DEVICESHEET PACKING⑦ is replaced as well.
15

3Dismantle,
assemble,
inspection
andadjustment

Replace ROTATING SEAL RING①.

To stopshaft-rotation.

Remove SEAL RING②.

Not to drop
Split SEAL
RING② whenremoving it.

２. LIST OF CAUTION
The CAUTION items in this manual are shown in TABLE 1-2.
The “CAUTION” means the operation or the maintenance which would cause an accident resulting
device damage in case they are not kept.
TABLE 1-2 LIST OF CAUTIONWARNING
PAGE
9

NO
1

2.1

10

16

STATEMENT

2.2

3

ITEM

OUTLINE OF

MEANING

WORK AND OPERATION

OF WARNING

Preparation

a1 for air release on
Check BALL VALVE○

Not to operate

before run

VALVE UNIT㉗ is opened fully and

CONTRACTIBLE

PRESSURE GAUGE shows 0 MPa.

SEAL⑤ during

Operation

Check that CONTRACTIBLE SEAL⑤

shaft run.

during run

is not working.

Note

Check that pressure gauge ofduring run

VALVE UNIT㉗ is 0 MPa.

Dismantle,

After dismantle, assembly, inspection

assemble,and adjustment in the sea, cancel

inspection

CONTRACTIBLE SEAL⑤ operation.

andAfter dismantle, assembly, inspection &Heat would be

adjustment

adjustment in the sea, release PLUG㉓

generated on

and discharge air in the SEAL DEVICE.

SEAL RING①,②.

-4-

CHAPTER 2 OUTLINE
1. INTRODUCTION
This SEAL DEVICE (STERN KEEPER TYPE SKC) is a kind of END FACE SEAL DEVICE
lubricated with sea water.
The structure is simple with applying rubber elasticity and meets complex vibration fromshaft system completely.
The synthetic rubber (NBR) and stainless steel (SUS316) or bronze (CAC403) are applied
to the sealing face (contacting face of ROTATING SEAL RING① and SEAL RING②).
The characteristic of the SEAL DEVICE is as follows.
(1) The shaft abrasion, which is caused in case of conventional grand packing, is not happened
as there is not the sealing face on the SLEEVE.
(2) The ROTATING SEAL RING① is made of elastic rubber and thrust pad on both front andｒear of ROTATING SEAL RING① and has a good performance of followability to axial
and radial deflection.
(3) The installation work is easy.
(4) The corrosion-proof countermeasures are introduced in the SEAL DEVICE.
(5) As the CONTRACTIBLE SEAL⑤ for emergency is installed, it is available to stop waterleakage and replace ROTATING SEAL RING① by supplying air in the sea.
(6) As both end faces of SEAL RING② are available to use, the action is easy to take incase of emergency. Furthermore it is available to re-use SEAL RING② by re-grinding
the sealing face.

2. SPECIFICATION
2.1 SEAL TYPE END FACE SEAL DEVICE BY SEA WATER LUBRICATION
2.2 PLANNED CONDITION(1) Cooling water : Sea water(2) Sleeve material : CAC402+0.5%Ni(3) Cooling water pressure (normal): draught pressure + 0.01～0.04 MPa(4) Cooling water pressure (Max) : Max. 0.15 MPa(5) Water volume of cooling water : Min. 10L/min
In case of water supply to RUBBER BEARING.
Water volume = ｛SLEEVE Dia. (cm)｝2×5.9÷1000m3/h
Please contact specified bearing supplier when not rubber bearing.
(6) Air pressure to work CONTRACTIBLE SEAL⑤ : 0.2～1.0 MPa-5-3. PERFORMANCE
The performance of the SEAL DEVICE is shown in TABLE 2-1.
TABLE 2-1 PERFORMANCE LIST
FACTOR

SPECIFICATION

Leak water volume

0～50L/day

500 L/day

Shaft surface speed limit

Max. ８m/s

Max. 10m/ｓ

Pressure of cooling water

Min. 0.035MPa

Max. 0.15MPa

Temperature of cooling water

0～35℃

Max 40℃

Temperature of SEAL RING

0～40℃

Max 50℃

0.2～1.0 MPa

1.0 MPa＊Pressure of CONTRACTIBLE SEAL

＊ ：During shaft-run, it is not available to use.

4. ASSEMBLY SPECIFICATIONThe clearance tolerance between CASING③ and the SLEEVE is shown in TABLE 2-2.
The squareness tolerance between the seal installation face and the SLEEVE is shown TABLE 2-3.

TABLE 2-2 CLEARANCE TOLERANCESHAFT DIAMETERDIMENSIONATABLE 2-3 SQUARENESS TOLERANCESHAFT DIAMETERSQUARENESS (a)φ ７０～φ１４９３±０．５

φ ７０～φ１４９０．２

φ１５０～φ２０９４± １

φ１５０～φ２０９０．３

φ２１０～φ６９９６± １

φ２１０～φ３９９

０．５

φ４００～

０．８

(mm)

(mm)

-6-

CHAPTER ３ STRUCTURE AND OPERATION
1. FUNDERMENTAL STRUCTURE (DRAWING ３－１，３－２)
The SEAL DEVICE consists of dynamic components which is installed on the SLEEVE and static
components which is installed on the end face of the STERN TUBE.
Both the impact resilience of seal lip and the water pressure applied to the back face of
ROTATING SEAL RING① provides with sealing pressure.
Some grooves are prepared on the thrust pad on lip side of ROTATING SEAL RING① and can replacecooling water to seal lip.
The CONTRACTIBLE SEAL⑤ is U-shaped, rubber made ring. The air is applied to the inside of it andshrink it to prevent the water leakage.

DRAWING 3-1

DRAWING 3-2

CROSS SECTIONCROSS SECTION OF

OF SEAL DEVICEROTATING SEAL RING

2. DETAILED STRUCTURE
2.1 CASING
The CASING③ with CONTRACTIBLE SEAL⑤ is installed on the face of the STERN TUBE andｔhe SEAL RING② is fixed on the bow side of CASING③.
To prevent corrosion between the SHAFT and CASING③, the end face of the STERN TUBE isinsulated with SHEET PACKING⑦ and BUSH⑧. To prevent corrosion, between hull andcompressed air system of CONTRACTIBLE SEAL⑤ is insulated with TUBE㉛.
The piping system for cooling water is insulated with RUBBER HOSE㉑.

-7-

2.2 ROTATING SEAL RINGThe ROTATING SEAL RING① is installed between CASING③ and SEAL RING② and then fixedwith BAND⑨.
It is made of synthetic rubber(NBR) with excellent performance of water proof, abrasion-proof andsealing. The spare ROTATING SEAL RING① is set on bow side and the replacement of it is very
easy in the sea.
The ROTATING SEAL RING① plays important role to seal the water with SEAL RING②.

2.3 SEAL RINGThe SEAL RING②, which is fixed on CASING③, is made of stainless steel(SUS316) or bronze(CAC403).
It is split into two pieces.
Both end faces of it are available to use as the sealing faces and one of them is prepared as anothersealing face.
The sealing face must be kept not give any flaw.
The sealing face, where is contacting with ROTATING SEAL RING①, is the most important portion.
After it is finished finely with a lathe machine, it is polished with sand paper(No.240) neatly.
When the sealing face is re-grinded with a lathe machine, chuck the outside of the SEAL RING②
not to open the split of it.

2.4 CONTRACTIBLE SEALThe CONTRACTIBLE SEAL⑤ is made of rubber (NBR) and put into CASING③ and held with
STOP RING④.
The CONTRACTIBLE SEAL⑤ is used when the SEAL RING② or ANTICORROSING-PLUG㉘
is replaced in the sea.
By supplying air (0.2～1.0 MPa), the CONTRACTIBLE SEAL⑤ is shrink inside and tighten the SHAFT
and stop water leakage.
Accordingly, it is not used except the above case.
When the CONTRACTIBLE SEAL⑤ is operated for a long time, not to enclose a compressed air for along time from BALL VALVE of VALVE UNIT㉗ but always keep to supply compressed air.
As the CONTRACTIBLE SEAL⑤ is not use during shaft running, discharge air after it is used.

-8-

CHAPTER 4 HANDLING PROCEDURE
1 PREPARATION BEFORE RUN
1.1 NORMAL RUN
a1 for air release on VALVE UNIT㉗ is opened fully and the(1) To confirm that the BALL VALVE○pressure gauge shows 0 MPa.
CAUTIONNOT TO OPERATE THE CONTRACTIBLE SEAL⑤ DURING RUN.

(2) To confirm that the pressure of cooling water is 0.035MPa＜P＜0.15 MPa with pressure gauge on
pipe.
(3) To confirm that the cooling water is running with pressure gauge and touching cooled water pipe.
(4) To confirm that the water is not leaking anywhere except sealing face.

1.2 AFTER LONG STOPPAGE OR DISMANTLE MAINTENANCE(1) After leave dock, to confirm that the air is discharged after PLUG㉓ on CASING③ is released
and the water is supplied to the SEAL DEVICE.
(2) To confirm the note in accordance with previous item 1.1(NORMAL RUN)

2. OPERATION PROCEDURE
2.1 OPERATION DURING RUN(1) To confirm that the cooling water is running with pressure gauge.
(2) To confirm that the water is not leaking and check the volume of it if any.
(3) To touch the outside of SEAL RING② and confirm the temperature of it.
WARNINGNOT TO TOUCH THE ROTATING SHAFT TO CHECKTHE TEMPERATURE.
(4) To confirm that the pressure gauge on VALVE UNIT㉗ is 0MPa.
CAUTIONNOT TO OPERATE CONTRACTIBLE SEAL⑤ DURING RUN.

-9-

2.2 NOTE DURING RUN(1) To confirm that the pressure of cooling water is normal.
(2) To confirm that the volume of leaked water is normal.
(3) To confirm that the temperature of SEAL RING② is normal.
WARNINGNOT TO TOUCH THE ROTATING SHAFT(4) To confirm that the pressure gauge on VALVE UNIT㉗ is 0 MPa.
CAUTIONNOT TO OPERATE CONTRACTIBLE SEAL⑤ DURING RUN

3. ACTION AFTER RUN
3.1 NORMAL RUN(1) To confirm the water leakage during shaft-stop.
(2) To stop the supply of cooling water to the BEARING.

3.2 LONG STOPPAGE(1) In case of stop over one week, to supply the water to the SEAL DEVICE once a week.
(2) To confirm the note in accordance with previous item 3.1 (NORMAL RUN)

4. CONTRACTIBLE SEAL OPERATION PROCEDURE
4.1 PREPARATION
To open BALL VALVE○a2 of VALVE UNIT㉗ and discharge drain of VACUUM EJECTORⓕ.
a1
To confirm that the air is discharged by putting hand on air discharge side of BALL VALVE○of VALVE UNIT㉗. Clean VACUUM EJECTORⓕ if the air-discharge is too weak.

4.2 OPERATIONTo close BALL VALVE○
a1 for air release of VALVE UNIT㉗ and supply compressed air
a2 .
(0.2～1.0 MPa) to CONTRACTIBLE SEAL⑤ by opening BALL VALVE○

Accordingly, the CONTRACTIBLE SEAL⑤ is shrunk to tighten the SLEEVE for sealing.
But the CONTRACTIBLE SEAL⑤ is not available to use during shaft-run.

4.3 CANCELLATIONTo close BALL VALVE○a2 of VALVE UNIT㉗. Open BALL VALVE○a2 after opening
a1 , sucks out air enough through the copper pipe for 10 to 20 sec.
BALL VALVE○a2 .
After that, close the BALL VALVE○-10-CHAPTER

5MAINTENANCE

The MAITENANCE LIST of SEAL DEVICE is shown in TABLE 5-1.
As the maintenance frequency below is standard term, please implement it per actual condition
TABLE 5-1 MAINTENANCE LISTFREQUENCY
Every day

MAINTENANCE

ACTION FOR

ITEM

SAFETY

IMPLEMENT PROCEDURE

Check cooling

1.Check pressure gauge

Water supply to

2.Check cooled pipe with

the BEARING

hand touch.

NOTE

3.Clean filter of cooling water
system. (Draught pressure+ 0.01～0.04 MPa)
Check leaked

Optimum volume is 0～50L/day.

water volume

In case of larger volume, Referto 5-2. (Trouble and Action)

Once a week

Check

WARNING

Below 50℃ is normal. In casetemperature

Not to touch

the shaft temperature is tooof thethe SHAFT

high to touch, refer To 5-2.

SEAL RING(Trouble and Action)Long stoppage

Cooling water

In case of long stoppage in thein the sea.

Supply to thesea, supply water to the STERN(Over a week)

BEARINGTUBE and replace water in
the STERN TUBE once a week.

Once every

ANTICORROSIWARNING

In case dimension (t) is below

Operatethree months

NG PLUG㉘

To check

1 mm, replace it .(dimension(t)CONTRACTIB-

check

duringof new one:10mm) Note) In case

LE SEAL⑤ andshaft-stopof shaft-diameter below Ф99,

close water

the dimension (t) is 5 mm.

supply valve
and start towork.

DRAWING 5-1
Dimension (t) of
ANTICORROSING PLUG

-11-

TABLE 5-1 MAINTENANCE LISTFREQUENCY

Once a year

(Continued)

MAINTENANCE ITEMACTION FOR
SAFETY

IMPLEMENT PROCEDURE

Check ball valve and

WARNING

In case trouble or damage ispressure gauge ofTo implementfound , replace it.

VALVE UNIT㉗

duringReplacement ofshaft-stop

NOTE

Only when the leaked water is

ROTATING SEAL RING①

over 100L/day, replace it.

Replacement of BAND⑨Only when the ROTATINGSEAL RING① is replaced, theBAND⑨ is replaced as well.

Re-grind of SEAL RING②

Only when the leaked water isover 100L/day, re-grind it.

Replacement of

Only when the SEAL RING②

O-RING⑥

is replaced , the O-RING is
replaced as well.

Replacement of

WARNING

Replace to new one. (Spare

ROTATING SEAL RING①

To implement

ROTATING SEAL RING① isOnce every

duringset on the SHAFT and thentwo or three

shaft-stopbonded .)years

Replacement

It is replaced with ROTATING

of BAND⑨SEAL RING① replacement.

Re-grinding

Re-grind it.

of SEAL RING②

Periodic

Replacement

Replace

If replaced to new one andof O-RING⑥

to new

passed over 3 months,

one

replace to new one again.

Cleaning of

Remove it from

VACUUM EJECTORⓕVALVE UNIT㉗ and clean it.

Check the SEAL DEVICE,WARNING

Remove from hull and cleanbolt, nut etc

To implement

each components.

duringIf corrosion, damage anddry-dockdegrading are found, replace tostay andnew one or repair it.

shaft-stop

Replacement to new one.

inspection

Replacement of
CONTRACTIBLE SEAL⑤
Replacement

Replacem

If replaced to new one andof O-RING㉙.

ent topassed over 3 months,

new one.

replace to new one again.

-12-

TABLE 5-1 MAINTENANCE LIST (Continued)
ACTION FORFREQUENCY

MAINTENANCE ITEM

Periodic

Application of

WARNING

Peel off old paint on the

In case ainspection

ANTICORROSING PAINT

To implement

SLEEVE and applyroughduringANTICORROSING PAINT.

surface isshaft-stop

Refer to assembly drawing

found, makefor paint area.

it smooth

SAFETY

IMPLEMENT PROCEDURE

NOTE

with sandpaper.
In case the SLEEVE is re-grinded, items below are implemented in addition.
Replacement of

WARNING

Replacement to new one.

ROTATING SEAL

To implement(NEW SIZE)

RING①duringReplacement ofshaft-stop

BAND⑨

Replacement to new one.
(NEW SIZE)

Each dismantle Replacement of

WARNING

Replacement to new one.

Apply awork

To implement

when it is removed at

liquidduringdismantle work.

packing to

SHEET PACKING⑦

shaft-stop

-13-

set.

２ TROUBLE AND ACTION
The TROUBLE AND ACTION is shown in the TABLE 5-2
TABLE 5-2 TROUBLE AND ACTION
TROUBLECAUSE

ACTION

Large water

・Abrasion of

Optimum volume of leaked water is about 0～50L/day Evenleakage

ROTATING

if the water is increased over 500L/day, adjustment is

SEAL RING①

not necessary. As the water level is changed periodically,

・Abrasion ofcheck it for four or five days. And in case the water level is

SEAL RING②

not decreased, take the actions below.

・Bite of dusts on(1) Remove SEAL RING② and repair rough surface tosealing facemake smooth with sand paper etc.

・Step on sealing(2) In case the water level is not decreased after the action

face of split(1), replace ROTATING SEAL RING① to spare one andportionreverse SEAL RING②. In case the SEAL RING② is
re-grinded, the ROTATING SEAL RING② must be
replaced to new one.
(3) The step on split portion is smoothed with sand paper.

Temperature of

The air is held in

Release PLUG㉓ of CASING③ and discharge air

SEAL RING

the SEAL DEVICE

in the SEAL DEVICE and water supply system.

is very high.

Cooling water isCheck valve operation.

not supplied.

Check pump and pipe system.

CONTRACTIBLE

Open BALL VALVE ○a1 for air discharge of

SEAL is working

a2 and release
VALVE UNIT㉗ and close BALL VALVE ○CONTRACTIBLE SEAL⑤ operation.
Sealing face is

In case the ROTATING SEAL RING① is replaced, the heat

not fitting.

is generated until the sealing face is fitted. Release
PLUG㉓ of CASING③ and discharge sea water to cool andwait the sealing face is fitting. (20～30 hr) In case thetemperature is increased, supply water to location (mark↓)
on DRAWING 5-2 and cool it.

DRAWING 5-2 SEAL RING
Pressure of cooling

Water supply is

Check valve operation. Check pump, piping system andwater is too low.

disturbed.

filter etc.

-14-

3 DISMANTLE, ASSEMBLY, INSPECTION AND ADJUSTMENT
3.1 DISMANTLE, ASSEMBLY AND MAINTENANCE
3.1.1 REPLACEMENT OF ROTATING SEAL RING
Below is procedure to replace ROTATING SEAL RING① in the sea.
Refer to (6)～(14) to replacement in dry dock.
WARNINGTO STOP SHAFT-ROTATION(1) Stop water supply to the BEARING.
(2) Preparation before CONTRACTIBLE SEAL⑤ operation.
(Note: To stop shaft-rotation. Refer to CHAPTER 4. HANDLING PROCEDURE)
a1 for air release of VALVE UNIT㉗ to supply the air to(3) Close BALL VALVE○CONTRACTIBLE SEAL⑤.
a2 of VALVE UNIT㉗ and increase air pressure slowly to(4) Open BALL VALVE ○reach 0.2～1.0MPa.
(5) Release PULG㉓ to discharge the air and confirm that CONTRACTIBLE SEAL⑤
is working.
(6) Remove NUT⑰ and BOLT⑫ and then remove SEAL RING②.
As there are GUIDE PIN⑲ is in SEAL RING②, open it both side equally.
In case GUIDE PIN⑲ is bent, it must be replaced.
WARNING NOT TO DROP SPLIT SEAL RING② WHEN REMOVING IT(7) Clean spare sealing face of SEAL RING②.
(8) Take out ROTATING SEAL RING① with PULL-OUT JIG from notch as DRAWING 5-3.
On this occasion, pull out ROTATING SEAL RING① as its circumference comes out evenly.

DRAWING 5-3 PULLING-OUT PROCEDURE OF SEAL RING

-15-

（9） Remove BAND⑨ after release BOLT⑮. Cut ROTATING SEAL RING① with a knife and remove
it from the SLEEVE.
(10) Clean thrust pad of CASING③ and surface of the SLEEVE and apply grease on them and inside
diameter area of ROTATING SEAL RING① as well.
(11) Clean and degrease split portion of SEAL RING②. And connect split portion with BOLT⑫ after
liquid packing is applied on it.
(The connection location is beyond ROTATING SEAL RING② of bow side) On this occasion, thestep on sealing face is not acceptable. The step is finished to be smooth with sand paper.
(Refer to DRAWING5-4)

DRAWING5-4
LIQUID PACKINGAPPLICATION ON
SEAL RING②(12) Clean the sealing face of ROTATING SEAL RING① and SEAL RING② And apply grease on them.
(13) Pushing spare ROTATING SEAL RING① with SEAL RING②, move spare ROTATING SEAL RING①
into CASING③.

DRAWING 5-5

INSTALLATION PROCEDURE OF SEAL RING

-16-

(14) Fix SEAL RING② with NUT⑰.
(15) Release CONTRACTIBLE SEAL⑤ operation.
(Refer to CHAPTER 4. HANDLING PROCEDURE)
CAUTION NOT TO OPERATE CONTRACTIBLE SEAL DURING RUN.
(16) Release PLUG㉓ and discharge air inside of the SEAL DEVICE.

CAUTIONTHE HEAT GENERATION WOULD BE CAUSED IN ROTATING SEAL
RING①, ②.

3.1.2 RE-GRINDING OF SEAL RING
After remove NUT⑰ and BOLT⑫, take off SEAL RING② from CASING③. Then re-grind the sealing facetill the abrasion is disappeared. The surface roughness of sealing surface must be below 1.5μm Ry. The
trace out of a lathe machine must be cleaned with sandpaper (No.120～240) The chuck of a lathe machine
is tightened from outside. The split portion is opened if the chucking is done inside. In case the split portion
is opened even if they are tightened with bolts, re-grind the split portion.
When thickness [t] changes to low-limit, replace to new one (DRAWING 5-6)

DRAWING 5-6 THICKNESS ［ｔ］ of SEAL RING

3.1.3 STANDARD SIZE ＆ ＲＥＰＬＡＣＥＭＥＮＴ ＢＡＳＥ ＳＩＺＥ ＯＦ SEAL RINGSEAL RING②

(mm)

SHAFT
DIAMETERORIGINALTHIKNESSLIMIT TOTALTHICKNESS
TO RE-GRIND

LIMIT TOTALTHICKNESS TO
RE-GRIND ONE SIZE

φ 70～φ 99

１２

８

2

φ100～φ149

１６

１０

3

φ150～φ209

２０

１３

3.5

φ210～φ399

２４

１６

4

φ400～φ699

２６

１８

4

-17-

3.1.4SLEEVE RE-GRINDING LIMITThe SLEEVE is re-grinded because of abrasion and corrosion. The applicable re-grinding dimension
per SLEEVE SIZE is as follows.
DIAMETER OF SLEEVE(mm)MAX RE-GRINDING MARGIN (mm)

Ф ７０～Ф１４９

２ IN DIAMETER

Ф１５０～Ф２０９

３ IN DIAMETER

Ф２１０～Ф３９９

５ IN DIAMETER

Ф４００～Ф６９９

７ IN DIAMETER

In case the SLEEVE is re-grinded over the dimension above, replace to new
SEAL DEVICE with new dimension.

3.1.5

REPLACEMENT OF CONTRACTIBLE SEAL (per each shaft removal)(1) Remove both SEAL RING② and ROTATING SEAL RING①.
(2) Remove CASING③ from the STERN TUBE.
(3) Take off BOLT⑭ and remove STOP RING④ from CASING③.
(4) Remove both CONTRACTIBLE SEAL⑤ and O-RING㉙.
(5) Re-assembly is implemented in accordance with 3.1.7 (ASSEMBLY AND INSTALLATION)

3.1.6

REPLACEMENT OF ANTICORROSING PLUG

In case the replacement in the sea is implemented, it is done after implementation of
3.1.1 (REPLACEMENT OF ROTAION SEAL RING (1)～(5) ).

3.1.7

ASSEMBLY AND INSTALLATION (REFER TO DRAWING５-７～５-９)(1) Clean CASING③ and STOP RING④ and check there is not any flaw on the contacting face with
CONTRACTIBLE SEAL⑤. ( In case there is any sludge etc. on the contacting face of CONTRACTIBLE
SEAL⑤ with CASING③ and STOP RING④, clean it with a sandpaper etc. and finish it to becomesmoothly.)(2) Apply water-proof grease thinly on the location marked ////on CASING③.
(3) Apply water-proof grease thinly on one side (CASING③ side) of CONTRACTIBLE SEAL⑤ and push
it into CASING③. As the outside diameter of CONTRACTIBLE SEAL⑤ is larger than the inside
diameter of CASING③, push one part of it in first and the other part in order.
(4) Apply water-proof grease thinly on one side(STOP RING④ side) of CONTRACTIBLE SEAL⑤
which is set in CASING③.
(5) Install O-ring㉙ into the groove of CASING③.
(6) Apply water-proof grease thinly on the location marked ////on STOP RING④ and fix it on CASING③
with BOLT⑭．(BOLT⑭ must be tightened in order diagonally.)-18-

DRAWING 5-7 INSTALLATION PROCEDURE OF CONTRACTIBLE SEAL
(7) Put SHEET PACKING⑦ on the back of CASING③ with rubber adhesive.
(8) Clean the end face of the STERN TUBE.
(9) Put CASING③ on the end face of the STERN TUBE with BOLT⑩.
(10) Check the arrangement of CASING③ with marking TOP. The clearance between
top/bottom and right/left must be arranged equally. (Refer to P.6 TABLE 2-2)

DRAWING 5-8

CLEARANCE ADJUSTMENTBETWEEN SHAFT SLEEVE AND CASING(11) Before the SHAFT is installed in the STERN TUBE, apply ANTICORROSING PAINT on the location
where the SEAL DEVICE is installed widely.
(Refer to attachment drawing-1)(12) Installation onto the SHAFT
When the SHAFT is installed into the BEARING of the STERN TUBE from stern side, an watchman,
who stays inboard, checks if the SHAFT is inserted correctly.

-19-

DRAWING 5-9

INSTALLATION

ORDER

OF

SEAL RING(13) Put BAND⑨ on the outside of ROTATING SEAL RING① and tighten it with BOLT⑮．
(14) Clean the sealing face of ROTATING SEAL RING① and SEAL RING②, the surface of thrust padof CASING③ and the surface of the SLEEVE. Then apply a grease on them thinly.
(15) Pushing forward ROTATING SEAL RING① with SEAL RING②, move ROTATING SEAL RING①
into CASING③.
(16) Fix SEAL RING② with NUT⑰.
(17) Put spare BAND⑨ on the band groove of spare ROTATING SEAL RING① and tighten with BOLT⑮.
On this occasion , not to make SEAL RING② touch.
(18) Install TUBE FITTING㉕ for piping to supply compressed air to CONTRACTIBLE SEAL⑤.
Then connect VALVE UNIT㉗ and the SEAL DEVICE side with Ф10mm COPPER PIPE㉚.
On this occasion , fix ISOLATION TUBE㉛ on COPPER PIPE㉚ with hull to prevent corrosion.

-20-