Strentube

IHC LAGERSMIT Installation and maintenance instructions SUPREME®
stern tube seals
02/05 1
CONTENTS
CHAPTER PAGE
DATA SHEET 2
1. INTRODUCTION 3
2. GENERAL 4
3. INSTALLATION INSTRUCTIONS SUPREME STERN TUBE SEAL 7
4. PUTTING INTO OPERATION 14
5. MAINTENANCE / REPAIRS 16
6. OPTIONAL EXTRA’S 19
ENCLOSURES
WEAR DOWN PROTOCOL
SPARE PARTS / SERVICE
TYPE APPROVAL CLASS. (copy)
ASSEMBLY DRAWING AFT SEAL
ASSEMBLY DRAWING FORWARD SEAL
DRAWING CIRCULATION OILTANK
DRAWING 20 L. OIL TANK
DRAWING LUBRICATION SCHEME
_____________________________________________________________________
_____________________________________________________________________

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DATA SHEET SUPREME®
SUPREME®
aft seal SUPREME®
forward seal
Size
Type
Serial no
Drawing no
IHC Lagersmit order no

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1. INTRODUCTION
This manual is for the professional assembly, maintenance and dismantling of the SUPREME®
∗
stern tube seal and is intended for those persons who have to carry out above mentioned tasks.
The products of IHC Lagersmit BV∗∗ have been designed and manufactured to reflect the
technological state of the art. Nevertheless, it cannot be ruled out that danger may arise to:
• Life and limp;
• the product and/or overall plant;
• other aspects.
Make sure the safety instructions given in this manual are carefully observed.
Where needed, the instructions in this manual are supplied with symbols for specified dangers:
: danger to life and limb
: danger to the product and/or the overall plant
: danger to other aspects
In particular, hazards may occur:
• if insufficiently trained personnel manipulates the product;
• if the product is inexpertly installed, operated and serviced;
• if the product is used for other than the intended purposes.
Beside the danger symbols above the next symbol is used in this manual:
: attention to notes
All persons responsible for the operation of the product must:
o be familiar with the contents of this manual;
o have adequate technical qualifications and are authorized to perform the relevant activity.
No modifications to the product are permitted unless the prior approval of IHC Lagersmit is obtained.
The content of this specification is the property of IHC Lagersmit and may not be brought to the
knowledge of third parties either in the original form or by reproduction. Although the information in
this manual has been checked and reproduced as carefully as possible no responsibility can be
accepted for faults and/or incompleteness. IHC Lagersmit reserves the right to alter the information
given in this manual without prior warning.
∗
SUPREME is a registrated trademark
∗∗
IHC Lagersmit BV, abbreviated IHC Lagersmit, is a member of the IHC Holland Merwede Group.

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2. GENERAL
2.1 Product description*
The SUPREME stern tube seal system consists of a SUPREME aft seal, an aft bearing
bush, a forward bearing bush and a SUPREME forward seal. The SUPREME stern tube
seals are used for sealing the stern tube at the points where the shaft penetrates. The oil
level in the stern tube tank should be 3 to 4 meters above the loaded water-line (LWL).
Figure 2.1 shows an example of a complete stern tube system.
Figure 2.1: Example of a complete stern tube system
2.1.1 The SUPREME aft seal
The aft seal exists of three rubber lip seals which are clamped in the house parts. The lip
seals are sealing at a corrosion proof liner. The purpose of the aft seal is to prevent (sea)
water ingress and oil outlet from the stern tube.
The lip seals can be replaced without removing the propeller or withdrawing the propeller
shaft.
* A typical model is described. Consult the appropriate assembly drawing for detailed information.

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Figure 2.2: SUPREME aft seal (standard design)
The SUPREME aft seal is also available in a fully split execution, called the SUPREME 2/2.
This seal affords the possibility to replace the lip seals and the liner without removing the
propeller or withdrawing the propeller shaft. The principal of sealing, materials, etc. is equal
to that of the standard SUPREME aft seal.
This manual describes instructions belonging to the standard SUPREME seals.
Additional instructions regarding SUPREME 2/2 aft seals will be stated
separately.
In order to protect the liner against corrosion IHC Lagersmit recommends a
grounded propeller shaft.
2.1.2 Bearing bushes
The bearing bushes of IHC Lagersmit are made of cast iron lined with a white metal bearing
surface. The bearing bushes shown in figure 2.3 must be lubricated with lubrication oil only.
Figure 2.3: Oil lubricated bearing bushes

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2.1.3 The SUPREME forward seal
The forward seal exists of two lip seals which are clamped in the house parts. The lip seals
are sealing at a cast iron liner which is provided with a ceramic surface. This liner is
connected to the shaft with the aid of a splitted clamping ring. The purpose of the seal is to
prevent oil outlet from the stern tube. The lip seals are lubricated with oil from a circulation
tank. The rotation of the propeller shaft together with the presence of a scraper in the seal
forces the oil to circulate.
Figure 2.4: SUPREME forward seal (standard design)
2.2 Handling and storing of the product
If the product is stored for a longer period, the product has to be stored in a clean and dry
place.
The seal must be protected against any kind of damage. IHC Lagersmit recommends storing
the product in the original packaging.

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3. INSTALLATION INSTRUCTIONS SUPREME STERN TUBE SEAL*
The following precautions must be taken before commencing the installation of the SUPREME stern
tube seals.
Precautions:
1. Check the shaft and stern tube for damage and/or dirt;
The shaft and stern tube should be free of imperfections such as dirt and/or damage/burs.
2. Check the goods for transport damage and/or incompleteness;
If any transport damage is noted and/or anything is missing contact IHC Lagersmit.
3. Check the connection sizes;
If the connection sizes do not agree with those in the drawing the stern tube seal cannot be
fitted. In that case consult IHC Lagersmit.
4. Check the pipes and oil tank(s) for internal dirt, damages and leakages
The pipes and tank(s) should be free of imperfections such as dirt, damages and leakages.
3.1 Installing the stern tube aft seal
The SUPREME aft seal is delivered completely assembled, including brackets. In order to
prevent damage to the liner as well as the lip seals, the complete seal must slid onto the
propeller shaft as a unit, including the brackets.
The shaft may not be driven when work is carried out on the seal.
The brackets are not suitable for lifting purposes.
Install:
1. Take the precautions mentioned;
2. Oil the shaft;
3. Fit the complete stern tube seal according the assembly drawing;
Mind the correct position of the gaskets and the bleed plug.
With respect to the alignment don’t secure the bolts of the flange ring yet.
Remove the brackets!
If the brackets are not removed the installation will cause
damage when the seal is put into operation.
The brackets do not determine the built-in length.
4. Couple the propeller shaft and fit the propeller
* Instructions regarding bearing bushes will not be dealt with in this manual.

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5. Check the alignment of the seal according figure 3.1;
Fig. 3.1: Checking the alignment
Measurements must be taken in horizontal and vertical direction. The maximum
allowed difference in measurement A – B depends of the size on the SUPREME
seal, according table 3.1.
SUPREME size
Maximum allowed difference measurements
A1 – B1 and A2 – B2
155 t/m 300 0,35 mm
330 t/m 500 0,40 mm
530 t/m 710 0,45 mm
750 t/m 900 0,50 mm
Table 3.1
6. Check the built-in length according figure 3.2;
Fig. 3.2: Checking the built-in length
The built-in length depends on the size of the SUPREME stern tube seal and is
shown at the assembly drawing.

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02/05 9
7. Check the run-out of the liner according figure 3.3
Fig. 3.3: Checking the run-out
The maximum allowed shaft movement depends on the size of the SUPREME seal.
The next table shows the maximum allowed clock gauge deflections:
SUPREME size Maximum allowed clock gauge deflection
155 t/m 300 0,09 mm
330 t/m 500 0,12 mm
530 t/m 900 0,15 mm
Table 3.2: Maximum allowed clock gauge deflections
8. Fasten and secure the bolts.
Table 3.3 shows the torque moments. The bolts need to be redrawed after fitting.
The bolts have to be secured with the help of securing wire according figure 3.4.
Bolt
Torque moment
Aft seal
Torque moment
Forward seal
M8 20 [Nm] 22 [Nm]
M10 45 [Nm] 44 [Nm]
M12 75 [Nm] 74 [Nm]
M16 120 [Nm] 165 [Nm]
M20 205 [Nm] 314 [Nm]
M24 354 [Nm] 549 [Nm]
Table 3.3 : Torque moments

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Additional instructions for SUPREME 2/2 aft seals:
Bolts have to be tightened uniformly and in order 1 – 2 – 3 – … as shown in figure
3.4.
Figure 3.4: * Tightening order (seen against the flange of a liner 2/2)
* Way of securing
3.2 Zero wear down measurement
The wear down of the aft bearing bush can be determinated without removing the aft seal by
carrying out a zero wear down measurement. This measurement has to be carried out
before launch. The value has to be recorded at the wear down protocol attached in this
manual. This measurement has to be carried out regularly, e.g. at dry-dockings. By
comparing the values to the zero wear down value, it can be determined whether the bearing
clearance is still acceptable.

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02/05 11
Carrying out the zero wear down measurement:
The bearing wear down is to be determined with the use of the vernier callipers and the
measuring plug as shown in figure 3.5.
Figure 3.5: Zero wear down measurement
1. Put the propeller blade #1 at TOP position;
2. Remove the plug and sealing ring from the end supporting ring;
3. Screw the measuring plug into the thread hole;
4. Determine dimension A with the use of the vernier callipers;
5. Write down the measured value at the wear down protocol;
6. Remove the measuring plug and replace the sealing ring and plug.
Use a new sealing ring after each wear down measurement!
3.3 Installing the stern tube forward seal
The SUPREME forward seal is delivered completely assembled, including brackets. In order
to prevent damage to the liner as well as the lip seals, the complete seal must slid onto the
propeller shaft as a unit, including the brackets.
The shaft may not be driven when work is carried out on the seal.
The brackets are not suitable for lifting purposes.

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02/05 12
Installing:
1. Take the precautions written at page 7 of this manual;
2. Oil the shaft;
3. Slid the complete stern tube seal, including the gasket, brackets and O-ring onto the
shaft;
4. Fit the seal against the stern tube;
Mind the correct position of the gasket and the bleed plug.
With respect to the alignment do not fasten the bolts of the flange ring yet.
5. Couple the propeller shaft;
6. Remove the brackets;
If the brackets are not removed the installation will cause
damage when the seal is put into operation.
The brackets do not prescribe the built-in length.
7. Adjust and mount the clamping ring onto the propeller shaft;
The adjusting size is given in table 3.4.
Adjusting
size [mm]
Adjusting
size [mm]
Adjusting
size [mm]
SUPREME
Size
Min. Max.
SUPREME
Size
Min. Max.
SUPREME
Size
Min. Max.
155 to 190 57 67 355 to 380 79 89 670 130 145
200 to 220 62 72 400 to 500 84 99 710 to 750 120 135
240 to 260 67 77 530 89 104 800 to 850 123 138
280 69 79 560 to 600 90 105 900 138 153
300 to 330 74 84 630 105 120 950 to 1000 148 163
Table 3.4: Adjusting sizes

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With respect to the possibility to shove the liner aside to the stern
tube the maximum adjusting size should be realized at new-
building.
8. Fit the liner against the clamping ring;
9. Check the alignment and run-out of the liner;
See paragraph 3.1 (instructions 5 and 7)
10. Fasten the bolts;
See table 3.3 for the required torque moments
11. Fit and connect the lubrication tank according to the drawing attached in this manual
(if applicable);
At all times the seals must be protected against grinding dust and/or welding
spatter.
Wrapping of the seals for example with fibreglass cloths is recommended by
IHC Lagersmit.

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02/05 14
4. PUTTING INTO OPERATION
For putting the propulsion installation into operation see the concerned manuals of the supplier(s) of
the propulsion installation. As for the stern tube seals and bearings the next actions must be taken:
1. Filling the stern tube and stern tube tank;
2. Filling the circulation tank of the forward seal;
3. Filling the additional lubrication oil tank(s). (if applicable)
Observe the safety and environmental rules when filling the tanks.
4.1 Filling the stern tube and stern tube tank
The stern tube and stern tube tank should be filled with lubrication oil* up to the maximum
level. To prevent pressure increase the stern tube must be aerated continuously.
4.2 Filling the circulation tank of the forward seal
The next actions must be taken:
1. Remove the filler plug of the circulation tank;
2. Fill the circulation tank with lubrication oil*;
The circulation tank should be filled up to the upper sight glass
3. Fit the filler plug.
4.3 Filling the additional tank(s) (if applicable)
The next actions must be taken:
1. Open the valve between the additional tank and the aft seal;
2. Remove the bleed plug of the aft seal;
3. Remove the filler plug of the additional tank;
* For oil specifications see paragraph 4.4

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4. Fill the additional tank with lubrication oil;
The additional tank should be filled up until the oil is coming out of the bleed hole of
the aft seal. Because there is no counter pressure the water repellent seals may
loose some oil. For oil specifications see paragraph 4.4.
5. Fit the bleed plug;
6. Close the valve; (see the lubrication scheme in the enclosure)
The valve must be opened after launch.
7. Fit the filler plug.
4.4 Oil specifications
Mineral lubrication oil can be used, provided it is compatible with the next properties:
- ISO VG 68 … ISO VG 320;
- Temperature range: -20 … 120 °C.
Often lubrication oil class SAE 30 / 40 is used.
The lubrication oil may not be polluted.
When the use of specific oil, for example biological-oil, is desired, please contact the oil
supplier concerned.
The installation is ready for start-up after removing the protection cloths of the
seal.
Keep one’s distance to the shaft during start-up!

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5. MAINTANANCE / REPAIRS
The following inspections / actions should be taken periodically:
Periodical Act
Weekly Checking the oil levels (5.1)
Half-yearly Refreshing the lub. oil in the circulation tank of the forward seal
Each docking Measuring the wear down (5.2)
Removing the distance ring (if fitted) (5.3.1.1)
Machining the liner (5.3.1.2)
Overhaul of the
aft seal (5.3.1)
Shortening and fitting the springs of the lip seals (5.3.1.3)
Points of interest at
overhaul
Overhaul of the forward seal (5.3.2)
5.1 Weekly maintenance
Checking the oil level:
At normal operation conditions seals will have little oil consumption. This consumption
depends on a large amount of factors. For instance the size, peripheral velocity,
misalignment, viscosity of the oil, temperature and conditions of the lip seals/liner have a
great influence. Weekly the oil levels in the circulation tank of the forward seal, the stern tube
tank and additional oil tanks need to be checked and filled if necessary.
5.2 Each docking
Measuring the wear down:
Before starting the work the bearing bush wear down needs to be measured. The way of
measuring is the same as the zero wear down measurement as described in paragraph 3.2.
For the maximum allowed bearing clearance contact the concerned classification society.
After the work the zero wear down measurement needs to be redone.
5.3 Points of interest at overhaul
The lip seals can be replaced without removing the propeller or withdrawing the propeller
shaft.
Gluing the lip seals in situ can only be done if the stern tube is free of
oil.
In the event of repairs IHC Lagersmit recommends to renew the lip
seals and other “soft” materials like rubber rings and gaskets.
Overhauling SUPREME seals demands specialistic skills / tools and
therefore needs to be done by a service engineer of IHC Lagersmit or
by a service engineer of a recognized by IHC Lagersmit service station

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5.3.1 Overhaul of the aft seal
In the event of running spurs at the liner there are several options:
5.3.1.1 Removing the distance ring (if fitted)
After removing the distance ring the housing of the aft seal can be shoved aside to
the stern tube. This way new running surfaces are achieved for the lip seals.
5.3.1.2 Machining the liner
When the distance ring has been removed earlier (5.3.1.1) the running surface of
the liner can be turned and/or ground down. The finish should be pitch free. The
roughness (Ra) must be between 0.2 and 0.8 µm.
The spring of the lip seal which will run on a machined down surface should be
shortened according 5.3.1.3
Figure 5.1: Machining the liner
Table 5.1 shows the maximum diameter reduction and the shortened spring length
by 1 mm diameter reduction:
SUPREME size
(Dnominal)
Pmax
(Max. diam. reduction)
Shortened spring length by 1 mm
diameter reduction (see 5.3.1.3)
155 t/m 200 1,5 mm 20 mm
220 t/m 240 1,6 mm 25 mm
260 t/m 280 1,6 mm 30 mm
300 t/m 355 1,6 mm 35 mm
380 t/m 450 1,7 mm 40 mm
480 t/m 530 1,8 mm 45 mm
560 t/m 600 1,9 mm 50 mm
630 t/m 710 2,0 mm 55 mm
750 t/m 800 2,1 mm 60 mm
850 t/m 900 2,1 mm 65 mm
Table 5.1: Maximum diameter reduction / Shortened spring length by 1 mm diameter reduction.
Example: The running surface diameter of a liner size 420 is machined with
1.3 mm to Ø 418.7 mm. This means that the spring must be
shortened to: 1.3 * 40 = 52 mm.

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5.3.1.3 Shortening the springs of the lip seal
The springs of the lip seals can be shortened:
1. Remove the spring;
Screw the spring ends loose by turning the conical spring end left.
2. Shorten the spring;
See table 5.1. for the right length.
NOTE: Do not cut off the conical spring end.
3. Make the spring connection;
Turn the conical spring end to the right into the other spring end.
4. Fit the spring on the lip seal.
5.3.2. Overhaul of the forward seal;
Putting the ship into dock is not always necessary for overhauling the forward seal.
Before such overhaul can take place be ensured the aft seal is watertight.

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6. OPTIONAL EXTRAS
To extend the life of the stern tube seal the SUPREME seal can be fitted with a variety of optional
extras.
1 Rubber material
The lip seals can be made from heat
resistant and stable FPM (Viton®
) rubber in
situations of heavy loads.
6 Springs
The lip seals can be fitted with Hastelloy®
springs. These are better resistant to
corrosion than the standard used stainless
steel springs.
2 Wire winder
Fitting a stainless steel split (2/2) wire
winder prevents thin (fishing) lines being
wound onto the liner.
7 Wear resistant surface
A ceramic or hard metal layer can be
applied to the liner. This reduces the wear
and tear of the lip seals in the liner.
3 Net cutters
Stainless steel net cutters can be fitted on
the rope guard over the overlapping part on
the propeller hub.
8 Static sealing
Fixed propellers can be exchanged without
loss of lubrication oil form the stern tube, if
an O-ring is present between the liner and
the propeller shaft.
4 Cathodic protection
Fitting a sacrificial anode to the liner itself
offers maximum resistance to corrosion of
the liner.
5 Dirt barrier
The ingress of sand particles and other
foreign matter can be avoided by using a dirt
barrier. This rubber dirt barrier is clamped
onto the liner using 2 taut stainless steel
springs.
9 Distance ring
The SUPREME in its standard design can
be fitted with a divisible distance ring. This
extends the life of the aft seal. Removal of
this ring enables the housing to be removed
in relation to the liner with the result that
new sealing surfaces are created for new
rubber lip seals. The spacer ring in fully split
execution (2/2) can also be supplied.

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WEAR DOWN PROTOCOL

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02/05 21
SPARE PARTS / SERVICE
To ensure that the correct parts are supplied the following information must be provided on the order:
1. The information on the data sheet on page 2 of this manual;
2. Description of the required parts;
3. Part number and/or code number of the required parts;
4. Quantity, desired delivery time and sending information of the required parts.
Besides the required information for ordering spare parts the following information should be
provided for ordering a service engineer:
1. Place of docking;
2. Desired starting date.
Orders for spare parts and /or service engineer should be addressed to:
IHC Lagersmit BV
P.O. Box 5
2960 AA KINDERDIJK
Holland
Telephone : +31 (0) 78 69 10 472
Service telephone : +31 (0) 6 539 35 653 (24 h accessible)
Telefax : +31 (0) 78 69 10 477
E-mail : info@ihclagersmit.com
Website : www.ihclagersmit.com

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