(006)SternTubeBearing_and_Shaft_Seal_Resubmittal.pdf

FRV40-226-006-010

DESCRIPTION, OPERATION, INSTALLATION AND

MAINTENANCE INSTRUCTIONS

Stern Tube Bearing (Thordon Compac) and Shaft Seal (Kobelco)

Halter Marine, Inc.

13085 Seaway Rd.

P.O. Box 3029 Gulfport, MS 39505

50-SPNA-1-00031

PUBLISHED BY DIRECTION OF NOAA

FRV40-226-006-010

DESCRIPTION, OPERATION, INSTALLATION AND

MAINTENANCE INSTRUCTIONS

Stern Tube Bearing (Thordon Compac) and Shaft Seal (Kobelco)

13085 Seaway Rd.

P.O. Box 3029 Gulfport, MS 39505

PUBLISHED BY DIRECTION OF NOAA

18 SEP 2007

RECORD OF CHANGES

Change No.

Date Title and/or Brief Description Signature of Validating Officer

APPROVAL AND PROCUREMENT RECORD PAGE

APPROVAL DATA FOR: FRV40-226-006-010

TITLE OF MANUAL: Stern Tube Bearing and Shaft Seal

APPROVAL AUTHORITY: NOAA

Contract Number

Ship Applicability

Qty Of Manuals

Building Yard

50-SPNA-1-00031 FRV40-226 2 EA Halter Marine Inc.

REMARKS:

CERTIFICATION: It is hereby certified that FRV40-226-006-010 to be provided under contract 50-SPNA- 1-00031 has been approved by the approval data shown above.

Date:________________ Chand, LLC Mathews, LA 70375

CAGE CODE: 0D5X4

VALIDATION PERFORMANCE

Title of Publication

Stern Tube Bearing and Shaft Seal

Contractor Sub-Contractor (If

Performing Validation)

Contract No.(s) and Purchase Orders, If Applicable

Chapter

Section Paragraph Date Validation Completed

Check here if Not Validated

Contents of this manual have been validated and certified to be applicable to the equipment furnished under the above procurement as specified for Validation.

Name & Authority of Validating Officer: Signature of Validating Officer:

FOREWORD

This manual is intended to clearly and accurately reflect the actual configuration of the installed equipment described for the FRV40-226 Stern Tube Bearing and Shaft Seal. Users are urged to report instances noted wherein the manual does not achieve this objective.

This technical manual provides the instructions necessary to operate, to perform maintenance on and troubleshooting of the Stern Tube Bearing and Shaft Seal. The text is broken down as follows:

Section 1- Overview

DanLe Section 2 - System Drawings Section 3 - Thordon Compac Information Section 4 - Installation-Operation Manual Kobelco Water Lubricated Shaft Seal (Type KW)

Section 1 - Overview

The Stern Tube Seal bearing is custom manufactured for the NOAA FRV40-225. The Thordon Compac illustrated parts list is provided in DWG#15312-1A. DWG # 1531-2A illustrates the complete assembly (with the bearing carrier) and the Compac Bearing installed. DWG # 15824 B illustrates a fully finished bearing insert.

Note that the insert is made from two pieces of material in order to achieve the finished length. The two pieces of stock are identical and can be interchangeable from the fore and aft position.

It is recommended that a Thordon Bearing representative be on-hand should a bearing need to be changed. Replacement/spare material is rough molded (RM), meaning that that it is over and under size. The Inside Diameter (ID) and Outside Diameter (OD) will need to be finished machined. The replacement/spare is offered this way to allow a "skim cut" to be taken on the shaft liner should it be needed.

At that point, the Thordon representative would then machine the bearing to fit the new undersized shaft. Due to the sensitivity to temperature changes during the machining process, it is very important that a Thordon Bearings representative be present for machining. Failure to compensate for temperature differences during the machining process can cause a bearing failure.

SECTION 2

SYSTEM DRAWINGS

SECTION 3 -THORDON COMPAC INFORMATION

P R

O T

ECTING TH

E

E

N V I R O N M

E N

T

COMPAC

WATER LUBRICATED

PROPELLER SHAFT

BEARING SYSTEMS

Bringing Water Lubrication Into the 21st Century

Customer Focused To Support Your Immediate and Future Needs

Visit our web site at http: / /www.thordonbearings.com

3225 Mainway, Burlington, Ontario Canada L7M 1A6 Tel (905) 335-1440 Fax (905) 335-4033

E-mail info@thordonbearings.comCC 04/01/3000 BC Printed in Canada

ISO 9001

CGSB

Registration #93649

Supply and Service: Geared to provide quick response to customer needs, Thordon Bearings understands the importance of quick delivery and reduced down time. Thordon marine bearing systems can be designed, produced to the exact requirements of the customer and shipped quickly.

Distribution: With Thordon bearings specified all around the world, an extensive distribution network has been established in over 50 countries. Inventories of common bearing sizes are stocked by local Thordon Distributors and are backed up by large regional and head office Thordon stocks.

Application Engineering:

Thordon Bearing’s engineers work closely with customers to provide innovative bearing system designs that meet or exceed the technical requirements of the application.

Manufacturing: Thordon’s modern polymer processing facility is staffed with experienced and dedicated employees. Bearings up to 2.2 m (86") in diameter have been supplied and bearings up to 1.2 m (48") O.D. with lengths up to 5.5m (216") have been machined in-house.

Quality: Thordon Bearings Inc. is a Canadian company manufacturing to ISO 9001 Quality System requirements. With over 30 years experience in elastomeric bearing design, application engineering and manufacturing, Thordon marine bearings are recognized worldwide for both quality and performance.

Research and Development: Thordon bearings are being continuously tested by our Bearing Test Facility.

The Facility evaluates new designs and applications before they are put into service.

Ongoing testing not only allows for design refinements, but ensures quality and performance after installation.

Our polymer laboratory evaluates new and modified polymers in a continuing quest to improve Thordon bearing performance and search for new polymer bearing solutions.

Your Local Thordon Distributor

Thordon Represented Worldwide by Over 60 Distributors

Compac Brochure 4/13/01 12:33 PM Page 1

Environmental Pollution Liability in United States Waters

• Any spill or discharge that results in an oil sheen on the navigable waters of the United States must be reported immediately

• Vessel crew members and corporate officers of corporations that own or operate vessels face potential criminal liability for practically any oil spill. This is true even when the spill is small or the resulting environmental damage is minor

• The US Coast Guard is the primary federal enforcement agency

• Between 1992 and 1998, the Environmental Protection Agency (EPA) increased the number of its criminal investigators nearly three-fold (from 72 to 200)

• The US Dept. of Justice has made environmental criminal enforcement of maritime pollution, including vessel-source pollution, a top priority

• The US Coast Guard and EPA officers are authorized to board and inspect any vessel upon the navigable waters of the United States under the Clean Water Act

• Penalties from violations of environmental laws range from fines or jail terms, civil penalties, loss of government contracts, bad public relations and insurance coverage issues

Excerpts from Environmental Criminal Liability in the United States – A Handbook for the Marine

Industry published by the Chamber of Shipping of

America, 2000

Rudokop, a 1958 Russian-built, Thordon-owned steam tug is used as a test platform for R & D, as well as a floating marine showcase where potential clients can see Thordon’s new and existing marine products.

IN THE PAST...

The use of water as a bearing lubricant dates back to the earliest days of shaft driven propellers on ships. Early attempts to use water lubricated babbit bearings failed and designers of the day found that the best bearing solution was lignum vitae, a hard, fine grained wood that usually lasted the four years between dockings. However, as good quality lignum vitae became more difficult to obtain, alternative materials such as phenolic resin and other non-metallic based materials began to be used. The wear life of these products was similar to lignum vitae; satisfactory in clean water but unpredictable and often unacceptable when operating in dirty, abrasive water.

This led to the development of systems in the 1950’s using oil lubricated white metal bearings in a sealed stern tube. Bearing wear rates decreased, especially when operating in dirty abrasive water; the oil was a good fluid on which to develop a hydro-dynamic bearing film and also protected the tailshaft from corrosion. These improvements resulted in extended docking cycles and while stern tube seals were not always reliable, oil leakage or “consumption” was not considered to be a major issue.

Reliability, long wear life and superior customer service have made Thordon Bearings the first choice for pollution free, propeller shaft, rudder and deck equipment bearing solutions for repair, conversion or new build projects.

Thordon Bearings, a pioneer in the development of pollution free bearing designs, offers a choice of either sealed or open, water lubricated propeller shaft bearing systems. The Thor-Lube sealed stern tube system combines proven XL bearings with Thor-lube, a water soluble, non-polluting lubricant. Thordon’s open, water lubricated system choices are COMPAC, XL and Composite; each offering specific advantages in different water environments.

Thordon’s new self-positioning intermediate lineshaft bearing is designed to make installation quick, easy and accurate. Built-in hydraulic levellers make precise setting of the reaction force required to minimize internal stresses in the shaftline straightforward. Since the bearing housing is always parallel to the shaft line, the end seals are always concentric. A series of bearings on a shaftline can be jacked into position simultaneously. As final adjustments are made on each bearing, the effect on the other bearings in the shaftline can be quickly determined and corrected if necessary.

Chocking is not used.

Future re-alignment if required for any reason is simply a matter of re-jacking.

Thordon’s grease free rudder bearing systems are operating smoothly and pollution free on thousands of vessels around the world. Using proven Thordon SXL bearings, the system offers the reliability needed in today’s marine industry and is backed by Thordon’s exclusive 10 year wear life guarantee.

Today, with over 25 years of trouble-free installations documented, Thordon marine bearing systems are the proven, reliable, pollution free solution for ship owners, managers and yards who demand the best.

The Proven Choice For Long Life, Pollution Free

Marine Bearing Systems

Compac Brochure 4/13/01 12:33 PM Page 2

THORDON... A PROVEN

POLLUTION FREE SOLUTION

TODAY’S ENVIRONMENT

In the 21st century, pollution and the preservation of the environment are very important issues for shipowners. The United States has passed the Clean Water Act requiring that any spill or discharge that results in a sheen on the navigable waters in the contiguous zone (24 nautical miles from baseline) of the United States be immediately reported to the U.S. National Response Center. Other countries are also starting to enact their own legislation to protect the marine environment. The U.S. Oil Pollution Act has established a framework for financial liability for costs and damages resulting from even a minor spill. Additionally, potential personal criminal liability for vessel crew members and corporate officers involved in any pollution incident has also been defined. U.S. Coast Guard and EPA (Environmental Protection Agency) investigators are tasked with enforcing the Clean Water Act.

Compared to a mishap involving an oil tanker spill, it may appear that oil leaking from a stern tube would be of minor consequence. However, incidences of vessels being detained and significant fines being assessed resulting directly from stern tube oil leakage are increasing daily.

Shipowners can completely avoid these environmental liability issues by using one of Thordon’s two water-based, pollution free propeller shaft bearing systems. Thor-Lube is a sealed system combining proven non-metallic Thordon XL bearings with Thor-Lube, a non polluting water-based lubricant (a separate brochure for Thor-Lube is available).

Thordon’s COMPAC propeller shaft bearing system is the result of combining 21st century technology and 25 years of bearing experience using the proven principles of water-lubrication. The result, a simple, reliable and totally pollution free stern tube bearing system.

ACQUISITION COSTS

• COMPAC bearings

• Bearing carriers if chocked installation

• Bearing axial keeper rings

• Shaft liners

• Shaft coating

• Water quality package including filtration, piping and alarmed flow sensor

• Forward seal

INSTALLATION COSTS

• Stern tube machining

• Bearing machining-Freeze fit (Straight OD)

• Bearing installation-Freeze fit & install non-metallic bearing

• Align & chock bearing & carrier (if being chocked)

• Install bearing keeper rings

• Install shaft liners

• Install shaft coating and sealing at propeller

• Install water quality package & piping

• Install forward seal

OPERATING COSTS

• Water circulating pump-energy

• Labour to service water quality package filters

REGULAR MAINTENANCE COSTS

• Shaft coating inspection at 5 and 15 year dockings

(may require shaft withdrawal) and reseal at propeller

• Bearing replacement, skimming of shaft liners and renewal of Thor-Coat and reseal of propeller at 10 year docking

• Water supply pump maintenance - repair/replace every 5 years

• Replacement of SeaLion seal carbon wear face & re-lapping of steel stationary face at 5, 10 & 15 year dockings

OTHER COSTS TO CONSIDER

• Favourable publicity can be achieved by promoting “green” water lubricated stern tube.

• Emergency replacement bearing available in one week if required

ACQUISITION COSTS

• White metal bearings

• Bearing carriers if chocked installation

• Anti-rotation key

• Oil head tank(s) & piping

• Seal oil head tank(s) & piping

• Oil drain tank, pump & piping

• Bearing thermocouples & alarm

• Low oil level sensor & alarm

• Forward and aft seals including liners

INSTALLATION COSTS

• Stern tube machining - aft suitable for seal and more critical bearing alignment required

• Bearing machining-interference fit (Stepped OD and flow channels)

• Bearing installation-Rig and press fit metallic bearing

• Align & chock bearing & carrier (if being chocked)

• Install bearing key

• Install thermocouples & alarm

• Install head, drain & seal tanks

• Install all piping

• Install forward and aft seals

• Oil for stern tube & all head tanks

OPERATING COSTS

• Oil to maintain head tank levels

• Friction losses resulting from higher viscosity of oil

(compared to water) at shaft operating speed

• Labour to check and maintain oil levels

• Oil disposal costs when oil renewed

REGULAR MAINTENANCE COSTS

• Seal lip replacement and seal liner re-positioning at 5 and

15 year dockings

• Seal Lip and Lip Seal Liner replacement at 10 year docking

• Oil sampling and analysis costs (if T-Mon)

• Shaft withdrawal & bearing inspection at 15 years if T-Mon & 10 years if not

OTHER COSTS TO CONSIDER

• One emergency docking during operating life of ship to repair damaged aft seal

• Emergency replacement bearing available in 3-6 weeks if required

• Off-hire time resulting from detention of vessel due to stern tube oil leakage

• Fines due to stern tube oil leakage

• Unfavourable publicity resulting from stern tube oil leakage

• Personal liability of crew and corporate officers for damages resulting from stern tube oil leakage

COST OF OWNERSHIP ANALYSIS

Over a 20 year life cycle the following factors must be considered when evaluating the total cost of ownership of a COMPAC stern tube system versus a conventional white metal/oil sealed system.

COMPAC SYSTEM OIL/WHITE METAL SYSTEM

Compac Brochure 4/13/01 12:33 PM Page 3

COMPAC Bearing System The Thordon COMPAC package as supplied by

Thordon Bearings is comprised of the following components:

• Thordon COMPAC water lubricated elastomeric polymer alloy bearings

• Bearing Carriers (depending on the fitting method and design requirements)

• Centrifugally cast bronze alloy shaft liners

• Thor-Coat long life shaft coating

• Integrated water quality package

• Thordon SeaLion-C mechanical face type forward sealing arrangement

Bearing carriers for the bearings are required if the bearings are to be chocked in place, or if the ability to replace the bearings with the shaft in place is desirable.

Borescoping service to monitor the condition of the Thor-Coat shaft coating and the shaft liner in way of the bearings if the bearings are split and have been removed is available from Thordon Bearings.

To ensure shaft voltage buildup does not affect the forward seal or other propulsion machinery, a high quality shaft grounding system is available from Thordon Bearings.

Shaft alignment analysis performed with the shaft in place is also available from Thordon Bearings.

COMPAC STERN TUBE

BEARINGS

Thordon COMPAC bearings are specified as the bearing wear surface. Designed in a special configuration that promotes the development of a hydrodynamic film at lower shaft speeds, COMPAC is manufactured using a low friction, elastomeric polymer alloy. COMPAC bearings are approved to the same specific operating pressure as white metal bearings making conversions to COMPAC straightforward.

To reduce start-up friction and eliminate stick-slip, COMPAC is formulated to provide a low coefficient of friction. To promote early formation of a hydrodynamic film between the shaft and bearing, the lower (loaded) portion of the bearing is smooth, while the upper half of the bearing incorporates water grooves for lubrication and cooling.

Thordon COMPAC bearings are available in either full form tubes or split configuration depending on the design requirements.

Abrasion Resistant Due to its elastomeric properties, Thordon COMPAC bearings tend to deflect and then reject abrasive particles allowing them to be flushed through the bearing without becoming embedded.

Accommodates Edge Loading Edge loading conditions often occur as a result of minor misalignment or shaft and hull deflection.

Approximately 50 times more elastic than white metal, Thordon deflects slightly under edge loading. The load is spread, and the localized pressure on the bearing reduced, eliminating the bearing wiping that often occurs under these conditions. In addition, the chance of damaging a Thordon bearing while installing or withdrawing the shaft is also greatly reduced.

Straightforward Conversions COMPAC is approved to the same specific pressures as white metal making conversion to COMPAC straightforward. The COMPAC bearing can normally be installed in the same space as a white metal bearing, water supply installed and the aft seal removed allowing water flow through the stern tube.

Corrosion and Chemical Resistant Electrically inert, Thordon bearings resist seawater corrosion at both the bearing surface and the interface between the bearing and the housing.

Low Friction Thordon’s static breakaway and dynamic coefficients of friction are both lower than other materials commonly used for water lubricated propeller shaft bearings. To further reduce running friction and improve low speed hydrodynamic film development, the lower half (loaded) portion of the COMPAC bearing is smooth and the upper half is designed with water grooves for lubrication and cooling. At rated shaft speeds, drag on the rotating shaft resulting from the viscosity of the lubricating fluid is lower with water than with oil resulting in potential fuel savings.

Extensive References Thordon COMPAC bearing systems have been specified for years in Naval and Coast Guard applications. More recently, commercial ship owners and managers, including major cruise ship operators, have specified Thordon COMPAC for its pollution free simplicity and reliability. A Thordon COMPAC reference list is available.

C O

E F

F

IC

IE

N

T O

F F

R

IC

T

IO

N

SHAFT RPM

OIL

WATER

Crossover Friction Curve – Water vs. Oil

THORDON COMPAC

TYPICAL NON-METALLIC

LEAD BASED WHITE METAL

CONTACT LENGTH

C

IR

C U

M F

E R

E N

T

IA

L C

O N

TA

C

T

Typical Edge Loading Profile

Projected Bearing Wear by Volume (Independent Testing at University of Cincinnati, USA)

0.01 0.05 0.1 0.5 1 5 10 50 100

Brass

Cotton Phenolic

Virgin Teflon

Acetyl

Lignum Vitae

Asbestos Phenolic

Nylon 612

Thordon XL

Thordon SXL/COMPAC

Rubber

Thordon Composite

Typical Bearing Abrasive Wear Rates

Compac Brochure 4/13/01 12:33 PM Page 4

SHAFT COATING

In a COMPAC open system, seawater is used as the lubricant and the shaft must be protected from corrosion.

Shaft coatings used to protect the shaftline in the past have been an “Achilles heel” of open systems. Currently, the shaft must be withdrawn and the coating inspected every 5 years because the coatings used are typically fiberglass/epoxy based and susceptible to cracking. To address this issue, Thordon’s polymer R&D lab has developed Thor-Coat, a toughened, modified epoxy coating designed to provide 10 year integrity eliminating the need for the 5 year shaft withdrawal and inspection.

Thor-Coat currently has provisional approval and Thordon is working closely with the Classification Societies to develop approval for in-situ inspections at the 5-year dockings.

COMPAC

WATER LUBRICATED PROPELLER SHAFT

BEARING SYSTEM

Offers These Proven Owner Benefits Pollution Free The Thordon COMPAC open propeller shaft bearing system eliminates the use of oil offering zero pollution.

As global environmental awareness and the enactment of legislation to protect the marine environment increases, Thordon’s COMPAC system eliminates port fines, delays, bad publicity and potential criminal liability that can result from any oil spill, however small.

Long, Predictable Wear Life With over 25 years of hydrodynamic bearing experience, Thordon’s COMPAC bearing system has been designed to reach the 10 year docking cycle or beyond in blue water operation, before replacement is necessary.

Full Classification Approvals Thordon COMPAC bearings are approved by all major

Classification Societies. Water-lubricated COMPAC is approved to the same operating pressures as white metal bearings.

Reduced Time in Dock If specified, Thordon COMPAC’s unique single tapered key bearing design allows inspection or renewal of the bearings with the shaft in place. Originally developed for Disney Cruise Lines, the split bearing design allows the bearings to be withdrawn, inspected and re-installed in a matter of hours.

High Resilience/Impact Resistance Elastomeric Thordon bearings tend to absorb impact loads and cushion the shaftline from shock, making them much more resistant to damage from pounding during operation in heavy seas.

Easily Machined and Fitted Thordon COMPAC is asbestos-free, machines cleanly and produces no nuisance dust. COMPAC is much lighter than white metal bearings and can be fitted quickly and easily by freezing in liquid nitrogen.

BEARING CARRIERS

There are several bearing carrier options for Thordon

COMPAC bearings depending on the installation and alignment technique that is being used.

If the stern tube is being bored to ensure alignment, full form COMPAC tubes can be interference fit directly into the stern tube. Conversely, the COMPAC bearings can also be installed and then line bored after installation.

If the bearings are to be aligned individually and chocked in position, they must be installed in a metal carrier. Depending on the importance of being able to remove the bearings with the shaft still in place, several options are available.

Full form bearings can be interference fit into a solid metal carrier or separate inner stern tube and then chocked into position.

Split bearings can be interference fit into a unique Thordon tapered key design one piece housing and chocked into position. Thordon’s split tapered key design, while more expensive than using a full form bearing option, has many practical advantages in service, particularly in the aft bearing position.

SHAFT LINERS

Since bearing “clearance” is the sum of both bearing wear, and wear of the shaft liner, a high quality centrifugally cast shaft liner is an important component of a COMPAC system. Thordon Bearings has developed a bronze alloy formulation for shaft sleeves specifically designed to provide optimum wear performance in combination with Thordon COMPAC bearings.

Compac Brochure 4/13/01 12:34 PM Page 5

COMPAC Open Water Lubricated Bearing System

Shaft Liner

SeaLion-C Forward Seal

Static Emergency

Seal

Stern Tube and Seal

Water Supply from Thordon Water Quality

Package

COMPAC

Bearing

Thor-Coat

WATER QUALITY PACKAGE

A steady supply of relatively abrasive free water is an important element in ensuring long, predictable, bearing wear life. With this factor in mind, Thordon has developed a filtration and monitoring package to ensure that a supply of filtered water is being delivered to both the forward seal and the bearings. The base package consists of 2 filters with 100-micron filtration, automatic switching and alarm if one filter becomes restricted and a flow alarm to identify if water flow to the bearings has been reduced to a critically low level. Water is supplied from the ship’s seawater supply system assuming flow and pressure are adequate. The water supplied must be as cool as possible and not sourced from the engine room or other pre-heat areas. In the event that the ship’s water supply is not suitable, a second package including 2 pumps with automatic switching in the case of pump failure is available.

The recommended flow of water through the bearings is 0.15 litres/minute/mm (1 U.S. gallon / minute / inch) of shaft diameter. In the case of larger shafts (greater than 500 mm (20”) diameter), these volumes can be reduced somewhat.

SEALION-C FORWARD SEAL

Specifically designed for operation in a water lubricated system, Thordon SeaLion-C mechanical seals feature a rotating carbon-graphite face running against a stationary chromium alloy mating face providing positive sealing in a simple rugged design. SeaLion-C ‘s outside pressurized design and self-cleaning action ensures minimal leakage and low maintenance.

A standard static maintenance seal avoids costly drydocking if emergency seal repairs are required.

Worn, rotating carbon-graphite seal faces can be quickly and easily replaced using Thordon’s split seal repair kit. A separate brochure fully detailing the advantages of Thordon SeaLion seals is available.

BORESCOPING SERVICE

To monitor the condition of the shaft line coating and the shaft liner without withdrawing the shaft, Thordon Bearings has developed borescoping technology allowing a probe to be inserted into the stern tube along the 12 o’clock bearing lubrication groove.

The shaft liner and shaft coating can be viewed, and the images recorded on tape for future reference, by positioning the camera as appropriate and rotating the shaft. With access to the lubrication grooves on the aft bearing, this inspection can also be performed underwater.

SHAFT ALIGNMENT

ANALYSIS

Shaft alignment analysis can be performed with the shaft in place using strain gauges to define the baseline alignment profile of a new ship after launch. Subsequently, follow-up analysis to monitor and easily identify alignment issues resulting from the effect of changes through the operating life of the ship can be done quickly and easily.

Compac Brochure 4/13/01 12:34 PM Page 6

COMPAC Open Water Lubricated Bearing System

Shaft Liner

SeaLion-C Forward Seal

Static Emergency

Seal

Stern Tube and Seal

Water Supply from Thordon Water Quality

Package

COMPAC

Bearing

Thor-Coat

WATER QUALITY PACKAGE

A steady supply of relatively abrasive free water is an important element in ensuring long, predictable, bearing wear life. With this factor in mind, Thordon has developed a filtration and monitoring package to ensure that a supply of filtered water is being delivered to both the forward seal and the bearings. The base package consists of 2 filters with 100-micron filtration, automatic switching and alarm if one filter becomes restricted and a flow alarm to identify if water flow to the bearings has been reduced to a critically low level. Water is supplied from the ship’s seawater supply system assuming flow and pressure are adequate. The water supplied must be as cool as possible and not sourced from the engine room or other pre-heat areas. In the event that the ship’s water supply is not suitable, a second package including 2 pumps with automatic switching in the case of pump failure is available.

The recommended flow of water through the bearings is 0.15 litres/minute/mm (1 U.S. gallon / minute / inch) of shaft diameter. In the case of larger shafts (greater than 500 mm (20”) diameter), these volumes can be reduced somewhat.

SEALION-C FORWARD SEAL

Specifically designed for operation in a water lubricated system, Thordon SeaLion-C mechanical seals feature a rotating carbon-graphite face running against a stationary chromium alloy mating face providing positive sealing in a simple rugged design. SeaLion-C ‘s outside pressurized design and self-cleaning action ensures minimal leakage and low maintenance.

A standard static maintenance seal avoids costly drydocking if emergency seal repairs are required.

Worn, rotating carbon-graphite seal faces can be quickly and easily replaced using Thordon’s split seal repair kit. A separate brochure fully detailing the advantages of Thordon SeaLion seals is available.

BORESCOPING SERVICE

To monitor the condition of the shaft line coating and the shaft liner without withdrawing the shaft, Thordon Bearings has developed borescoping technology allowing a probe to be inserted into the stern tube along the 12 o’clock bearing lubrication groove.

The shaft liner and shaft coating can be viewed, and the images recorded on tape for future reference, by positioning the camera as appropriate and rotating the shaft. With access to the lubrication grooves on the aft bearing, this inspection can also be performed underwater.

SHAFT ALIGNMENT

ANALYSIS

Shaft alignment analysis can be performed with the shaft in place using strain gauges to define the baseline alignment profile of a new ship after launch. Subsequently, follow-up analysis to monitor and easily identify alignment issues resulting from the effect of changes through the operating life of the ship can be done quickly and easily.

Compac Brochure 4/13/01 12:34 PM Page 6

SHAFT COATING

In a COMPAC open system, seawater is used as the lubricant and the shaft must be protected from corrosion.

Shaft coatings used to protect the shaftline in the past have been an “Achilles heel” of open systems. Currently, the shaft must be withdrawn and the coating inspected every 5 years because the coatings used are typically fiberglass/epoxy based and susceptible to cracking. To address this issue, Thordon’s polymer R&D lab has developed Thor-Coat, a toughened, modified epoxy coating designed to provide 10 year integrity eliminating the need for the 5 year shaft withdrawal and inspection.

Thor-Coat currently has provisional approval and Thordon is working closely with the Classification Societies to develop approval for in-situ inspections at the 5-year dockings.

COMPAC

WATER LUBRICATED PROPELLER SHAFT

BEARING SYSTEM

Offers These Proven Owner Benefits Pollution Free The Thordon COMPAC open propeller shaft bearing system eliminates the use of oil offering zero pollution.

As global environmental awareness and the enactment of legislation to protect the marine environment increases, Thordon’s COMPAC system eliminates port fines, delays, bad publicity and potential criminal liability that can result from any oil spill, however small.

Long, Predictable Wear Life With over 25 years of hydrodynamic bearing experience, Thordon’s COMPAC bearing system has been designed to reach the 10 year docking cycle or beyond in blue water operation, before replacement is necessary.

Full Classification Approvals Thordon COMPAC bearings are approved by all major

Classification Societies. Water-lubricated COMPAC is approved to the same operating pressures as white metal bearings.

Reduced Time in Dock If specified, Thordon COMPAC’s unique single tapered key bearing design allows inspection or renewal of the bearings with the shaft in place. Originally developed for Disney Cruise Lines, the split bearing design allows the bearings to be withdrawn, inspected and re-installed in a matter of hours.

High Resilience/Impact Resistance Elastomeric Thordon bearings tend to absorb impact loads and cushion the shaftline from shock, making them much more resistant to damage from pounding during operation in heavy seas.

Easily Machined and Fitted Thordon COMPAC is asbestos-free, machines cleanly and produces no nuisance dust. COMPAC is much lighter than white metal bearings and can be fitted quickly and easily by freezing in liquid nitrogen.

BEARING CARRIERS

There are several bearing carrier options for Thordon

COMPAC bearings depending on the installation and alignment technique that is being used.

If the stern tube is being bored to ensure alignment, full form COMPAC tubes can be interference fit directly into the stern tube. Conversely, the COMPAC bearings can also be installed and then line bored after installation.

If the bearings are to be aligned individually and chocked in position, they must be installed in a metal carrier. Depending on the importance of being able to remove the bearings with the shaft still in place, several options are available.

Full form bearings can be interference fit into a solid metal carrier or separate inner stern tube and then chocked into position.

Split bearings can be interference fit into a unique Thordon tapered key design one piece housing and chocked into position. Thordon’s split tapered key design, while more expensive than using a full form bearing option, has many practical advantages in service, particularly in the aft bearing position.

SHAFT LINERS

Since bearing “clearance” is the sum of both bearing wear, and wear of the shaft liner, a high quality centrifugally cast shaft liner is an important component of a COMPAC system. Thordon Bearings has developed a bronze alloy formulation for shaft sleeves specifically designed to provide optimum wear performance in combination with Thordon COMPAC bearings.

Compac Brochure 4/13/01 12:34 PM Page 5

COMPAC Bearing System The Thordon COMPAC package as supplied by

Thordon Bearings is comprised of the following components:

• Thordon COMPAC water lubricated elastomeric polymer alloy bearings

• Bearing Carriers (depending on the fitting method and design requirements)

• Centrifugally cast bronze alloy shaft liners

• Thor-Coat long life shaft coating

• Integrated water quality package

• Thordon SeaLion-C mechanical face type forward sealing arrangement

Bearing carriers for the bearings are required if the bearings are to be chocked in place, or if the ability to replace the bearings with the shaft in place is desirable.

Borescoping service to monitor the condition of the Thor-Coat shaft coating and the shaft liner in way of the bearings if the bearings are split and have been removed is available from Thordon Bearings.

To ensure shaft voltage buildup does not affect the forward seal or other propulsion machinery, a high quality shaft grounding system is available from Thordon Bearings.

Shaft alignment analysis performed with the shaft in place is also available from Thordon Bearings.

COMPAC STERN TUBE

BEARINGS

Thordon COMPAC bearings are specified as the bearing wear surface. Designed in a special configuration that promotes the development of a hydrodynamic film at lower shaft speeds, COMPAC is manufactured using a low friction, elastomeric polymer alloy. COMPAC bearings are approved to the same specific operating pressure as white metal bearings making conversions to COMPAC straightforward.

To reduce start-up friction and eliminate stick-slip, COMPAC is formulated to provide a low coefficient of friction. To promote early formation of a hydrodynamic film between the shaft and bearing, the lower (loaded) portion of the bearing is smooth, while the upper half of the bearing incorporates water grooves for lubrication and cooling.

Thordon COMPAC bearings are available in either full form tubes or split configuration depending on the design requirements.

Abrasion Resistant Due to its elastomeric properties, Thordon COMPAC bearings tend to deflect and then reject abrasive particles allowing them to be flushed through the bearing without becoming embedded.

Accommodates Edge Loading Edge loading conditions often occur as a result of minor misalignment or shaft and hull deflection.

Approximately 50 times more elastic than white metal, Thordon deflects slightly under edge loading. The load is spread, and the localized pressure on the bearing reduced, eliminating the bearing wiping that often occurs under these conditions. In addition, the chance of damaging a Thordon bearing while installing or withdrawing the shaft is also greatly reduced.

Straightforward Conversions COMPAC is approved to the same specific pressures as white metal making conversion to COMPAC straightforward. The COMPAC bearing can normally be installed in the same space as a white metal bearing, water supply installed and the aft seal removed allowing water flow through the stern tube.

Corrosion and Chemical Resistant Electrically inert, Thordon bearings resist seawater corrosion at both the bearing surface and the interface between the bearing and the housing.

Low Friction Thordon’s static breakaway and dynamic coefficients of friction are both lower than other materials commonly used for water lubricated propeller shaft bearings. To further reduce running friction and improve low speed hydrodynamic film development, the lower half (loaded) portion of the COMPAC bearing is smooth and the upper half is designed with water grooves for lubrication and cooling. At rated shaft speeds, drag on the rotating shaft resulting from the viscosity of the lubricating fluid is lower with water than with oil resulting in potential fuel savings.

Extensive References Thordon COMPAC bearing systems have been specified for years in Naval and Coast Guard applications. More recently, commercial ship owners and managers, including major cruise ship operators, have specified Thordon COMPAC for its pollution free simplicity and reliability. A Thordon COMPAC reference list is available.

C O

E F

F

IC

IE

N

T O

F F

R

IC

T

IO

N

SHAFT RPM

OIL

WATER

Crossover Friction Curve – Water vs. Oil

THORDON COMPAC

TYPICAL NON-METALLIC

LEAD BASED WHITE METAL

CONTACT LENGTH

C

IR

C U

M F

E R

E N

T

IA

L C

O N

TA

C

T

Typical Edge Loading Profile

Projected Bearing Wear by Volume (Independent Testing at University of Cincinnati, USA)

0.01 0.05 0.1 0.5 1 5 10 50 100

Brass

Cotton Phenolic

Virgin Teflon

Acetyl

Lignum Vitae

Asbestos Phenolic

Nylon 612

Thordon XL

Thordon SXL/COMPAC

Rubber

Thordon Composite

Typical Bearing Abrasive Wear Rates

Compac Brochure 4/13/01 12:33 PM Page 4

THORDON... A PROVEN

POLLUTION FREE SOLUTION

TODAY’S ENVIRONMENT

In the 21st century, pollution and the preservation of the environment are very important issues for shipowners. The United States has passed the Clean Water Act requiring that any spill or discharge that results in a sheen on the navigable waters in the contiguous zone (24 nautical miles from baseline) of the United States be immediately reported to the U.S. National Response Center. Other countries are also starting to enact their own legislation to protect the marine environment. The U.S. Oil Pollution Act has established a framework for financial liability for costs and damages resulting from even a minor spill. Additionally, potential personal criminal liability for vessel crew members and corporate officers involved in any pollution incident has also been defined. U.S. Coast Guard and EPA (Environmental Protection Agency) investigators are tasked with enforcing the Clean Water Act.

Compared to a mishap involving an oil tanker spill, it may appear that oil leaking from a stern tube would be of minor consequence. However, incidences of vessels being detained and significant fines being assessed resulting directly from stern tube oil leakage are increasing daily.

Shipowners can completely avoid these environmental liability issues by using one of Thordon’s two water-based, pollution free propeller shaft bearing systems. Thor-Lube is a sealed system combining proven non-metallic Thordon XL bearings with Thor-Lube, a non polluting water-based lubricant (a separate brochure for Thor-Lube is available).

Thordon’s COMPAC propeller shaft bearing system is the result of combining 21st century technology and 25 years of bearing experience using the proven principles of water-lubrication. The result, a simple, reliable and totally pollution free stern tube bearing system.

ACQUISITION COSTS

• COMPAC bearings

• Bearing carriers if chocked installation

• Bearing axial keeper rings

• Shaft liners

• Shaft coating

• Water quality package including filtration, piping and alarmed flow sensor

• Forward seal

INSTALLATION COSTS

• Stern tube machining

• Bearing machining-Freeze fit (Straight OD)

• Bearing installation-Freeze fit & install non-metallic bearing

• Align & chock bearing & carrier (if being chocked)

• Install bearing keeper rings

• Install shaft liners

• Install shaft coating and sealing at propeller

• Install water quality package & piping

• Install forward seal

OPERATING COSTS

• Water circulating pump-energy

• Labour to service water quality package filters

REGULAR MAINTENANCE COSTS

• Shaft coating inspection at 5 and 15 year dockings

(may require shaft withdrawal) and reseal at propeller

• Bearing replacement, skimming of shaft liners and renewal of Thor-Coat and reseal of propeller at 10 year docking

• Water supply pump maintenance - repair/replace every 5 years

• Replacement of SeaLion seal carbon wear face & re-lapping of steel stationary face at 5, 10 & 15 year dockings

OTHER COSTS TO CONSIDER

• Favourable publicity can be achieved by promoting “green” water lubricated stern tube.

• Emergency replacement bearing available in one week if required

ACQUISITION COSTS

• White metal bearings

• Bearing carriers if chocked installation

• Anti-rotation key

• Oil head tank(s) & piping

• Seal oil head tank(s) & piping

• Oil drain tank, pump & piping

• Bearing thermocouples & alarm

• Low oil level sensor & alarm

• Forward and aft seals including liners

INSTALLATION COSTS

• Stern tube machining - aft suitable for seal and more critical bearing alignment required

• Bearing machining-interference fit (Stepped OD and flow channels)

• Bearing installation-Rig and press fit metallic bearing

• Align & chock bearing & carrier (if being chocked)

• Install bearing key

• Install thermocouples & alarm

• Install head, drain & seal tanks

• Install all piping

• Install forward and aft seals

• Oil for stern tube & all head tanks

OPERATING COSTS

• Oil to maintain head tank levels

• Friction losses resulting from higher viscosity of oil

(compared to water) at shaft operating speed

• Labour to check and maintain oil levels

• Oil disposal costs when oil renewed

REGULAR MAINTENANCE COSTS

• Seal lip replacement and seal liner re-positioning at 5 and

15 year dockings

• Seal Lip and Lip Seal Liner replacement at 10 year docking

• Oil sampling and analysis costs (if T-Mon)

• Shaft withdrawal & bearing inspection at 15 years if T-Mon & 10 years if not

OTHER COSTS TO CONSIDER

• One emergency docking during operating life of ship to repair damaged aft seal

• Emergency replacement bearing available in 3-6 weeks if required

• Off-hire time resulting from detention of vessel due to stern tube oil leakage

• Fines due to stern tube oil leakage

• Unfavourable publicity resulting from stern tube oil leakage

• Personal liability of crew and corporate officers for damages resulting from stern tube oil leakage

COST OF OWNERSHIP ANALYSIS

Over a 20 year life cycle the following factors must be considered when evaluating the total cost of ownership of a COMPAC stern tube system versus a conventional white metal/oil sealed system.

COMPAC SYSTEM OIL/WHITE METAL SYSTEM

Compac Brochure 4/13/01 12:33 PM Page 3

Environmental Pollution Liability in United States Waters

• Any spill or discharge that results in an oil sheen on the navigable waters of the United States must be reported immediately

• Vessel crew members and corporate officers of corporations that own or operate vessels face potential criminal liability for practically any oil spill. This is true even when the spill is small or the resulting environmental damage is minor

• The US Coast Guard is the primary federal enforcement agency

• Between 1992 and 1998, the Environmental Protection Agency (EPA) increased the number of its criminal investigators nearly three-fold (from 72 to 200)

• The US Dept. of Justice has made environmental criminal enforcement of maritime pollution, including vessel-source pollution, a top priority

• The US Coast Guard and EPA officers are authorized to board and inspect any vessel upon the navigable waters of the United States under the Clean Water Act

• Penalties from violations of environmental laws range from fines or jail terms, civil penalties, loss of government contracts, bad public relations and insurance coverage issues

Excerpts from Environmental Criminal Liability in the United States – A Handbook for the Marine

Industry published by the Chamber of Shipping of

America, 2000

Rudokop, a 1958 Russian-built, Thordon-owned steam tug is used as a test platform for R & D, as well as a floating marine showcase where potential clients can see Thordon’s new and existing marine products.

IN THE PAST...

The use of water as a bearing lubricant dates back to the earliest days of shaft driven propellers on ships. Early attempts to use water lubricated babbit bearings failed and designers of the day found that the best bearing solution was lignum vitae, a hard, fine grained wood that usually lasted the four years between dockings. However, as good quality lignum vitae became more difficult to obtain, alternative materials such as phenolic resin and other non-metallic based materials began to be used. The wear life of these products was similar to lignum vitae; satisfactory in clean water but unpredictable and often unacceptable when operating in dirty, abrasive water.

This led to the development of systems in the 1950’s using oil lubricated white metal bearings in a sealed stern tube. Bearing wear rates decreased, especially when operating in dirty abrasive water; the oil was a good fluid on which to develop a hydro-dynamic bearing film and also protected the tailshaft from corrosion. These improvements resulted in extended docking cycles and while stern tube seals were not always reliable, oil leakage or “consumption” was not considered to be a major issue.

Reliability, long wear life and superior customer service have made Thordon Bearings the first choice for pollution free, propeller shaft, rudder and deck equipment bearing solutions for repair, conversion or new build projects.

Thordon Bearings, a pioneer in the development of pollution free bearing designs, offers a choice of either sealed or open, water lubricated propeller shaft bearing systems. The Thor-Lube sealed stern tube system combines proven XL bearings with Thor-lube, a water soluble, non-polluting lubricant. Thordon’s open, water lubricated system choices are COMPAC, XL and Composite; each offering specific advantages in different water environments.

Thordon’s new self-positioning intermediate lineshaft bearing is designed to make installation quick, easy and accurate. Built-in hydraulic levellers make precise setting of the reaction force required to minimize internal stresses in the shaftline straightforward. Since the bearing housing is always parallel to the shaft line, the end seals are always concentric. A series of bearings on a shaftline can be jacked into position simultaneously. As final adjustments are made on each bearing, the effect on the other bearings in the shaftline can be quickly determined and corrected if necessary.

Chocking is not used.

Future re-alignment if required for any reason is simply a matter of re-jacking.

Thordon’s grease free rudder bearing systems are operating smoothly and pollution free on thousands of vessels around the world. Using proven Thordon SXL bearings, the system offers the reliability needed in today’s marine industry and is backed by Thordon’s exclusive 10 year wear life guarantee.

Today, with over 25 years of trouble-free installations documented, Thordon marine bearing systems are the proven, reliable, pollution free solution for ship owners, managers and yards who demand the best.

The Proven Choice For Long Life, Pollution Free

Marine Bearing Systems

Compac Brochure 4/13/01 12:33 PM Page 2

P R

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T

ECTING TH

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E

N V I R O N M

E N

T

COMPAC

WATER LUBRICATED

PROPELLER SHAFT

BEARING SYSTEMS

Bringing Water Lubrication Into the 21st Century

Customer Focused To Support Your Immediate and Future Needs

Visit our web site at http: / /www.thordonbearings.com

3225 Mainway, Burlington, Ontario Canada L7M 1A6 Tel (905) 335-1440 Fax (905) 335-4033

E-mail info@thordonbearings.comCC 04/01/3000 BC Printed in Canada

ISO 9001

CGSB

Registration #93649

Supply and Service: Geared to provide quick response to customer needs, Thordon Bearings understands the importance of quick delivery and reduced down time. Thordon marine bearing systems can be designed, produced to the exact requirements of the customer and shipped quickly.

Distribution: With Thordon bearings specified all around the world, an extensive distribution network has been established in over 50 countries. Inventories of common bearing sizes are stocked by local Thordon Distributors and are backed up by large regional and head office Thordon stocks.

Application Engineering:

Thordon Bearing’s engineers work closely with customers to provide innovative bearing system designs that meet or exceed the technical requirements of the application.

Manufacturing: Thordon’s modern polymer processing facility is staffed with experienced and dedicated employees. Bearings up to 2.2 m (86") in diameter have been supplied and bearings up to 1.2 m (48") O.D. with lengths up to 5.5m (216") have been machined in-house.

Quality: Thordon Bearings Inc. is a Canadian company manufacturing to ISO 9001 Quality…