ABS_Rules,_Part_7,_Chapter_5,_Sections_1_and_2.pdf

P A R T C h a p t e r 5 : T a i l s h a f t S u r v e y s

C H A P T E R 5 Tailshaft Surveys

CONTENTS

SECTION 1 Survey Requirements

1 General 3 Definitions

3.1 Shaft

3.3 Propeller Shaft

3.5 Tube Shaft

3.7 Stern Tube

3.9 Closed Loop (System) Oil Lubricating Bearing

3.11 Water Lubricated Bearing

3.13 Closed Loop System Fresh Water Lubricated Bearing

3.15 Open Systems (Water)

3.17 Adequate Means for Protection Against Corrosion

3.19 Corrosion Resistant Shaft

3.21 Stern Tube Sealing System

3.23 Service Records

3.25 Oil Sample Examination

3.27 Lubricating Oil Analysis

3.29 Fresh Water Sample Test

3.31 Keyless Connection

3.33 Keyed Connection

3.35 Flanged Connection

3.37 Alternative Means

5 Oil Lubricated Shafts or Closed Loop System Fresh Water Lubricated Shafts (Closed System)

5.1 Shaft Survey Methods

5.3 Shaft Extension Surveys – Extension Types

7 Water Lubricated Shafts (Open Systems)

7.1 Shaft Survey Methods

7.3 Shaft Extension Surveys – Extension Types

9 Vessels in Great Lakes Service

9.1 Tailshaft Survey

SECTION 2 Allowable Bearing Weardown

1 Vessels for Unrestricted Service and in Rivers and Intracoastal Waterways Services

1.1 Water-Lubricated Bearing Other than Rubber

1.3 Water-Lubricated Rubber Bearing

1.5 Oil-Lubricated Bearings

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3 Vessels in Great Lakes Service

3.1 Water-Lubricated Bearings Other than Rubber

3.3 Rubber and Oil-Lubricated Bearings

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P A R T S e c t i o n 1 : S u r v e y R e q u i r e m e n t s

C H A P T E R 5 Tailshaft Surveys

S E C T I O N 1 Survey Requirements

1 General (2016) The following Methods are to be adhered to when conducting Tailshaft Surveys

3 Definitions (2016)

3.1 Shaft

For the purposes of this requirement the shaft definition includes:

• Propeller Shaft

• Tube Shaft

3.3 Propeller Shaft

Propeller Shaft is the part of the propulsion shaft to which the propeller is fitted. It may also be the screw shaft or tailshaft.

3.5 Tube Shaft

Tube shaft is a shaft placed between the intermediate shaft and propeller shaft, normally arranged with the stern tube or running in open water. It may also be called the Stern Tube Shaft.

3.7 Stern Tube

Tube or pipe fitted in the shell of a ship at the stern (or rear part of the ship), below the water-line, through which passes the tube shaft or aftermost section of the propeller shaft. The stern tube is the housing of the shaft bearings, generally two (one aft and one fore), that sustain the shaft and allows its rotation with less frictional resistance. The stern tube also accommodates the shaft sealing arrangements.

3.9 Closed Loop (System) Oil Lubricating Bearing

Closed loop oil lubricating systems use oil to lubricate the bearings and are sealed against the environment (seawater) by adequate sealing/gland devices.

3.11 Water Lubricated Bearing

Water lubricated bearings are bearings cooled/lubricated by water (fresh or salt).

3.13 Closed Loop System Fresh Water Lubricated Bearing

Closed loop water lubricating systems use fresh water to lubricate the bearings and are sealed against the environment (such as seawater) by adequate sealing/gland devices.

3.15 Open Systems (Water)

Open water lubricating systems use water to lubricate the bearings and are exposed to the environment.

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Part 7 Rules for Survey After Construction Chapter 5 Tailshaft Surveys Section 1 Survey Requirements 7-5-1

3.17 Adequate Means for Protection Against Corrosion

An adequate means for protection against corrosion is an approved means for full protection of the core shaft against sea water intrusion and subsequent corrosion attack. Such means are used for the protection of common steel material against corrosion particularly in combination with water lubricated bearings.

Typical examples are:

• Continuous metallic, corrosion resistant liners

• Continuous cladding per 4-3-2/5.17.5

• Multiple layer synthetic coating

• Multiple layers of fiberglass per 4-3-2/5.17.4

• Combinations of the above mentioned

• Rubber/elastomer covering coating

3.19 Corrosion Resistant Shaft

A corrosion resistant shaft is made in approved corrosion resistant steel as core material for the shaft

3.21 Stern Tube Sealing System

Stern tube Sealing System is the equipment installed on the inboard extremity and, for closed systems, at the outboard extremity of the stern tube. The inboard seal is the device fitted on the fore part of the stern tube that achieve the sealing against the possible leakage of the lubricant media. The outboard seal is the device fitted on the aft part of the stern tube that achieve the sealing against the possible sea water ingress and the leakage of the lubricant media.

3.23 Service Records

Service Records are regularly recorded data showing in-service conditions of the shaft(s) and may include, as applicable; lubricating oil temperature, bearing temperature and oil consumption records (for oil lubricated bearings) or water flow, water temperature, salinity, pH, make-up water and water pressure (for closed loop fresh water lubricated bearings depending on design).

3.25 Oil Sample Examination

An oil sample examination is a visual examination of the stern tube lubricating oil taken in the presence of the surveyor with a focus on water contamination.

3.27 Lubricating Oil Analysis

Lubricating oil analysis is to be carried out at regular intervals not exceeding six (6) months. The documentation on lubricating oil analysis is to be available on board. Oil samples submitted for analysis should be taken under service condition

3.29 Fresh Water Sample Test

Fresh water sample test should be carried out at regular intervals not exceeding six (6) months. Samples are to be taken under service conditions and are to be representative of the water circulating within the stern tube. Analysis results are to be retained on board and made available to the surveyor. At the time of survey the sample for the test must be taken in the presence of the Surveyor.

Fresh water sample tests shall include the following parameters:

• Chlorides content

• pH value

• Presence of bearing particles or other particles (only for laboratory analysis, not required for tests carried out in the presence of the Surveyor).

140 ABS RULES FOR SURVEY AFTER CONSTRUCTION . 2016

3.31 Keyless Connection

The keyless connection is the forced coupling methodology between the shaft and the propeller without a key achieved through interference fit of the propeller boss on the shaft tapered end.

3.33 Keyed Connection

The keyed connection is the forced coupling methodology between the shaft and the propeller with a key and a keyway achieved through the interference fit of the propeller boss on the shaft tapered end.

3.35 Flanged Connection

The flanged connection is the coupling methodology, between the shaft and the propeller, achieved by a flange, built in at the shaft end, bolted to the propeller boss.

3.37 Alternative Means

Alternative means are shafting arrangements with configuration other than described in the present document.

5 Oil Lubricated Shafts or Closed Loop System Fresh Water Lubricated Shafts (Closed System) (2016) When the propeller is removed for any reason, the propeller hub is to be examined by a surface crack detection method after reinstallation. Controllable-pitch propellers are to be surveyed along with the tailshaft. The propeller is to be function tested, examined for blade seal leaks, and opened out as deemed necessary by the attending Surveyor.

5.1 Shaft Survey Methods

5.1.1 Method 1

The survey is to consist of:

• Drawing the shaft and examining the entire shaft, seals system and bearings

• For keyed and keyless connections:

- Removing the propeller to expose the forward end of the taper,

- Performing a nondestructive examination (NDE) by a surface crack detection method all around the shaft in way of the forward portion of the taper section, including the keyway (if fitted). For shaft provided with liners, the NDE shall extended to the after edge of the liner.

• For flanged connection:

- Whenever the coupling bolts of any type of flange-connected shaft are removed or the flange radius is made accessible in connection with overhaul, repairs, or when deemed necessary by the Surveyor, the coupling bolts and flange radius are to be examined by means of an approved surface crack detection method.

• Checking and recording the bearing clearances.

• Verification that the propeller is free of damages which may cause the propeller to be out of balance.

• Bearing inboard seal assemblies are to be externally examined and to be found or placed in a satisfactory condition.

• Bearing outboard seals are to be renewed and the seal liner found to be or placed in a satisfactory condition.

• Recording the bearing weardown measurements (after re-installation)

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5.1.2 Method 2

The survey is to consist of:

• For keyed and keyless connections:

- Removing the propeller to expose the forward end of the taper,

- Performing a nondestructive examination (NDE) by a surface crack detection method all around the shaft in way of the forward portion of the taper section, including the keyway (if fitted).

• For flanged connection:

- Whenever the coupling bolts of any type of flange-connected shaft are removed or the flange radius is made accessible in connection with overhaul, repairs, or when deemed necessary by the Surveyor, the coupling bolts and flange radius are to be examined by means of a an approved surface crack detection method.

• Checking and recording the bearing weardown measurements.

• Visual Inspection of all accessible parts of the shafting system.

• Verification that the propeller is free of damages which may cause the propeller to be out of balance.

• Seal liner found to be or placed in a satisfactory condition.

• Bearing inboard seal assemblies are to be externally examined and to be found or placed in a satisfactory condition.

• Bearing outboard seals are to be renewed and the seal liner found to be or placed in a satisfactory condition.

• Review of service records.

• Review of test records of:

- Lubricating Oil analysis (for oil lubricated shafts), or

- Fresh Water Sample test (for closed system fresh water lubricated shafts).

• Oil Sample Examination (for oil lubricated shafts), or Fresh Water Sample test (for closed system fresh water lubricated).

• Verification of no reported repairs by grinding or welding of shaft and/or propeller.

5.1.3 Method 3

The survey is to consist of:

• Checking and recording the bearing weardown measurements.

• Visual Inspection of all accessible parts of the shafting system. Verification that the propeller is free of damages which may cause the propeller to be out of balance.

• Seal liner found to be or placed in a satisfactory condition.

• Verification of the satisfactory conditions of inboard and outboard seals.

• Review of service records.

• Review of test records of:

- Lubricating Oil analysis (for oil lubricated shafts), or

- Fresh Water Sample test (for closed system fresh water lubricated shafts).

• Oil Sample Examination (for oil lubricated shafts), or Fresh Water Sample test (for closed system fresh water lubricated).

• Verification of no reported repairs by grinding or welding of shaft and/or propeller.

142 ABS RULES FOR SURVEY AFTER CONSTRUCTION . 2016

5.3 Shaft Extension Surveys – Extension Types

5.3.1 Extension Up to 2.5 Years

The survey is to consist of:

• Checking and recording the bearing weardown measurements, as far as practicable.

• Visual Inspection of all accessible parts of the shafting system.

• Verification that the propeller is free of damages which may cause the propeller to be out of balance.

• Verification of the effectiveness of the inboard seal and outboard seals.

• Review of service records.

• Review of test records of:

- Lubricating Oil analysis (for oil lubricated shafts), or

- Fresh Water Sample test (for closed system fresh water lubricated shafts).

• Oil Sample Examination (for oil lubricated shafts), or Fresh Water Sample test (for closed system fresh water lubricated).

• Verification of no reported repairs by grinding or welding of shaft and/or propeller.

• Confirmation from the Chief Engineer that the shafting arrangement is in good working condition.

5.3.2 Extension Up to One (1) Year

The survey is to consist of:

• Visual Inspection of all accessible parts of the shafting system.

• Verification that the propeller is free of damages which may cause the propeller to be out of balance.

• Verification of the effectiveness of the inboard seal and outboard seals.

• Review of the previous weardown and/or clearance recordings.

• Review of service records.

• Review of test records of:

- Lubricating Oil analysis (for oil lubricated shafts), or

- Fresh Water Sample test (for closed system fresh water lubricated shafts).

• Oil Sample Examination (for oil lubricated shafts), or Fresh Water Sample test (for closed system fresh water lubricated).

• Verification of no reported repairs by grinding or welding of shaft and/or propeller.

• Confirmation from the Chief Engineer that the shafting arrangement is in good working condition.

5.3.3 Extension Up to Three (3) Months

The survey is to consist of:

• Visual Inspection of all accessible parts of the shafting system.

• Verification of the effectiveness of the inboard seal.

• Review of the previous weardown and/or clearance recordings.

• Review of service records.

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• Review of test records of:

- Lubricating Oil analysis (for oil lubricated shafts), or

- Fresh Water Sample test (for closed system fresh water lubricated shafts).

• Oil Sample Examination (for oil lubricated shafts), or Fresh Water Sample test (for closed system fresh water lubricated).

• Verification of no reported repairs by grinding or welding of shaft and/or propeller.

• Confirmation from the Chief Engineer that the shafting arrangement is in good working condition.

7 Water Lubricated Shafts (Open Systems) (2016) When the propeller is removed for any reason, the propeller hub is to be examined by a surface crack detection method after reinstallation.

7.1 Shaft Survey Methods

7.1.1 Method 4

The survey is to consist of:

• Drawing the shaft and examining the entire shaft (including liners, corrosion protection system and stress reducing features, where provided, inboard seal system and bearings.

• For keyed and keyless connections:

- Removing the propeller to expose the forward end of the taper,

- Performing a nondestructive examination (NDE) by a surface crack detection method all around the shaft in way of the forward portion of the taper section, including the keyway (if fitted). For shafts provided with liners, the NDE shall be extended to the after edge of the liner

• For flanged connection:

- Whenever the coupling bolts of any type of flange-connected shaft are removed or the flange radius is made accessible in connection with overhaul, repairs, or when deemed necessary by the Surveyor, the coupling bolts and flange radius are to be examined by means of a surface crack detection method.

• Checking and recording the bearing clearances.

• Verification that the propeller is free of damages which may cause the propeller to be out of balance.

• Verification of the satisfactory conditions of inboard seal during re-installation of the shaft and propeller.

7.3 Shaft Extension Surveys – Extension Types

7.3.1 Extension Up to One (1) Year

The survey is to consist of:

• Visual Inspection of all accessible parts of the shafting system.

• Verification that the propeller is free of damages which may cause the propeller to be out of balance.

• Checking and recording the clearances of bearing.

• Verification of the effectiveness of the inboard seal.

• Review of the previous clearance recordings.

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• Service records.

• Verification of no reported repairs by grinding or welding of shaft and/or propeller.

• Confirmation from the Chief Engineer that the shafting arrangement is in good working condition.

7.3.2 Extension Up to Three (3) Months

The survey is to consist of:

• Visual Inspection of all accessible parts of the shafting system.

• Verification that the propeller is free of damages which may cause the propeller to be out of balance.

• Verification of the effectiveness of the inboard seal.

• Review of the previous clearance recordings.

• Service records.

• Verification of no reported repairs by grinding or welding of shaft and/or propeller.

• Confirmation from the Chief Engineer that the shafting arrangement is in good working condition.

9 Vessels in Great Lakes Service (2005)

9.1 Tailshaft Survey

Where arrangements are such as to permit an effective nondestructive examination by a surface crack-detection method (such as magnetic particle or dye penetrant) all around the shaft in way of the forward portion of the taper section, including the end of keyway (if fitted), the shaft need not be drawn for examination in its entirety. Where arrangements of the flanged tailshaft permits effective examination of the flange fillet by a surface crack detection method, bearing weardown measurement and shaft seal effectiveness (oil-lubricated bearings), the shaft need not be withdrawn. The flange coupling bolts are to be examined by means of a surface crack detection method whenever they are removed. The Controllable-Pitch propeller hub is to be tested under operating conditions for oil tightness.

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