Annex 10 - Recommended Procedures for Thickness Measurement
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Resolutions - Assembly - IMO Resolution A.744(18) Guidelines on the Enhanced Programme of Inspections During Surveys for Bulk Carriers and Oil Tankers (Adopted on 4 November 1993) - Annex B - Guidelines on the Enhanced Programme of Inspection During Surveys for Oil Tankers - Part B - Guidelines on the Enhanced Programme of Inspections During Surveys of Oil Tankers other than Double Hull Oil Tankers - Annex 10 - Recommended Procedures for Thickness Measurement

Annex 10 - Recommended Procedures for Thickness Measurement

  1 General

These procedures should be used for recording thickness measurements as required by annexes 2 and 4.

  2 Reporting forms TM1, TM2-T, TM3-T, TM4-T, TM5-T and TM6-T, set out in appendix 2, should be used for recording thickness measurements and the maximum allowable diminution should be stated.

  3 appendix 3 contains guidance diagrams and notes relating to the reporting forms and the requirements for thickness measurement.

  4 The reporting forms should, where appropriate, be supplemented by data presented on structural sketches.

Appendix 1 - General Particulars

APPENDIX 1
GENERAL PARTICULARS
Ship's name:
IMO number:
Class administration identity number:
Port of registry:
Gross tonnage:
Deadweight:
Date of build:
Classification society:
Name of company performing thickness measurement
Thickness measurement company certified by:
Certificate number:
Certificate valid from:..........................................to...................................................................
Place of measurement:
First date of measurement:
Last date of measurement:
renewal survey/intermediate survey due *:
Details of measurement equipment:  
Qualification of operator:  
Report number: consisting of pages
Name of Operator:........................................... Name of surveyor:...........................................
Signature of operator:...................................... Signature of surveyor .....................................
Company official stamp:................................... Administration:.............................................. Official stamp:
* Delete as appropriate  

Appendix 2 - Reports on Thickness Measurement

(TM1-T)

Report on Thickness Measurement of all Deck Plating, all Bottom Shell Plating or Side Shell Plating

Report on thickness measurement or all deck plating, all bottom shell plating or side shell plating (TM1T)
Ship's name..........................IMO Number..........................Class identity NO..........................Report No....................
Strake Position  
Plate Position No of Letter Org Thk mm Forward Reading Aft Reading Mean Diminution
Gauged Diminution P Diminution S Gauged Diminution P Diminution S
P S mm % mm % P S mm % mm % P S
12th forward                                
11th                                
10th                                
9th                                
8th                                
7th                                
6th                                
5th                                
4th                                
3rd                                
2nd                                
1st                                
Amidships                                
1st aft                                
2nd                                
3rd                                
4th                                
5th                                
6th                                
7th                                
8th                                
9th                                
10th                                
11th                                
12th                                
Operators signature................ Surveyors Signature............................           Notes. See Reverse

Notes to (TM1-T)

  1 This report should be used for recording the thickness measurement of:

  • 1.1 All strength deck plating within the cargo area.

  • 1.2 All keel, bottom shell plating and bilge plating within the cargo area.

  • 1.3 Side shell plating including selected wind and water strakes outisde the cargo area.

  2 The strake position should be clearly indicated as follows:

  • 2.1 For strength deck indicate the number of the strake of plating inboard from the stringer plate.

  • 2.2 For bottom plating indicate the number of the strake of plating outboard from the keel plate.

  • 2.3 For side shell plating give the number of the strake of plating below sheerstrake and letter as shown on shell expansion.

  3 For oil tankers all deck plating strakes should be recorded, for ore/oil ships only the deck plating strakes outside line of openings should be recorded.

  4 Measurements should be taken at the forward and aft areas of all plates and where plates cross ballast/cargo tank boundaries separate measurements for the area of plating in way of each type of tank should be recorded.

  5 The single measurements recorded should represent the average of multiple measurements.

(TM2-T(1))

Report on Thickness Measurement of Shell and Deck Plating (one, two or three transverse sections)

Report on thickness measurement or all deck plating, all bottom shell plating or side shell plating (one, two or three transverse sections) (TM2T(1))
Ship's name .......................... IMO Number .......................... Class identity NO. ......................... Report No ....................
STRENGTH DECK AND SHEERSTRAKE PLATING
  First Transverse Section at Frame Number   Second Transverse Section at Frame Number Third Transverse Section at Frame Number
Strake Position No of Letter Org Thk mm Gauged Diminution P Diminution S No of Letter Org Thk mm Gauged Diminution P Diminution S No of Letter Org Thk mm Gauged Diminution P Diminution S
P S mm % mm % mm % mm % mm % P S mm % mm %
Stringer Plate                                                
1st stroke inboard                                                
2nd                                                
3rd                                                
4th                                                
5th                                                
6th                                                
7th                                                
8th                                                
9th                                                
10th                                                
11th                                                
12th                                                
13th                                                
14th                                                
centre stroke                                                
ahear stroke                                                
Topside total                                                
                                                 
Operators signature ................ Surveyors Signature ............................               Notes. See Reverse  

Notes to (TM2-T(1))

  1 This report should be used for recording the thickness measurement of strength deck plating and sheerstrake plating transverse sections:

One, two or three sections within the cargo area comprising of the structural items (1), (2) and (3) as shown on the diagrams of typical transverse section indicating longitudinal and transverse members, in appendix 3.

  2 For oil tankers all deck plating strakes should be recorded, for ore/oil ships only the deck plating strakes outside line of openings should be recorded.

  3 The topside area comprises deck plating, stringer plate and sheerstrake (including rounded gunwales).

  4 The exact frame station of measurement should be stated.

  5 The single measurements recorded should represent the average of multiple measurements.

(TM2-T(2))

Report on Thickness Measurement of Shell and Deck Plating (one, two or three transverse sections)

Report on thickness measurement or all deck plating, all bottom shell plating or side shell plating (one, two or three transverse sections) (TM2T(2))
Ship's name .......................... IMO Number .......................... Class identity NO. ......................... Report No. ...................
SHELL PLATING
  First Transverse Section at Frame Number   Second Transverse Section at Frame Number Third Transverse Section at Frame Number
Strake Position No of Letter Org Thk mm Gauged Diminution P Diminution S No. of Letter Org Thk mm Gauged Diminution P Diminution S No of Letter Org Thk mm Gauged Diminution P Diminution S
P S mm % mm % P S mm % mm % P S mm % mm %
1st below sheet stroke                                                
2nd                                                
3rd                                                
4th                                                
5th                                                
6th                                                
7th                                                
8th                                                
9th                                                
10th                                                
11th                                                
12th                                                
13th                                                
14th                                                
15th                                                
16th                                                
17th                                                
18th                                                
19th                                                
20th                                                
keel stroke                                                
Bottom Total                                                
Operators signature ................ Surveyors Signature ............................               Notes. See Reverse

  1 This report should be used for recording the thickness measurements of shell plating transverse sections:

One, two or three sections within the cargo area comprising of the structural items (4), (5), (6), and (7) as shown on the diagrams of typical transverse section indicating longitudinal and transverse members, in appendix 3.

  2 The bottom area comprises keel, bottom and bilge plating.

  3 The exact frame station of measurement should be stated.

  4 The single measurements recorded should represent the average of multiple measurements.

(TM3-T)

Report on Thickness Measurement of longitudinal members (one, two or three transverse sections)

Report on thickness measurement of longitudinal members (one, two or three transverse sections) (TM3T))
Ship's name .......................... IMO Number .......................... Class identity NO. ......................... Report No. ...................
  First Transverse Section at Frame Number   Second Transverse Section at Frame Number Third Transverse Section at Frame Number
STRUCTURAL MEMBER No of Letter Org Thk mm Gauged Diminution P Diminution S No. of Letter Org Thk mm Gauged Diminution P Diminution S No of Letter Org Thk mm Gauged Diminution P Diminution S
P S mm % mm % mm % mm % mm % P S mm % mm %
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
Operators signature................ Surveyors Signature............................               Notes. See Reverse  

Notes to (TM3-T)

  1 This report should be used for recording the thickness measurement of longitudinal members at transverse sections:

One, two or three within the cargo area comprising of the structural items (8) to (20) as shown on the diagrams of typical transverse section indicating longitudinal and transverse members, in appendix 3.

  2 The exact frame station of measurement should be stated.

  3 The single measurements recorded should represent the average of multiple measurements.

(TM4-T)

Report on Thickness Measurement of Transverse Structural Members in the Cargo and Ballast Tanks Within the Cargo Area

Report on thickness measurement of transverse structural members in the cargo and ballast tanks within the cargo area (TM4 T)
Ships's name ................IMO number .................. Class identity.................... Report No. .............
TANK DESCRIPTION :
LOCATION OF STRUCTURE :
STRUCTURAL MEMBER ITEM Original Thickness mm Gauged Diminution P Diminution S
Port Starboard mm % mm %
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
Operators Signature ........................... Surveyors Signature ....................... Note See Reverse

Notes to (TM4-T)

  1 This report should be used for recording the thickness measurement of transverse structural members, comprising of the appropriate structural items (25) to (32) as shown on the diagrams of typical transverse section indicating longitudinal and transverse members, in appendix 3.

  2 Guidance for areas of measurement is indicated in Tables 1 to 3 of appendix 3.

  3 The single measurements recorded should represent the average of multiple measurements.

(TM5-T)

Report on Thickness Measurement of W.T./O.T. Transverse Bulkheads Within the Cargo Tank or Cargo Hold Spaces

Report on thickness measurement W.T./O.T. of transverse structural members in the cargo and ballast tanks within the cargo area (TM5 - T)
Ships's name ................ IMO number .................. Class identity .................... Report No. .............
TANK DESCRIPTION :
LOCATION OF STRUCTURE :
STRUCTURAL COMPONENT (PLATING /STIFFENER) ITEM Original Thickness mm Gauged Diminution P Diminution S
Port Starboard mm % mm %
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
Operators Signature ........................... Surveyors Signature ....................... Note See Reverse

Notes to (TM5-T)

  1 This report should be used for recording the thickness measurement of W.T./O.T. transverse bulkheads.

  2 Guidance for areas of measurement is indicated in Tables 1 to 3 of appendix 3.

  3 The single measurements recorded should represent the average of multiple measurements.

(TM6-T)

Report on Thickness Measurement of Miscellaneous Structural Members

Report on thickness measurement of miscellaneous structural members (TM6 T)
Ships's name ................IMO number .................. Class identity.................... Report No..............
STRUCTURAL MEMBER :
LOCATION OF STRUCTURE :
Description Org Gauged Diminution P Diminution S
Port Starboard mm % mm %
               
               
               
               
               
               
               
               
               
               
Operators Signature ........................... Surveyors Signature ....................... Note See Reverse

Notes to (TM6-T)

  1 This report should be used for recording the thickness measurement of miscellaneous structural members including the structural items (36), (37) and (38) shown in appendix 3.

  2 The single measurements recorded should represent the average of multiple measurements.

Appendix 3 - Guidance of Thickness Measurement

Figure A Typical Transverse Section of Oil Tanker Indicating Longitudinal and Transverse Members

Figure B Typical Transverse Section of Ore/Oil Ship Indicating Longitudinal and Transverse Members

Transverse Section Outline

Figure C Typical Transverse Sections

Figure D Close-up Survey Requirements


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