Annex 8 - Recommended Procedures for Thickness Measurements
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 A - Guidelines on the Enhanced Programme of Inspections During Surveys for Bulk Carriers - Part A - Guidelines on the Enhanced Programme of Inspections During Survey of Bulk Carriers Having Single-side Skin Construction - Annex 8 - Recommended Procedures for Thickness Measurements

Annex 8 - Recommended Procedures for Thickness Measurements

General

  1 These procedures should be used for recording thickness measurements as required by annex 2.

  2 Reporting forms TM1-BC, TM2-BC, TM3-BC, TM4-BC, TM5-BC, TM6-BC and TM7-BC, 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

General Particulars

Ships 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:
   

Appendix 2 - Reports on Thickness Measurement

(TM1-BC)

Table TM1-BC Report on thickness measurement or all deck plating, all bottom shell platingor side shell plating

Ship's name..........................IMO Number..........................Class identity NO..........................Report No....................
Strake Position  
Plate Position No
or
Letter
Org
Thk.
mm
Forward Reading Aft Reading Diminution S
Gauged Diminution P Gauged Diminution P Diminution S Mean Diminution
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-BC)

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

  • .1 All strength deck plating within the cargo length area.

  • .2 Keel, bottom shell plating and bilge plating within the cargo length area.

  • .3 Side shell plating that is all wind and water strakes within the cargo length area.

  • .4 Side shell plating that is selected wind and water strakes outside the cargo length 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 strake plating outboard from the keel plate.

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

  3 On the deck plating strake outside line of openings should be recorded.

  4 Measurements should be taken at the forward and aft areas of all plates and the single measurements recorded should represent the average of multiple measurements.

(TM2-BC(1))

Table TM2-BC(1) Report on Thickness Measurement of Shell and Deck Plating (one, two or three transverse sections)

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 % mm Gauged Diminution P Diminution S P S Gauged Diminution P Diminution S
P S mm % No of Letter Org Thk mm mm % mm % No of Letter Org Thk 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-BC(1))

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

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

  2 Only the deck plating outside the 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-BC(2))

Table TM2-BC(2) Report on thickness measurement or all deck plating, all bottom shell platingor side shell plating (one, two or three transverse sections)

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 % mm Gauged Diminution P Diminution S P S Gauged Diminution P Diminution S
P S mm % No of Letter Org Thk mm mm % mm % No of Letter Org Thk 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

Notes to (TM2-BC(2))

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

Two or three sections within the cargo length area, comprising of the structural items (8) to (2) as shown on the diagram of typical transverse section indicating longitudinal and transverse members, in appendix 3.

  2 The exact frame station of measurements should be stated.

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

(TM3-BC)

Table TM3-BC Report on thickness measurement of longitudinal members (one, two or threetransverse sections)

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 Item
No.
Org
Thk.
mm
Gauged Diminution P Diminution S % mm Gauged Diminution P Diminution S P S Gauged Diminution P Diminution S
P S mm % No of Letter Org
Thk.
mm
mm % mm % No of Letter Org Thk mm P S mm % mm %
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
                                                 
Operators signature................ Surveyors Signature............................               Notes. See Reverse

Notes to (TM3-BC)

  1 This report should be used for recording the thickness measurement of transverse structural members, comprising of the appropriate structural items (23) to (25) as shown on the diagram 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 to appendix 3.

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

(TM4-BC)

Table TM4-BC Report on thickness measurement of transverse structural members in the cargoand ballast tanks within the cargo tank length

Ship's name.......................... IMO Number.......................... Class identity NO.......................... Report No....................
TANK DESCRIPTION :
LOCATION OF STRUCTURE:
STRUCTURAL MEMBER ITEM Original Thickness mm Gauged Diminution P Diminution S
P S mm % mm %
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
Operators signature ...................... Surveyors signature .................................... Notes - see following page

Notes to (TM4-BC)

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

Two or three sections within the cargo length area comprising of the structural items (4), (5), (6) and (7) as shown on the diagram 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.

(TM5-BC)

Table TM5-BC Report on thickness measurement of cargo hold transverse bulkheads

Ship's name.......................... IMO Number.......................... Class identity No......................... Report No..................
TANK/HOLD DESCRIPTION
LOCATION OF STRUCTURE: FRAME No :
STRUCTURAL COMPONENT (PLATING/STIFFENER) Original Thickness mm Gauged Diminution
P
Diminution
S
PORT STARBOARD mm % mm %
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
Operators signature ...................... Surveyors signature ........................... Notes - see following page

Notes to (TM5-BC)

  1 This report form should be used for recording the thickness measurement of cargo hold 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-BC)

Table TM6-BC Report on thickness measurement of Miscellaneous Structural members

Ship's name.......................... IMO Number.......................... Class identity No......................... Report No..................
TANK/HOLD DESCRIPTION : SKETCH
LOCATION OF STRUCTURE :  
Description Orig.
Thk.
mm
P S mm mm %    
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
Operators signature ...................... Surveyors signature ................... Notes - see following page

Notes to (TM6-BC)

  1 The report should be used for recording thickness measurement of miscellaneous structural members including the structural items (28), (29), (30) and (31) as shown on the diagram 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.

(TM7-BC)

Table TM7-BC Report on thickness measurement of cargo hold transverse frames

Ship's name.......................... IMO Number.......................... Class identity NO.......................... Report No....................
CARGO HOLD No.
       
Orig.
Thk.
mm
Gauged Diminution
P
Diminution
S
% Gauged Diminution
P
Diminution
S
P Gauged Diminution
P
Diminution
S
P S mm mm % Orig.
Thk.
mm
S mm % mm % Orig.
Thk.
mm
P S mm % mm %
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
                                           
Operators signature ................ Surveyors Signature ............................     Notes - see following page

Notes to (TM7-BC)

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

  • cargo hold transverse frames; and
  • structural item number 34 as shown on the diagram 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 (see also diagram).

Figure 1

Appendix 3 - Guidance of Thickness Measurement

Figure A Guidance on Thickness Measurement

Figure B Transverse Section Outline

Table 1 Close-up Survey and Thickness Measurement Areas

Appendix 4 - Thickness measurement and typical transverse section indicating longitudinal and transverse members

Figure A

Appendix 5 - Thickness measurements and close-up surrey requirements

Figure A


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