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資料5-8
SUB-COMMITTEE ON SHIP DESIGN AND EQUIPMENT
48th session
Agenda item 12
DE 48/12/2
27 December 2004
Original: ENGLISH
PERFORMANCE STANDARDS FOR PROTECTIVE COATINGS
Comments on alternative procedures in the draft performance standards for protective coatings
Submitted by Japan
SUMMARY
Executive summary: This document provides comments and proposal of modification to the draft alternative procedures in the draft performance standard of coating system in document DE 48/12.
Action to be taken: Paragraph 4
Related documents: DE 48/12 |
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Background
1 This document provides the proposal of modification to the draft alternative procedures in the draft performance standard of coating as contained in document DE 48/12. This document has been submitted in accordance with the provisions of paragraph 4.10.5 of the Guidelines on the organization and method of work of the MSC and MEPC and their subsidiary bodies (MSC/Circ.1099/MEPC/Circ.405).
Comments and proposal to the draft alternative procedures
2 Japan supports the idea of "Alternative procedures" in the draft performance standard of coating as contained in document DE 48/12. In addition, Japan believes that, in order to effectively apply the alternative procedures, it is important to provide a guidance on test procedures for coating qualification and surface preparation.
3 Japan provides, in the annex to this document, a proposed draft test procedure for coating qualification and surface preparation, for the consideration of the Sub-Committee.
Action requested of the Sub-Committee
4 The Sub-Committee is invited to consider the above comments and the proposal as set out in the annex to this document, and take action as appropriate.
For reasons of economy, this document is printed in a limited number. Delegates are kindly asked to bring their copies to meetings and not to request additional copies. |
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ANNEX
PROPOSAL OF MODIFICATION TO THE DRAFT PERFORMANCE STANDARD FOR PROTECTIVE COATING
1 Renumber the draft paragraph 4 "Alternative procedures", as follows:
"5 4 ALTERNATIVE PROCEDURES"
Renumber 4.1 as 5.1.
Renumber 4.2 as 5.2.
2 Renumber 4.3 as 5.3, and modify it in order to introduce the proposed test procedure for coating qualification and surface preparation, as follows:
5.3  As a minimum, the documented evidence shall consist of satisfactory performance corresponding to that of the coating system which conforms to the coating standard described in section 3, a target useful life of 15 years , in either actual field exposure (ballast spaces) or laboratory testing. Laboratory tests shall be conducted in accordance with the test procedure given in Annex of this document.
3 Add the following annex at the end of the draft proposed standards:
"Annex
Draft Guidelines on test procedures for coating qualification and surface preparation for ballast tank coating
1 Scope
These Guidelines provide details of the method of laboratory test required by performance standards for protective coatings.
2 Definitions
Coating specification means the specification of coating system which includes the type of coating system and steel preparation.
3 Testing
Coating specification shall be verified by the following tests. The test procedures shall comply with Appendix 1 or Appendix 2 to this annex:
.1 Test by simulated ballast tank conditions; and
.2 Condensation chamber tests.
Appendix 1 - Test on simulated ballast tank conditions
1 Test condition
Test on simulated ballast tank conditions shall satisfy each of the following conditions:
.1 The test shall be carried out for 180 days.
.2 The number of test panels is at least 4 pieces.
.3 The size of test panel is 200mm* 400mm* 5mm.
.4 The reverse side of the test piece shall be painted appropriately, in order not to effect on test results.
.5 As simulating the condition of actual ballast tank, the test cycle run for two weeks with seawater or artificial seawater and one week empty. The temperature of the seawater keep about 35℃.
.6 One piece of test panel is heated for 12 hours of 50℃ and cooled for 12 hours of 20℃ in order to simulate upper deck condition.
.7 One piece of test panel has a fixed sacrificial zinc anode in order to evaluate the effect of cathodic protection.
.8 One piece of test panel is cooled on the reverse side, in order to give a temperature gradient in order to simulate a cooled bulkhead in a ballast wing tank, and splashed on seawater or artificial seawater in order to simulate a ship's pitching and rolling motion. The gradient of temperature is approximately 20℃, and the interval of splashing is 3 seconds or faster.
.9 One piece of test panel is cyclically splashed or artificial seawater on seawater in order to simulate a ship's pitching and rolling motion. The interval of splashing is 3 seconds or faster.
2 Test results
2.1 Prior the testing, following measured data of the coating system shall be reported:
.1 IR identification (main components);
.2 Specific gravity according to ISO 2811-74;
.3 Number of pinholes; and
.4 Flexibility* according to ASTM D4145.
*Flexibility shall be measured for the maximum DFT. This can be verified using another test panel.
2.2 After the testing, following measured data shall be reported:
.1 Blisters and rust according to ISO 4628/2 and ISO 4628/3;
.2 Dry film thickness (DFT);
.3 Number of pinholes;
.4 Adhesion value according to ISO 4624;
.5 Flexibility according to ASTM D4145; and
.6 Cathodic protection weight loss/current demand.
3 Classification criteria
The test results based on paragraph 2 shall satisfy the following criteria.
| Item |
Criteria |
Blisters on Panel
Rust on Panel |
No blisters
Ri 0 (0%) |
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4 Test report
The test report shall include the following information:
.1 Name of the manufacture;
.2 Date of tests;
.3 Product name/identification, include both of paint and primer;
.4 Batch number;
.5 Data of surface preparation on steel panels include following data:
- surface treatment;
- water soluble salts limit;
- dust; and
- abrasive inclusion;
.6 Application data of coating system include following data:
- shop primed or not;
- number of coats;
- recoat interval *;
- dry film thickness (DFT) prior testing *;
- maximum DFT according to 2.1.4 *;
- thinner *;
- humidity *;
- air temperature *; and
- steel temperature;
* Both of actual specimen data and manufacturer's requirement/recommendation.
.7 Test result according to paragraph 2; and
.8 Judgment according to paragraph 3.
Appendix 2 - Condensation chamber test
1 Test condition
Condensation chamber test shall be conducted in accordance with ISO 6270.
2 Test results
According to appendix 1, paragraph 2, except of appendix 1, paragraph 2.1.4 and 2.2.6.
3 Classification criteria
The test results based on paragraph 2 shall satisfy the following criteria.
| Item |
Criteria |
Blisters on Panel
Rust on Panel |
No blisters
Ri0 (0%) |
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4 Test report
According to Appendix 1, paragraph 4.
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