Section 33 Protective Coating Systems for Cargo Oil Tanks

3301. Application

The requirements of this Section apply to tests and inspection for the type approval of protective coat- ing systems in accordance with the requirements in Pt 3, Ch 1, 803. 2. of the Guidance.

3302. Data to be submitted

1. The following approval data are to be submitted to the Society in addition to those specified in

102.

(1) Copy of Technical Data Sheet, including : 3 copies

(a) product name and identification mark and/or number;

(b) materials, components and composition of the coating system, colours;

(c) minimum and maximum dry film thickness;

(d) application methods, tools and/or machines;

(e) condition of surface to be coated (de-rusting grade, cleanness, profile, etc.); and

(f) environmental limitations (temperature and humidity);

(g) dry-to recoat times and walk-on time

(2) Compatibility of shop primer with protective coating system : 3 copies(if any)

(3) Inspection and acceptance criteria of protective coating system : 3 copies

(4) Procedures for repair of protective coating system : 3 copies

2. The coating manufacturer should provide to the Society the following information;

(1) A detailed list of the production facilities.

(2) Names and location of raw material suppliers will be clearly stated.

(3) A detailed list of the test standards and equipment to be used, (Scope of approval).

(4) Details of quality control procedures employed.

(5) Details of any sub-contracting agreements.

(6) List of quality manuals, test procedures and instructions, records, etc.

(7)

Copy of any relevant certificates with their issue number and/or date e.g. Quality Management System certification.

(8) Material safety Data Sheet

3303. Data review and plant audit

1. The Society shall performed the data review and plant audit specified in Pt. 1, Annex 1-11, 2. and 3. of the Guidance Relating to the Rules for the Classification of Steel Ships to assure the manufacturing process (including that of subcontractor's works) and quality assurance of the pro- tective coating systems.

2. With the exception of early ‘scale up’ from lab to full production, adjustment outside the limi- tations listed in the QC instruction referred to below is not acceptable.

3. Unless justified by trials during the coating system’s development programme, or subsequent testing.

Any such adjustments must be agreed by the formulating technical centre. If formulation adjustment

is envisaged during the production process the maximum allowable limits will be approved by the formulating technical centre and clearly stated in the QC working procedures.

4. The manufacturer’s quality control system will ensure that all current production is the same for- mulation as that supplied for the Type Approval Certificate. Formulation change is not permissible without testing in accordance with the test procedures in this Section and the issue of a Type Approval Certificate by the Society.

5. Batch records including all QC test results such as viscosity, specific gravity and airless spray char- acteristics will be accurately recorded. Details of any additions will also be included.

6. Whenever possible, raw material supply and lot details for each coating batch will be traceable.

Exceptions may be where bulk supply such as solvents and pre-dissolved solid epoxies are stored

in tanks, in which case it may only be possible to record the supplier’s blend.

7. Dates, batch numbers and quantities supplied to each coating contract will be clearly recorded.

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8. All raw material supply must be accompanied the supplier’s ‘Certificate of Conformance’. The cer- tificate will include all requirements listed in the coating manufacturer’s QC system.

9. In the absence of a raw material supplier’s certificate of conformance, the coating manufacturer must verify conformance to all requirements listed in the coating manufacturer’s QC system.

10. Drums must be clearly marked with the details as described on the ‘Type Approval Certificate’.

11. Technical Data Sheets must comply with all the PSPC requirements. The QC system will ensure that all Product Technical Data Sheets are current.

12. QC procedures of the originating technical centre will verify that all production units comply with the above stipulations and that all raw material supply is approved by the technical centre.

3304. Performance standard

1. Protective coating systems are, in principal, to be an epoxy-based systems. All systems that are not an epoxy-based system applied according to this requirements are defined as an alternative system.

2. A multi-coat system with each coat of contrasting colour is recommended. The top coat shall be of a light colour(a colour that reflects light to an extent that a simple flash light (hand torch) will make inspection easy and fast. Normally light grey, buff, off-white, swimming pool blue/green, etc. easily distinguishable from rust.) in order to facilitate in-service inspection.

3. Protective coatings for Cargo Oil Tanks of Crude Oil Tankers shall satisfy the approval tests speci- fied in 3306. 2. and 3..

4. Epoxy-based systems which have documented field exposure for 5 years with a final coating con- dition of not less than "GOOD" may be accepted. In this case, field exposure for 5 years shall be satisfied following conditions.

(1) Coating manufacturer’s records should include the information indicated in followings and should be examined to confirm coating system has 5 years field exposure, and the current product is the same as that being assessed.

(a)

Original application records

(b) Original coating specification

(c)

Original technical data sheet,

(d) Current formulation’s unique identification (Code or number)

(e)

(f)

If the mixing ratio of base and curing agent has changed, a statement from the manu- facturer confirming that the composition of the mixed product is the same as the original

composition. This should be accompanied by an explanation of the modifications made.

Current technical data sheet for the current production site

(g) SG(Specific Gravity) and IR(Infra Red) identification of original product

(h) SG and IR identification of the current product

(i)

If original SG and IR cannot be provided then a statement from the manufacturer confirm- ing the readings for the current product are the same as those of the original.

(2) Either class survey records should be reviewed, or A joint (coating manufacturer/Society) survey of cargo tanks of a selected vessel should be carried out, to verify compliance with the require- ments of (1) and (5). The coating manufacturer’s representative is to be qualified to NACE Coating Inspector Level 2 or FROSIO Inspector Level III or equivalent as verified by the Administration.

(3) The selected vessel should have cargo tanks in regular use, of which:

(a) At least one tank is exposed to minimum temperature of 60 degree C plus or minus 3 degree

(b) For field exposure the ship should be trading in varied trade routes and carrying substantial varieties of crude oils including highest temperature and lowest pH limits to provide a real- istic sample: for example, three ships on three different trade areas with different varieties of crude cargoes.

(4) In the case that the selected vessel does not meet the requirements in (3) then the limitations

on lowest pH and Highest temperature of crude oils carried should be clearly stated on the type approval certificate.

(5) All cargo tanks should be in “GOOD” condition excluding mechanical damages, without touch up or repair in the prior 5 years. 2.6.1 “Good” is defined as: Condition with spot rusting on less than 3% of the area under consideration without visible failure of the coating. Rusting at

222 Guidance for Approval of Manufacturing Process and Type Approval, Etc. 2015

edges or welds, must be on less than 20% of edges or welds in the area under consideration. “Area under consideration” is the area defined as per PSPC-COT 4.4 and 4.5. In evaluating the figures given in the definition, an under deck area and an inner bottom area are to be treated separately.

5. In the case that a manufacturer wishes to have products which are manufactured in different locations under the same name, then infrared (IR) identification and specific gravity shall be used to demonstrate that they are the same coating, or individual approval tests will be required for the paint manufactured in each location.

3305. Test Laboratory

The test laboratory where testing is carried out in accordance with the requirements in 3304. 3. is to equip the test facilities so that they can perform the testing in accordance with the requirements in this Sec. and are to be accredited by any of followings;

(1) KoreaLaboratoryAccreditationScheme(KOLAS)

(2) International Laboratory Accreditation Cooperation(ILAC) or equivalent qualification

(3) ISO 9000 Quality Management System

3306. Type test

1. General

(1) Application of protective coating system

(a) There shall be a minimum of two stripe coats and two spray coats, except that the second stripe coat, by way of welded seams only, may be reduced in scope where it is proven that the NDFT can be met by the coats applied, in order to avoid unnecessary over-thickness.

(b) Stripe coats shall be applied by brush or roller.

(c) Each main coating layer shall be appropriately cured before application of the next coat, in accordance with coating manufacturer’s recommendations.

(d) Surface contaminants such as rust, grease, dust, salt, oil, etc., shall be removed prior to painting with proper method according to the paint manufacturer’s recommendation. Abrasive

inclusions embedded in the coating shall be removed. Job specifications shall include the

dry-to-recoat times and walk-on time given by the manufacturer.

(e) NDFT 320 μm with 90/10 rule(A 90/10 rule means that 90% of all thickness measurements

shall be greater than, or equal to, NDFT and none of the remaining 10% measurements

shall be below 0.9 x NDFT) for epoxy-based coatings; other systems to coating manu- facturer’s specifications.

(f) Maximum total dry film thickness according to manufacturer’s detailed specifications.

(g) Care shall be taken to avoid increasing the thickness in an exaggerated way. Wet film thickness shall be regularly checked during application.

(h) Thinner shall be limited to those types and quantities recommended by the manufacturer.

(2) Test gas composition

The test gas is based on the composition of the vapour phase in crude oil tanks and is to com- ply with the Table 3.33.1

Table 3.33.1 Test gas composition

(3) Test liquid

(a) start with distillate Marine Fuel, DMA Grade cosity of maximum 6 mm2/s at 40ºC (refer to

density at 15ºC: maximum 890 kg/m3, vis- KS M ISO 8217) ;

(b) add naphthenic acid up to an acid number of 2.5±0.1 mg KOH/g (refer to KS M 6618) ;

ISO

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(c) add benzene/ toluene (1:1 ratio) up to a total of 8.0±0.2% w/w of the DMA;

(d) add artificial ture ;

seawater (refer to ASTM D1141) up to a total of 5.0±0.2% w/w to the mix-

(e) add H2S dissolved in a liquid carrier (in order to get 5±1 ppm w/w H2S in the total test liquid);

(f) thoroughly mix the above constituents immediately prior to use; and

(g) once the mixture is completed, it should be tested to confirm the mixture is compliant with the test mixture concentrations.

(h) To prevent the risk of H2S release into the test facility, it is recommended to use a stock solution for steps (a) to (d), then fill the test containers and complete the test solution with steps (e) and (f).

2. Gastight cabinet test

(1) Test condition

The vapour test shall be carried out in a gastight cabinet. The dimensions and design of the air tight gas cabinet are not critical, provided the requirements of subparagraphs (f) to (j) below are met.

(a) The exposure time is 90 days.

(b) Testing shall be carried out using duplicate panels;a third panel shall be prepared and stored

at ambient conditions to act as a reference panel during final evaluation of the test panels.

(c) The size of each test panel is 150 mm x 100 mm x 3 mm.

(d) The panels shall be treated according to 1. (1) above.

(e) The zinc silicate shop primer, when used, shall be weathered for at least 2 months and

cleaned by low pressure fresh water washing. The exact method of shop primer preparation before being over coated shall be reported, and the judgement issued for that specific system. The reverse side and edges of the test piece shall be coated appropriately, in order not to influence the test results.

(f) Inside the gastight cabinet a trough shall be present. This trough shall be filled with 2 ±

0.2 l of water. The water in the trough shall be drained and renewed prior to each time the test gas is refreshed.

(g) The vapour spaces inside the gastight cabinet shall be filled with a mixture of test gas as per 1. (2) above. The cabinet atmosphere shall be maintained over the period of the test.

When the gas is outside the scope of the test method, it shall be refreshed. The monitoring frequency and method, and the date and time for refreshing the test gas, shall be in the test

report.

(h) The atmosphere in the test cabinet shall at all times be 95 ± 5% relative humidity.

(i) Temperature of the test atmosphere shall be 60 ± 3 °C.

(j) A stand for the test panels shall be made of a suitable inert material to hold the panels ver- tically spaced at least 20 mm between panels. The stand shall be positioned in the cabinet

to ensure the lower edge of the panels is at least 200 mm above the height of the water and at least 100 mm from the walls of the cabinet. If two shelves are in the cabinet, care shall be taken to ensure solution does not drip on to the lower panels.

(2) Test results

(A) Prior to testing, the following measured data of each coating composing the coating system, in- cluding the zinc silicate shop primer when used under the coating system, shall be reported:

(a)

infrared (IR) identification of the base and hardener components of the coating;

(b) specific gravity (refer to KS M ISO 2811-1/4) of the base and hardener components of the paint; and

(c)

mean dry film thickness (DFT) (by using a template). (Six equally distributed measuring points are used on panels size 150mm x 100mm.)

(B) After completion of the test duration, the panels shall be removed from the cabinet and rinsed with warm tap water. The panels shall be dried by blotting with absorbent paper and, then, eval- uated for rust and blistering within 24 hours of the end of the test.

(C) After testing, the following measured data shall be reported:

(a) blisters and rust. (refer to KS M ISO 4628-2 and KS M ISO 4628-3)

(3) Acceptance criteria

(A) The test results based on (2) above shall satisfy the following criteria, the poorest performing of the duplicate test panels shall be used in the report:

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(B) When evaluating test panels, blistering or rusting within 5 mm of the panel edge shall be ignored.

(4) Test report

The test report shall include the following information:

(A) coating manufacturers' name and manufacturing site;

(B) dates of test;

(C) product name/identification of each coat and, where applicable, zinc silicate shop primer;

(D) batch numbers of each component of each product;

(E) details of surface preparation of steel panels, before shop primer application, and treatment

of the shop primer before over coating where relevant and at a minimum including the fol- lowing:

(a) surface treatment, or treatment of weathered shop primer, and any other important in- formation on treatment influencing the performance; and

(b) water soluble salt level measured on the steel prior to application of the shop primer(re- fer to KS M ISO 8502)

(F) details of coating system, including the following:

(a) zinc silicate shop primer if relevant, its secondary surface pretreatment and condition un- der which applied, weathering period;

(b) number of coats, including the shop primer and thickness of each;

(c)

mean dry film thickness (DFT) prior to testing

(d) thinner if used;

(e)

(f)

humidity;

air temperature;

(g) steel temperature;

(G) details of schedule for refreshing the test gas;

(H) test results according to 2. (2); and

(I) results according to 2. (3).

3. Immersion test

(1) Test condition

(a)

The exposure time is 180 days.

(b) The test liquid should be made as per 1. (3) above.

(c)

The test liquid should be added to a container with an inside flat bottom until a column of the test liquid of height of 400 mm is reached, resulting in an aqueous phase of 20 mm. Any other alternative test setup, using an identical test liquid, which will also result in the immersion of the test panel in 20 mm of the aqueous phase, is also accepted. This can be achieved by using, for instance, inert marbles.

(d) The temperature of the test liquid should be 60 ± 2℃ and should be uniform and main-

tained constant with recognized methods such as water or oil bath or air circulation oven

capable of keeping the immersion liquid within the required temperature range.

(e) Test panels shall be positioned vertically and fully immersed during the test.

(f) Testing shall be carried out using duplicate panels.

(g) Inert spacers which do not cover the test area shall be used to separate test panels.

(h) The size of each test panel is 150 mm x 100 mm x 3 mm.

(i) The panels shall be treated according to 1. (1) above.

(j) The zinc silicate shop primer, when used, shall be weathered for at least 2 months and cleaned by low pressure fresh water washing. The exact method of shop primer preparation before being over coated shall be reported, and the judgment issued for that specific system. The reverse side, and edges, of the test piece shall be coated appropriately, in order not to influence the test results.

(k) After the full immersion test period is completed the panels shall be removed from the test liquid and wiped with dry clean cloth before evaluation of the panels.

(l) Evaluation of the test panels shall be done within 24 hours after completion of the test.

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(2) Test results

(A) Prior to testing, the following measured data of each coating composing the coating system, including the zinc silicate shop primer when used under the coating system, shall be re- ported:

(a) infrared (IR) identification of the base and hardener components of the coating;

(b) specific gravity of the base and hardener components of the paint (refer to KS M ISO

2811-1/4) ;

(c) mean dry film thickness (DFT) (by using a template). (Six equally distributed measuring points are used on panels size 150mm x 100mm.)

(B) After testing, the following measured data shall be reported:

(a) blisters and rust (refer to KS M ISO 4628-2 and KS M ISO 4628-3)

(3) Acceptance criteria

(A) The test results based on (2) above shall satisfy the following criteria, the poorest perform- ing of the duplicate test panels shall be used in the report.:

(B) When evaluating test panels, blistering or rusting within 5 mm of the panel edge should be ignored.

(4) Test report

The test report shall include the following information:

(A) coating manufacturers' name and manufacturing site;

(B) dates of test;

(C) product name/identification of each coat and, where applicable, zinc silicate shop primer;

(D) batch numbers of each component of each product;

(E) details of surface preparation of steel panels, before shop primer application, and treatment of the shop primer before over coating where relevant and at a minimum including the fol- lowing:

(a) surface treatment, or treatment of weathered shop primer, and any other important in- formation on treatment influencing the performance; and

(b) water soluble salt level measured on the steel prior to application of the shop primer(re- fer to KS M ISO 8502)

(F) details of coating system, including the following:

(a) zinc silicate shop primer if relevant, its secondary surface pretreatment and condition un- der which applied, weathering period;

(b) number of coats, including the shop primer and thickness of each;

(c)

mean dry film thickness (DFT) prior to testing thinner if used;

(d) humidity;

(e)

(f)

(g)

air temperature; steel temperature;

(G) test results according to 3. (2) above; and

(H) results according to 3. (3) above.

3307. Type Approval Certificates

1. If the type tests specified in 3304. 3. or 5 years field exposure test specified in 3304. 4. are sat- isfactory, a Type Approval Certificate will be issued to include both the epoxy and the shop primer.

2. In case where 5 years field exposure test specified in 3304. 4. are performed, The Type Approval Certificate shall reference the joint survey report specified in 3304. 4. (2)

3. In case where 5 years field exposure test specified in 3304. 4. are performed, If the applied NDFT is greater than required in 3306. 1. (1), (e) the applied NDFT will be the minimum to be applied during construction. This will be reported prominently on the Type Approval Certificate.

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4. In case where the epoxy has been tested without shop primer on bare prepared steel with sat- isfactory, a Type Approval Certificate will be issued. The Type Approval Certificate will just re- cord the epoxy.

5. The Type Approval Certificate is invalid if the formulation of either the epoxy or the shop primer is changed. It is the responsibility of the manufacturer to inform class immediately of any changes to the formulation.

3308. Compatability of shop primer

1. If a zinc silicate shop primer has passed the type test as part of an epoxy coating system, it may be used in combination with other approved epoxy coatings provided that the compatibility has been confirmed by the immersion test of 3306. 3. or test in accordance with Ch 3, Sec 30 in this Guidance.

2. In case where same epoxy coating system is to applied on the different shop primers, each combi- nation to be type tested in accordance with 3304.. However, if each shop primer have already passed the type test as part of an epoxy coating system, the compatibility of shop primer can be confirmed by the test in accordance with 1. above.

3. If the test or tests specified above 1. are satisfactory, a Type Approval Certificate will be issued.

In this instance the Type Approval Certificate will include the details of the epoxy and shop primers with which it has been tested that have passed these requirements.

a list of all

3309. Dealing after approval

1. The protective coating systems satisfied for the tests specified in 3304. 3. are to be use of the epoxy with all the named shop primers or on bare prepared steel.

allowed the

2. The protective coating systems satisfied for the tests without shop primer according to 3307. 4. are to be allowed the use of the epoxy on bare prepared steel only.

3. In all cases of approval by 5 years field exposure test specified in 3304. 4., the shop primer shall be removed prior to application of the approved epoxy based system coating, unless it can be con- firmed that the shop primer applied during construction, is identical in formulation to that applied in the selected vessel used as a basis of the approval.

3310. Alternative systems

1. All systems that are not applied according to IMO PSPC(IMO Resolution 288(87)) 4.6 are de- fined as an alternative system.

2. Acceptance of alternative systems will be subject to documented evidence that they ensure a corro- sion prevention performance at least equivalent to that indicated in IMO PSPC.

3. The documented evidence shall consist of satisfactory performance corresponding to a target useful in either actual field exposure of continuous trading with crude oil cargoes for 5 years with final coating condition not less than "GOOD" or testing according to this Section.

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