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Hyun- Kug Lee (hyunkug.lee@samsung.com)

Effects of IMO PSPC. Hyun- Kug Lee (hyunkug.lee@samsung.com). Tripartite Meeting 20 th ~21 st September, 2007. 1. What’s problem with PSPC ?. 2. Effect of PSPC. Contents. What’s problem?. Impractical Rule for Shipbuilder. Remarkable quality improvement is not expected.

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Hyun- Kug Lee (hyunkug.lee@samsung.com)

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  1. Effects of IMO PSPC Hyun- Kug Lee (hyunkug.lee@samsung.com) Tripartite Meeting 20th~21st September, 2007

  2. 1 What’s problem with PSPC ? 2 Effect of PSPC Contents

  3. What’s problem? • Impractical Rule for Shipbuilder. • Remarkable quality improvement is not expected. • Authority and Responsibility is not clear.

  4. Why impractical rule ! • Each shipyard has different practice because of difference of facility and process for the coating. • However, PSPC require unified practice. • Shipbuilder’s experience and practice havenot been reflected in the PSPC. • Even though, PSPC effect to the Shipyard facility, process and practice. • Inspection for Inspection is required. • Excessive inspections will not provide enhanced quality.

  5. Electrostatic Spray Air Spray Roller Brush Airless Spray Soft Brush Soft Roller Brush-Roller? Twin-feed Spray Everything are evolving ! IACS/Industry Guideline allow to use brush or roller. However, shipowner’s intention was the brush during JWG meeting.

  6. x 4 Microscope x 12.5 Microscope Application Magnified Photo SP R A Y B R U S H R O L L E R • Porosities can be found when 12.5 times magnified by microscope. • The porosities will be covered by spraying ofmain coat. Everything are evolving !

  7. About 2mm R 3 pass Grinding Practice also ! • Edge Grinding Automatic Cold Rolling Disk Grinding Bite Milling To reduce stripe coat However, PSPC requires that 2 stripe coats to be applied to the edges regardless of shape of edges.

  8. Practice also ! • Edge Grinding Shipyard experience was disregarded, even though, shipyard provide clear evidence.On the contrary, experience of the owner was adopted without any evaluation.

  9. 1970s 1980s 1990s 2000s Tar Epoxy Tar Free Epoxy Modified Epoxy Epoxy 70~75 % Solid Volume Ratio 65~70 % 60~80 % Good Excellent Good Sea Water Resistance Poor Good Poor Heat/Chem. Resistance Good Excellent Good Edge Retention Abrasive Resistance Poor Poor Excellent History of WBT Paint Bituminous Tar Epoxy Tar Free Epoxy Shipowner’s experience are based on Tar Epoxy rather than Epoxy. However, Shipyard’s practice for epoxy coating have been developed for about 10 years. Modified Epoxy Epoxy

  10. Total soluble salt 83 mg/m2 NaCl 50 mg/m2 Issues of Salt limit ? • PSPC Requirement - Water soluble salts limit is equivalent to 50 mg/ m2ofNaCl or - Water soluble salts limit is 50 mg/ m2 • DE 49/WP.3 Reports of Working Group 16. The group……realizing that 30 mg/m2 of Cl- is equivalent to 50 mg/m2 of sodium chloride,the majority of the group agreed to the figure of soluble salt limit as 50 mg/m2 of sodium chloride. However, some delegations preferred to express the limit in terms of total soluble salts and preferred a level of 70 mg/m2. • Total soluble salt limit and NaCl limit

  11. Under film Corrosion Blistering vs. chloride level The results based on the 4,200 hr(6Months) of cyclic tests (NORSOK M-501) indicated that a maximum allowable chloride level of 70 mg/m2 (116 mg/m2 NaCl = TSS193 mg/m2) is recommendable as a critical value with some design margin. Recommendable Salt limit ? • Recommendable salt limit for coating performance (DE 49/6/7) • Manufacturer's Recommendation (DE49/INF.8) Total soluble salt 80 ~ 100 mg/m2

  12. Achievable Salt limit ? • Summary of Demonstration issued by DSME (22nd May, 2007) • Based on most of shipbuilders’ experiences, it can be said that TSS 50 mg/m2 for entire surface of the block is extremely difficult to achieve for shipyards according to the ISO 8502-6 and 8502-9. • Is there practical way to reduce the Salt level • Fresh tap water mainly took from river and contains some ions, and chloride is added for sterilizing purpose. In this reason, total soluble salt measured by ISO 8502-9 is about 30~ 40 mg/m2 on the uncontaminated surface after fresh water washing. • Salt level on floor of the block is increased after fresh waterwashing due to the accumulated salts and other components on the floor which are effect to conductivity after washing of the block.

  13. Total soluble salt limit 50 mg/m2 is extremely difficult to achieve for entire surface of WBT under the current shipbuilding environment unless otherwise washed with distilled water orcompletely protected the steel surface from salt contamination during construction. Achievable Salt limit ? • Total Coating Area of WBT of VLCC = 240,000 m2 ≈ about 40 Football Field

  14. Stripe Coating - Slat test : at least one / block - Inspection items in Table 1(dust, profile, cleanliness) Haw many, How to?? - Confirm primer material - Confirm thickness and curing of shop primer - Testing salt limit - Checking Contamination - Monitoring Cleanliness Steel Temperature, humidity and dew point shall be checked / recorded before PSP - Visual inspection for surface treatment and edge treatment PSP 2 nd Coating Shop Priming Erection Edge Preparation Surface Treatment SSP Erection Joint Coating 1 st Coating Damage Touch up Inspection for Inspection 6.2 Inspection Items

  15. Stripe Coating Surface Temperature, humidity and dew point shall be checked and recorded during coating - DFT measurements (Annex3) - Surface contaminant to be checked between main coats such as salt, dust, etc ? Surface Temperature, humidity and dew point shall be checked and recorded during coating - Visual inspection for surface treatment - Dust, Salt, etc, to be checked? PSP 2 nd Coating Shop Priming Erection Edge Preparation Surface Treatment SSP Erection Joint Coating 1 st Coating Damage Touch up Inspection for Inspection 6.2 Inspection Items Furthermore, Inspector may request additional test or inspection. But, Inspector have no authority to reduce the scope of inspection.

  16. Blast • Inspection • T/Up • Stripe Coat • Re-spray • (floor,etc) • DFT check • Re-spray • Final • inspection • T/Up • / Stripe Coat • 1st coat • 2nd coat • Touch up Effect of Excessive Inspection ▣ Typical WBT coating procedure of well organized Shipyards Normally two main coats are applied within two day in the indoor facilities where are controlled temperature and humidity.

  17. Blast, Dust, • Salt, Profile • Inspection • Blast • Inspection • T/Up • Stripe Coat • Re-spray • (floor,etc) • DFT check • Re-spray • Final • inspection • T/Up • / Stripe Coat • 1st coat • 2nd coat • Touch up Effect of Excessive Inspection ▣ Typical WBT coating procedure (After PSPC implemented) DFT Confirm for Weld line Record Temp. Humidity 2nd coat to be applied outside unless invested more indoor facility. Excessive inspections will not provide enhanced quality of coating !!

  18. DFT Measurement FWD WT BHD 3 ~ 6 m Long Spacing : 0.7 ~ 0.95 Typical Double Bottom Block

  19. : Flat area (1 reading / 5 m2) : Long & Trans(2 reading/2~3m) DFT Measurement Flat area : 22 Points Long & Trans. : 60 Points

  20. DFT Measurement • DFT measurement for Opening 26 Openings 12 Openings 8 Openings Total 46 Openings = 92 measurements Opening ≥400 mm = 4 measurements

  21. DFT Measurement Total Coating Area : 2,790 m2 Measuring Point / Compartment - Flat, Long.& Trans : min. 80 - Hole >10 mm : min. 90min. 170 points 5 4 x WT BHD 4.0 m 170 x 5 x 4 = 3,400 Total Measurement Points : 3,400 / Block Long Spacing : 0.85 m

  22. 10 m2 10 m2 10 m2 10 m2 10 m2 < 100 m2 100 m2 10 m2 10 m2 10 m2 10 m2 100 m2 100 m2 SSPC-PA2 • 5 separate spot measurements each 10 m2 A spot measurement(3 gauge readingsin 4cm dia circle) A gauge reading Total Measurement Points : 450 / Block Exceeding 100 m2 Not exceed 100 m2

  23. ≈1.1 Month for 3 Persons • Estimation of Required time for DFT Measuring • Estimation Assumption • Type of Ship : VLCC • Total coating area for WBT : 240,000 m2 • No. of measurement : about 0.5 / m2 • Required time for one measurement : 20 sec. for one gauge reading including calculation and reporting. • Working hours per day : 8 hours /day • Working days per month : 25 days /month Required Time : ② x ③ x ④ / 3600 / ⑤ / 3 persons = about 1.1 Month Effect of DFT Measurement - In case, opening means 400mm and above in diameter. - ( ) : Opening means all opening. - Tank boundary and complex areas are excluded.

  24. If h≤ about 2.3 m, scaffolding is not necessary for the coating h 2.3 m Scaffolding for Inspection • Additional scaffoldings are required for cross-up DFT measuring depending on the configuration of the block. • There are more chance for coating damage during DFT measuring and dismantling the scaffolding. h≤ 2.0 m for the DFT measurement

  25. APPROVED Eco-friendly System Immediately Checking DFT Virtual Simulation Various Type of Coating Simulator for Training of Coating If worker are skillful and quality level is high, Inspector may reduce the scope of inspection. It’s not allowed by the Rule !!! Only approved and qualified workers are doing the coating work.

  26. 100 80 60 Coating Quality level (%) Nobody sure remarkable quality improvement. But, only big cost increment is expected due to impracticality. 40 20 Initial Cost (USD) 0 Effects of PSPC • Cost will be rapidly increased over the coating quality level of blue line which is practically achievable quality level. • For about 5% levels up for quality, almost 100% of cost increment is expected as shown red line.

  27. (%) 100 80 Coating Quality level (Confidence level) 60 Inspection scope cannot be reduced depending on the shipyard’s quality level from now. 40 20 Inspection Cost (USD) 0 Effects of PSPC • In case of qualified shipyard, inspection cost is negligible as indicated by blue line. • Inspection cost of unqualified shipyard is extremely high as indicated by red line.

  28. Conclusions • The benefit of the enhancement of performance standard of coating is far less than expected upgrading the safety of ships. • More enhanced quality control does not always provide the quality improvement but provides only disturbing construction schedule and the quality level degrade. • For the correct implementation, authority and responsibility of each party to be clearly designated. • Industry guideline should be developed very carefully to minimized the confusion.

  29. Lesson and learn? Working together, Draw more big circle !!

  30. Q. A. Thank you!

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