YP4 1. TMCP YP4 1 2 YP4 2 YP4 YP4 NK 1 NK 2. 2.1 TMCP TMCP 198 HT TMCP Fig.1 TMCP HT 197 YP32 HT 2% TMCP YP32/36 198 7% 2 2% TMCP YP4 4kgf/mm 2 198 12 13 8. 1 ( 財 ) 日本海事協会 49 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 Application ratio of high tensile steels (w%) Ratio of each type of steel (w%) R & D for TMCP Technology R & D for TMCP Steels (YP32/36) R & D for TMCP Steels (YP4) Practical Application of TMCP Steels (YP32/36) Conventional Steels (YP32) Practical Application of TMCP Steels (YP4) TMCP Steels (YP4) TMCP Steels (YP32/36) Year Fig.1 Practical application of TMCP steels and transition of application ratio of high tensile steels 2.2 YP4 NK NK YP4 K 3 1987 M 4 1994 1998 1998 1999 C IACS WP/MW NK IACS UR IACS YP4 YP4 K NK 3. YP4 YP4 1986 NK YP4 YP32/36 Fig.2 2 ( 財 ) 日本海事協会 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 Investigated Ships Database for NK-Classed Ships Type of ship : Bulk Carrier (L 2m), Container Carrier (L 2m), Oil Carrier (L 2m) Shipyard : Shipyards adopting YP4 steels (7 companies) Year of build : 1986 (first adoption of YP4 steels) - 2 NK-Classed Large Ships (28 ships) YP32/36 : 16 ships YP4 : 93 ships Bulk Carrier (118 ships) YP32/36 : 9 ships YP4 : 9 ships Container Carrier ( ships) YP32/36 : 38 ships YP4 : 12 ships Oil Carrier (9 ships) YP32/36 : 68 ships YP4 : 22 ships 1st Investigation of Damaged Ships by Database for NK Damaged Ships Damaged Bulk Carrier (29 ships) YP32/36 : 13/9 ships YP4 : 16/9 ships Damaged Container Carrier (12 ships) YP32/36 : 12/38 ships YP4 : /12 ships Damaged Oil Carrier (16 ships) YP32/36 : 12/68 ships YP4 : 4/22 ships No additional investigation required 2nd Investigation of Damaged Bulk Carriers by NK Survey Records, focusing on Member A : Upper Deck Plate of Hatch Opening Corner Member B : Hatch Side Coaming End Damaged Bulk Carrier (14 ships) YP32/36 : /9 ships YP4 : 9/9 ships Out of investigation (1 ships) Detailed Investigation of the Damaged Members A and B by NK Survey Records (14 ships) Ship s age of first damage occurrence Shape of damaged members Steel grade and thickness of damaged members Damage distribution classed by cargo hold Heeding Points on Design and Workmanship for Large Bulk Carriers Fig.2 Flowchart of investigation on actual construction results and damages of large ships 3 ( 財 ) 日本海事協会 1 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 1 L 2m L 2m L 2m 2 YP4 7 3 1986 2 1999 Fig.3 Fig.4 Fig.3 YP4 1986 Fig.4 28 1 YP4 % Fig. YP4 YP4 4 3 2 1 NK-Classed Large Ships (7 companies) YP32/36 :16 ships YP4 : 93 ships Use rate of YP4 steels 1986 1988 199 1992 1994 1996 1998 2 Year of build Fig.3 Actual construction results of large ships classed by year of build 3 2 2 1 1 NK-Classed Large Ships (7 companies) YP32/36 :16 ships YP4 : 93 ships 118 ships 9 9 Bulk Carrier (L 2m) % ships 38 12 Container Carrier (L 2m) 9 ships Fig.4 Actual construction results of large ships classed by type of ship 68 24% 22 24% Oil Carrier (L 2m) 16 93 8 6 4 2 28 ships Use rate of YP4 steels (%) 36% Bulk Carrier Container Carrier Oil Carrier 3 2 2 1 1 Bulk Carrier (L 2m) YP32/36 : 9 ships YP4 : 9 ships 12 2 4 1 14 16 74% 7% 11 8% 1 7 64% 2 17% % 16 36% 9 A B C D E F G Shipyard Fig. Actual construction results of bulk carriers classed by shipyard 4 ( 財 ) 日本海事協会 2 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 4. YP4 3. Fig.2 1 NK 1 1999 2 3 YP4 Table 1 4 1 Fig.6 1 1 YP32/36 YP4 2% 2 YP32/36 3% YP4 3 198 YP32/36 YP4 1% YP4 MARPOL YP4 Table 1 Members investigated by NK database for damaged ships (1st damage investigation) Type of Member Code Example of Members UP Upper Deck Plate, Deep Tank Top Plate, etc. UG Deck Girder, etc. Upper Member UW Web Beam attached to Upper Deck Plate US Deck Longl., Deck Beam, Stiffener/Carling/Bkt. attached to Upper Deck Plate, etc. SP Side Shell Plate Shell Member ST Side Trans. SS Side Longl., Trans. Frame, Stiffener/Carling/Bkt. attached to Side Shell Plate, etc. LP L. BHD Plate, Deep Tank Side Wall Longl. Member Longl. Frame, Stiffener/Carling/Bkt. attached to LS BHD Plate Special Member HC Hatch Coaming, etc. 8 6 4 2 9 ships 38 ships 46 43 6 26 22% 27% 32% 12 ships 18% 13 16 12 12 12 YP32/36 YP4 steelsused Bulk Carrier (L 2m) 9 ships YP32/36 YP4 steelsused Container Carrier (L 2m) 68 ships Except damage of side longl. 22 ships 18 18% 4 YP32/36 YP4 steelsused Oil Carrier (L 2m) Fig.6 Results of 1st damage investigation by NK database for damaged ships 2% 2 1 29 YP32/36 13 YP4 16 Fig.7 YP4 ( 財 ) 日本海事協会 3 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 Upper Deck Table 2 Non-damaged members of large bulk carrier (2nd damage investigation) A Investigated members B Topside Tank : YP4 steels : YP32/36 steels (MS or YP4 steels partly used) Type of Member Deck & Shell Plate Internals Deck Plating Shell Plating Bottom Plating Longitudinals Non-damaged Members Stringer Plate in Strength Deck Strength Deck other than mentioned above Deck Plating exposed to weather, in general Sheer Strake at Strength Deck Side Plating Bottom Plating of TST Longitudinals attached to Plating mentioned above Upper Strake in Sloping Plate of TST adjoining to Strength Deck Fig.7 Investigated members of large bulk carrier (2nd damage investigation) 2 Table 2 Fig.8 A B A B 2 Fig.9 Nunber of ships Cross Deck Member A Upper Deck Plate of Hatch Opening Corner Fig.8 6 4 3 2 1 Crack Hatch Side Coaming Opening Member B Hatch Side Coaming End Cracked members of large bulk carrier (2nd damage investigation) Bulk Carrier (L 2m) YP32/36 : 9 ships YP4 : 9 ships 46 43 46 43 46 7 1 9 12 8 7 4 4 9 3 9 YP32/36 YP4 steelsused YP32/36 YP4 steelsused YP32/36 Crack (Other secondary members) (Member A, B) Fig.9 Results of 2nd damage investigation on bulk carriers 43 YP4 steelsused Member A Member B Member A and/or Member B. YP4.1 A 6 6 ( 財 ) 日本海事協会 4 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 Fig.1 2m 9 14 2m YP4 3 2 2 1 1.4L Fig.7 YP4 YP32/36 YP4 Fig.11 YP4.4L 2 3 8 7 8 Fig.12 NK Bulk Carrier (L 2m) (YP32/36 : 6 ships, YP4 : ships) 2~ Fig.1 (YP32/36 : 3 ships, YP4 : 9 ships) YP32/36 YP4 21~ 22~ 23~ 24~ 2~ 26~ 27~ 28~ Length of ship (m) Damage distribution classed by length of ship (Member A) Large Bulk Carrier (L 2m) YP32/36 : 21/9 ships 2 ships 19 ships 24 YP 4 : 4/9 ships 9 ships 4 ships Number of Hatch Opening Corners 2 16 12 8 4 YP32/36 ships YP4 ships Midship.4 L Damage ratio of hatch opening corner (Damaged corners / Total corners) 1% % % (YP32/36 steels damaged) (YP4 steels damaged) YP32/36 ships YP4 ships Aft No.9 No.8 No.7 No.6 No. No.4 No.3 No.2 No.1 Fore Fig.11 Damage distribution classed by cargo hold (Member A) 7 ( 財 ) 日本海事協会 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 YP4 6 8 4 Fig.13 9 NK.4L Fig.14 1.1 1.26 1 1% 11 Fig.1 Number of damaged ships 1 8 6 4 2 Fig.12 Stress concentration factor, Kt Thickness ratio of insert plate to upper deck plate 3.2 3. 2.8 2.6 2.4 Fig.13 1.3 1.2 1.2 1.1 1.1 1. 1. Bulk Carrier with damage (L 2m) YP32/36 : 2/9 ships YP4 : 9/9 ships Damage frequency of YP32/36 Damage frequency of YP4 ~ 2~ 4~ 6~ 8~ 1~ 12~ 14~ Ship's age of first damage occurance (years) Ship s age of first damage occurrence (Member A).2.2.1.1...9 1 2 2 3 3 4 Fig.14 Large Bulk Carrier (L 2m) YP32/36 : 21/9 ships YP 4 : 4/9 ships 2.2 Average Kt = 2.6 2..2.3.4..6.7.8 Stress concentration factor of hatch opening corner (Member A) Large Bulk Carrier (L 2m) YP32/36 : 21/9 ships YP 4 : 4/9 ships Ratio of corner radius to hatch breadth, r/b (2 ships) (9 ships) Parabolic / Elliptic Form (2 ships) (9 ships) Thickness of upper deck plate (mm) Locally increased thickness within midship.4l (Member A) (19 ships) (4 ships) Circular Form (19 ships) (4 ships) Damage frequency 8 ( 財 ) 日本海事協会 6 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 Hatch Opening Corner Cross Deck Design to be considered Lower stress concentration Fatigue strength outside midship.4l including torsion Workmanship to be improved Grinding of plate edge Prevention of notch Careful welding of slant plate Fig.1 Heeding points on design and workmanship for hatch opening corner.2 B 6 11 Fig.16 A Fig.17.4L Fig.18 2 3 2 2 1 1 Fig.16 Number of Hatch Side Coaming End Bulk Carrier (L 2m) (YP32/36 : ships, YP4 : ships) 2~ 24 2 16 12 8 4 Aft Fig.17 (YP32/36 : 4 ships, YP4 : 4 ships) YP32/36 YP4 21~ 22~ 23~ 24~ 2~ 26~ 27~ 28~ Length of ship (m) Damage distribution classed by length of ship (Member B) Bulk Carrier (L 2m) YP32/36 : 9 ships YP 4 : (YP32/36 steels damaged) (YP4 steels damaged) YP32/36 ships YP4 ships Aft part 9 ships Midship.4L Aft part side 4 ships 4 ships Midship.4L Fore part side ships ships Fore part Fore Damage distribution classed by cargo hold (Member B) 9 ( 財 ) 日本海事協会 7 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 6 1 12 11 Fig.19 Number of damaged ships 1 8 6 4 2 Fig.18 Fig.19 Bulk Carrier with damage (L 2m) Hatch Side Coaming Opening YP32/36 : 4/9 ships YP4 : 4/9 ships Damage frequency of YP32/36 Damage frequency of YP4 ~ 2~ 4~ 6~ 8~ 1~ 12~ 14~ Ship's age of first damage occurance (years) Ship s age of first damage occurrence (Member B) Toe end Design to be considered Soft-shaped toe Grinding of plate edge Prevention of notch.2.2.1.1.. Lower stress concentration Reinforcement Workmanship to be improved Careful welding of toe end part Grinding of weld toe Heeding points on design and workmanship for hatch side coaming end Damage frequency A B Fig.2 YP32/36 YP4 YP4 1986 1988 3 Light Weigt / Dead Weight Bulk Carrier (L 2m) (Member A and/or B) YP32/36 : 9 ships ( ships) (4 ships) YP 4 : 9 ships (9 ships) ( ships).18.17.16 YP32/36 ships.1.14 YP4 ships.13.12.11 1984 1986 1988 199 1992 1994 1996 1998 2 22 Fig.2 Year of build Weight ratio of bulk carrier with/without damage classed by year of build (Member A and/or B) 1 ( 財 ) 日本海事協会 8 平成 13 年度 ClassNK 研究発表会
実船における YP4 鋼の使用状況とその実績評価 6. YP4 1 NK 1 NK YP4 % 2 YP4 YP32/36 3 YP32/36 NK YP4 1 TMCP 4kgf/mm 2 (199). 2 837 (1999) pp.32-39. 3 K (1987). 4 M (1994, 1998). C (1999). 6 (1996). 7 (1981) pp.499-37. 8 146 126-1/1 (1998). 9 4 1983 pp.49-. 1 73 1987 pp.162-173. 11 No.21 (199). 11 ( 財 ) 日本海事協会 9 平成 13 年度 ClassNK 研究発表会