Risks of IACS Classed “Container Carriers” Change Class Notation to "General Cargo" that can carry High Density Break Bulk Cargo Including Iron Ore/Steel Products & Class Certification
SNAME Greek Section Presentation
By Eur. Ing. Peter D. Contraros C.Eng MRINA [Permanent Member of RINA’s Delegation at IMO] PDC Maritime S.A. Naval Architects & Marine Corrosion Consultants
c/o AP&A Ltd – 32, The Mall, London W5 3TJ E-mail: [email protected] Tel:+44 208 202 0573 Mob: +44 (0) 7866 459893 (UK) Mob: + 30 6942 42 3690 (Greece) Web Site: www.pdcmaritime.com
The study commissioned by the “American P& I Club” 1 Design Issues for Conversion of Container Ship into General Cargo Ship
• Regulatory Requirements • Stability [Intact & Damage] • Damage experience • Longitudinal strength [Buckling] • Structural behaviour when carrying high density cargoes (i.e. steel products or iron ore) • Unloading iron ore by grabs and mechanical shovels (bulldozers) • Application of IACS UR S26 S27 - Modified Ship • Dangerous Goods – limitations for the Modified Ship • Conclusions
2 Geometry Container Carriers –v– Bulk Carriers
3 Three Dedicated Container Carriers carrying Class Certificates as General Cargo used as a basis of the study
L = 190 m ≈ 2100 TEUs – DWT 34,000 B = 28.0 m Year of Built 1987, 1987 & 1989 D = 15.5 m/11.0m Changed to General Cargo Suitable to Carry Iron Ore
4 Class Notations Ship Types & related cargo densities
Bulk Carriers (as defined in SOLAS Ch. XII – CSR for Bulk Carriers) • BC-A (Max. Cargo density ≤ 3.0 t/m3) - max. tank top loading Iron Ore Alternate Holds and/or Iron Ore in Homog. Mode + GRAB(20) • BC-B (Max. Cargo Density ≤ 3.0 t/m3) - max. tank top loading Iron Ore in Homogeneous Mode + GRAB(20) • BC-C (Max. Cargo Density < 1.0 t/m3) • Number & size of steel coils on wooden dunnages for BC-A & BC-B • Flooding of each cargo applies • Damage & Intact Stability applies • Rate of ballast/de-ballasting over 600 tons/hour (about Handy size BC DWT=35,000)
Container Carriers • Maximum carrying Capacity of TEUs
General Cargo Vessels • Perhaps max. tank top loading • Number & size of steel coils on wooden dunnages • Damage & Intact Stability applies (new ships & SOLAS major conversions) • Rate of ballast/de-ballasting about 400 tons/hour (for GC of DWT=35,000) 5 SOLAS Ch. XII & IX Definition of Ships Carrying Heavy Bulk Cargoes
Bulk Carrier as defined in IACS Z11.2.2
2009 is also included by IMO as an additional ship shape for compliance with SOLAS Ch. XII
6 Definition of Homogeneous Loading Conditions – Definitions
Homogeneous Loading Condition
Highest filing 1.2 Then the Loading is NOT Homogeneous If the ratio of Lowest filing No Homogeneous [as per IACS UR S18.1] Loading Condition Highest filing Lowest filing
7 Container Carrier Changed Class Notation to General Cargo (Cert. issued by an IACS Class)
• Removal of Cell Guides • Approval of Intact Stability (IMO Res A.749(18)) & Loading Manual for carrying cargoes Homog. with max. S.G. 3.588 t/m3 or in another occasion approval for above for a single intern. voyage with iron ore cargoes with density of 1.5 t/m3 (DRI included). No damage (probabilistic) stability analysis requested by Class to be carried out • Checking / renewals of some hatch cover’s rubber packing but not testing required for wather-tightness as a General Cargo • Class Certificates issued stating that the vessel is General Cargo Carrier + Registry on behalf of Flag Admin. or Statement of fact that the vessel may carry ore from Venezuela to China –Without notifying the Flag Administration as a major conversion 8 Container Carrier converted to General Cargo Questions to be asked & Applicable Rules - Risk
• Is it considered Major Conversion as per SOLAS Ch-1 Reg. 1(b)? [a major maritime flag Admin. confirmed that is a Major Conversion]
• Intact & Damage stability required to be carried out for the anticipated loading including iron ore [Risk – if not carried out]
• Is Hatch Cover tested for weathertightness as per ICLL [Risk of fire – explosion – damage of cargo – flooding]
• What is the rate of loading and unloading as a function of ballasting & • de-ballasting capability of the vessel ? [Operational Risk]
• Is the vessel’s structure (local and buckling due to long. strength – increased GM) suitable to carry Iron Ore & steel products? [Structural Risk]
• Is the vessel capable to unload by GRAB & mechanical shovels (i.e. bulldozers)? [Structural Risk] 9 Comparison of two similar in geometry and size vessels with different scantlings
Dedicated Container Carrier Bulk Carrier BC-A [re-classed as General Cargo] [Iron Ore in Altern./Homog. Loading] Risk - Structural Damages of converted Container Carrier
31.0 EH36
L = 190 m
B ≈ 28.0 m
D = 15.5 m / 11.0 m
725 L = 180.0 m 31.0DH36
31.0 EH36 31.0 B ≈ 29.0 m
≈ 2100 TEUs 34.0DH36
Sp. 825Sp.
D = 15.0 m / 10.5 m EH36 34.0
12.0 DWT ≈ 34,000 DWT ≈ 34,000
24.0AH32
Max. Tank Top Load: 13.5 t/m2 2 23.5AH32 Max. Tank Top Load: 22.0 t/m
10.0
Spacing868 14.0
Iron Ore (Hom) S.G. 3.55 t/m3 3 –
Iron Ore (Hom) S.G. 3.0 t/m 810Spacing
Spacing 868Spacing
14.0 10.0 No GRAB Notation Mandatory GRAB(20) Notation
Not specified Steel Coils Steel Coils: 2 tiers of 1.6 m x15T/coil 20.5
on 3 dunnages Year of Built 1987 & 1989
Year of Built 2010 15.0AH32 12.0
15.5 •Spac. 845 22.5– Spac. 800 20.5
10 ≈12,000 1480 1780 ≈12.500 Bulk Carrier Loading in an Iron Ore Terminal Currently is reaching 12,000 tons per hour Vessel’s rate of ballasting & de-ballasting - RISK
11 Damage Experience of Vessel during loading while is de-ballasting – RISK
Not required by Class
See anything wrong???
12 Damage Experienced by M/V MSC NAPOLI caused by BUCKLING due to Hull Girder Strength - RISK?
Class’s Justification – As Quoted from MAIB Report:
”The classification rules applicable at the time of the vessel’s construction did not require buckling strength calculations to be undertaken beyond the Vessel’s amidships area“
PROBLEM EXAMINED WHILE SHIP AFLOAT NOT IN THE SEA BED
13 Increase of Dynamic Loading caused by High Density Cargoes
Increase of GM will result to: • Reduce the period thus increase accel. • Loads at Inner skin increased • Risk of damage of Inner Skin structure • Unsustainable acceleration at bridge (Human Risk)
14 Inner Bottom Plating of Container Carriers is not designed to carry Steel Products / Coils
Point Loads on I. Btm Plating & Stiffeners
15 Relaxation of weather-tightness applicable to Container Carriers and not to General Cargo Carrier & yet the ships certified to carry iron ore products - RISK???
2 heights of Superstructure 2 x 2300 = 4600 mm
.
4900
FBD Dk .
16 Hatch Cover & Coamings Risks against Weather-tightness
Container Carrier Bulk Carrier Hatch Coaming without compression bar Hatch Coaming with compression bar Risk – Weather-tightness not assured Minimal Risk – Cargo Damage & Explosion
Compression bar
Hatch Cover Closed
Compression bar
17 Typical of hatch covers of Container Carrier converted into General Cargo that may carry iron ore (including DRI) as Certified by IACS Class
Torn rubber packing at Expanding foam had been placed at side hatch cover panel of hatch panel prior to tightness testing
18 Uncertainties as per IACS Recom. 46 for Bulk Carriers – Risks for Cargo Ships?
DB Girders transfer the load to T. BHDs and then to Side Shell
IACS States: “It is recommended that high density cargo be stowed uniformly over the cargo space“
Asymmetric loading during Ballast Exchange
Coating in DB constantly suffered from mechanical damages starting from19 the 1st day of grab use IACS UR S1A Requirements Container vessel converted to BLOCK LOADING General Cargo suitable to (every two adjacent Holds Loading versus carry iron ore cargoes Homog. Draught)
Theoretical Explanation Theoretical Explanation Required Plate Thickness due to GRAB loading for a list of containers built around 80s - around 200 m in length – RISK?
22 A list of Bulk Carriers built between 80s - 90s and about 200 m in length - Limited Risk
23 Typical Unloading by 20 ton Grabs and Bulldozers – RISK?
Not required by Class for a General Cargo Carrier Major Operational Risk
24 Typical Cargo Hold of a KAMSARMAX B/C Unloading grain - Amsterdam’s Cargill Grain Terminal
>8 ton
25 DRI (fines) fire following contamination with sea water No weather-tight hatch covers will increase RISK
26 27 Carriage of DRI as per INTERCARGO
• DRI (A) Briquettes, hot moulded - Monitoring requirements
• DRI (B) Lumps, pellets, cold-moulded briquettes - Moisture < 0.3% - Hold must be inerted - Monitoring requirements
• DRI (C) By products - Moisture < 0.3% - Hold must be inerted
- Monitoring requirements 28
Positions of the Vents IACS UR S26 & S27
Fore Deck layout of the inspected ship Fore Deck of MV Derbyshire
29 Typical obstructions – Risk to damage from Grabs
Container Carrier w/o the Cell Guides Bulk Carrier with smooth surfaces with potential Risk to damages with minimal Risk to damages during unloading during unloading
Shelves + Container Fittings At T. BHD
30 Typical obstructions – Risk to damage from Grabs
Aftermost CH of a Container Carrier Aftermost CH of a Bulk Carrier
Shelves + Container Fittings At T. BHD Smooth Surfaces
Inner BTM
31 Typical obstructions – Risk to damage from Grabs
No. 1 Cargo Hold of a Container Carrier No. 1 Cargo Hold of a Bulk Carrier with with typical shelves for container stack clear surfaces for loading bulk cargoes
32 CONCLUSIONS
Conversion of a dedicated Container into General Cargo Carrier is a change of vessel type & as such, should be considered to be major conversion & satisfy the following: • Damage stability (probabilistic approach)
• Calculate Hull Girder Strength including Buckling as per IACS UR S11
• Prohibit to carry any form of DRI Ore
• Prohibit to carry any Iron Ore unless the Hull is strengthened for use of GRAB(20)
• Ballasting and De-ballasting should be controlled by prepared Loading Conditions 33 CONCLUSIONS (cont’)
• Class should address the Conversion as a “Major Conversion” (SOLAS) subject to the Flag Administration written agreement
• Heavy Density Bulk Cargoes like Steel Products / Coils should be approved by Class accounting for Dynamic Loading
• Trimming of Cargo is to be calculated and specified in the O.M.
• Hatch Covers are to be modified in order to maintain weather-tightness at all times – Small hatches and Vents fwd to comply with IACS UR S26 & S27
• Structure assessment for use of GRAB & mechanical shovels
• Minimise obstructions to avoid risks to stevedores damage 34
The Thinker by Rodin Originally designed to be Dante pondering the massive “Gate of Hell”
END
FORTHCOMING PRESENTATION ON
IMO BMP4 [BEST MANAGEMENT PRACTICE AGAINST PIRACY]
RECOMMENDED BEST MANAGEMENT PRACTICES ON THE USE OF NON-LETHAL MEASURES TO DETER BOARDING BY PIRATES
IMO CIRC\MSC\01\1337
• SUGGESTED PLANNING AND OPERATIONAL PRACTICES FOR OWNERS, OPERATORS, MANAGERS AND MASTERS OF SHIPS TRANSITING THE GULF OF ADEN AND OFF THE COAST OF SOMALIA
• RECOMMENDED BEST MANAGEMENT PRACTICES ON THE USE OF NON-LETHAL MEASURES TO DETER BOARDING BY PIRATES • Razor Wire • Coating Gunwales
• electrified barriers but are not recommended for hydrocarbon Watercraft immobilizing apparatus & system Use of Paravan Use of steel arms instead of steel arms