TABLE OF CONTENTS
1. INTRODUCTION ... 8
2. GENERAL ... 9
2.1 AXES CONVENTION... 9
2.2 DEFINITIONS, DENSITY AND UNITS... 9
2.3 DEFINITION OF TERMS... 11
2.4 ABBREVIATIONS... 14
2.5 GENERAL CONDITIONS... 15
2.5.1 Design responsibilities ... 15
2.5.2 Plans and specifications... 15
2.5.3 Materials, workmanship and Barge care ... 16
2.5.4 Weight control ... 21
2.5.5 Technical drawings and documents ... 22
2.5.6 Spare parts... 23
2.6 TESTS AND TRIALS... 23
2.6.1 General ... 23
2.6.2 Shore tests ... 24
2.6.3 Sea trials... 26
3. CLASSIFICATION, REGULATIONS AND FLAG STATE ... 27
3.1 CLASSIFICATION... 27
3.2 REGULATIONS, RECOMMENDATIONS AND STANDARDS... 27
3.3 FLAG STATE... 28 3.4 CERTIFICATES... 28 3.4.1 Plans, Notices ... 29 3.4.2 Registration... 29 4. DESIGN REQUIREMENTS ... 30 4.1 DESIGN TEMPERATURES... 30 4.2 NAVIGATION RANGE... 30 4.3 AUTONOMY... 30
4.4 LAUNCH OPERATIONAL CONDITION... 30
4.5 LOAD OUT OPERATION CONDITIONS... 31
4.6 TRANSPORT CONDITIONS... 31 4.7 DESIGN LOADS... 32 5. BARGE DESCRIPTION ... 33 5.1 MAIN DIMENSIONS... 33 5.2 GENERAL DESCRIPTION... 33 6. CONSTRUCTION... 36 6.1 HULL... 36 6.1.1 General ... 36
6.1.4 System of construction... 37
6.1.5 Bilge keels... 37
6.1.6 Skegs ... 38
6.1.7 Shell ... 38
6.1.8 Seawater inlet chests ... 38
6.1.9 Bulkheads ... 38
6.1.10 Tanks ... 39
6.1.11 Main deck ... 39
6.1.12 Hawse pipe... 39
6.1.13 Built in foundations ... 40
6.1.14 Local strengthening for jacket protrusion... 40
6.2 SUPERSTRUCTURES... 40
6.2.1 Barge access ... 40
6.2.2 Ventilation deckhouse... 40
6.2.3 Coamings ... 41
6.3 HULL EQUIPMENT AND OUTFITTING... 41
6.3.1 Barge’s name, Port of registry and Draught marks ... 41
6.3.2 Watertight doors ... 42
6.3.3 Masts ... 42
6.3.4 Hatches... 42
6.3.5 Chain locker ... 43
6.3.6 Railings and walkways... 43
6.3.7 Ladders and stairs... 43
6.3.8 Built on foundations... 44
6.3.9 Manholes and covers ... 44
6.3.10 Hoisting beams and lifting eyes ... 44
6.3.11 Raised floor... 45
6.3.12 Ventilation caps ... 45
6.3.13 Bollards and chocks... 45
6.3.14 Fendering ... 45
6.3.15 Towing appliances ... 45
7. LAUNCHING AND LOAD OUT SYSTEM ... 46
7.1 GENERAL... 46 7.2 SKIDDING MECHANISM... 46 7.2.1 Skidding units... 46 7.2.2 Diesel HPU ... 47 7.3 SKID TRACKS... 48 7.4 ROCKER ARM... 50
7.5 ROCKER LOCKING DEVICES... 50
7.6 HINGE POINTS... 51
7.7 ROCKER BUFFERING... 51
8. POWER GENERATION ... 52
9. BARGE OUTFITTING ... 54
9.1 MOORING ARRANGEMENT... 54
9.1.1 General ... 54
9.1.2 Temporary mooring... 54
9.1.3 Quayside mooring ... 55
9.1.4 Load out mooring ... 55
9.2 TOWING ARRANGEMENT... 55
9.2.1 General ... 55
9.2.2 Towing gear ... 56
9.2.3 Emergency Towing Gear... 56
9.3 WINDLASS... 57
10. OFFICE, CONTROL ROOM AND SWITCHBOARD ROOM... 58
10.1 GENERAL... 58 11. MARINE SYSTEMS ... 59 11.1 GENERAL... 59 11.2 BALLAST SYSTEM... 59 11.3 STRIPPING SYSTEM... 61 11.4 BILGE SYSTEM... 62
11.4.1 Main bilge system... 63
11.4.2 Bilge stripping system ... 63
11.4.3 Bilge water separator ... 64
11.5 FIRE WATER EXTINGUISHING SYSTEM... 64
11.6 FIXED CO2 FIRE EXTINGUISHING SYSTEM... 65
11.7 TANK AIR VENT SYSTEM & SOUNDING PIPES... 65
11.7.1 Tank air vent system ... 65
11.7.2 Sounding pipes... 66
11.8 POTABLE WATER / HOT WATER... 66
11.9 SEAWATER/ FRESHWATER COOLING SYSTEMS... 67
11.9.1 Main diesel generator sets... 68
11.9.2 Auxiliary diesel generator set... 68
11.9.3 Auxiliaries ... 68
11.10 COMPRESSED AIR SYSTEM... 69
11.11 FUEL OIL SYSTEM... 70
11.12 LUBRICATING OIL SYSTEM... 71
11.13 VENTILATION AND AIR CONDITIONING SYSTEMS... 71
11.13.1 Pump room and pipe tunnel ... 72
11.13.2 Engine room... 72
11.13.3 CO2-room... 72
11.13.4 Spare parts room ... 72
11.13.5 Control room and office ... 73
11.14 GREY WATER SYSTEM... 73
11.15 DIESEL ENGINE EXHAUST GAS LINES... 74
12. SAFETY SYSTEMS ... 75
12.1 FIRE FIGHTING EQUIPMENT... 75
12.1.1 Fixed CO2 system ... 75
12.1.2 Loose equipment ... 75
12.1.3 Deck wash ... 75
12.1.4 Insulation... 75
12.2 FIRE DETECTION SYSTEM... 75
12.3 FIRE AND GENERAL ALARM SYSTEM... 76
12.4 LIFE SAVING EQUIPMENT... 76
13. ELECTRICAL SYSTEM ... 78 13.1 GENERAL... 78 13.2 SWITCHBOARD/ MCC... 78 13.2.1 Switchboard S-C4101 ... 78 13.2.2 Distribution Panel S-C4601... 79 13.3 TRANSFORMERS... 79 13.4 380V AC MOTORS... 79 13.5 AC MOTOR STARTERS... 80 13.6 CABLES... 80
13.7 LIGHTING AND SMALL POWER... 81
13.7.1 Lighting ... 81 13.7.2 Emergency lighting ... 81 13.7.3 Navigation lighting ... 81 13.7.4 Small power ... 82 13.8 BATTERY SYSTEM... 82 13.9 SHORE SUPPLY... 82
13.10 CONTROL AND ALARM SYSTEMS... 83
13.10.1 General ... 83
13.10.2 Alarm & Monitoring System... 83
13.10.3 Control System ... 83
13.11 INTERNAL COMMUNICATION EQUIPMENT... 84
14. PRESERVATION SYSTEM... 85
14.1 GENERAL... 85
14.2 PAINT SYSTEM... 85
14.2.1 General ... 85
14.2.2 Surface preparation... 85
14.2.3 Under water part (Bottom and side shell up to 5 meter waterline) ... 85
14.2.4 Side shell above water (from 5 meter waterline) and rocker arm 86 14.2.5 Decks; exposed and interior... 86 14.2.6 Walls and underside decks; pump rooms, engine room and
14.2.9 Void spaces... 86
14.2.10 Office, control room and switchboard room ... 86
14.2.11 Outfitting ... 86
14.2.12 Miscellaneous steel ... 87
14.3 INSPECTION AND TESTING... 87
14.4 GALVANIZING... 87
14.5 INTERNAL CATHODIC PROTECTION... 88
14.6 EXTERNAL CATHODIC PROTECTION... 88
15. BARGE MAINTENANCE ... 89
15.1 MAINTENANCE EQUIPMENT... 89
15.2 HOISTING EQUIPMENT... 89
LIST OF APPENDICES
APPENDIX I DOCUMENT LIST
APPENDIX II OWNER FURNISHED EQUIPMENT LIST APPENDIX III VENDOR LIST
1. INTRODUCTION A has requested B
to perform a concept and a basic design for a steel jacket launch barge.
The barge will be designed as an unmanned, non-propelled steel deck barge for launching jackets up to 30,000 t. Load out and launching operations will be performed in the X area. In addition to launching operations the
barge will be used as transportation barge for miscellaneous items, such as topsides and process equipment.
It is the intention of this specification to provide a description, covering the design and technical requirements for the building, outfitting, testing and delivery of the Barge.
The specified data shall be verified by the Yard during the Detailed Design Stage. Reference is made to drawing 0240 DNC 01 001 Barge – General Arrangement – Plan.
2.1 AXES CONVENTION
The axes convention used in the project is presented in Figure 2.1.
Figure 2.1 axes convention
The origin of the system is as follows: • at APP: X positive to bow • at CL : Y positive to PS • at BL : Z positive upwards
2.2 DEFINITIONS, DENSITY AND UNITS
The units as used in this document are summarized in Table 2.1. Table 2.1 definitions and units
unit description definition SI
kn knot 0.514 m/s
Table 2.2 density
Seawater 1.025 t/m3
Lubrication Oil 0.90 t/m3
Marine Gas Oil 0.89 t/m3
The SI metric system shall be used as the primary means to describe physical quantities. Common commercial designations, when used in a descriptive manner not involving calculations, may be expressed in the customary units.
The following SI units, SI derived units and permissible non-SI units should be used in all drawings, specifications, etc.
Length meter m millimeter mm Time second s minute min hour h day d year y
Temperature degree Celsius °C
Volume cubic meter m3
Area square meter m²
Mass kilogram kg
metric ton (1,000 kg) t
Plane angle radian rad
degree ° or deg
Speed (velocity) meters per second m/s
Power Watt W
Angular velocity radians per second rad/s Acceleration meters per square second m/s²
Force Newton N
kilogram meter per square second kgm/s² load per unit length t/ m
Pressure bar bar
deck load per square meter t/ m2
Density kilogram per cubic meter kg/m3
metric ton per cubic meter t/ m3 Specific volume cubic meter per kilogram m3/kg Rate of flow cubic meter per second m3/s
cubic meter per minute m3/min cubic meter per hour m3/h
Electric current Ampere A
Electric voltage Volt V
Electric power VoltAmpere VA
2.3 DEFINITION OF TERMS
The following terms appearing in this specification shall be understood as stated here after:
The unmanned, non self-propelled launch barge, of which the design, technical requirements and construction details are defined in this specification and the accompanying plans.
The present specifications and accompanying plans and documents representing this design. The design shall be approved by Classification Society, China Classification Society.
Preparation of specifications and plans/drawings outlining the design and in sufficient detail to gain Class Approval. In terms of structural plans, for example, this relates to determination of the main scantlings.
Development of Basic Design into specifications, plans/ drawings that are Class approved enabling production of Barge. In terms of structural plans, for example, this relates to the development of fabrication shop drawings.
The company (Shipyard) to whom the building contract shall be awarded and who shall have responsibility for detailed design, construction, procurement, outfitting, testing and delivery of Barge, including all subcontracted work.
Any person or company engaged by Yard or a Subcontractor of any tier to execute a part of the work on behalf of Yard including any nominated, designated, named or preferred Subcontractor or supplier. Including those companies providing the Owner Furnished Equipment (OFE).
The Bureau under whose Rules, Regulations and Inspection the Barge shall be constructed and fitted out namely: CHINA CLASSIFICATION SOCIETY (CCS). Use of the word Class in this document implies the mentioned Classification Society.
The Shipping Inspection Bureau of the Country of Registry under whose Laws and Regulations Barge shall be registered, namely: CHINA CLASSIFICATION SOCIETY (CCS).
(Owner's Representative): Any person or persons or organization designated by Owner and to whom the authority and responsibility have been given to represent Owner in dealing with Yard for the purpose of fulfillment of the building contract. Manufacturer/Vendor:
Vendor is any firm or agent who manufactures or sells various materials, equipment and/or services used for the purpose of fulfillment of the building contract.
Owners Furnished Equipment (OFE):
OFE are all materials, equipment or services that will be supplied by Owner to Yard.
OFE is listed in "Owner Furnished Equipment List”, Appendix II of this specification, which will be part of the building contract. All items not mentioned in the list, but necessary for the proper functioning of Barge, will be provided by Yard.
Where the term "install" is used in relation to any material, equipment or coating, it will mean that those materials, equipment or coatings will be received, checked, stored, insured, handled, mounted on Barge and connected and tested by Yard, regardless whether the mentioned materials or equipment are supplied by Owner or by Yard.
Installation shall specifically take into account: (but not limited to)
• Configuration, weight, dynamic loading of the materials or equipment • Recommendations from Manufacturer
• Access for operation and maintenance
• Provision of Services, e.g., Ventilation, heating, cooling if required • Power supply, drainage etc. as required.
“Provide” or “Supply”:
Where the term "provide" or “supply” is used in relation to any materials or equipment, it will mean that those materials or equipment will be delivered by Yard, except for OFE (as listed in Appendix II), and installed in accordance with the fore-mentioned definition. Use of this term also applies to resources as far as necessary to comply with Yard's obligations.
Where the term "foundation" is used, in relation to any equipment to be installed in Barge, it will mean that Yard shall design, provide and install the necessary material to properly seat the equipment in Barge, including all and any work needed to transfer the static and dynamic loads into Barge’s structure and comply with the requirements of vibration suppression and equipment manufacturers. Main Deck:
Where the term “main deck” is used it shall refer to the continuous deck at 14.25 m above base line and assigned as the freeboard deck.
ABS American Bureau of Shipping
APP Aft Perpendicular
BL Baseline BOJ Bottom of Jacket
CR Control Room
CCS China Classification Society CL Centerline COG Center of Gravity DNV Det Norske Veritas
ER Engine Room
FPP Forward Perpendicular
GA General Arrangement
HPU Hydraulic Power Unit (or Pack) JLB Jacket Launch Barge
LCG Longitudinal Center of Gravity
LSW Lightship Weight
MBL Maximum Breaking Load MCR Maximum Continuous Rating MGO Marine Gas Oil
MOU Mobile Offshore Unit NDT Non Destructive Testing OFE Owner Furnished Equipment
PA Public Address
PS Portside PPM Parts per million
RPM Revolutions Per Minute SB Starboard SWL Safe Working Load
TCG Transverse Center of Gravity TOJ Top of Jacket
UPS Uninterrupted Power Supply VCG Vertical Center of Gravity
2.5 GENERAL CONDITIONS 2.5.1 Design responsibilities
The selected Yard shall have full responsibility for the Barge and its performance. 2.5.2 Plans and specifications
Plans and documents associated with this specification are listed in Appendix I. It shall be Yard's obligation to verify that construction, materials and equipment purchased by Yard will be compatible with the design embodied in these plans and specifications. If this is not the case, the plans and/or specifications are to be changed at Yard's cost and Yard is to obtain Class approval, if necessary.
In case of discrepancy between technical documents Yard shall notify Owner in writing for interpretation and direction.
Yard shall develop and is responsible to develop the Detailed Design on the basis of Basic Design supplied by Owner:
• Owner will supply plans and documents approved by Class corresponding to Basic Design.
• It shall be Yard's obligation to follow the Rules and Regulations listed in this Specification.
• In case of conflict between applicable Rules, Regulations and Conventions and Basic Design as submitted by Owner, Yard shall notify Owner in writing. The conflict will be treated in accordance with the Contract, and Yard shall accordingly supply the equipment and/or systems as derived from detailed engineering.
Should any part of the technical documents be in error or in conflict with any applicable rule or regulation, it shall be Yard's obligation to follow the concerning Rules and Regulations after notifying Owner in writing.
In case the technical documents have identified functional requirements, but some items or provisions have not been mentioned explicitly, it is Yard's responsibility to identify and supply these missing items and/or provisions at expense of Yard.
If some items are specified several times in the specifications they shall only be provided in the quantity as needed.
When and where special manufacture or trade names are mentioned it is understood that Yard has the option to use equivalent equipment, but not before written approval has been obtained from Owner, on any proposed alternative.
2.5.3 Materials, workmanship and Barge care
Yard binds himself to execute all the work according to the best practice of his industry to meet Contract requirements using the best method to ensure that Barge will be conform to the intended design. Maintenance of high standards of workmanship is also Yard's responsibility.
Yard shall be responsible for the performance of the Contract. Yard will do so in accordance with the intent of these specifications, including associated plans, despite any mistake, omission, discrepancy or lack of clarity in these specifications which should reasonably be apparent to an experienced Yard, upon a careful and critical study. This will also include those parts, which have not or can not be clarified by Owner at Yard's request prior to the starting of Contract. Yard shall be fully responsible for the Barge from signing of contract to final delivery upon satisfactory completion of all work, which forms part of this contract. Whilst in the hands of Yard Barge’s hull is to be earthed to a suitable point ashore, whether docked or afloat.
Yard will be responsible for the safe shifting, anchoring, mooring and docking of Barge and the supply of all the necessary facilities, services and equipment. Any associated cost will be to Yard’s account as part of the tendered Lump Sum Price. Equipment and Materials
Any license-built equipment shall conform to the original, including the latest improvements transferred by the original manufacturer at the starting date of the building contract.
Yard shall fulfill all responsibilities of any nature relating to the licenses, patents and rights covering Barge design, construction and equipment (restricted to Yard's supply).
Any machinery or equipment will be of standard-produced type, unless otherwise specified.
Before ordering any major item, material, machinery or equipment, Yard shall forward to Owner a written purchase specification for approval. Owner will return such specification as detailed in 2.5.2, bearing Owner's approval and/or remarks. Failing this, Yard may consider the Specification to be approved and place a purchase order after notifying Owner. In any case, one copy of each purchase order without price shall be submitted to Owner for his information.
Materials, fittings, furnishing equipment and outfit shall be new, undamaged and of first class marine offshore industrial quality as far as applicable.
All structural steel used for construction of Barge and machinery, including possible forgings and castings, shall be of shipbuilding and marine engineering quality, tested, inspected and certified as and when required by Classification Society and shall be physically and chemically in conformity with such requirements. All steel shall be free from cracks, lamination and similar defects. All structural steel plate and sections will be shot blasted and shop primed prior to any fabrication.
Timber shall be well seasoned, pressure impregnated, dried and reasonably free from knots.
All materials used in construction of Barge shall be acceptable to Inspector, Class or any other prevailing regulation. Asbestos shall not be used.
All equipment and major components shall carry permanent identification stamped-in, cast-on or engraved plate, showing manufacturer's name or trade name, model, serial number, size and type rating.
Where this identification is obscured Yard shall supply additional engraved plates of a standard design repeating this information, and permanently affix these plates in a clearly visible location.
Yard shall also permanently affix instruction plates engraved in both Chinese and English in all cases where original instruction plates have been obscured, have a text other than Chinese or English, have been omitted or give inadequate instruction for the service intended. In addition safety notices and notices pertaining to the well being of the crew must be provided in both Chinese and English text.
Instruments, gauges and metering devices must be supplied with all components calibrated in metric SI units.
Bolts, studs, nuts, capnuts, pins, hingepins, screws, hooks, etc. subject to corrosion, sticking or freezing in damp or exposed locations, shall be of stainless steel of a quality compatible with service conditions except where specifications state otherwise. Exposed threads from studded bolts shall be protected with capnuts to prevent damage to the threads.
Square threads may be approved for transport screws, but Whitworth threads shall not be used in any part of the construction.
Stainless steel fittings, if fitted, shall be electrically isolated from steel parts. Isolation shall be achieved by means of nylon strips or equivalent fitted between faces, nylon ferrules between rivets or bolts, to Inspector's approval.
Yard shall keep records of type, serial number and/or other identification of all material, equipment and component parts which shall be used in the construction or outfitting of Barge as part of Yard's contractual obligations.
Where Yard specifies equipment, proof of after sales spares and service facilities must be submitted to Owner for approval. This also applies to equipment items, which are offered as alternatives to those quoted within this specification as being Owner’s preferred supply.
Cleaning and preservation
Yard is to operate a “clean ship policy”. This assumes a state of general cleanliness will be maintained on decks and in internal compartments, including those that are to be permanently covered or which may become inaccessible. Rubbish and debris from work in hand are to be regularly removed. Oil or other liquid spillages shall be dealt with promptly in an approved manner.
Yard shall ensure machinery, equipment, assemblies, sub-assemblies, components, pipe work and tanks are cleaned and preserved as appropriate during all stages of manufacture, storage and trials until delivery to Owner.
Main and auxiliary engines, electrical and electronic equipment shall be protected in the period between shop tests and sea trials by vapor phase inhibitors or other method of inhibiting corrosion approved by manufacturers, Owner and engine manufacturer.
Machinery compartments and bilges shall be cleaned prior to sea trials and prior to delivery.
Barge is to be thoroughly cleaned to the satisfaction of Owner of all dirt and debris prior to delivery to Owner.
Yard will also bear the cost of the extermination of any insect or rodent infestation on completion of Contract.
Care is to be taken that no mechanical damage occurs to grit blasted areas on weather decks, when moving machinery or equipment.
Prior to any grit blasting taking place, Yard is to ensure that the area and its surroundings are free from flammable vapors or gases which may be ignited by sparks generated by the blasting process.
All vulnerable equipment, such as winches and hydraulic rams, and adjacent surfaces not subject to blasting, are to be protected from damage and the ingress
In general special attention shall be given to protect equipment against sand ingress e.g. when sealings are considered.
Yard shall undertake precautions to protect all finished flooring, sheeting, control boards, cables, piping with valves, instruments and other exposed equipment against damage.
During cold and/or wet weather and high humidity, Yard shall provide suitable protection, heating and ventilation as required to prevent deterioration of equipment and component parts.
All materials intended for or allocated to the building of the Barge shall be properly stored and protected from the environment, immediately upon arrival at Yard's site.
It is the responsibility of Yard to have an effective safety organization. Yard's safety representative(s) must liaise and discuss with Owner’s representative at a properly convened meeting as soon as possible before work commences at Yard’s works and draw up an agreed and clear ship/shore emergency plan. Suitable Barge and tank access procedures to be established and agreed by Owner and Yard.
Maintenance of watertight integrity and maintenance of safe moorings is the responsibility of Yard throughout Contract period.
For any ‘hot work’ (whether gas free or not) Yard is to provide a fire watch with the necessary instructions and equipment to prevent the outbreak of fire and to contain any resultant combustion. On completion of work the fire watch is to remain at the work site long enough to ensure that the area has reduced to a safe temperature.
Yard is responsible for the safe isolation and connection of fluid and electrical systems. This is to be achieved using “lock off” or “tag out” system to ensure that the isolation and de-isolation of systems is under positive control.
Yard is to take all necessary precautions to prevent contamination of any spaces, pipe lines, pumps or other equipment by any liquids or gases that might be contained anywhere on the Barge. Yard is to restore at its own expense any space and all equipment contained therein to its original condition should any contamination occur.
No transfers of fuel or water ballast will be performed during the building period without discussion and agreement between Yard and Owner. Fuel or water ballast shall not be transferred by means of any of Barge’s pumps, systems or pipelines while hot work is being performed on the deck, on the shell or internally
tanks and systems shall be restored to a certified gas free condition prior to work in them or adjacent to them being recommenced. It shall be the responsibility of Yard to maintain all certified gas free spaces in a gas free condition.
It shall be the responsibility of Yard to organize and undertake the safe and environmentally acceptable removal of all redundant materials from Barge in accordance with all the applicable rules and regulations.
All welding shall at least be in accordance with the requirements of Class. Welding shall be performed only by personnel who have successfully passed Class qualification tests for the type of welding they will be doing and have been regularly employed on such work for a minimum period of six months.
Individual operator's certificates shall be made available by Yard for inspection and approval by Owner.
It shall be Owner's prerogative to request the removal from the work of any welder that is not producing work of the required quality in Owner or Class opinion.
All welding shall be double continuous fillet in all areas unless noted otherwise and shall include all void spaces adjacent to the sea. Full penetration or partial penetration welds are to be provided where required and in accordance with Designer or Class requirements.
For all manual and machine welding, only electrodes on the "Approved Electrodes" listing, as issued by Class, and suitable for the particular application intended shall be used.
A planned program of NDT shall be carried out at Yard's expense and the results made available to Owner for approval. The program for NDT shall be approved by Owner and be in compliance with Class Standards. Additional NDT testing is required for all high stress areas.
In addition to Class requirements, pipe work fabrication/inspection shall be in accordance with Owner’s pipe work specifications.
Yard shall submit to Owner details of proposed welding sequences and procedures for approval. Special attention shall be paid to minimization of distortion and residual stresses due to welding.
All plate edge preparation shall be in accordance with Class requirements and all materials shall be free from rust, grease, slag or other harmful material at the weld joint.
moisture, wind and severe cold.
Yard will be expected to use the appropriate welding materials and welding procedures to match the steel to be welded.
Pre-heat, post-heat or special grade of steel requirements for any part of Barge structure, shall be strictly complied with by Yard throughout the work.
Operators of automatic welding machines shall have available for inspection by Owner a valid welding procedure for all plate thickness being assembled.
Manual welding shall be down-hand welding where possible and sections shall be turned accordingly.
All welding showing excessive irregularity, excessive convexity or concavity, "end-craters" or other defects out with acceptance criteria shall be rejected and shall be corrected in a satisfactory manner to Yard's account.
Yard shall provide an adequate number of trained and qualified welding supervisors so that welding operations can be properly surveyed at all times, including night work.
Lugs temporarily welded for positioning or mounting of permanent parts shall be carefully removed by flame cutting or gouging, re-welding if necessary and flush grinding followed by appropriate NDT to verify soundness of affected area. Exposed parts of finished products or installed equipment shall be adequately protected from damage.
2.5.4 Weight control
Yard shall set up a procedure for weight control for approval by Owner so that at the latest 45 days after acceptance of tender by Owner, Yard will be able to provide an estimate of Barge’s lightship weight and Center of Gravity (COG). For this Yard shall receive from Owner a list of weights of Owner Furnished Equipment.
The first weight estimates shall be compared with the result of the Basic Engineering and will be used as reference for the execution of the project.
During the construction of Barge, Yard will update the weight control and COG continuously for:
• Installed equipment, systems and structure to Barge • Installed steel sections, blocks and outfitting
• Design changes, if any
Weight control will end with deadweight survey and an inclining experiment to confirm lightship weight and COG, as per section 2.6.
2.5.5 Technical drawings and documents
Before construction commences, all drawings and/or calculations according to agreed list are to be submitted to Owner for approval. Number of drawings should be 5 copies (2 to site office and 3 for forwarding to Owner). Owner shall return one of every received drawing and/or calculation within 14 days from date of receipt (a maximum of 10 working days).
Yard will incorporate all remarks on the drawings made by Owner prior to commencement of the work. All changes in construction or equipment as a result of Owner's remarks are to be carried out when received within the 14 days limitation as stated above.
Yard at no expense to Owner will manage all drawings and/or calculations and documents, which require approval from CCS or a Regulatory Authority. Approval from Owner will not relieve Yard from the responsibility to satisfy any Regulatory Authority or Class, unless specifically agreed upon.
Documentation standard to be equivalent to that for Mobile Offshore Unit (IMO MOU Code 89).
Yard shall supply six (6) hard copies and one set of diskettes, CD or any other data carrier to be agreed between Owner and Yard of all drawings of Barge "as-built", to Owner.
Six (6) complete sets of documentation and instruction books covering all Yard-supplied equipment shall be handed over to Owner on delivery of the Barge. Furthermore a complete list of all supplied equipment and machinery items of the Barge, including recommended lists of spare parts for 2-years of operation and all piping installed in Barge shall be handed over in triplicate as well.
A preliminary stability booklet, complying with all the requirements to the approval of all relevant regulatory bodies, is to be submitted in triplicate by Yard to Owner for their approval, at least three months before delivery of Barge.
Results of the inclination experiment are to be included in the comprehensive trim and stability booklet, complying with all the requirements to the approval of all relevant Regulatory Bodies, for use by ship's officers with two copies for Owner.
Yard shall prepare an Operation Manual for Marine Equipment and Operations parts thereof in accordance with MOU CODE 89 including maintenance guide and shall incorporate Owner's part for any OFE in the deliverance of a comprehensive Operation Manual for submission to Class for approval. The Yard shall provide six (6) hard copies plus one (1) electronic copy to Owner on delivery.
2.5.6 Spare parts
Spare parts and maintenance tools based on Manufacturer's recommendations and as recommended by Class and as agreed with Owners will be supplied by Yard.
In addition Yard shall supply to Owner, manufacturer's recommended spare parts lists for 2 years of continuous operations in due time to ensure the delivery of such parts prior to Barge delivery.
All spare parts shall be properly protected against physical decay, corrosion and mechanical damage. They shall be clearly marked and adequately identified so that replacements can be ordered without difficulty.
Yard shall complete storage spaces on Barge in time to enable the positioning, labeling and listing of all spare parts (Yard- and Owner-supplied) prior to Barge delivery. Yard shall be responsible for handling and storage aboard Barge of all spare parts and all tools furnished by Owner as well as pieces and supplies.
Yard shall transfer any spares and tools received with equipment ordered by Yard to Owner.
2.6 TESTS AND TRIALS 2.6.1 General
Before Barge delivery to Owner all work performed by Yard shall be thoroughly tried out and tested to the satisfaction of Owner, Class and other regulatory bodies.
If any of the tests and trials does not demonstrate proper working and compliance with the specifications to the satisfaction of Owner and/or Class, the tests and trials shall be re-run at no additional cost to Owner until proper working and compliance with the specifications is obtained to the satisfaction of above mentioned parties.
Before conducting a test Yard shall give a minimum of 48 hours notice in writing to Owner of the time, date and place and type of test. If the test is delayed by Yard then the test will be required to be re-scheduled with the required 48 hour notice.
under Contract at any place where materials or part of the work is located or in preparation.
Yard shall keep a record of all tests and trials, whether performed by him or by Manufacturer's representative, and shall be responsible for recording all data such as temperatures, pressures, etc. at all stages.
Yard shall obtain from manufacturers all readings and data of various tests performed prior to installation, and these shall be forwarded to Owner.
Yard shall forward the following test results to Owner:
a. Manufacturer's test reports of all engines and machinery carried out before installation
b. Reports of all results obtained during shore trials c. Reports of all results obtained during sea trials
Yard shall prepare a comprehensive program for tests and trials and submit it to Owner and CCS for approval, one month before the planned start of the tests and trials.
Yard shall prepare a specification and planning for incorporation of tests and commissioning of both OFE and Yard furnished equipment.
Machinery and equipment tests shall be conducted at full load where practicable and these tests shall include OFE.
Before Barge is delivered to Owner the following tests and trials shall take place: • Shore tests
• Sea trials
Yard shall be responsible for the preparation and fulfillment of the shore tests and sea trials.
All materials, labor, tools, instruments, services, fuel, oils, glycol etc, as may be necessary to conduct these tests and trials, shall be furnished by Yard without charge to the Owner.
All tests and trials including the tests of Owner’s Furnished Equipment to be for Yard’s account, unless otherwise specified.
2.6.2 Shore tests
All work accomplished under this Specification including Barge main structure, main machinery, auxiliary machinery, piping, electrical, automation/control, ventilation and other systems shall be thoroughly tested during shore tests in order to demonstrate proper workmanship and suitability for the intended service
• NDT testing of all welded structures, repairs or modifications and pressure piping in accordance with requirements and the Owner Piping Specification. • X-ray tests of important welded seams (Owner and/or his supervisor can
require up to 100 photos in excess to those required by Classification Society)
• Hydrostatic testing of all tanks, cofferdams, piping systems etc
• Operational tests for doors, access hatches, anchor winch, retrieval winch, ventilator enclosures, capstans and flaps
• Operational tests for all watertight closures and transits • Operational tests for fire water and CO2 systems
• Operational and load test diesel generator units • Operational tests for all control and alarm systems • Operational tests for all piping systems
• Operational tests for valve remote control panel, emergency stop and closing plant
• Operational test of remote tank level indication plant • Operational test of ventilation and noise level protocol
• Operational tests for water- and electrical heating systems, incl. lay-up condition
• Protocol of electro magnetic disturbance measurements
• Protocol of air gap measurements in generators after installation
• Operational tests for the whole electric plant including tests with parallel running generator, reverse power, under voltage, overspeed, etc.
• Operational tests for skidding systems
• Operational tests for the ballasting and shipping systems • Shore supply
Where all these tests cannot be successfully completed in harbor due to physical limitations, then the tests are to be performed during sea trials and shall be added to those described in section 2.6.3.
All tanks forming an integral part of the hull shall be tested by water pressure in accordance with the requirements of Class. Adjacent compartments shall not be tested simultaneously. The ballast system shall be used during the ballast tests to demonstrate satisfactory operation.
All piping will be pressure tested. Pipes for lubricating oil, fuel oil, hydraulic oils, water and air, will be cleaned according to Manufacturer’s and/or Owner’s requirements and yard standard for pre and post pressure testing. All pipeline systems and associated valves, and ventilation systems to be fully tested.
The electrical system will be tested for several loading conditions including single and parallel running of the generators. 100% load and overload will be tested to the satisfaction of Class. Before testing the total electric plant will be megger tested and figures will be presented to Owner.
During the shore tests, when Barge is essentially complete, an inclining experiment shall be conducted at the minimum possible draft in accordance with the regulatory bodies' rules to establish Barge’s LSW and COG.
2.6.3 Sea trials
When Barge is near delivery and is suitably equipped, sea trials shall be conducted to fulfill Class, regulatory bodies' and Owner's requirements. Yard is to prepare a loading condition and a sea trial program, which is to be submitted to Owner for their approval.
In addition to the standard tests, required by Class and Flag State, Owner will require at least the following tests to be carried out in deep water.
• Anchoring test
• Machinery control tests including test for unmanned machinery • Ballasting sequences
Fuel consumption will during all trials be recorded as a function of produced power and as a function of time during the trials. This to enable Owner to determine fuel consumption on a daily basis.
Yard shall submit to Owner and Class the proposed location for the sea trials for approval.
3. CLASSIFICATION, REGULATIONS AND FLAG STATE
Vessel including machinery, equipment and outfitting will be constructed under supervision of China Classification Society to obtain class notation. The barge will be classed as an unmanned, non self propelled, steel deck barge. In addition to the CCS Rules, the JLB will comply with applicable ABS Rule requirements.
The class notation of the barge will be:
3.2 REGULATIONS, RECOMMENDATIONS AND STANDARDS
The following Rules and Regulations will be included, but not limited to:
• CCS Rules and Regulations for the Construction and Classification of Sea Going Ships 2001
• Hull – Volume 2, Part 2 – Chapter 1 to chapter 4 and chapter 12 (Shell plating according chapter 2)
• Machinery – Volume 3, Part 3 • Electrical – Volume 4, Part 4
• Technical Regulations for Statutory Survey of Ships and Installations– Non International Voyage Ships
• Life-saving equipment: Chapter 2, Part 4, Section 2.14(2)
• Stability during Launching: Chapter 7, Part 4, Section 1,2 & 3.10 • ABS Rules for Building and Classing Steel Barges 2003
• ABS Rules for Mobile Offshore Drilling Units for direct structural calculations • CCS Guidelines for direct analysis of oil tankers – January 2003 – section 9,
for (buckling) strength of bulkheads and decks
• DNV Classification note 30.1 – Buckling strength analysis – 1995
• The International Convention on Load Lines 1966, revised by the protocol of 1988, consolidated edition 2002
• International Convention on Tonnage Measurements 1967/1969
• International Convention of the Prevention of Collisions at Sea 1972 incl. amendments
• International Convention for the Safety of Life at Sea SOLAS 1974, Protocol of 1988 including 2000 Amendments
• Guidelines for Safe Ocean Towing – MSC/ Circ. 884 – 21 December 1998 • Technical Regulations for statutory survey of Ocean Towing 1999,
promulgated by the Register of Shipping of People’s Republic of China CSA 5/5 (LAUNCH) BARGE
• International Convention of the Prevention of Pollution from Ships (MARPOL) 73/78, Consolidated Edition, IMO 1997
• IMO Regulations (not limited to)
• IMO Resolution A.468 - XII – Noise Control
• IMO Resolution A.749(18) – Intact Stability, Pontoon Barge
• International Electronical Commission (IEC), Electrical Installation in Ship, Publication no. 92
• IACS Recommendation 47 – Shipbuilding Repair and Quality Standard • ANSI Standard
3.3 FLAG STATE
The flag state of the JLB will be the People’s Republic of China.
The following certificates or provisional certificates and protocols shall be furnished at delivery of Barge:
To be issued by Class / Flag Authorities and/or Regulatory Bodies (Yard to include price in Lump Sum tendered):
1. Classification certificate of Barge 2. Safety construction certificate 3. Load line certificate
4. International tonnage certificate 5. Stability compliance certificate 6. Safety equipment certificate 7. Oil record book
8. International oil pollution prevention certificate 9. Fitness for towing certificate
To be issued by Yard's Vendors (for Yard's supplied equipment only):
1. Certificates of pressure Vessels, incl. relief valves, hull valves, fuel tankvalves and other as required by CCS
2. Explosion proof equipment certificates or industrial safety certificates 3. Navigation equipment certificates (compasses and lanterns)
4. Safety and marine equipment certificates
5. Towing, anchoring and mooring equipment certificates 6. Certificates of materials used in hull construction
To be issued by Yard:
1. Yard's certificate of Barge
2. Protocol of delivery and acceptance 3. Protocols of tests and trials
4. Declaration of warranty
5. As-built plans, data and calculations
6. Operation manual (including lay-up and start-up instructions) 7. Inclining test report
8. Trim and stability booklet 9. Noise and vibration report
10. Safety Information and Instruction Notices 11. De-rat certificate
3.4.1 Plans, Notices
• Yard to provide capsulated plans for bulkhead mounting of the following plans according to Regulatory requirements :
• General Arrangement • Fire Fighting and Safety
• Tank and Capacity Plan and Sounding Tables (including corrections for heel and trim)
• Yard to provide safety signs, notices and exit markings in accordance with Regulatory requirements.
These are all to be in the English and Chinese language. 3.4.2 Registration
Registration will be dealt with by the Owner, but Yard shall provide all necessary assistance to Owner to obtain the maximum reduction for net and gross registers tonnage including deduction for permanent ballast spaces.
4. DESIGN REQUIREMENTS
4.1 DESIGN TEMPERATURES
• Ambient temperatures -20°C – +45°C • Water temperature -2°C – +30°C
• Humidity 55% Relative Humidity @45°C
The mechanical ventilation systems shall be designed for an outside air inlet temperature of +40°C.
4.2 NAVIGATION RANGE
Navigation range of the barge for transport will be unrestricted ocean service.
The barge tank capacities will be suitable for a normal load out, transport and launch operation of 60 days. Tank layout will ensure power functionality for trim angles up to 10 deg by stern.
4.4 LAUNCH OPERATIONAL CONDITION
The maximum (environmental) launch condition data is: • Maximum jacket weight 30,000 t • Maximum 30,000 t jacket VCG 33.4 m • Minimum 30,000 t jacket Length 200 m
• Wind speed (Vw) 13.8 m/s
• (Surface) Current speed (Vc) 2.0 kn
• Significant wave height (Hs) 2.1 m
• Peak Period (Tp) 8.0 - 9.0 s
• Maximum scantling draught 38.0 m at APP • Maximum trim (incidental) 12.0 deg • Maximum trim (operational) 10.0 deg
The barge shall be positioned with the bow into the waves during launching operation.
4.5 LOAD OUT OPERATION CONDITIONS
The load out operation is limited by the following data, based on enlarged skid track height at the different quays to 3,500 mm and a JLB skid track height of 2,000 mm above main deck
The following limits are applicable:
• Minimum water depth in a tide cycle 4.7 m • Maximum distance quayside skid track to water level 12.3 m
• Maximum Draught 11.75 m
• Scantling Draught 12.25 m
• Allowable tide variation 7.1 m
• Maximum tide variation speed 1.0 m/h
With the dimensions of the barge determined in the Concept Design and the above limits load out will be feasible at the two intended load out yards with the enlarged skid track heights presented in Table 4.1. The corresponding draughts of the barge are presented in the table as well.
Table 4.1 yard skid track height and required draught variation Skid track height Required Draughts
Chiwan 3,500 mm 8.45 11.75 m
Zhan Jiang 3,500 mm 6.25 11.37 m
4.6 TRANSPORT CONDITIONS
The environmental data used for motional calculation representing a 10-years storm condition in the South China Sea area is presented based on Noble Denton “Guidelines for Marine Transportation”; the design storm for the towage should be the 10 year return period monthly extreme storm for the towage route.
Based on the above mentioned Noble Denton guideline and Global Wave Statistics of the South China Sea area (Area b2), the following conditions are applicable during transport:
• Significant wave height (Hs) 8.5 m
• Peak Period (Tp) 10.5-16.0 s
• Peakedness factor (g) 2.7 -
Reference Document 0240 CNC 01 011 Barge – Motion Analysis – Transport Report
4.7 DESIGN LOADS
The resulting design loads derived from all operational conditions are summarized in Table 4.2.
Table 4.2 Design Loads
Scantling draught forward 12.25 m
Scantling draught aft 38.0 m
Deck load - cargo deck area 15.0 t/m2
Deck load - deck area forward (175 m from APP to FPP) 10.0 t/m2 Total Bending Moment (Rule Value - unrestricted) 716,600 tm
Rocker Arm Load 10,500 t
Rocker Arm Load – Load per unit length 840 t/m
Skid Beam Load – Pressure 2,540 kPa
Skid Beam Load – Load per unit length 330 t/m
5. BARGE DESCRIPTION
Reference is made to 0240 DNC 01 001 Barge – General Arrangement – Plan.
5.1 MAIN DIMENSIONS
The main dimensions of the barge shall be:
• Length Overall (approximately) 235.00 m • Length between Perpendiculars 215.00 m • Breadth moulded 52.50 m • Depth moulded 14.25 m • Typical Transit Draught 6.50 m • Block coefficient (approximately) 0.96 - • Scantling Draught (forward) 12.25 m • Design load line draft 10.45 m
5.2 GENERAL DESCRIPTION
The Barge shall be an unmanned, non self-propelled steel deck barge designed for launching steel jackets weighing up to 30,000 t and up to 300 m total length. Besides for launching operations the barge will be used for transportation purposes with maximum cargo load capacity of 60,000 t.
For launching purposes two (2) skid beams including skidding equipment as well as two rocker arms, hingeable at the stern, shall be provided. The beams and rocker arms shall be adjustable in between positions from 8 to 14 m from CL. The Barge shall be equipped with suitable towing gear, including emergency towing gear, as well equipment to handle this gear. Also a single anchor system for temporary mooring shall be provided.
The Barge shall be subdivided into watertight and non-watertight compartments by means of transverse and longitudinal bulkheads.
A double bottom shall be under the engine room to accommodate the fresh water cooling tank. A double bottom shall be provided under both pump rooms as well. These double bottom sections shall be void. The pump room forward shall be closed with watertight doors forward and aft and the aft pump room shall be closed with a watertight door at the forward bulkhead of the pump room.
The general arrangement below main deck shall comprise: • Forepeak Water ballast tank
• Anchor recess
• Anchor chain locker including access cofferdam • Central store
• Rope store
• Office spaces, meeting room and changing room (upgradeable to pantry, accommodation and washing room)
• Control and switchboard room • Battery room and electrical store • Engine and Auxiliary room • CO2 room
• Spare parts store • Workshop
• Fresh Water cooling tank in double bottom • Escape trunk (from Control Room)
• Various tanks, comprising • Fuel Oil tanks • Lube Oil tank • Grey water tank • Bilge water tank • Sludge tank • Hydraulic Oil tank • Potable Water tanks • Pipe tunnel (in three sections) • Forward pump room
• Aft pump room • Water ballast tanks
On main deck the following shall be allocated:
• Towing and emergency towing arrangement including retrieval equipment • Navigation lights
• Anchor windlass, combined with bridle retrieval winch and including warping head
• Skidding and Launching Equipment • Life saving equipment
Figure 5.1 General Arrangement – Side and Top view
For the General Arrangement of the Barge reference is made to the following drawings:
• 0240 DNC 01 001 Barge – General Arrangement – Plan • 0240 DNC 01 003 Barge – Machinery Spaces – Arrangement • 0240 DNC 01 004 Barge –Pump Room Aft – Arrangement • 0240 DNC 01 005 Barge –Pump Room Forward – Arrangement
6.1 HULL 6.1.1 General
The construction plans associated with these specifications shall be approved by the Classification Society. The construction of the Barge shall be in compliance with the applicable Rules and Regulations, as set out in Section 3 of this document.
Scantlings of structural members may be adapted to Yard's practice, however due consideration shall be given to the required section modulus and overall strength. It is not allowed to change the principal construction layout.
The Barge shall be subdivided into watertight compartments by longitudinal and transverse watertight bulkheads.
6.1.2 Main subdivision
The hull shall be divided in tank sections by eight (8) transverse watertight bulkheads. The bulkhead at frame 80 shall be a collision bulkhead. Tank lengths shall vary between 25m, 35m and 40m and forepeak tanks shall be 15m. Pump room lengths shall be 15m and machinery and service spaces area will be 25 m in length. All bulkheads shall be placed on webframe distance.
Two longitudinal watertight bulkheads at 15,000 mm from CL shall run from APP to FPP. On CL a bulkhead shall be provided between frames 0 and 10 as well as frame 80 to 86 (aft tank and forepeak tank). Between frames 10 and 80 a 9,000 mm wide pipe tunnel shall be provided by means of longitudinal bulkheads at 4,500 mm from CL.
Between frames 70 and 80 the machinery and service spaces shall be located, provided with a tween deck, division bulkheads and inner bottom of 1,500 mm high. Inner bottom shall be the tanktop of fresh water cooling tank. The space shall extend to the two outer bulkheads.
Two (2) pump rooms shall be located in between frames 20&26 and 50&56 and shall extend to the two outer bulkheads. Large openings in the pipe tunnel bulkheads shall be provided for accessing the pump room without compromising longitudinal strength. The pump rooms shall be provided with a inner bottom of 1,500 mm height.
The rest of the compartments shall function as ballast tanks. Other tanks shall be arranged in the machinery space.
Figure 6.1 General Arrangement – Subdivision 6.1.3 Material
The barge shall be constructed of all welded shipbuilding quality steel in accordance with the Requirements of the Classification Society. Mild steel with yield stress of 235 N/mm2 Shall be used as far as possible.
In bottom and deck higher tensile steel with yield stress of 315 N/mm2 shall be applied.
In the stern section higher steel grades may be considered, however never exceeding the maximum allowed steel grade E36.
The skid beams and rocker beams shall be made from steel E36 or D36. 6.1.4 System of construction
A longitudinal framing system shall be applied. The longitudinal stiffeners shall be supported by transverse bulkheads and web frames. The web frames shall be supported by longitudinal bulkheads. For the stiffeners standard bulb profiles or alternatively constructed members for stiffening shall be used.
Main transverse (web) frame spacing shall be 2,500 mm.
Transverse bulkheads shall be stiffened vertically, with three (3) horizontal girders to support the stiffeners.
6.1.5 Bilge keels
The parallel midship section part of the barge from frame 13 to frame 67 shall be fitted with bilge keels. Bilge keels shall be welded on a flat bar of 60x20 mm, web shall be 230x20 mm and at the tip a round bar of 50 mm shall be fitted.
Two skegs underneath the bottom plating at the aft ship in line with the outside longitudinal bulkheads shall be provided.
The plating of bottom and side shell shall be reinforced in way of openings and appendages as required by the Classification Society.
Shell plating in way of the anchor shall be increased by 4mm in thickness down to the light water line.
6.1.8 Seawater inlet chests
Six (6) large sea chests will be provided for supply of ballast water and will ensure a fast ballast intake during load out and launching operations. In proximity of each pump room a low and high sea chest will be provided and two low sea chests will be provided on the aft end of the pipe tunnel.
Furthermore a high and low sea chest for machinery consumers will be provided as required.
Each sea chest shall be provided with galvanized steel plate gratings bolted to the shell and be equipped with a compressed air and vent pipe connection.
A watertight collision bulkhead shall be located at frame 80. The other watertight transverse bulkheads shall be located at: frame 10. 20, 26, 40, 50, 56, 70 and frame 80. The following subdivision shall be provided by the bulkheads:
APP to fr10 (Aft peak) Ballast tanks fr10 to fr20 Ballast tanks, pipe tunnel fr10 to fr26 Ballast tanks
fr20 to fr26 Ballast tanks, aft pump room fr26 to fr40 Ballast tanks, pipe tunnel fr40 to fr50 Ballast tanks, pipe tunnel fr40 to fr56 Ballast tanks
fr50 to fr56 Ballast tanks, forward pump room fr56 to fr70 Ballast tanks, pipe tunnel
fr70 to fr80 Ballast tanks, machinery spaces, various tanks, stores, workshop, control room and office
For longitudinal bulkheads reference is made to section 6.1.2. 6.1.10 Tanks
The arrangement of the tanks and their capacities shall be as be as indicated in the drawing 0240 DNC 03 001 Barge – Tank and Capacity – Plan.
Drain plugs shall be provided at the bottom each tank. At least two (2) plugs shall be installed at opposite corners. Tanks shall be accessible through at least two (2) manholes with flush water tight covers and steel ladders with safety cages and platforms.
All structures shall be constructed with continuous welding. Bottom and top stiffeners in tanks shall be provided with lumber holes for drainage purposes and to avoid trapping of air.
6.1.11 Main deck
The main deck shall be straight over the entire length of the Barge, without sheer or camber. At the aft part of the Barge two (2) inclined deck sections shall be provided in way of the allowable rocker beam positions. Rounder corners shall be applied at sheer strake in a gun whale.
The main deck shall be the freeboard deck.
The main deck shall be constructed for a deck load of 15 t/m2 for the deck area from APP to frame 70. The deck load for the deck area forward of frame 70 shall be 10 t/m2. Adequate stiffening shall be arranged under and around ventilators, openings, hatches, etc.
Large recesses in main deck shall be provided for accommodating the rocker arms at the stern. Recesses shall be provided for bollards and chocks as well. The main deck forward and aft shall be locally reinforced in way of the capstans, bollards, shocks, etc.
6.1.12 Hawse pipe
A hawse pipe shall be provided for the anchor and shall have sufficient slope for anchor to slide out by gravity.
An anchor pocket of fabricated steel construction shall be provided in the stem structure, sufficient to house the anchor leg, locking and tightening devices on the chain stopper.
6.1.13 Built in foundations
Where required the decks shall be reinforced to take the loads of the equipment. The built-in foundations shall be able to withstand the forces due to Barge motions, vibrations and forces of the machinery.
6.1.14 Local strengthening for jacket protrusion
To allow for protruding jackets the forepeak of the Barge shall be strengthened. Transverse bulkheads shall be added at frame 83, 84 and 85 and the plating of the longitudinal bulkheads shall be suitably increased.
Reference is made to 0240 CVC 10 003 Barge – Local Strength – Calculation Report and 0240 DVC 01 043 Barge – Transverse Sections and Bulkheads – Forepeak – Basic Construction Plan.
6.2 SUPERSTRUCTURES 6.2.1 Barge access
The barge shall be accessed through a small enclosed structure near CL, closed with a watertight door. The access housing shall be located above the machinery space and combined with a ventilation deckhouse (refer to section 6.2.2). The structure shall be 2,200 mm in height.
The access superstructure shall start between frame 79 and frame 80 and be approximately 2.5 m long and 9.0 m wide. Watertight access door shall be provided at the aft side of the superstructure.
A second entrance from main deck shall be provided from a small superstructure at the aft side of the machinery spaces for emergency escape.
6.2.2 Ventilation deckhouse
Deckhouses shall be placed on the main deck with fan rooms to provide ventilation inlet and outlet for generator room and other spaces under the main deck and accommodate the electrical fans for mechanical ventilation. Furthermore two separate sections of the Barge access superstructure shall accommodate generator room exhausts as well.
Deck houses shall be 2,200 mm in height and 5,000 mm wide. All openings shall be ventilation louvres with watertight fire covers and not be located below 900 mm from main deck. Access hatches shall be provided in roof of each deckhouse.
The following fan rooms shall be provided:
• fr66 to fr67 – ventilation exhaust for pump room and pipe tunnel • fr68 to fr70 – ventilation supply for pump room and pipe tunnel
• fr70 to fr75 - ventilation supply engine and auxiliary room, minus 1,250 mm wide emergency access and escape structure
• fr75 to fr76 - ventilation exhaust engine and auxiliary room • fr76 to fr77 – trunk for generator exhaust lines
Coaming shall be provided around the tank access lines at main deck, e.g. fuel oil tank lines, sludge draining, fresh water filling line.
The height of coamings shall be in relation to the position of the fans, the degree of water tightness and the degree of hazardous area, according to Classification requirements, as indicated on GA.
The plate thickness shall be in accordance with the Classification Society.
6.3 HULL EQUIPMENT AND OUTFITTING
6.3.1 Barge’s name, Port of registry and Draught marks
The name of the Barge shall be placed on both sides in 1,000 mm high characters and on the stern name in 450 mm high characters and port of registry in 300 mm high characters.
Characters, numbers and marks in general shall be cut from 6 mm plates and welded on with continuous welding and painted in a contrasting color.
Draft marks, shall be tack-welded and painted on both sides fore, aft and at mid ship of the Barge. Draft marks shall be 100 mm in height and shall be placed every 200 mm. Freeboard marks, size and location shall be according to Authorities.
Yard’s sign with engraved yard No. and year of delivery is to be mounted on the access deckhouse.
On both sides and on main deck the position of transverse bulkheads and tank markings shall be marked; frame numbers and tank numbers shall be tack welded and painted.
Manhole covers shall have tack welded and painted numbering. On the bottom plating, tank plug numbers shall be tack welded.
6.3.2 Watertight doors
The entrances giving access to machinery space below main deck level shall be fitted with a steel watertight door of the hinged and dogged type with manual operation. Manual check valve, to verify the compartment is not flooded, shall be fitted in the watertight bulkhead next to the watertight door.
Below the freeboard deck watertight closures are to be provided for every opening through any watertight boundary as indicated in the drawing 0240 DNC 03 003 Barge – Watertight Subdivision – Plan.
On the bow one (1) foldable mast shall be provided. All signaling lights, day signals and Halyards as required, shall be fitted to this mast. A battery shall power the navigation lights. The mast shall be placed on a raised platform to enable passing of the bridle retrieval wire.
One (1) mast shall be provided on the aft with a battery powered yellow navigation light, in accordance with CCS requirements. The mast shall be divided in two, separated by a bolt secured flanged connection. This connection provides easy removal of the mast during a launching procedure.
Six (6) escape hatches shall be provided as indicated on general arrangement plan, four (4) shall provide escape from pipe tunnel and pump rooms to main deck and two (2) shall provide escape from engine room to tween deck (escape trunks). All hatches shall be flush.
Four (4) access hatches shall be provided as indicated on general arrangement plan for accessing the fan rooms. All access hatches shall be flush.
All hatches shall be closed with watertight hatch covers with a central locking device, operated from the inside by a hand wheel. Electronic control shall be installed over the trunk for indication of closure.
Bolts and wing nuts of bronze shall be provided with neoprene gaskets. All moving parts shall be bronze bushed and grease lubricated. Neoprene gaskets on cover shall be fitted after paint application.
The escape hatches shall incorporate hold-back securing devices for covers in open position.
Escape routes shall be arranged in all working compartments where two independent accesses cannot reasonably be fitted.
Four (4) flush hatches shall be installed for lowering spare parts and equipment in the machinery spaces; two (2) in the main deck and two (2) on the tween deck in line with the hatches on main deck. Typical size shall be 2,050 x 1,050 mm, fitted with a watertight bolted steel cover.
Two (2) flush hatches shall be provided of 2,300 x 1,800 mm, one above each pump room. The hatches shall be fitted with a watertight bolted steel cover.
Since the engine room is protected by CO2 fire fighting system all openings on
deck from baseline to engine room shall be gas-tight. 6.3.5 Chain locker
A cylindrical chain locker shall be provided just forward of the collision bulkhead. The diameter of the locker shall be 3,000 mm.
The chain locker shall extend to bottom with a grated floor at 1,500 mm from BL. The bilge well shall be equipped with an ejector serviced by the fire pump.
A cofferdam shall be provided next to the chain locker with access ladder for maintenance. Access manhole shall be closed with watertight manhole centrally bolted cover.
6.3.6 Railings and walkways
Open railing shall be provided alongside walkways and stairs. The height of the top rail shall be according to Classification and authority’s requirements and made of 50 mm OD galvanized steel tube. Two intermediate rails of 20 mm round bar shall be fitted.
Railing stanchions shall be made of flat bar 60 x 19 mm welded to the deck and curtain plate.
A toe plate of 150 mm high shall be provided on floors or walkways.
Where removable railing work is required, the flat bar stanchions shall have 8 mm galvanized chain in between.
Removable railing shall be provided around the main deck. 6.3.7 Ladders and stairs
Steel stairs shall be provided from barge access superstructure to tween deck passageway with access to offices, store, control room, electrical room, battery room and CO2 room and stairs to floor in the machinery room. The stairs shall
have an angle of 55° in machinery spaces and executed with anti-slip steps and 50 mm diameter galvanized steel tube handrail, according China National standard.