DNV GL Gas ready notation - Intertanko LNG WG Feb 2013/DNVGL... · 2015-02-19 · Framework for contract negotiations between owner and yard. ... MEc Main engine(s) ... with MEi)

DNV GL © 2013 12th February 2015 SAFER, SMARTER, GREENERDNV GL © 2013

12th February 2015Olav Tveit

MARITIME

DNV GL Gas ready notation

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ISTEC WG on Alternative Fuels

DNV GL © 2013 12th February 20152


Purpose of a GAS READY notation

Preparation of a newbuilding for potential later conversion to LNG fuel operation.

Framework for contract negotiations between owner and yard.

Clear guidance on relevant scope for all involved parties in the NB project

(Yard, owner, designer, approval engineers, surveyors).

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Application of GAS READY notation

The GAS READY class notation provide compliance with rules in force at the time of Contract for Construction for the new-building.

The rules and international regulations in force at the time of a later ship conversion to LNG fuel will be applicable, regardless of the notation:

– At time of conversion, documentation shall be submitted for approval. The design verification from the new building stage will be used to support the approval.

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GAS READY (X1, X2, X3, …) where qualifier XN is:

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XN Content CommentGAS READY

D The design for the ship with LNG as fuel is found to be in compliance with the GAS FUELLED notation rules applicable for the new‐building, ref. Pt.1 Ch.1 Sec.2 A300.

Mandatory

S Structural reinforcements to support the fuel containment system (LNG fuel tank(s)) are installed, and materials to support the relevant temperatures are used

T Fuel containment system (LNG fuel tank(s)) is installed

P The ship is prepared for future gas fuel system installations: Pipe routing, structural arrangements for bunkering station, gas valve unit space, fuel preparation space if relevant (optional)

MEc Main engine(s) installed can be converted to dual fuel Mandatory (can be replaced with MEi)

MEi Main engine(s) installed can be operated on gas fuelAEc Auxiliary engines installed can be converted to dual fuel The auxiliary engine capacity

after conversion shall be sufficient for the ship power balance.

AEi Auxiliary engines installed can be operated on gas fuel

B Boilers installed are capable of burning gas fuel

Misc Additional systems and equipment are installed on board from new building stage.

Based on agreement between owner and yard, and detailed list provided to Society for acceptance.


Examples of relevant use of notation

GAS READY (D, MEc)

– the future LNG fuelled design is examined and found to be in compliance with rules in force at time of new building

– Main engine(s) are of a type that can be converted to dual fuel engines

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Example: GAS READY (D, MEc, P)

– Pipe ducting for bunkering pipe (if going through ship) is installed, space for other gas ducting is provided, structural spaces for bunkering station, Gas Valve Unit and Fuel Preparation Space is provided on board.

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Example: GAS READY (D, MEc, P, S)

– The ship is constructed with the necessary structural reinforcement and low temperature materials for the future LNG fuel tank (s).

– If the details of the LNG tank system is not known at NB stage, a relevant weight can be included in calculations for global strength, and a relevant temperature to be assumed. Details of the local supports can be prepared later. The chosen weights/ temperature will then pose limitations to the later conversion.

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Example: GAS READY (D, MEc, AEc, B)

– Main engines are of a type that can be converted to dual fuel engines

– Auxiliary engines are of a type that can be converted to dual fuel engines

– Boilers are capable of burning gas fuel.

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Design verification of future LNG fuelled ship (qualifier D)

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Documentation Additional description Info Gas Ready General arrangement drawing Including LNG tank location with distance from ship side, adjacent spaces,

bunkering station location, pipe routing, engine room arrangement and location of any other spaces containing gas equipment. Location of entrances (air locks as relevant) for spaces with gas equipment shall also be shown.

EX

Gas Ready Engine room arrangement Only if not included in General Arrangement EXGas Ready Design philosophy/ description Including information on the machinery configuration, engine room arrangements,

fuel arrangements, shut down philosophy, redundancy considerations etc.EX

Gas Ready Hazardous zones drawing EXGas Ready Ventilation system For gas equipment spaces including ventilation capacity, location of inlets and

outlets, segregation from other ventilation systemsEX

Gas Ready Tank arrangement drawing Including arrangement of tank connection space and pump rooms/compressor rooms if relevant.

EX

Gas Ready Calculations for structural strength for the tank location

If details of the LNG tank system are unknown, estimates should be made (refer to Sec.2 1.1.1 for guidance)

EX

Gas Ready Temperature calculations around LNG fuel tanks

If details of the LNG tank system are unknown, estimates should be made (refer to Sec.2 1.1.1 for guidance)

EX

Gas Ready P&ID for LNG bunkering and gas fuel systems

Including details for double piping/ducts and arrangement/location of vent mast/vent outlet(s) for pressure relief valves and purging

EX

Gas Ready Inert gas system EXGas Ready Structural/passive fire protection in relation to LNG tank/other spaces with gas equipment

EX

Gas Ready Bilge system (If fitted in spaces containing gas equipment) EXGas Ready Fire extinguishing in relation to the gas installations

EX

Gas Ready Stability calculations with LNG tank(s) included

EX

Gas Ready Bunkering station arrangement Including drip trays and water curtain arrangement if bunkering rate is going to be high

EX


Survey scope- for NB phase only

The GAS READY class notation does not include survey requirements for follow up of the ship when in operation.

– At time of conversion a survey and evaluation of the condition of the equipment or systems installed from new building stage will be done.

– The test scope will depend on time elapsed from new building, and in what way the systems and components have been preserved/ maintained.

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DNV GL Gas ready notation - Intertanko LNG WG Feb 2013/DNVGL... · 2015-02-19 · Framework for contract negotiations between owner and yard. ... MEc Main engine(s) ... with MEi)

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