CHAPTER 4 Level 3 – Detail Design Approval and Installation
4.1 Description
This is the final Level of the “Gas Fuel Ready” scheme and incorporates both the approval of the detailed drawings and the installation of specified equipment onboard the ship. This Level is also categorized in separate groups, identifying the different parts of the complete design. Level 3 includes the complete list of drawings required for approval of each part before installation, and it can be performed straight after Level 1 or in combination with Level 2. Drawings are to be in compliance with the IGF Code. Upon completion of the installation to the Surveyor's satisfaction, the ship will be eligible for the notation Gas Fuel Ready-III, including descriptive letters for the component or systems that have been installed in accordance with approved plans. After delivery, the survey intervals and their requirements are covered in 4.3 below.
The subgroups of Level 3 are the same as Level 2, above:
System/Component Descriptive Letter(s)
Hull structural reinforcement for LNG storage tank S
LNG fuel storage tank structure TS
LNG fuel storage tank arrangements TA
Fuel gas bunkering system and arrangement BK
Fuel gas supply system GS
Gas vapor handling system BH
Gas Consumers
Main engines ME
Auxiliary engines AE
Gas turbines GT
Main or Auxiliary boilers B
The above descriptive letters are to supplement the notation Gas Fuel Ready-III when the components or systems indicated have been CR approved/surveyed as per the applicable Rules and Guidelines requirements and installed on board to the attending Surveyor’s satisfaction (e.g., Gas Fuel Ready-III (S, GS, ME)). For those instances when only part of a system is installed or when a gas consumer is able to be converted in the future for burning gas, the applicable descriptive letter with appended brief description to indicate the installed equipment will be included. Some examples are indicated below:
GS fuel gas piping
BK manifold
ME convertible to gas
AE convertible to dual fuel
4.2 Plans and Data to be Submitted
Plans and specifications covering the entire installation with all of the accessories are to be submitted and are to include, as applicable. The plans and documents to be submitted for each group of Level 3 are listed below.
4.2.1 Hull Structural Reinforcement for LNG Storage Tank
(a) Detailed drawings of the gas storage tank, supports, collision and anti-floatation arrangements
CHAPTER 4 Level 3 – Detail Design Approval and Installation 4.2 Plans and Data to be Submitted
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(b) Fuel gas storage tank thermal insulation and heat transfer calculation, in association with requirements in 6.4.8 of Part A-1 of the IGF Code for the thermal insulation
(c) Material specifications for tank supports and steel grade selection for inner hull in way of the tank
(d) Specifications of design loads and structural analyses for the gas storage tank supports and hull reinforcement for accommodating the LNG storage tank together with complete stress analysis, as applicable
(e) Weld procedures, stress relieving, and nondestructive testing plans
4.2.2 LNG Fuel Storage Tank Structure
(a) General arrangement of the gas storage tank(s), and as applicable, hold space/gas fuel storage room, including location of the gas detectors, electrical equipment, and lighting
(b) Detailed drawings of the gas storage tank supports and stays, secondary barrier (if required), and insulation
(c) Material specifications for tanks, valves, and associated components
(d) Weld procedures, stress relieving, and nondestructive testing plans.
(e) Specifications of design loads and structural analyses for the gas storage tank(s) together with complete stress analysis as applicable
(f) Sloshing analysis, in association with 6.4.9.4.1.3 in Part A-1 of the IGF Code
(g) Loading limit curve, in association with regulations on loading limit for liquefied gas fuel tanks in 6.8 of Part A-1 of the IGF Code
(h) Tank pressure accumulation calculation, where applicable,in association with the regulations for the maintaining of fuel storage condition, as described in 6.9 of Part A-1 of the IGF Code
4.2.3 LNG Fuel Storage Tank Arrangements
(a) General arrangement of the gas storage tank(s), and as applicable, hold space/gas fuel sto rage room, including location of the gas detectors, electrical equipment, and lighting
(b) Detailed drawings of the gas storage tank supports and stays, secondary barrier (if required), and insulation
(c) Calculation of gas storage tank relief valve capacity including back pressure and relevant supporting documents
(d) Ventilation or inert gas arrangements for the hold space/gas fuel storage room
(e) Fixed gas detection and alarm systems, and associated shutoff and shutdown systems
CHAPTER 4 Level 3 – Detail Design Approval and Installation 4.2 Plans and Data to be Submitted
(f) Gas fuel piping systems including details of piping and associated components, design pressures and temperatures, and insulation, where applicable
(g) Descriptions and schematic diagrams for control and monitoring system including set points for abnormal conditions
(h) Details of all electrical equipment in the hold space/gas fuel storage room
(i) Electric bonding (earthing) arrangement
(j) Operating and maintenance instruction manuals (see 6.8.1, 6.3.12 & 6.7.2.6 in Part A-1 and 18.2.2 to 18.2.4
& 18.4.2.1 in Part C-1 of the IGF Code).
(k) Forced and natural boil-off gas supply system from the tanks to the consumers
(l) Testing procedures during sea/gas trials
4.2.4 Fuel Gas Bunkering System and Arrangement
(a) General arrangement of the gas fuel bunkering system including location of the gas detectors, electrical equipment and lighting
(b) Detailed drawings of the bunkering station, manifolds, valves, couplings and control stations
(c) Gas fuel piping systems including details of piping and associated components, design pressures, temperatures and insulation where applicable
(d) Material specifications for manifolds, valves and associated components
(e) Weld procedures, stress relieving and non-destructive testing plans
(f) Ventilation system
(g) Fixed gas detection and alarm systems, and associated shut-off and shutdown systems
(h) Descriptions and schematic diagrams for control and monitoring system including set points for abnormal conditions
(i) Details of all electrical equipment in the bunkering and control stations
(j) Equipotential bonding and insulating flange arrangement
(k) Emergency shutdown (ESD) arrangements and ESD flow chart
(l) Operating and maintenance instruction manuals
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(m) Testing procedures during sea/gas trials (submitted for survey verification only).
4.2.5 Fuel Gas Supply System
(a) General arrangement of the fuel preparation room including location of the gas detectors, electrical equipment and lighting
(b) Doors and other openings in fuel preparation rooms
(c) Ventilation ducts of fuel preparation rooms
(d) Material specifications for compressors, pumps, evaporators, vaporizers, condensers, coolers, heaters, valves and associated components
(e) Ventilation systems for the fuel preparation room
(f) Fixed gas detection and alarm systems, and associated shut-off and shutdown systems
(g) Gas fuel piping systems including details of piping and associated components, design pressures, temperatures and insulation where applicable
(h) Weld procedures, stress relieving and non-destructive testing plans
(i) Gas compressors
(j) Vaporizers/Heaters
(k) Pressure vessels
(l) Descriptions and schematic diagrams for control and monitoring system including set points for abnormal conditions
(m) Details of all electrical equipment in the fuel gas supply room
(n) Electric bonding (earthing) arrangement
(o) Failure Modes and Effects Analysis (FMEA) to determine possible failures and their effects in the safe operation of the fuel gas supply system
(p) Emergency shutdown arrangements
(q) Operating and maintenance instruction manuals
(r) Forced and natural boil-off gas supply system from the tanks to the consumers
(s) Testing procedures during sea/gas trials (submitted for survey verification only).
CHAPTER 4 Level 3 – Detail Design Approval and Installation 4.2 Plans and Data to be Submitted
4.2.6 Gas Vapor Handling Systems for Reliquefaction Systems
The list of drawings to be submitted depends on the gas vapor handling system that will be selected.
(a) General arrangement of reliquefaction system compartment, as applicable, including location of the gas detectors, electrical equipment and lighting
(b) Ventilation systems for reliquefaction system compartment
(c) Fixed gas detection and alarm systems, and associated shut off and shutdown systems
(d) Gas fuel piping systems including details of pipes and associated components, design pressures and temperatures
(e) Gas compressors
(f) Gas heaters
(g) Gas storage pressure vessels
(h) Descriptions and schematic diagrams for control and monitoring system including set points for abnormal conditions
(i) Details of all electrical equipment in the reliquefaction system compartment
(j) Electric bonding (earthing) arrangement
(k) Failure Modes and Effects Analysis (FMEA) to determine possible failures and their effects in the safe operation of the reliquefaction system
(l) Emergency shutdown arrangements
(m) Operating and maintenance instruction manuals (see Section 18 in Part C-1 of the IGF Code)
(n) Forced boil-off gas supply system from the tanks to the consumers
(o) Testing procedures during sea/gas trials (submitted for survey verification only).
4.2.7 Gas Vapor Handling Systems for Gas Combustion Units
The list of drawings to be submitted depends on the gas vapor handling system that will be selected.
(a) General arrangement of the GCU compartment, including location of the gas detectors, electrical equipmentand lighting
(b) Ventilation system for the GCU compartment
(c) Fixed gas detection and alarm systems, and associated shut-off and shutdown systems
CHAPTER 4 Level 3 – Detail Design Approval and Installation 4.2 Plans and Data to be Submitted
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(h) Gas storage pressure vessels
(i) Descriptions and schematic diagrams for control and monitoring system including set points for abnormal conditions
(j) Details of all electrical equipment in the GCU compartment
(k) Electric bonding (earthing) arrangement
(l) Failure Modes and Effects Analysis (FMEA)
(m) Emergency shutdown arrangements
(n) Operating and maintenance instruction manuals (see Section 18 in Part C-1 of the IGC Code)
(o) Forced boil-off gas supply system from the tanks to the consumers
(p) Testing procedures during sea/gas trials (submitted for survey verification only).
4.2.8 Gas Consumers (Engines, Gas Turbines and Auxiliaries)
The list of drawings to be submitted depends on the propulsion system that will be selected.
(a) General arrangement of engine compartment(s), including location of the gas detectors, electrical equipment and lighting
(b) Ventilation system
(c) Fixed gas detection and alarm systems, and associated shut-off and shutdown systems
(d) Gas fuel piping system including details of pipes and associated components, design pressures and temperatures
(e) Descriptions and schematic diagrams for control and monitoring system including set points for abnormal conditions
(f) Details of the electrical equipment
CHAPTER 4 Level 3 – Detail Design Approval and Installation 4.2 Plans and Data to be Submitted
(g) Electric bonding (earthing) arrangement
(h) Arrangement and details of crankcase protection
(i) Failure Modes and Effects Analysis (FMEA) to determine possible failures and their effects in the safe operation of the engines for each engine type
(j) Arrangement of explosion protection for air inlet manifolds and for exhaust manifolds including design basis and size calculations
(k) Emergency shutdown arrangements
(l) Operating and maintenance instruction manuals
(m) Testing procedures during sea/gas trials (submitted for survey verification only).
(n) Engine specific time referenced by 10.3.1.7 in Part A-1 of the IGF Code, after which if the engine has not started then the fuel gas supply is to be shut off and exhaust system is to be purged
4.2.9 Gas Consumers (Dual Fuel Gas Turbine)
The list of drawings to be submitted depends on the propulsion system that will be selected.
(a) General arrangements showing location of the power plant and individual items of machinery, such as the gas turbine units(s), exhaust gas boilers, turbo generators(s), diesel generators and other associated equipment (such as the gas combustion units(s), reliquefaction plant and the gas supply line to the consumers)
(b) General arrangement of the gas turbine engine enclosure, including location of the gas detectors, electrical equipment, lighting and ventilation, etc.
(c) Gas fuel manifold arrangement and details, including design pressure and temperatures, operational schematics, material specifications and bill of materials
(d) Enclosure, including size and dimensions, gas tightness, entrance and exits and other openings, such as ventilation intakes and outlets
(e) Ventilation systems details, including inlet cooling air calculations for the enclosure
(f) Fixed gas detection and alarm systems, and associated shut off and shutdown systems
(g) Gas fuel piping systems, including details of pipes and associated components, design pressures and temperatures, operational schematics, flange/joints loadings, material specifications and bill of materials
(h) Gas compressors, with details such as type, size, mechanical components, materials used and details of alarms, indication, shutdown and control system.
(i) Mist separators
CHAPTER 4 Level 3 – Detail Design Approval and Installation 4.3 Survey
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(j) Vaporizers
(k) Heat exchangers, including BOG heaters, BOG coolers, etc.
(l) Pressure vessels, including recovery tanks, etc.
(m) Descriptions and schematic diagrams for control and monitoring systems, including set points for abnormal conditions together with control logic for the entire power plant and individual items in the systems.
(n) Details of the electrical equipment in the turbine engine enclosure
(o) Failure Modes and Effects Analysis (FMEA) to determine possible failures and their effects in the safe operation of the dual fuel gas turbine
(p) Electric bonding (earthing) arrangement
(q) Emergency shutdown arrangements
(r) Operating and maintenance instruction manuals
(s) Schematic diagram showing gas and fuel supply lines from the source to the consumers for the entire power plant system
4.3 Survey
4.3.1 Material and equipment inspection
The components or systems indicated in this chapter and intended to install on-board are to be inspected in accordance with CR Guidelines for Survey of Products for Marine Use and the applicable requirements in the Rules for Steel Ships.
4.3.2 Installation Survey
During installation of the specified components or systems for the "Gas Fuel Ready" scheme, the installation survey is to be carried out in the presence of the Surveyor.
4.3.3 Survey after installation
The survey after installation of the specified components or systems for the "Gas Fuel Ready" scheme will be included in Annual Survey and Special Survey in accordance with 1.6.4 and 1.6.5 in Part I of the Rules for Steel Ships, as applicable.