Section 5 Documentation required for design review

5.1.1 Unless otherwise advised, it is the responsibility of the system integrator or packager to agree the scope, functional requirements and boundary interfaces for the gas turbine package with LR and to prepare and submit the information required by this Chapter.

5.1.2 The following should be read in conjunction with Vol 2, Pt 1, Ch 3, 3 Documentation required for design review.

5.1.3 During the life of the gas turbine, details of any proposed changes that affect the safe and reliable operation of the gas turbine are to be submitted to LR for approval.

5.1.4 Where considered necessary by LR, additional documentation may be required.

5.2.1 A System Operational Concept document covering the propulsion system, see Vol 2, Pt 1, Ch 3, 3.4 System operational concept.

5.2.2 A System Design Description, see Vol 2, Pt 1, Ch 3, 3.5 System design description, for the gas turbine package, including references to the System Operational Concept document required by Vol 2, Pt 2, Ch 2, 5.2 Documentation 5.2.1 and to Plans required by Vol 2, Pt 2, Ch 2, 5.2 Documentation 5.2.4, is to be submitted so that the function of all Mobility, Ship Type and safety critical components and systems necessary for the turbine operation is clearly defined. This is to include a general overview of the operating principles supported by schematics explaining the functionality of individual systems and sub-systems. The information is to relate to the gas turbine capability and functionality under defined normal and reasonably foreseeable abnormal operating and fault conditions such as recovery from a failure, degraded modes of operation, or malfunction, with particular reference to the functioning of the control, monitoring, alert and safety systems and any subsystems.

5.2.3 Where a gas turbine unit may be required to operate for continuous periods outside its recommended continuous operating design envelope, details of the intended operating conditions, time intervals and frequency of use together with documentary evidence indicating the suitability of the design and any limitations under these conditions are to be included in the System Design Description required by Vol 2, Pt 2, Ch 2, 5.2 Documentation 5.2.2. Arrangements may include time alongside, manoeuvring, close-down and other military operations or trials.

5.2.4 To assess compliance with the design requirements of the Rules and for inspection, installation and record purposes, the following are to be submitted for consideration:

1. Plans:

   • Casing construction arrangement;
   • Arrangements of combustion chambers, intercoolers and heat exchangers;
   • Gas generator rotating components;
   • Control engineering systems, see Vol 2, Pt 9, Ch 7 Control, Alerts and Safety Systems;
   • Inlet and exhaust ducting arrangement;
   • Nozzles, blades and blade attachments;
   • Power turbine components;
   • Rotors, bearings and couplings;
   • Section assembly;
   • Securing arrangement, where applicable, including details of resilient mounts, see also Vol 2, Pt 1, Ch 3, 3.3 Calculations and specifications 3.3.5;
   • Details of bleed air, anti-stall and surge systems or devices;
   • Details of materials of all load bearing and torque transmitting components and pressure retaining parts;
   • Details of materials for rotors and discs are to be submitted for approval;

2. Schematics:

   • Cooling and sealing air arrangements for compressor and gas generator components;
   • Cooling water system;
   • Fuel system;
   • Gas turbine unit acoustic enclosure, if applicable, including fire, insulation, ventilation and drainage systems;
   • Lubricating oil systems;
   • Starting system;
   • Machinery (safety) interlocks;

   and, where applicable:

   • Fire systems (Piping and Instrumentation diagram);
   • Enclosure and base frame;
   • Alternator;
   • Highspeed coupling shaft.

5.2.5 Miscellaneous. Details of the following are also to be submitted:

1. Operating manuals that describe the particulars of each system, including reference to the functioning of subsystems and with particular reference to any predicted adverse affects, e.g. fouling;

2. Maintenance manuals that include declared lives of critical components and overhaul schedules recommended by the manufacturer;

3. Fuel specifications and

4. The maintenance and support arrangements by which the gas turbine unit is to be exchanged (where applicable).

5.2.6 Details of proposed welding procedures and proposals for the routine examination of safety-critical and/or structurally significant joints by non-destructive means are to be submitted for consideration.

5.2.7 The manufacturer’s proposals for testing the gas turbine are to be submitted for consideration and are to be agreed by the Owner. These are to include details of rotor balancing techniques, methods of determining the integrity of pressure casings and heat exchanger tests.

5.2.8 An engineering safety and justification report for the gas turbine unit defined in Vol 2, Pt 2, Ch 2, 1.1 Definitions 1.1.2, stating design standards, assumptions and providing technical evidence. This is to be derived from a Risk Based Analysis in accordance with Vol 2, Pt 2, Ch 2, 5.2 Documentation 5.2.9 and is to include, but is not to be limited to:

1. Possible failure modes of internal components, to include such items as rotors, discs, seals, bearings and coupling, etc. and measures adopted to mitigate such failures that may have an effect on the internal machinery or the surrounding environment/structures/systems, taking due account of suitability of materials and the effects of stress raisers, etc.;

2. Limiting operating parameters;

3. Details of life-limited critical components, including their declared lives and residual lives or balance of planned life remaining, in terms of operating time or operating cycles, or where life is derived from declared acceptance criteria, and the associated maintenance strategies;

4. Short-term high power operation;

5. Details of mounting and securing arrangements;

6. Rotor and blade vibratory characteristics;

7. Details of potential failures that could lead to hazardous or major consequences and/or degradation in systems performance that could lead to failures and which are to be notified to the Operators;

8. Common failure modes and system redundancy fitted to minimise potential single points of failure.

5.2.9 A Risk Assessment is to be carried out in accordance with the requirements ofVol 2, Pt 1, Ch 3, 18 Risk Assessment (RA) and is to include the following associated sub-systems:

1. Starting and stopping;

2. Fuel;

3. Lubricating oil;

4. Hydraulic oil;

5. Cooling arrangements;

6. Intercooler, where applicable;

7. Air induction;

8. Exhaust;

9. Recuperator, where applicable;

10. Gas turbine mounting;

11. Electrical power supplies;

12. Control systems;

13. Safety systems;

14. Ventilation;

15. Fire protection (where applicable);

16. Emissions abatement plant;

17. Wet washing arrangements;

18. Rotor turning arrangements.

It is not necessary to consider failure modes relating to the gas turbine components for the purposes of this Section.

5.2.10 For the gas turbine package components and system support services defined inVol 2, Pt 2, Ch 2, 1.1 Definitions 1.1.2.(b), Vol 2, Pt 2, Ch 2, 1.1 Definitions 1.1.2.(c) and Vol 2, Pt 2, Ch 2, 1.1 Definitions 1.1.5, the engineering safety and justification report defined in Vol 2, Pt 2, Ch 2, 5.2 Documentation 5.2.8 is to include details of potential failures that could lead to hazardous or major consequences and/or degradation in systems’ performance that could lead to failures and which are to be notified to the Operators.

5.2.11 Where applicable, the engineering safety and justification report defined in Vol 2, Pt 2, Ch 2, 5.2 Documentation 5.2.8 is to include the fire protection arrangements specific to the package, including arrangements for the gas turbine enclosure (if provided), see Vol 2, Pt 1, Ch 3, 3.3 Calculations and specifications 3.3.15 and Vol 2, Pt 1, Ch 3, 5.15 Fire detection, alarm and extinguishing arrangements.

5.2.12 Where the gas turbine is a prime mover in an electrical power generation system, the engineering safety and justification report defined in Vol 2, Pt 2, Ch 2, 5.2 Documentation 5.2.8 is to include an assessment of the systems defined in Vol 2, Pt 2, Ch 2, 1.1 Definitions 1.1.2.(d), addressing requirements in Vol 2, Pt 9 Electrotechnical Systems.

5.2.13 In addition to the applicable plans and particulars required by Vol 2, Pt 9, Ch 7 Control, Alerts and Safety Systems, the following information for control, monitoring, alert and safety systems relating to the operation of an electronically controlled unit is to be submitted:

1. Gas turbine package configuration details, see Vol 2, Pt 2, Ch 2, 10.11 Control engineering systems 10.11.1;

2. Software quality plans, including configuration management documents;

3. Software safety evidence;

4. Software assessment inspection report such as SCA or IEC 61508, as applicable, which is to include the following as a minimum:

   • Identify the standards used for analysis and system design;
   • Identify the engine, its purpose and the associated objectives of the analysis;
   • Identify any assumptions made in the analysis;
   • Identify the equipment, system or sub-system, mode of operation and the equipment;
   • Identify potential failure modes and their causes;
   • Evaluate the local effects (e.g. fuel injection failure) and the effects on the system as a whole (e.g. loss of propulsion power) of each failure mode;
   • Identify measures for reducing the risks associated with each failure mode (e.g. system design, failure detection and alarms, redundancy, quality control procedures for sourcing, manufacture and testing, etc.);
   • Identify trials and testing necessary to prove conclusions.

5.3.1 The following calculations and specifications are to be submitted. Where appropriate, this information can be included in the System Design Description required by Vol 2, Pt 2, Ch 2, 5.2 Documentation 5.2.2:

1. Vibration analysis and alignment analysis as required by this Chapter;

2. The material specifications, including the minimum specified tensile strength of each shaft and coupling component, are to be stated;

3. Details of the gas turbine manufacturer’s requirements for air inlet filtration, including maximum allowable inlet pressure drop, and of the maximum allowable exhaust depression. Air intake and uptake arrangements, with calculations demonstrating that the intake and uptake designs satisfy those requirements, are to be submitted for consideration;

4. Where a gas turbine package includes components having a specified life in terms of operating time or operating cycles, or where life is derived from declared acceptance criteria, details are to be submitted for consideration. Details of proposed arrangements for monitoring life progression are to be submitted for consideration;

5. Statement indicating the suitability of flexible hoses;

6. Flexible hose and bellows expansion piece registers selected for use in the package, see Vol 2, Pt 1, Ch 3, 4.19 Flexible hose and bellows expansion piece registers;

7. Machinery fastening:

   • Documentary evidence and calculations indicating that machinery is mounted securely for the ship’s motions and accelerations, including shock, to be expected during service;
   • Calculations to demonstrate that mountings can withstand the design shock acceleration without fracturing;
   • Plans showing the arrangement of resiliently mounted machinery are to indicate the number, position, type and design of mounts;
   • Natural frequency calculation of resiliently mounted machinery;
   • Mass and centre of gravity for the gas turbine and related equipment.

5.3.2 Vibration and alignment calculations and specifications are to be submitted as part of the propulsion system requirements. See Vol 2, Pt 3, Ch 2 Shafting Systems.