Section 8 Piping

8.1.1 Fuel oil and hydraulic oil piping systems arrangements are to comply with ChaptersPt 5, Ch 10 Piping Design Requirements and Pt 5, Ch 12 Machinery Piping Systems as applicable.

8.1.2 Fuel oil pipe systems in general, tanks and their fittings are to comply with the requirements of Pt 5, Ch 12 Machinery Piping Systems and Pt 3 Ship Structures (General).

8.1.3 Each fuel oil pump and hydraulic oil pump essential for engine operation is to be capable of supplying the quantity of oil for engine operation at its maximum continuous rating.

8.1.4 All external high pressure fuel delivery lines between the high pressure fuel pumps and fuel injectors are to be protected with a jacketed piping system capable of containing fuel from a high pressure line failure. If flexible hoses are used for shielding purposes, these arrangements are to be approved.

8.1.5 The hydraulic oil pressure piping between the high pressure hydraulic pumps and hydraulic actuators is to be protected with a jacketed piping system capable of containing hydraulic oil leakage from a high pressure pipe failure.

8.1.6 Where flammable oils are used in high-pressure systems, the oil pipe lines between the high pressure oil pump and actuating oil pistons are to be protected with a jacketed piping system capable of preventing oil spray from a highpressure line failure.

8.1.7 Accumulators and associated high pressure piping are to be designed, manufactured and tested in accordance with a standard applicable to the maximum pressure and temperature rating of the system.

8.1.8 Engine fuel system components are to be designed to accommodate the maximum peak pressures experienced in service. In particular, this applies to the fuel injection pump supply and spill line piping which may be subject to high-pressure pulses from the pump. Connections on such piping systems should be chosen to minimise the risk of pressurised fuel oil leaks.

8.1.9 The protection is to prevent fuel oil or fuel oil mist from reaching a source of ignition on the engine or its surroundings. Suitable drainage arrangements are to be made for draining any fuel oil leakage to a collector tank(s) fitted in a safe position. An alarm is to be provided to indicate that leakage is taking place.

8.1.10 All valves, cocks and screwed connections are to be of a type tested type applicable to the maximum service conditions anticipated in normal service.

8.1.11 Isolating valves and cocks are to be located as near as practicable to the equipment to be isolated. All valves forming part of the fuel oil and hydraulic oil installation are to be capable of being controlled from readily accessible positions above the working platform.

8.1.12 High pressure fuel oil and high pressure hydraulic oil piping systems are to be provided with high pressure alarms with set points that do not exceed the system design pressures.

8.1.13 High pressure fuel oil and high pressure hydraulic piping systems are to be provided with suitable relief valves on any part of the system that can be isolated and in which pressure can be generated. The settings of the relief valves are not to exceed the design pressures. The valves are to be of adequate size and so arranged as to avoid an undue rise in pressure above the design pressures.

8.1.14 Equipment fitted for monitoring pressures and temperatures in the high pressure fuel oil and high pressure hydraulic oil systems is to comply with a Recognised Standard suitable to the anticipated vibration and temperature conditions.

8.1.15 A fatigue analysis is to be carried out in accordance with a standard applicable to the system under consideration and all anticipated pressure, pulsation and vibration loads are to be addressed. The analysis is to demonstrate that the design and arrangements are such that the likelihood of failure is as low as reasonably practicable. The analysis is to identify all assumptions made and standards to be applied during manufacture and testing of the system. Any potential weak points which may develop due to incorrect construction or assembly are also to be identified.

8.1.16 For high pressure oil containing and mechanical power transmission systems, the quality plan for sourcing, design, installation and testing of components is to address the following issues:

1. Design and manufacturing standard(s) applied.

2. Materials used for construction of key components and their sources.

3. Details of the quality control system applied during manufacture and testing.

4. Details of type approval, type testing or approved type status assigned to the machinery or equipment.

5. Details of installation and testing recommendations for the machinery or equipment.

8.2.1 Where the surface temperature of the exhaust pipes and silencer may exceed 220ºC, they are to be water cooled or efficiently lagged to minimize the risk of fire and to prevent damage by heat. Where lagging covering the exhaust piping system including flanges is oil-absorbing or may permit penetration of oil, the lagging is to be encased in sheet metal or equivalent. In locations where the Surveyor is satisfied that oil impingement could not occur, the lagging need not be encased.

8.2.2 Where the exhaust is led overboard near the waterline, means are to be provided to prevent water from being siphoned back to the engine. Where the exhaust is cooled by water spray, the exhaust pipes are to be self-draining overboard.

8.2.3 Where the exhausts of two or more engines are led to a common silencer or exhaust gas-heated boiler or economizer, an isolating device is to be provided in each exhaust pipe.

8.2.4 Exhaust gases are to be led overboard and should be blown out in a direction away from the ship.

8.3.1 In designing the compressed air installation, care is to be taken that the compressor air inlets will be located in an atmosphere reasonably free from oil vapour or, alternatively, an air duct from outside the machinery space is to be led to the compressors.

8.3.2 The air discharge pipe from the compressors is to be led direct to the starting air receivers. Provision is to be made for intercepting and draining oil and water in the air discharge for which purpose a separator or filter is to be fitted in the discharge pipe between compressors and receivers.

8.3.3 The starting air pipe system from receivers to main and auxiliary engines is to be entirely separate from the compressor discharge pipe system. Stop valves on the receivers are to permit slow opening to avoid sudden pressure rises in the piping system. Valve chests and fittings in the piping system are to be of ductile material.

8.3.4 Drain valves for removing accumulations of oil and water are to be fitted on compressors, separators, filters and receivers. In the case of any low-level pipelines, drain valves are to be fitted to suitably located drain pots or separators.

8.3.5 The starting air piping system is to be protected against the effects of explosions by providing an isolating non-return valve or equivalent at the starting air supply to each engine.

8.3.6 In direct reversing engines, bursting discs or flame arresters are to be fitted at the starting valves on each cylinder; in non-reversing and auxiliary engines, at least one such device is to be fitted at the supply inlet to the starting air manifold on each engine. The fitting of bursting discs or flame arresters may be waived in engines where the cylinder bore does not exceed 230 mm.

8.3.7 Alternative safety arrangements may be submitted for consideration.

8.4.1 The pumping arrangements, including cooling water and lubricating oil systems, are to comply with the requirements of Pt 5, Ch 12 Machinery Piping Systems.