Section 4 Process Support Systems

401. General

1. Requirements in this Section apply to systems that do not handle production fluid, but complement the process systems operations, such as fuel systems, compressed air systems, cooling water systems and etc. A typical list of process support systems includes the following:

(1) Purging system

(2) Heating & cooling systems

(3) Fuel oil system

(4) Compressed air system

(5) Inert gas systems

(6) Hydraulic System

2. Plans and data to be submitted

(1) Piping and Instrument Diagrams including piping specification.

(2) Process equipment documentation

(3) Specifications for internal combustion engines and turbines

3. Process support piping design and selection of valves and fittings are to be in accordance with API RP 14E, ASME 31.3 or other recognized standards.

4. Machinery and equipment are to be arranged in accordance with safety requirements in API RP 14J.

402. Design of process support system

1. Control and utility air system

(1) Control and utility air may be supplied by a single air compressor or by a separate compressor for each service. When using a single compressor for both services, controls are to be provided to give priority to control air requirements.

(2) Control air is to be oil-free and dried.

(3) Air compressor suctions are to be at least 3 m from hazardous areas.

2. Control gas system

(1) Gas used for control systems is to be passed through a gas scrubber to remove entrained liquid.

(2) Gas containing hydrogen sulfide is not to be used as instrument gas.

(3) Where gas is used for instrument systems, the area classification in way of these instruments is to be in accordance with API RP 505.

3. Use of produced gas as fuel

Use of produced gas as fuel is to comply with Ch 9, Sec 3, 304. and 305.

4. Purging system for process equipment

(1) Process equipment and systems are to be purged prior to initial startup.

(2) They are also to be purged when being put back into service after shutdown, if there is a pos- sibility of oxygen entering the system during shutdown.

(3) Units not equipped for storage of liquid hydrocarbon may only require temporary inert gas stor-

age containers.

(4) The oxygen content of the inert gas used is not to exceed 5% by volume.

(5) Oxygen monitoring equipment is to be provided to monitor oxygen levels in the inert gas supply.

5. Fuel oil system

(1) Fuel oil pumping arrangements are to be completely separate from other pumping systems, and are not to be connected to other piping systems.

(2) Fuel oil transfer pumps are to be fitted with local and remote controls so they may be stopped

in case of an emergency. Remote controls are to be located in a space not affected by fire at the pump locations.

(3) A containment at least 150 mm high is to be provided at pump areas and arranged to the open drain system.

(4) Oil fuel pipes, which, if damaged, would allow oil to escape from a fuel oil tank having a ca- pacity of 500 Th and above situated above the double bottom, shall be fitted with a cock or valve directly on the tank capable of being closed from a safe position outside the space con- cerned in the event of a fire occurring in the space in which such tanks are situated. Gray cast iron valves are not to be used as shutoff valves for fuel oil tanks.

(5) Non-metallic expansion joints and hoses for use in fuel oil systems are only allowed at machi- nery connections, provided they are in an easily accessible position, and pass the API Spec 16C fire test.

6. Hydraulic system

(1) High flash point hydraulic fluids are to be used, unless a specific system design requires the use of low flash point fluids.

(2) When low flash point fluids are used, precautions are to be taken to minimize fire hazard, by

insulating nearby hot surfaces.

(3) Non-metallic hoses used for oil based hydraulic fluid in all hydraulic control systems must pass API Spec 16C fire test.

7. Lubricating oil system

(1) The lubricating oil piping is to be entirely separated from other piping systems.

(2) Normally opened valves on lubricating oil storage tanks are to comply with the requirements of

5 (4).

(3) Turbines

(A) Turbines are to be provided with a means of automatically shutting off the steam or gas turbine fuel supply upon failure of the lubricating oil system.

(B) Indicators

(a) Indicators are to be fitted to allow monitoring of the pressure and temperature of the water inlet and oil outlet of the oil coolers.

(b) Pressure systems are to be fitted with low-pressure alarm.

(c) Sump and gravity tanks are to be provided with suitable gauges for determining the lev- el of oil within the tank.

(C) Strainers and filters

(a) For auxiliary turbines, a magnetic strainer and fine mesh filter (strainer) are to be pro- vided in the lubricating oil piping to the turbine.

(b) Strainers are to be so arranged as to prevent, in the event of leakage, spraying oil onto heated surfaces.

(4) Internal combustion engines

(A) The lubricating oil pump is to be of sufficient capacity for the maximum output of the engine.

(B) Lubrication oil filter is to be provided and so arranged as to prevent, in case of leakage,

spraying oil onto heated surfaces.

(C) An alarm device with audible and visual signals for failure of the lubricating oil system is to be fitted.

8. Chemical injection system

(1) Non-return valves shall be installed at injection points to production systems.

(2) The design pressure of a chemical injection pump is, as a minimum, to be the same as the system into which it injects.

(3) Flame arrester is to be provided to flammable or combustible tank vent.

9. Heating and cooling systems

(1) The medium used for heating or cooling any hydrocarbon system is to be contained solely within the hazardous area.

(2) The return line of the heating or cooling system is to be provided with means to detect any

hydrocarbon contamination.

10. Water Injection, gas injection and gas lift systems

(1) A non-return valve and an automatic shutdown valve are to be fitted at the injection point to the well.

(2) Water injection systems on units which are intended to operate in areas with ambient design

temperatures below -5°C are to be fitted with winterisation to prevent freezing during periods of shutdown.

(3) If produced water is to be re-injected into the reservoir, areas in which overboard dump lines and drain lines from water injection pump seals are installed are to be considered as hazardous area in accordance with Ch 7.

403.

Process support system equipment

1. Pressure vessels

Pressure vessels are to be designed, constructed, and tested in accordance with the ASME Boiler and Pressure Vessel Code Section VIII Division 1 or Division 2 or other recognized standards.

2. Heat exchangers

(1) Heat exchangers are to comply with applicable sections of ASME Boiler Code Section VIII, Division 1 or Division 2, TEMA Standards or API Std.

(2) Air-cooled heat exchangers are to comply with API Std. 661.

3. Pumps

and Pressure Vessel 660.

Pumps are to comply with requirements in Pt

4. Internal combustion engines and turbines

5 of Rules for the Classification of Steel Ships.

(1) The requirements not specified in this Paragraph are to be in accordance with Pt 5, Ch2 of

Rules for the Classification of Steel Ships.

(2) Gas turbines are to comply with API Std. 616.

(3) Internal combustion engines may not be installed in hazardous area. The installation of Internal combustion engines may be permitted in Zone 1 and Zone 2, provided that the Society is sat- isfied that sufficient precaution has been taken against the risk of dangerous ignition.

(4) Exhaust outlets of internal combustion engines are to be fitted with suitable spark arresting de- vices and to discharge outside the hazardous areas.

(5) Air intakes for internal combustion engines are to be not less than 3 m from the hazardous areas.

(6) Protection of crankcase are to comply with the following:

(A) Ventilation and monitoring

(a) Medium and high speed diesel engines(trunk piston type):

(i) Ventilation is to be provided for the crankcase to prevent accumulation of gas.

(ii) The crankcase vent is to be led to a safe location in the atmosphere through a flame arrester.

(iii) The crankcase is to be provided with oil mist detection arrangements(or engine bearing temperature monitors or equivalent devices) obtained type approval.

(iv) The crankcase is also to be provided with gas detecting or equivalent equipment.

(b) Low speed diesel engines(crosshead type):

(i) The crankcase is to be protected by an oil mist detector or bearing temperature detector.

(ii) Gas detection or equivalent equipment is to be provided for the piston underside

space.

(B) Explosion relief valves

(a) The crankcase is to be provided with relief valves of an approved type, for the purpose of relieving the excess pressure in the event of an internal explosion.

(b) The number and the free area of the relief valves are in accordance with Pt 5, Ch2,

203. 4 of Rules for the Classification of Steel Ships.