ANNEXURE G, PRESERVATION OF IDLE EQUIPMENT / MATERIALS.

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1 ANNEXURE G, PRESERVATION OF IDLE EQUIPMENT / MATERIALS. Preservation of idle equipment installed in the plant involves safeguarding unattended and inactive equipment from deterioration during their down period, generally above one month arising out due to the reasons like feed problems, haulage problem, major repairs, revamps, modifications, retrofitting, etc. Deterioration of equipment during periods of idling is usually caused by conditions entirely different from those that exist during operation. Many deposits formed during operations turn usually corrosive under shutdown conditions. Moisture, oxygen, dirt, dust, ultraviolet rays, extreme pressure and temperature, corrosive environment of coastal areas and closeness to other chemical plants, are the some of the factors causing deterioration. Preservation of static and rotary equipment and their spare parts, which are required to be kept in store for prolonged periods, needs to be carried out to prevent their deterioration, and as such preservation procedures for the equipment/spares kept in store should be adopted. New equipment received at plant/project site should be preserved considering manufacturer s recommendations. PRESERVATION METHODS: If it is expected that site storage will be required for a period longer than the time the packaging will protect the equipment, additional preservation measures will be taken and following techniques followed. External Protection: The paint specification will be followed. However, attention shall be paid that intermediate paint coats are applied soonest. Blank metal parts will be protected by e.g. rustban products of ESSO or SHELL Ensis Internal Protection: Systems containing hydrocarbon will be sprayed, flushed or filled with suitable oil. Nitrogen blankets will be applied and maintained on stainless equipment. Apply nitrogen blankets preferably after all internal work is finished in order to avoid extensive purging operations. Nitrogen in a vessel can be dangerous. Apply all necessary warning plates near all vessel entrances. All construction personnel shall be familiarized with the risks of nitrogen blankets. This instruction is the personal responsibility of the safety engineer. SCOPE:- This standard lays down the preservation procedures to be followed in oil and gas installations for various static mechanical equipment installed at plant and for the equipment / spares kept in stores. The scope does not include the electrical equipment, instruments and chemicals. DEFINITIONS a) Preservation: Preservation is safeguarding of unattended and inactive equipment from deterioration during their down period. b) Coating: Coating means an application of a coat of preservative media like paint, Oil or grease etc., c) Surface Preparation: Surface Preparation includes cleaning of the parent metal surface for removing foreign particles like rust, scale, liquid etc., by mechanical or chemical cleaning techniques. CONSIDERATION FOR SELECTION OF PROTECTIVE SYSTEM:- A careful study should be undertaken before finalising a protection system. This should consider the type of equipment, its cost and ease of repair/replacement, period of protection,

2 rate of deterioration expected and allowable deterioration etc. Equipment, which can be shifted easily, should preferably be moved to warehouse. Before going for protective measures, following should be considered: a) Period of shutdown b) Allowable deterioration and rate of deterioration c) Probability of reuse d) Expenditure for repair/replacement e) Time for repair / replacement after the shutdown f) Type of protection systems (various alternatives) g) Condition of the equipment h) Criticality of the service i) Type of environment in which equipment/spares are to be stored. Equipment/spares will need no preservation if a) It has become obsolete and will not be put to service again. b) It has deteriorated beyond economical repair and required to be condemned. c) The estimated value of the equipment is not worth the expenditure to be made for preservation, if it is not in critical service. PRESERVATION OF IDLE STATIC EQUIPMENT This section covers the Preservation of following idle equipment. a) Launcher and Receiver. b) Pipelines. PRESERVATION OF LAUNCHER AND RECEIVER Launcher and Receiver need to be carefully protected when idle. It may deteriorate due to conditions, which are different from those that exist during operation. The deterioration may be primarily due to water, sludge or other corrosive elements in the entrapped process fluids and environmental conditions. Some fluids may have a tendency to congeal after a long time of retention. Preservation technique should be based on the duration of idleness, type of equipment, its service and environment. Exchangers in non corrosive service should be preserved in case idle period is more than six months. For Launcher and Receiver in corrosive services, preservation should be done based on corrosiveness of the fluid. The following procedures for preservation should be adopted: b) Clean all the parts thoroughly by hydro blasting / hydro jetting or chemical cleaning. No deposits should be left on inside or outside surface of the equipment. c) Thoroughly coat with preservative oil/grease on the required surfaces including bolting flange and gasket faces, etc. d) Reassemble all components, blank off all nozzles and close all vents and drains. e) All the exposed bolts and flanges to be coated with grease. f) Austenitic stainless steel component should be suitably passivated before exposure to atmosphere in line with the procedure as laid down in NACE Standard RP g) Depending on the environmental conditions, coating to be applied on the external surfaces. If the weather is very humid, completely remove the insulation and apply the paint. h) For finned air cooler, clean the tubes internally, circulate preservative oil through the tubes and seal off all the header boxes. PRESERVATION OF PIPELINES The following procedures should be adopted a) Flush the lines clean b) Open the flange joints and valves at low points to ensure complete draining. c) Dry the lines or circulate inhibited or uninhibited oil through them d) Inspect insulated and wrapped lines, uncovering the piping where leaks are suspected. e) Repair all damaged insulation and wrapping. Bare pipe should be wire brushed and painted. f) Lubricate all valves.

3 g) Spray all external surfaces of the valves with oil and cover valve stem with grease. Relief valve should be rotated or separated from their discharge piping. Their discharge side should be sprayed with oil and covered with water proof paper or plastic. h) Tighten all flanges. Spray mating flanges joints with oil, and wrap them with suitable wrapper to prevent crevice corrosion between mating flanges. PRESERVATION OF MATERIALS IN STORES Moisture, oxygen and atmospheric conditions are the main contributing factors causing deterioration. These may cause rusting, pitting of surfaces and other forms of deterioration. Proper identification system should be used for material stored in the warehouse to avoid mixing. Procedure for preservation of stored material should be adopted as follows. RETURN BENDS: CS / Low alloy steel cast plug type return bends should be stored in a covered shed. Grease preservative shall be applied on all the machined and threaded surfaces. However other type of return bend can be stored outdoors after applying necessary protective coatings as given to heater tubes in downward position to avoid any accumulation of water inside the bend. PRESERVATION OF PIPES, PIPE FITTINGS AND VALVES PRESERVATION of PIPES: Both CS and low alloy steel pipes can be stored outdoor in a self draining position on a concrete surface either on steel racks or woody rafter placed in such a position that rain water does not accumulate and affect pipes. Pipes shall not be allowed to get submerged in ground or pool of water. Pipes/ pipe fittings shall be protected with an external coat of black bituminous paint. Pipes shall also be painted internally at the ends, upto a length of 12" or as practicable. Stainless steel pipes shall be stored indoor on wooden rafters/ concrete, separate from CS, with ends opened or plugged. The ink used for marking, if any shall be free from chloride, sulphur and lead. For pipes with threaded connection, extra care shall be taken in protecting the threads by putting plastic caps or wrapping with jute cloth. PRESERVATION of FLANGES: Flanges with anticorrosive painting shall be stacked on stands / concrete or wooden sleepers with their gasket seating surfaces at the bottom and covered with tarpaulin. All the flange gasket seating surface must have a protective coating & extreme care must be taken during handling to avoid damage. All SS flanges should be stored indoors. PRESERVATION of PIPES FITTINGS: Forged fittings can be stored outdoor on sloped concrete surface or wooden platform. All fittings shall be preferably given a coat of anticorrosive paint and shall be stored in such a location that rain water does not accumulate in it. Stainless steel fittings should be stored indoors. PRESERVATION of FASTENERS: Fasteners shall be kept indoors. Carbon steel and alloy steel fasteners shall be stored in separate bays after oil preservation spray. Stainless steel fasteners do not require any protection. PRESERVATION of VALVES: End cover of all the valves shall be plugged by Wooden / Rubber / PVC blanks. Valves shall be stacked on a concrete surface on wooden rafters, with wooden planks on flanges. Grease shall be applied on valve steel spindle and flange faces of CS & AS valves. Valves shall be kept in upright with spindle upward and gate in closed position. All SS valves shall be stored indoor without any preservative.

4 PRESERVATION OF STRUCTURAL STEEL: Structural steel shall be positioned in a way to allow self draining. Structural steel should not be in contact with soil during preservation. PRESERVATION OF LAUNCHER & RECEIVER SHELL: Closed vessel shall be kept on their steel supports. In absence of steel support, wooden saddles shall be used. Vessel shall be painted externally with Zinc Oxide primer. Preservative oil spray shall be done on internal surface. Flanged faces shall be greased and covered with wooden boards. All the nozzles shall be suitably covered so that rain water will not ingress. ELECTRICAL EQUIPMENTS AND MOTORS: GENERAL: Where vendors provide recommendations for site storage and protection, these are to be followed and take precedence over the following recommendations. Where prolonged site storage is involved, which is not under the control of vendors, equipment guarantees are invalidated. However most vendors offer a re-furbishing service after which equipment guarantees are re-instated. Such a service is outside normal Company contracts but clients are recommended to take up this option where applicable at their own expense. Storage: Electrical equipment must be stored in the warehouse. 220 and 110 volt electrical supply to be available adjacent to stored motors and equipment to enable anti-condensation heaters and equipment to be energized where necessary. Equipment transportation supports and temporary stiffening to be checked for soundness and repaired as necessary. Ensure all nameplates are intact and secure. All motors to have shafts manually rotated frequently, at least once per week. This must not be carried out with tools which will damage or mark motor shafts. Protection: All damaged painted Mark/Tag Numbers to be reinstated and maintained. All threaded entries to be plugged and threads recoated with rust preventatives where necessary. All gland plates to be checked and reinstated where required. Where moisture absorbents are included to protect equipment it should be replaced with a fresh charge immediately on receipt in the site stores and replaced on a regular basis thereafter. Motors: Motor bearings to be checked regularly to ensure grease is in good condition, should it harden or be discoloured the bearings should be cleaned out and regressed. Motor condensate drain plugs to be removed periodically to remove any accumulated moisture. Plugs to be replaced to avoid ingress of dust. All bright metal parts, machined surfaces (i.e. shafts) to be coated with rust preventatives. All 6000V. Motors should have insulation resistance values measured and recorded every 3 months against climatic conditions at time of test. If the reading is not greater than 6 mega

5 ohm an approved method of drying out is to be undertaken to achieve acceptable resistance readings. Connect anti-condensation heaters. Transformers and Capacitors: Where units are supplied complete with insulation liquids/gases these should be checked on arrival at Site. If level or pressure is not within vendor's tolerances, possible leaks should be located and rectified. Monthly checks on level/pressure should be made and rectification work carried out as necessary. Any separately supplied insulation liquids should be stored on an incline, containers should not be left stored in upright position. Switchgear, Motor Control Centres, Inverters, Battery Charger Units, Etc.: Unless provided with anti-condensation heaters the equipment shall be removed from the packing cases with the plastic coverings left in place and resealed where damage has occurred during shipment. Where anti-condensation heaters are fitted these shall be connected. Spot insulation tests shall be carried out every 6 weeks and where readings are low an approved drying out procedure shall be adopted to achieve acceptable resistance readings. Batteries should be stored in an inactive area to avoid accidental breakage and seals should be regularly checked for damage. Damaged seals shall be renewed in accordance with Vendors instructions. Nickel-cadmium and lead-acid batteries that have been shipped dry do not require maintenance. Electrolyte levels in batteries that have been shipped wet should be checked and topped up as required. These batteries should also be given a re-freshing charge tri-monthly. Cable: Measure and record gas pressure in low pressure gas filled cable when received and weekly thereafter. If falling pressure indicates a leak in cable, maintain same with dry nitrogen until leak is sealed. Rotate reels of paper insulated lead sheathed cable 90 every 2 weeks to prevent migrating oil from collecting at low points. INSTRUMENTATION: General: Where vendors provide recommendations for site storage and protection these are to be followed and take precedence over the following recommendations. Where prolonged site storage is involved, which is not under the control of vendors, equipment guarantees are invalidated. However most vendors offer a re-furbishing service after which equipment guarantees are re-instated. Such a service is outside normal Company contracts but clients are recommended to take up this option where applicable at their own expense.

6 Storage: A warm, clean, dry and vibration free environment in a secure under cover storage area is required. Recommended environment conditions are temperature range of 15 C to 30 C and a humidity of between 30 to 40%. Instruments can be stored in the above environment for up to 4 months in their shipment cases. However, where cases/packing have been opened the plastic coverings are to be retained and resealed in the manner they were shipped. Where moisture absorbents are included they are to be replacing with the new charge on receipt on site and further replaced at regular intervals thereafter. Adjacent 220 and 110 volt supply made available for energizing equipment as necessary. Panels to be stored up-right and level, any temporary transportation/strengthening supports to be reinstated and maintained. Threaded connections to be re-capped and rust protected, also maintained. Ensure all Nameplates/Tags/Gland plates are intact and secure, also maintain. Protection: Local Instruments: All openings shall be tightly plugged against entry of water. Panel Instruments: The power pack units of the control panel racks shall be energized at monthly intervals. For storage in original packing refer to recommendation of vendor. Delicate Instruments: 1. Panel instruments 2. Distribution control components 3. Racks with power supply and/or cards 4. Computer racks and components 5. Programmable controllers will be stored in air conditioned spaces. Instruments with Electronic Components: 1. Transmitters 2. I/P converters, and others Will be stored shielded from direct sun radiation. Safety Relief Valves and Control Valves: Refer to vendor's recommendations. Safety valves shall be stored in the warehouse and either dummy installed in the line or the lines blanked off. The valves shall be stored indoors in a clean, dry environment. Avoid extreme temperatures and humidity conditions. Threaded connections to the capped and rust protected. Ensure all Nameplates/Tags/Gland plates are intact and secure, also maintain. For stainless steel safety valves special instructions should be followed.

7 Stainless steel (alloys containing more than 10% chromium) equipment, components, and materials shall be protected as follows: 1. Indoor storage, 2. Not in contact with the soil or with porous supports such as raw wood. Protective coatings are acceptable alternatives to covered storage. In addition, austenitic stainless steels shall not be exposed to salt water or salt spray.