CHEMICAL TANKER MANUAL CH. 09 MAINTAINENCE OF CARGO EQUIPMENT. Rev. No. 1 Date 15-Apr-16 Page Page 1 of MAINTAINENCE OF CARGO EQUIPMENT

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1 Page Page 1 of MAINTAINENCE OF CARGO EQUIPMENT To ensure safe and smooth cargo transfer and tank cleaning operations, cargo handling and tank cleaning equipment must be maintained as per maker s instructions and as per company procedures. Maintenance tasks and Maintenance Intervals of the equipment listed below are detailed in the Planned Maintenance System and interval as stated in sec 9.8 and are to be complied with: 1. Cargo Tanks 2. Cargo Pumps 3. Cargo and Ballast valves 4. Cargo and Ballast lines 5. Cargo Hoses 6. Vent Lines and Vapour lines 7. IG / N2 lines 8. P/V valves 9. Emergency shut downs 10. Vapour locks 11. Fixed and Portable Gauging systems (including UTI tapes) 12. Temperature and Pressure sensors 13. High level and overfill alarms 14. Flame screens 9.2. MAINTENANCE OF CARGO HOSES Cargo hoses are to be properly used and maintained in good condition as per maker s instruction. The cargo hose compatibility chart should be readily available with the Chief Officer in CCR and same is to be referred prior using cargo hose for intended transfer operation. Hoses should be retired in accordance with defined criteria. This guidance also applies to any tanker s cargo hoses used for tanker/shore connections and any other flexible hose connected to tanker or shore cargo systems, for example a jumper hose at the end of a ramp serving a pontoon berth. The owner of the hose should attest that any hose provided is certified, fit for purpose, in good physical condition and have been pressure tested.

2 Page Page 2 of 14 Markings to be made on the cargo lines and hoses: 1. Pressure test date and validity. 2. MAWP pressure of the lines of hoses. 3. Serial number of the hose where applicable. 4. Operating temperature of the hose Custody of Hoses 1. The hose should be cleaned up properly and drained out completely. 2. Store the hose in straight line raised off the ground preferably in a cool dark area. 3. Visually check any damage on inside and outside of the hose. (Displacement of the wire, tear, abrasion and any other abnormal features) 4. Never use hot water above 80 C when water is used for cleaning. 5. When live steam is necessary for cleaning, the hose must be open ended, vertically raised and limited steam should be allowed to pass through the hose to avoid damage to the inner lining. (Never blank the end of hose during cleaning by live steam) 6. After cleaning and draining, the hose should be blinded on both ends Precautions before transfer 1. The cargo hose must be inspected and approved by the cargo surveyor for Cleanliness prior being used for cargo transfer. 2. The cargo hose must be supported at appropriate points with the slings provided. 3. Support the hose near manifold connections. 4. Protect the hose against sharp edge. (e.g. jetty edge, ship s sharp upper structure, etc.) 5. Never allow sharp bends during cargo transfer operations. 6. Never allow hose to droop between ship and jetty/ship Withdrawal before service When the hose shows any of the following deformation, such hose should be immediately condemned, clearly marked and stowed away from other hoses.

3 Page Page 3 of Cutting of outer wire. 2. Leakage from hose body and hose ends (between ferrule and hose shank). 3. Wide range of deformation of outer wire and hose body (kink). 4. Heavy displacement of outer and inner wire. 5. Cuts and tears of outer cover to such extent that inner film appears. In consultation with the hose manufacturer, retirement age should be defined for each hose type to determine when it should be removed from service, irrespective of meeting inspection and testing criteria. The temporary elongations at which smooth bore rubber hose assemblies should be withdrawn from service will vary with the type of hose assembly construction, such that either: a) The temporary elongation, when measured, should not exceed 1.5 times the temporary elongation when the hose assembly was new. For example: Temporary elongation of new hose assembly: 4% Temporary elongation at test: 6% maximum Or b) For hose assemblies where the temporary elongation of a new assembly was 2.5% or less, the temporary elongation at the test should not be more than 2% more than that of the new hose assembly. For example: Temporary elongation of new hose assembly: 1% Temporary elongation of old hose assembly: 3% maximum. Or c) Elongation - If permanent elongation exceeds 2% of the overall length of the hose, the hose should be retired from service

4 Page Page 4 of 14 Handling of Cargo hoses

5 Page Page 5 of TANK CLEANING EQUIPMENT On chemical tankers care & maintenance of tank cleaning equipment is one of the most important aspects of operational maintenance. Equipment that has been properly maintained and cared for will give reliable and trouble free service resulting safe, smooth and efficient tankcleaning operations Tank cleaning Hoses Hoses should be handled with care and kinks and twists should be avoided. 1. Hoses should be clearly marked. 2. The electrical continuity of hoses should be checked regularly and recorded. Defective hoses should be removed from service and discarded. 3. Couplings should be checked and tightened as required Tank cleaning Machine 1. During operations machines should be checked to ensure that they are rotating freely and operating as designed. 2. Check that nozzles are not clogged. 3. Check that there are no loose parts that could drop off and cause a spark. 4. Carry out overhauls as recommended by the maker using appropriate spares. 5. All wear parts should be changed at the recommended intervals High Pressure wash Machine 1. Check that all hoses and connections are in satisfactory condition and that there are no leaks or soft spots. 2. Carry out routine maintenance in accordance with maker s instructions and renew all wear parts at recommended intervals. 3. High pressure wash machines should always be stowed in sheltered area Mucking Machine 1. Check that the wire and hook are in satisfactory condition. If the wire has broken strands then it should be replaced at once.

6 Page Page 6 of Carry out routine maintenance in accordance with maker s instructions and renew all wear parts at recommended intervals. 3. Check the brackets and mountings for any cracks or fatigue Portable Gas freeing fan Check that the impeller is turning smoothly without any wobble or imbalance and that the blades are not touching the sides of the casing. 1. Check that there are no loose parts. 2. Check that all couplings are tight. 3. Check condition of supply and discharge hoses and repair / renew as necessary. 4. Check the condition of vent chutes. These should be free of holes and gashes and the securing arrangements should be in good order PORTABLE SUBMERSIBLE PUMP 1.Check that all hoses and connections are in satisfactory condition and that there are no leaks or soft spots. 2. The flexible hoses are filled with hydraulic oil. Drain off approx. one cup of oil from the hoses before storage (when disconnecting from the main system). Control bend radius for the flexible hoses during storage (min 800 mm). 3. Confirm that the units are safely supported, and check that the snap-on coupling and starting head/flow control valves are greased and protected. 4. Carry out routine maintenance in accordance with maker s instructions and renew all wear parts at recommended intervals. 5. Try out the pump every 3 months, and maintain records in PMS PURGING COFFERDAM Submerged cargo pumps are to be tested for leakage of their mechanical seals and cofferdam with compressed air of suitable pressure as per the maker's instruction (about 2.0kg/cm2). The test is required to identify the amount of hydraulic oil or cargo leaking from the mechanical seals into the cofferdams.

7 Page Page 7 of 14 The test is carried out on the following occasions unless specified otherwise by the pump manufacturer s manual. a. After completion of cargo tank cleaning and before loading b. 1 or 2 days after loading c. Everyday if excessive leakage is detected a) and b) d. Before discharging e. After discharging Results of tests must be recorded in Cargo pump purging log form (CT 14) and submitted to Company. After the leak test, the cofferdams are to be kept pressurized with the tank test air, water etc as specified in the pump manufacturer s manual How to purge the cofferdam 1. Place a suitable container underneath the exhaust trap to collect the leakage. 2. Check that valve and bottom of exhaust trap is not clogged by residue after last purging operation. Stick up with a pin if necessary. 3. Check that the drain hole from the relief valve on the purging valve block is open. Location design of purging valve is different for the various pump types. For technical details, refer to the pumps service manual. 4. Connect air or inert gas supply to the snap-on coupling on the purging valve. 5. Drain the supply line for condensed water Purging Precautions NOTE: To prevent damage from dangerous cargoes, take necessary precautions, wear appropriate PPE and avoid contact with drain from exhaust trap. 1. Open valve on air/inert gas supply line 2. Check that air/inert gas is coming out of the exhaust trap vent line. (Cofferdam is open) 3. The relief valve on the purging valve block is set to an opening pressure of bar, so a small leakage here is normal. 4. Purge cofferdam in several sequences if required. 5. Drain exhaust trap between each sequence. 6. Disconnect air/inert gas supply 7. Close exhaust trap drain valve

8 Page Page 8 of Measure the amount of leakage, -evaluate and log the purging result Evaluation of the purging result CARGO LEAKAGE 1. Cargo in the cofferdam can come from shaft seals, flange face seals in pipe stack/pump head or damage (cracks) on the pipe stack/pump head. 2. A small leakage rate over the shaft seals up to about 0.5 L/day during pump operation is normal, and replacement of seals should not be necessary with this leakage rate. For short periods of time, higher leakage peaks can occur. 3. The leakage rate is also dependant on the type of cargo. Some cargoes like naphta, condensate etc., penetrate the shaft seals more easily than lub. oils, vegetable oils and other viscous cargoes. If the leakage rate is up to about 2 liters/day, the pump must be purged a couple of times daily, and inspected as soon as possible to find the reason for the leakage. 4. Intensify the purging if the leakage rate is increasing above acceptable level. If this is not keeping the leakage under control, close the hydraulic service valve. Do not operate the pump, use the portable pump to discharge the cargo. The development of a cargo leakage can be followed if purging is done according to specified intervals. Thereby maintenance work can be planned, and unexpected shut down due to leakage can be avoided Hydraulic Oil Leakage Hydraulic oil in the cofferdam can come from shaft seals, flange face seals in pipe stack/pump head or damage (cracks) on the pipe stack/pump head. A small leakage rate into the cofferdam up to about 10ml/h (0.25 L/day) from the mechanical oil seal or lip seal during pump operation is normal. For short periods of time, higher leakage peaks can occur How to detect air in the system Cargo Pump will not start from remote Level variations in the hydraulic oil tank at different system pressure. Back flow to hydraulic oil tank during stand still Possible Yes Yes

9 Foaming in the hydraulic tank Page Page 9 of 14 Yes Oil sample milky /white, or air bubble mixed into the oil Yes Abnormal noise from hydraulic pumps or motors. Possible Uncontrolled pressure variations (hunting) during operation. Possible Pressure peak shock in the system during start/stop of consumer Possible

10 Page Page 10 of The Ten Commandments 1. Purge regularly 2. Dismantle a pump only after identifying the problem. 3. Pressure test the pump, cofferdam and pipe stack using the kit 4. Use genuine spares 5. Use pump performance curves to establish condition of the pump 6. Do not increase system pressure more than 15 bar above the highest consumer requirement. 7. Avoid air (like plague!!) 8. Keep oil clean 9. Send oil samples for analysis regularly and never mix oil grades 10. Implement a planned maintenance system for the entire cargo handling system 9.6. CARGO TANK VAPOUR TIGHTNESS TEST Code of Federal Regulations (CFR) requires tanker vessels to issue a vapour tightness certificate with the code. Vapour tightness This is to be documented using the form "OP-CHEM Vapour Tightness Certificate" Following method should be used for the purpose of carrying out the test. 1. P/V Valve to be checked for proper functioning prior doing this test. 2. Keep all openings shut. 3. Install a U-Tube or a Compound Gauge on the PV Stack 3. Pressurize tank using Compressed Air or Nitrogen 4. Let the tank pressure come up to 1250 mm WG but no more than the pressure of the lowest pressure relief valve setting. 5. Openings to be checked for leakage using Soap solution (Apply soap solution to all openings, flanges and welding seams leakage will be visible by means of soap bubbles. 6. Once the pressure is obtained, the dry air or inert gas source shall be shut off.

11 Page Page 11 of 14 At the end of one-half hour, the pressure in the Cargo tank and piping shall be measured. The change in pressure shall be calculated using the following formula: P=Pi-Pf

12 Page Page 12 of 14 Where: P=change in pressure, inches of water. Pi=pressure in tank when air/gas source is shut off, inches of water. Pf=pressure in tank at the end of one-half hour after air/gas source is shut off, inches of water. The change in pressure, P, shall be compared to the pressure drop calculated using the following formula: PM=0.861 Pi L/V Where: PM=maximum allowable pressure change, inches of water. Pi=pressure in tank when air/ gas source is shut off, psi. L=maximum permitted loading rate of vessel, barrels per hour. V=total volume of product tank, barrels. If P < PM, the vessel is vapour tight. If P>PM, the vessel is not vapour tight and the source of the leak must be identified and repaired prior to retesting. In order to maintain vapour tightness the following should be checked and maintained in good condition. 1.Packings on tank domes, butter worth openings, level gauge fittings. 2.Tank securing arrangements 3.Cargo valve and drain valve integrity 4.P/V valves 5.Vapor locks 9.7. THERMAL OIL HEATING SYSTEM Flushing of heating system is only required prior to carrying out any maintenance or renewal of thermal oil. Care shall be exercised to ensure that the system is free of foreign materials such as welding waste, rust, dust, water etc to avoid thermal oil contamination. After completion of the maintenance, the system shall be filled with adequate quantity of fresh oil, sufficient to fill up the system and this fresh oil shall be re-circulated for several hours at 500C to 600C. Drain this oil completely and then top up the system with fresh oil.

13 Page Page 13 of MAINTENANCE ROUTINES Within this particular section maintenance routines are required to maintain the cargo equipment operational. The Master is responsible for ensuring that these are carried out at the specified intervals described with these procedures for those vessels which have a computerised Planned Maintenance System this work is to be recorded electronically and a printout provided for quick access for any inspector who required this information. The following items are to be contained in the maintenance records. Item Electrical bonding check on transfer hoses Electrical bonding check on portable tank cleaning hoses Pressure testing of transfer hoses** Pressure testing of cargo, and bunker piping (1.5 x WP) Pressure testing of heating coils Air pressure testing of sea and overboard valves Pump trips and emergency shutdowns Cargo and ballast pump safety devices Function testing and pressure testing of cargo valves Inert gas safety devices checks and operational tests Inert gas system inspection and maintenance including scrubber Frequency Each operation Each operation Each operation As per PMS Each operation Each voyage 6 months Each operation Manufacturer s instructions Test of pumproom bilge alarms Test of cargo and ballast tank high level alarms and sirens Purging of submersible pumps operation Inspection and examination of cargo, ballast and void spaces Run of test conditions of loading computer Weekly Each operation Before / after each operation 06 months 3 months Overhaul and cleaning of P/V valves Cleaning during each tankcleaning/overhauling & Calibration every six months

14 Inspection of flame screens within cargo systems Inspection of flame screens within ballast/bunker systems P/V breakers Deck seals I.G. non-return valves / Block and bleed valve Overhaul and inspection of tank gauging equipment Opening up and cleaning of Cargo Pump strainers Opening up an d cleaning of stripping pump strainers Opening up and cleaning of ballast pump strainers Check of tank cleaning machines Calibration checks on portable gas measuring equipment (Recorded in Safety Set) Calibration checks on fixed gas measuring equipment Calibration checks on pressure gauges Calibration and test run of ODME Calibration check of hermetic temperature functions Annual independent calibration of hermetic gauges De-contamination shower function Cleaning of tank radar systems transmitters Mooring winch brake testing Tank Tightness Test Cargo Pump Performance Test Page Page 14 of 14 3 months 6 months Manufacturer s instructions 6 months 6 months Each voyage 3 months 1 months 1 months Monthly Prior to Each operation Prior to each Operation 3 months As per PMS As per PMS Portable submersible pump to be tried out 3 Note** : Transfer hose to be tested once in 6 months if the service period of the hoses is above 5 years