Monday, 7 May 2012

GOODIES ON NEW BUILD CHEMICAL TANKERS - CAPT AJIT VADAKAYIL



     PREFERRED ON NEW BUILD ANNEX 2 TANKERS.

      THIS LIST WILL MAKE A HARDCORE CHEMICAL PARCEL TANKER MAN DROOL


1)   We have 2 deck tanks amidships. Both are entered in the IOPP certificate as Annex 1 tanks and are painted epoxy. It would have been better if one was SS and included in COF. On chemical tankers we like to take the manifold first foot sample at load port with the manifold valve shut. Quite often the terminals give bull that the pump they use is a positive displacement pump ( like screw pump ) so that we cannot reject the shore line content. Once the cargo is inside the tank, it becomes a ship’s first foot failure. Ship in such a screw pump scenario can use a Y piece and loop the first few shore line content into the deck tank, instead of taking it in the cargo tank. On XXX in XXX Mississippi , the styrene shore pipeline was in sun’s heat and was about a kilometer long. Imagine a ship’s tank polymerizing at sea, due to shore fault.

2)   The deck tanks bottom must be V shaped for decanting possibility, when ship is rolling at sea.

3)   Nowadays nitrogen padding using 99.99% is done with ship’s nitrogen plant—like what we did in Indonesian ports.  The 99.99% option uses a storage tank, which shuttles between 8 kg to 4 kg. The deck output comes at 0.2 bars into the small diameter nitrogen pipeline. The compressors cut in and cut out every few minutes, considering some tanks are slack. This overheats the heavy compressor motors. This also takes the whole day. Best is to have a membranes in series option ( like what we have ) and get the nitrogen into the VRL. And from this line send it into individual tanks via the purge pipe stub.

4)   The deck tanks should be designed to take the manifold drip tray content by gravity—without use of pump. A sudden down pour in tropical countries with lub oils inside the drip tray will go overboard.  Even half a litre overboard will create sheen over the entire berth area, which can be quite misleading when it comes to fines.  During recession times all like to collect fines. No small wilden pump can cope up, especially when the manifold trays are made for even keel conditions—and this is never the case practically.

5)   Purge pipes must be large diameter like on XX—and separate and far away from the PV tank dome orifice and even the catwalk . When shore gives nitrogen blow at high pressure / volume the purge pipe cover can be unbolted to give a secondary safety relief—to prevent cargo tank bursting.

6)   UTI tubes must be of large diameter so that high MP cargoes do NOT choke it. This makes it possible to put larger perforations all over the tube from top to bottom.

7)   On chemical tankers we do NOT trust double or triple valves or even hundred valves in series. We trust only empty space – which means a removable spool piece with 2 blanks.  Fancy fixed spool pieces which are lifted and lowered in position , can create mistakes. The air gap must be there to see. Yes this means someone has to go to a store and bring the spool piece to connect to the pipe, and then stow away the two blanks which will be removed. Extra work—but safe.

8)   The Annex 1 and Annex 2 connections in the pump room must have only ONE single elbow. This means at no time can you have Annex 1 and Annex 2 overboards running at the same time. This prevents monkey business.

9)   The Annex 2 under water overboard discharge line must have a easy spectacle blanking arrangement just inboard of the overboard valve. Sulphuric acid carriers have the Annex 2 overboard line from the overboard valve to deep load line holed and patched up . Salt water and dilute Sulphuric acid chomps away SS and welds.

10)    ODMCS which uses soap solution spoils the annex 1 slops. Excess soap and bubbles in the slops will cause the annex 1 slops to be rejected. Most slop reception party recycles the stuff. Soap is annex 2 .

11)    Never ever go for Japanese Kosaka deepwell pumps, as they do NOT have a jockey pump which prevents a free flowing dense cargo like Sulphuric acid entering the hydraulic oil. Pressurising the cofferdam with air/ nitrogen is best achieved only in sweet Japanese dreams. And only stupid souls have a FIXED air line connected to the cofferdam. If air can go into cofferdam—liquid can also come into air line—depending on who has more power.

12)    Use diffusers at drops for recirc. The jet holes should be tiny and sufficient to achieve the homogenization . Such diffuser fitter tanks of course must be able to load cargo via the deep well pump sump. This means that a molasses filter at the manifold is a must. We cannot afford to have both the diffuser fitter on the drop line and the framo impeller choked with debris.

13)    Ships should either have Thermal oil heating ( like on XX ) or possibility to send HOT fresh water into steam coils via tank cleaning heater and put it back into the slop tank in continuous recirc mode. Poison water cannot be sent into engine room hot well via steam return line .

14)    On XX 11 S –just one tank can be used as annex 1 slop tank. The ODMCS reject should go by fixed pipe to manifold so that it can be looped to any tank—like on XXX.

15)    Horizontal corrugation bulkhead tanks are stronger than vertical corrugation ships like XX and XXX. These ships can take higher load density. This means one of the fixed tank cleaning machines must extend further to the bottom of the tank to avoid shadow sectors.

16)    A chemical tanker which does NOT have a double defence packing ( tank dome / butter worth port ) is a very poor ship. The outer packing should be Viton and the inner should be PTFE. The bolts be longer to enable another nut to be put as check nut for water sensitive cargoes like sulphuric acid—which can sink the ship.

17)    At the building stage it must be told clearly to the yard that there cannot be any NON inert gas backed secondary SS welds. These welds get oxidized and eaten up and causes black tattoo on SS.  Sensitive cargoes like wine can never ever be carried on such ships.

18)    The framo deepwell pump discharge pipe must slope towards the manifold like on XX and XXX. This avoids the need to fit fixed small dia super strip lines running piggy back at the manifold. While dischg cargo slides down by gravity to manifold. The common collector must be below the level of the manifold stack, for easy blow. There are so many XXX ships like our XX ships where morons have not thought of the laws of physics that air always finds the highest point and liquids always find the lowest point..

19)    Ballast SBT tanks should have an independent educator for stripping. Nowadays with fast turn around with heavy SG cargoes ship may not have sufficient trim at berth. Eductors strip tanks even when ship is rolling at sea. It can be used to gas free tanks too.

20)    The aft most ballast tank must have list correction pipelines in ballst pump room like on XX and XXX. This means aft most tanks P/S have pipelines between the common bulkhead master and the ballast pump— with suction valves situated inside the pumproom.   Fast list correction means you suck from port wing tank and put it direct into the stbd wing tank . This is most important when ships load several heavy parcel cargoes.

21)    With modern mooring hawsers being very light ( unlike their polypropylene ancestors ) it becomes necessary that a small chemical tanker must have slightly oversized mooring bitts.

22)    Split drums take care of the mooring winch brake rendering mathematics. Otherwise it is all officially sponsored bull.

23)    Chemical tankers who trade in freezing countries with high MP poisonous cargoes must have sufficient copper steam tracer tubes and silver insulation lagging to parcel vital pipeline areas which get frozen at manifold. This can save crew injury. This is important for ships like XX / XXX whose delivery pipelines slope towards the manifold.  Cargo cannot be blown uphill as air skims on top on large dia pipelines —imagine loading Phenol or HMD from barges in minus 20 deg C.

24)    Every cargo tank must have a check valve on deck, so that recirc can be done with a spider/ octopus. Even while tank cleaning the drop line has to be flushed and the pump wear rings have to be squirted through.

25)    Tugs T marks on shipside on XXX are all at transverse bulkheads, which will yield.  Only horizontal corrugations will resist.

26)    Ships which carry high MP cargoes like palm oil fatty acids over RIMING areas like north of Aleutian chain ( favorite play ground of stupid wiz kid weather routers who have never had salt spray on lips )  must have anti-riming devices on PV valve cones.

27) XXXhas only 3 HO tanks. With SECA rules and commingling rules—the bare minimum is 4. Or you waste money taking costly bunkers and making inconvenient bunker port calls. Never deprive a ship of the comfort of safe reserves. This is NOT about money—it is about human lives when a typhoon looms.

28)    On XX we had all bunker tanks aft. On XX we have a HO deep tank on forecastle. This means steam on deck. It is stupid – to have a common steam return line back to the hot well in engine room. All cargo tank steam return coil manifolds are connected to the same steam return line.

29)    On XXX we have 13 cargo wing tanks and 5 ballast wing tanks underneath.  Proper tank washings require cold ballast interface removal. Even ballast water exchange needs some leeway.

30)    Cargo hoses must be respected. A ship without a proper cradle is like a cheapskate mother who denies her baby of a cradle. Cradles must be convex to be self draining. Polypropylene hoses are affected by UV of sunlight.  This means there must be a hinged cover. SS spirals on hose should NOT touch steel. This means wooden / Teflon sheathing.  Wood can catch fire when in contact with strong oxidizers and get destroyed..

31)    The common collector at the manifold should be able to be spectacle blanked into 3 sections—instead of one continuous one. This means all manifold pipes must be staggered into 3 groups –instead of a continuous 1 to 13 port and stbd. This also means 3 drip tray segregations for cargo compatibility. Is this NOT in tune with the essence of IBC code?

32)    A SS chemical tanker must have two fixed SS nitric acid storage tank of around 1200 litres each.  The USCG does NOT allow nitric acid to be stored in drums.

33)    Ballast pumps in pump room must have auto strip facility.

34)    A chemical tanker must have a bow thruster. The forepeak ballast tank must have sufficient capacity to keep the impeller well submerged.

35)    A dump drain tank between the aft most tanks just about 1 metres deep , but below the level of the main deck with inerting pipelines.

36)    Eye wash shower must have a proper thermostatic mixer.

37)    The 99.99% nitrogen storage tank with delivery on deck to small dia nitrogen lines must basically be a 7 bar pressure blow to blow the stack or cofferdam.

38)    The nitrogen block and bleed dump -- and super rich membrane waste oxygen dump must not be carelessly channeled at deck level —like on XX.

39)    Fresh water generator minimum 20 tons capacity. The eliminated the need for DI water / Demi water generators.

40)    Removable spool piece fixed connection from small slop tank dischg to tank cleaning line.  Tank cleaning solutions can be mixed in the tank —heated up by steam coils and then channeled into fixed tank cleaning machines—to beat direct injection systems or recirc system , where clean areas get dirty..

41)    Provision for nitrogen padding ballast tanks, for cargoes like propylene oxide.

42)    Sprinkler coolers on main deck.

43)    Minimum 3 nos VRL like on XXX.

44)    Dedicated high volume low pressure ( 8 kg ) deck air compressor with own storage bottle accumulator.

45)    One SS hose with small nozzle SS butterworth machine for nitric acid passivation. Smooth tanks means good grade cargoes . Free iron accelerated polymerization.

46)    Each PV stack with its own pressure guage fitting housing.

47)    Tank cleaning heater outlet temp and pressure guage in CCR. Tank cleaning pump control is in CCR to vary pressures and temperatures.

48)    Anemometer repeater in CCR.

49)    It should be possible to fit a portable air blower at the manifold to extract air from the tank bottom via the cargo drop .

50)    Graco barrel pump tank cleaning solvent injection point after tank cleaning heater on deck.

51)    Chemical dosing tank 1.5 cum capacity ( high level ) to gravity feed tank cleaning line pump on suction side.

52)    Training video for particular deep well pump model overhauling.

53)    Predictive maintenance systems . There are only 24 hours in a day out of which rest hours must be subtracted. Planned maintenance systems think that there is 48 hours per day with NIL time required for human beings to rest—with unlimited budget.

54)    Minimum 800 tons TCFW capacity.

55)    A better and intelligent cascade system cum siphoning drum just before the steam return line meets the hot well in engine room—this must understand that chemical takers load cargoes which float on water like lubes, which are soluble in water like ethanol and which are insoluble in water but heavy/ light, or partially soluble.

56)    Steam blow reducer at manifold.

57)    4 orifices at every manifold pipe outside the valve. TOP orifices - pressure guage,  compressed air blow, and high volume steam blow of larger dia. BOTTOM orifice for drain cock and sampling.

58)    One BOTTOM orifice at every manifold pipe inside of the valve  for draining manifold in case of loading high MP cargoes in freezing weather from barges . Assume no superstrip after dischg pump stack blow,  of sloping to manifold pump delivery lines ( see item 18 ).  If item 18 slope is NOT there then this orifice has to be on TOP.

59)    Proper hanging cradle in FP store for portable framo pump taking care of bend radius of flexible hyd pipes.

60)    Tank domes must have 2 glass view ports with manual rotary screen wipers.

61)    Stern line for non-toxic cargoes with drip tray having drain tank connection- and PV vent leading away from accommodation.

62)    Graphite bursting discs fitting arrangement on PV.

63)    Dedicated wall wash lab with fridge and washbasin. Methanol must be stowed outside the accommodation.

64)    Power pack hyd piping arrangement on deck should be vented at the highest point—and hence an arrangement for that.

65)    A proper VRS manual. Never seen one so far. The graph must have on X and Y axis—friction loss in mm aq VERSUS load ate in cum/ hr – and the LAMBDA curves of vapour /air density at 45 dg c in kg/ cum.  Several such pages should exist for various loading condition combinations including common manifold and Y pieces for small/ big tanks using the 1 or 3 VRL lines.

66)    3 air driven portable fans. Small fans have 2 times the capacity of large fixed fan—time is saved.

67)    Large fixed vent fan must have steam heater, dehumidifier. In modern times tanks are mostly rejected due to condensation ( when cargo is NOT ready—surveyor is mafia ). Warm moist air will always condense on cold surface. Usually mindless ventilation creates MORE condensation.

68)    Portable educator for solvent steaming pipelines from manifold.

69)    Welding transformer in ford store. Return current cable should  used—or the hull current corrupts PLC and microprocessors.

70)    Ballast tanks must have means of checking cargo vapor. Most chemicals have higher VD than air.

71)    Helicopter winching area, is a must in modern times. Launches cost more.

72)    2 sampling lockers for incompatible chemicals , with steel trays.

73)    FW flush inlet to tank cleaning heater—to replace salt water in tubes with fresh water at the end of operations.

74)    ODMCS reject should NOT be channeled to a single dedicated slop tank, like on XXX. Rather it should be channeled to the manifold,  for where it can be put into any small tank , like on Colt.

75)    2 MOT ladders –big and small. First and last impression—safe gangway.

76)    Unribbed ( unfinned ) smooth exterior economizer tubes. No sparks after washing the tubes.

77)    Saucers instead of sunken sump pits beneath framo deepwell pump bellmouths.

78)    Drop lines in tank should face forward—to do TSUNAMI wave desedimentation of bottom—just before squeegeeing. ( for tanks NOT fitted with diffusers )

79)    Fixed ullage should be at centroid of tank. Online systems do NOT account for bunker and ballast tanks. So if manual trim and list is NOT fed in regularly, all outputs are wrong including cargo volumes and rates.

80)    97% and 98% stubs should be seen from the sight glass on the tank domes.

81)    Railings on ain deck should be recessed by 40 cms inwards.—or damaged by tug fenders when freeboard is too low.

82)    No unstreamlined structures of forecastle. There is NIL intelligence in this when ship has low freeboards. Speed has to be reduced even in moderate weather. A round structure is streamlined—example.

83)    Booster pump at the manifold –with air tight housing to prevent salt damage.

84)    Compressed air line and VRL drains at lowest point.

85)    Power pack should NEVER be in the forepeak store , like on XXX ships. The advantage of natural HEAD is lost when the forecastle in inaccessible due to heavy rime in freezing seas. The heart of the ship is dead. Jockey pump provided the head on Framo powerpacks , unlike Japanese designs without jockey pump.

86)    Sufficient closed chock fairleads for STS—has to be roller type ( great lake types ) to prevent chafing .

87)    Midships illumination at manifold is a MUST. Manifold samples are taken at night too.

88)     In shore terminals which use submarine hoses at high back pressure—air blow cannot be done . The underwater pipe will get buoyant and burst. It becomes necessary to do INTERNAL STRIPPING—without stopping shore discharge. To facilitate this a common collector on both sides— is a boon. Imagine time saved in port. Imagine hard labour done by way of squeegeing reduced. Imagine ROB becoming less. Imagine deepwell pumps with less wear due to dry running. All for the want of an extra common collector on seaward side.

89)     VRL alarm test kit is important. ( +1600/ -350 mm aq)

90)    PV stacks on deck must be rigid. No vibrations, which will cause loss of nitrogen pad.

91)    PV cone must be operated by gravity NOT buy magnets. When the distance between magnets increase the magnetic attraction gets REDUCED by the SQUARE OF THE DISTANCE between them. So they rise at correct time—but sit down after the tank is almost fully depressurized. THIS HAS CONTRIBUTED TO SHIPS STAFF GETTING CANCER AT SEA. Ocean losses are due to this. Global warming due to ULCCs’ belching out gas at sea is mindboggling. These culprits making such mindless magnetic PV valves must have been imprisoned long ago.

92)    Urinal for crew outside accommodation. NO need for chemical contamination inside accommodation, every time someone wants to take a leak.

93)    Approved overflow orifices at shipside for ballast exchange. These valves will be 1 metre below main deck level in all SBT. Empty Re-fill method is time consuming and stressful for ship—and is a weather permitting procedure lest ships slams or gets a propeller trip.

94)    Larger drain holes in all SBT bottoms will reduce mud. Mud creates unpumpables and rust.

95)    With latest SECA/ commingling problems –ship must have minimum 4 HO tanks.

96)    With SECA problems , ship must have extra tanks for taking in low TBN lubes. Bore polishing of ME/ AE liners can cause disasters.  It just takes 24 hours to spoil the liner honing—when high TBN MECYL is used for low sulphur HO in ME.  XXX under XX management replaced 3 main engine liners in the first couple of months. This is mindless abuse by poor engineers. They had NO dang idea that an Alpha Lubricator has a sea mode and a manoeuvring mode.

97)    All deck ladder handrails should have 40 cm inserts of SS unpainted inserts to diffuse the static in the human body—such static sparks can be incendive—difficult to believe , right? Basically the human body is electrolyte in a leather bag—like a battery.

98)    All final drawings must have electronic format, to hold one copy in office.

99)    Modern SS chemical parcel tankers are chosen by charterers to carry Annex 1 products over conventional epoxy product carriers —as the PV lifting pressures are higher ( less ocean loss ?)  lesser ROB in sump , lesser discrepancy fights, no recovery time for tank lining after Gasoline, flexibility with parcels, lesser tank cleaning , less tank cleaning chemicals, less salt, lesser loss in pipelines, no IG soot and hence better tank dry inspection, no leaky tank vales due to PTFE seals etc etc. A lot of terminals use submarine shore pipes which cannot be blown. Water plug is required FROM ship after discharge . This means a connection from ships Ballast pump , taking water from SBT to connect to shore discharge line ( with a removable spool and a NR valve ). We cannot have backflow into the sea from high shore tank—which happens 50% of the time.

100)                        Double check nuts on steam coils in tank bottom . Single nuts get loose in vibrations and damage pump impeller causing dynamic unbalance , vibrations and stack cracks.

101)                        Service speed 1 knot higher that what is given in charter party. Better to get the pitch of the propeller measured by Yard—as they tell lies on the speed /rpm placard.

102)                        The lowest pH value ( acid side ) the epoxy tank in ballast tanks can take must be declared in writing by the paint manufacturer. They always tell lies or evade this issue. There are quick to declare the 14 pH base side

103)                        Deck catwalk gratings and clamps must be non corrosive .

104)                        All tank domes must be aft of tank above the sump so that a portable framo can be lowered at aft bulkhead.

105)                        Catwalk shelters must have a glass sighting hole.

106)                        Heating coil risers must be near tank ladder.

107)                        Every deck pipeline must have phenolic pad resin pads  on support –no metal to metal contact. Ugly weepings and galvanic corrosion holes.

108)                        Turning steam inlet main pipe by 180 deg must be considered att building stage.

109)                        A coil in hot well. Can be used dually to heat or cool-depending on the need. Energy conservation means less bunkers burnt in boiler furnace—basically burning dollars.

110)                        Hyd system for winches and windlass should be preferably a low pressure system—NOT from the Framo HP lines.

111)                        Funnel spark arrestors at 60 deg bend facing aft.

112)                        Polyethylene lining of ER sea water pipelines –under the load draft waterline. Galvanisation works for just one year.

113)                        Loadicator to have harbour condition. Excess safety margin at port is NOT required.

114)                        Sea trails must be done with 380 cst and NOT golden gas oil . They may do the PRE- sea trials with golden gas oil.

115)                        If a tug mark T is put on vertical corrugation bulkhead , it just crumples. Tugs are strong nowadays.

116)                        Nitrogen plant to have stencher / ozoniser.  Ozone lines can be fed to the vegetable room from an accumulator bottle. Cheap retrofit. Nitrogen is odorless and colorless and is a great danger to crew

117)                        All heat exchangers designed for 20% fouling margin.

118)                        Fixed gas freeing fans to give purge pipe an exit velocity of  >30 mtrs/ sec.—even though they have been fitted with flame arrestor SS mesh.

119)                        Galley blowers 2 speeds. Reduce speed at port to prevent vacuum in accommodation.

120)                        Presently all 26 tanks have just one UTI sampling point. Sampling takes at least 4 hours AGW, operated by experts. Every tank must have minimum 2 sampling points to cut down this time by half..

121)                        Ballast pipelines GRE—without couplers.

122)                        A sewage holding tank. Local rules are getting strict. Don’t expect master to pay bribe to corrupt port authorities—as he will NOT pay a bribe for himself.

123)                        High catwalk-with high level VRL spools . Good for sensitive nitrogen plant membranes .

124)                        Radar ullaging requires NIL maintenance – and are accurate—unlike floats, which get holed, need density correction, viscosity correction with high MP cargoes , hit the top stopper while pitching and smashing up the delicate magnetic reeds inside.

125)                        Ballast valves must be situated in adjacent tank for ease of repairs.

126)                        Overflow from service to settling tank can keep the purifiers running continuously.

127)                        FW system on deck well insulated to prevent freezing.

128)                        Steam ejector system to produce FW at anchorage.

129)                        UTI tube extension must always be on aft bulkhead.

130)                        Common collector at manifold must always be below the level of the manifold valves. There are many Japanese ships ( like our XX ships ) with collector on top—which makes shore blow impossible. Liquid always collects at lowest point.

131)                        Minimum 2 ballast pumps.

132)                        Gas free fixed fans , electrically powered in aft pump room. They must have a labyrinth path for air inlet to shake off salt water spray. The more you bleed the juice from Framo power pack for extras like crane, gas free fan, winches, ballast pump etc—the more the dischg capacity is reduced.  At full capacity 3 power packs can run just 4 cargo pumps.

133)                        Cargo PTFE gaskets must have bolt holes—they must not be inserts—which can get displaced with surge pressures—considering that we deliberately put compressed air into the pipelines to blow the pump stack after stripping..

134)                        Manifold platform area must be huge—sufficient to land stores, store TC chemical drums, 2 nos Suez canal boats etc

135)                        Free fall LB aft .  Side lifeboats ( enclosed type ) are NOT safe and they eat into accommodation space. Result?—no toilets—no stores—rat hole cabins—less morale.

136)                        Exhaust gas economizer capable of dry running.

137)                        Jockey pump should be powered by Eng generator—also SCBA compressor, and one MAC ( very little KW ) for dead ship starting.

138)                        Nitrogen block and bleed must NOT dischg nitrogen gas into working area like on XX . Also enriched oxygen discard from membranes—MOST dangerous with funnel sparks

139)                        Sulphuric acid load stress shear force conditions must have small tanks all around—to be wasted by keeping empty.

140)                        In case of bunker tank forward—separate return line. Using same chemical steam return line is VERY POOR THINKING by pretenders.

141)                        SS blanks for steam INLET and steam RETURN coils for all tanks.

142)                        Provision for variable high temp alarms settings for loading cargoes adjacent to tanks ( within 10 degrees of BP ).

143)                        Conection from VRL to purge pipe stubs by flexible hose—to use 95% mode in membrane series flow – to speed up the padding process . We rarely carry cargoes like Hexene 1 which requires extremely low oxygen ppm.  99.99% mode puts the nitrogen into small dia line—NOT VRL.

144)                        Thermal heating tanks which usually load poisonous cargoes like Phenol/ HMD etc—must be far away from accommodation. NOT at aft tanks 12 w 13 w , like on XXX .

145)                        Ships carrying high MP cargoes in winter can load to 98% only if tank domes which have the PV orifice , are situated at the centroid—NOT at aft bulkhead.







CAPT AJIT VADAKAYIL ( 29  years in command )
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