Posted by : sanjay swain Saturday, October 26, 2013



DRY DOCKING
·        the major event
·        preparing the vessel for the next 30 months
·        cost

DRYDOCKING MAINTENANCE ALTERNATIVES
·        crew
·        traveling squads
·        shore assistance
·        compare with shipyard
·        heavy work involving high lifts  transportation
·        lowest cost

DRYDOCKING SPECIFICATION (most important document)
·        terms/conditions
·        description of all jobs
·        compiling the specifications as  early as possible

DRYDOCKING SUCCESS FACTORS   (knowing the vessel)
·        good and complete specification
·        planning
·        controlling the yard
·        adequate resources

DRYDOCKING THE SUCCESSFULL DD
·        the specification to cover between 80-90%  of all work
·        no major extra cost
·        within the stipulated time and estimated  cost

DRYDOCKING PREPARATION FOR ENTRY
·        vessel to be free for hot work and   enclosed places to be ventilated as required
·        bunkers / f.water / ballast etc. be suitably distributed to achieve   suggested trim.
·        works in specification identified / marked.
·        supervision duties decided and agreed to.

DRYDOCKING SURVEYS
·         a list of all items to be surveyed is kept ready
·         list of all certificates expiring is ready
·         list of conditions of class to be dealt with is clear
·         list of new applicable regulations to be attended to is available.
·         modifications /fabrications if any as per new regulations should already
·        be in the scope of repairs
·         liase with the surveyor and agree on the scope of inspections / duration of inspections.
·         to keep surveyor informed about the docking surveys and get a list of recommendations at the earliest for completion of statutory  certificates.
·         get surveyor’s approvals for the scope of repairs involving class.


PRE DOCKING SURVEYS
• get the gauging reports verified and establish the scope of steel repairs.
• agree with surveyors’ action plan for crediting of cargo /ballast tanks   for (intermediate/special) surveys
• agree on testing procedures / repair procedures if any and press test of tanks as per    requirements.
• it is advantageous to plan to credit all tanks prior to docking, the trading pattern permitting.
• to credit max possible CSM items prior to docking.

DRYDOCK WORK SCHEDULE
ship staff and yard jobs are clearly understood / planned and carried out without interference
• yard jobs (in process and completion and testing) are properly supervised
• spares supplied to yard by vessel / arrival of new spares etc are properly  recorded and monitored
• decision makings are properly delegated
• onboard timings are suitably altered to get max   productivity.
• shipboard meetings are properly timed to continously   monitor the situation.
• repair teams if any are to be properly utilised and   effectively monitored

dry docking safety
• safety meetings involving yard and ship staff to be properly timed and well attended
• violations of yard guidelines are to be strictly discouraged (hotwork in engine room etc.)
• tank entries etc. are to be done strictly according to procedures and  personnel to be doubly careful while closing openings
• importance to be given to attire.
• extreme care to be exercised while turning engines/operating steering   gear/starting blowers/switching on electrical breakers/prior trials etc.
• systems are to be properly deactivated and rendered safe (depressurise  hydraulic lines/empty oil lines/drain  sea water lines etc)
• boundaries of fuel oil tanks are properly marked
• the tank drain plugs are properly marked / identified and protected from inadvertant opening.
• frame nos are suitably marked on deck/sides and bottom.
• vent pipes are suitably marked/identified.

drydocking economy    
• repairs done through afloat workshops are always cheaper
• most of the specialized jobs are   done thru subcontractors or representatives of OEMs with a surcharge.
• a repair team will always be cheaper if the materials can   be organized cheaply.
• you will loose a fortune if you need to do tank cleaning inside a yard.
• all additional work will be charged at a very high rate.
• the smaller the fabrication jobs/steel jobs on deck--the more   uneconomical it becomes.
• quantities of steel work/pipe work/hull painting etc are to be determined with respect to conditions in tariff like
           • minimum kgs per location
           • minimum meters per location.
           • charges for inway and access work
           • minimum surface (blasting)
           • minimum no of points per location (gauging)

• WATCH OUT FOR THESE DANGER AREAS
          pipe clamps
          transport to workshop
          machining/fabrication items
          cleaning
          ventilations / bilges / services.

 it would be cost effective to take a quote for the following
     - unshipment of rudder
     - renewal of carrier bearing with yard material
     - renewal of pintle bearing with yard material
     - standard tariff for o’haul of motors (kw basis) /pumps (kw basis)/pipes (meter basis)/ testing of pipes (meter basis) /testing of welds (meter basis) / supply of skilled and unskilled manpower (hourly basis) magnaflux / radiography and other tests / staging (tower and block/buildup of pits/reweld bottom plates

• best economy is an outcome of a tight specification

drydocking   commercial

the following important aspects are covered by   the contract document
•       time of completion
•       discount offerred
•       penalty clauses
•       repair specifications
•       repair specifications
•       payment schedule & redelivery of vessel
•       owners rights
•       yards responsibilty and limitations
•       guarantee
•       engagement of subcontractors and surcharge.
•       work done certificates
•       authority and owners representative
•       cancellation clause / terms
•       facilities to be provided to owners representatives
•       change of scope of repairs
•       spares and stowage
•       pilotage tugs etc for shifting for yards convienience
    •       the owners enquiry contains the conditions   of the owners
    •       the yards offer contains the yards rules and conditions
    •       the conditions in the yards offer stand valid even if they are
contradictory to owners   request once the vessel has been stemmed
    •       the areas of contradictions are to be agreed upon / thrashed out prior stemming the vessel.

drydocking technical -  corrosion protection
anodes
-       choice of the correct type and quantity of anodes.
-       replenishing of electrodes for impressed current   systems if fitted.
    -       protection of anodes while painting
    -       correct placing of anodes under guidance from supplier.
-       removal of old anodes

drydocking technical
• steel work
           - inspection of weld quality / fitups
         - keep track of the dimensions and locations (for commercial reasons)


• rudder
            - bush clearance
          - drop
          - sealing 0 rings for the taper surface of the pintles
          - proper cementing of palm bolts
          - water box closing plate water tightness
          - jumping bar /clearance
          - key ways
• propeller
       -  push up and pull up hydraulic pressures (push up curve)
      -  key ways
      - polishing

• anchors and chain-
      - gauging and reversal if reqd
     - cleaning of chain locker and insp


• HULL
      - gauging of stiker plates
      - build up of pits
      - wee out/gouge and build up weld seams of bottom   plates
      - inspection of drain plugs

drydocking technical (machinery)
• cleaning of coolers and heaters
• o’haul of large electric motors
• balancing of rotating equipments as reqd.
• o’haul of machinery as reqd
• recheck alignments of machineries if disturbed.
• remove deficiencies in automation and control equipmen as reqd.

drydocking instrumentation and navigating equipments
• callibration of electrical switchboard meters/other electrical and mechanical measuring devices
• o’haul of main breakers and callibrating safety trips.
• rectify deficiencies in navigating instruments
• rectify deficiencies in safety systems if any.

drydocking prior flooding(important items prior flooding)
-       all tank drain plugs are inspected and vacuum   tested after fitment
-       all anodes are functional
-       sea chest gratings etc are secured
-       correct ballast is taken.
-       inspect rudder (water box) / propeller /rope/ guard
-       all cargo/ballast tanks are clean from remnants of    steel work
-       cargo lines etc pressure tested / pumps are tried out
-       all tank valves (if remote operated) are tried out
-       hatch covers etc and other type of cargo gear are tried out and properly secured
-       all sea chests are properly purged of air
-       all equipment in engine room are tried out
-       main engines/boilers are preheated and ready for trials


drydocking sea trials
• sea trials
     - engines are run to required speed, movements are checked.
     - steering is confirmed to be performing satisfactory
     - stern tube oil is checked for maintaining level.

• the vessel may proceed to sea on   satisfactory completion in some cases


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