A03153 Sat, 4 Jun XXX 14:54
From: XXX MASTER
To :XXX TECH2 XXX Sent 6/3/XXX 1:56 AM
Date: Friday, June 03, XXX 12:53 AM Msg: A03153-54548
Path: \MASTER\SentBox@@@@@@@@\XXX
Sub : XXX/ Fw: Notice of newly issued "HSD-B11103" For HITACHI- MAN B&W Diesel Engines
Attach: HSD-B11103E .pdf scav air water condensation.pdf
chengr will give a reply--
this long email will make REAL engineers drool and fitter types mad --
dear XXX,
when XXX brains trust give fancy coloured graphs -- thumb rule: dont
trust it.
to read more about such stupid XXX graphs punch into google search
THE NAIVE SAILOR GPS -VADAKAYIL
let us imagine a scenario on north contender doing a voyage from
lae to madang at hot ambient temp 35 deg c and relative humidity
99% with heavy intermittent rain. the dew point should be 34.8 deg c.
will the mist catcher be able to remove all the water inherent in the
air released by the air compresssor side of the turbocharger?
absolutely not--
in fact if you look into the sight glass of the mist catcher it will
be continious flow like a open tap.
about 40% of the 4 tons of water ( surprised- right? )will evade
the undercapacity water mist catcher and find its way to the
scavenge air receiver-- where it will condense again.
of course there are drains to remove it ( see attachment of XXX
arrangement ) -- but these drains can get choked with sludge.
the condensed water from SAR/ underpiston goes directly into
the scav drain tank , which does NOT have a HL alarm --
and engineers may never get to know is the drain is choked. all
must know how to do THERMO CHECK at this drain using the fingers.
-- so far i have never seen a PMS which gives an iota of importance
to the all important scavenge drains . it deserves an check/ overhaul
every month.
-- and then the scavenge air receiver and the underpiston space become
swimming pools--from where water will be churned into the cylinders
with every blast before and after BDC via scavenge ports.
THIS WILL SHATTER THE PISTON RINGS.
in such a case it pays to increase the scav air temp to 48 deg c ( not
more ).
XXX should not worry about sulphurous acid-- this can come only if
the sulphur content is high.
our santos bunkers have 0.5% sulphur. in any case this acid serves to
clean the keechad from liner honed grooves, which act as reservoirs
for the mecyl..
as of today now we need to clean our aircooler ( 52 deg c ) - anything
more than 48 deg c and the main engine loses power.
in the april XXX meet 2nd engr XXX said that " the ME air cooler
covers are holed " .
there are special apexior coating available in the market to prevent
end cast iron covers of coolers geting holed by galvanic action/ or by
getting cavitation eroded.
now about adjusting the scavenge air temperature like the XXX want--
when i went to XXX for taking delivery of XXX-- from the
hotel XXX i shot off a email to tech dept from my private yahoo
email .
that you should make a tech superintendents standing instructions
for this new ship, of which this particular one must be
highlighted--
QUOTE: MAIN ENGINE SCAVENE AIR TEMPERATURE
MUST BE ADJUSTED WITH SEA WATER OUTLET VALVE--
THE INLET VALVE MUST BE 100% OPEN: UNQUOTE
as soon as capt vadakayil signs off from a ship -- all revert back to
adjusting coolers with INLET sea water valves. old habits die hard!
it is so dang easy to find the "tell tale history" -- as in this case
only the top inlet cooler tubes get choked.
water has this fantastic heat absorbsion/ dissipation capabilty if
the inlet valve is 100% open and return valve is throttled-- which
keeps 100% tubes chock-a-block with water.
this is this theoretical reason which enabled me to catch the
engineers happily pumping out XXX via the XXX into the
deck fire line into theanchor hawse pipe -- XXX. OWS was
used rarely in XXX ( XXX failed the vetting on XXX )-- this
could mean only one thing , right?
-- corrosion of air cooler fins means poor cooling -- most corrosion
of air cooler fins takes place , due to running sea water when ship is
alongside and stopped.
-- all STEAM connections to scav drains must be blanked. steam
rises --water falls.
-- modern theories are changing -- NOx is reduced by water mist.
bottom para:
it is common place to see engineers struggling over white hard scale
choked salt water cooler tubes --on all ships--all over this planet-.
this is like hitting your own feet with a hammer and then doing self
medication.
let us examine a simple tank cleaning heater in the ballast pumproom.
it has a shell which contains steam and there are finned tubes inside
containing flowing salt water, which has to be heated.
after the operations , the salt water inside the tubes is replaced by
fresh water-- OR blown with steam and drained.
is there any way the tubes can get choked with scale? -- pray?
never!
now let us imagine a useless chief officer in charge of operations.
after the use of tankcleaning heater , till the next opeartion -- say
after 3 months, the salt water remains in the tubes.
a leaky steam inlet valve means these tubes containing stagnant
salt water is geting heated from outside .
the next operation --the tankcleaning heater will NOT perform.
when the heater is opened out the tubes will be choked with hard
white scale.
SAF-ACID LEKHE AAO! PHATAPHAT!! -- same sad story,
again and again and again --
brgds
capt ajit vadakayil
master
mt XXX
" to extract the best from your team, get 'em emotionally involved "
-----------------------------------------------------
-----
From: Technical Team 2 XXXX Ship Management
Date: Thu, 2 Jun 2011 13:41 +0100 Msg: AMOS-324791481
Subject: Notice of newly issued "HSD-B11103" For HITACHI- MAN B&W Diesel
Engines
To: XXX - MASTER
To: XXX - MASTER
To: XXX - MASTER
Cc: Technical Team 2 XXX Ship Management
Good day Captain / Chief Engineer,
This SL on scavenge air condensation handling to minimise carry
over is important; revert back on the status
Kind Regards,
XXX
-----Original Message-----
From:XXX [mailto: XXX@hitachizosen.co.jp]
Sent: Thursday, June 02, XXX 3:22 PM
Subject: Notice of newly issued "HSD-B11103" For HITACHI- MAN B&W Diesel Engines
We are please to inform you of the following service data is newly issued
HSD-B11103 for HITACHI-MAN B&W Diesel Engines and alsoavailable
on our web site.
Please visit:
Home page address : http://hzds.aska.or.jp
User name : XXX
Password : XXX
XXX, XXX of Service department Hitachi Zosen Corporation, Diesel Engine Unit.
7-89,NANKO-KITA 1-CHOME,
SUMINOE-KU,OSAKA 559-8559, JAPAN
CAPT AJIT VADAKAYIL
29 years in command
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