Please identify the manufacturer (builder) of the main boilers of
passenger ship SS Norway.  Also the main characteristics of the boiler
design i.e. type and designation to include working temperatures and
pressures.  A diagram or picture would be helpful.
The ship was originally called SS France and was built by Chantiers de
L'Atlantique in St Nazaire, France.
I am a ship's engineer interested in the construction details of the
boiler as I wish to understand how the recent accident which claimed
seven lives may be prevented on other ships.

Hello shipengineer,

I was having an ICQ discussion with my father (retired naval engineer
with 30+ years service) regarding your question.  Here are some
extracts:

These are his comment:
"Boilers would have been built by the ship builders.  They will be
some sort of water drum (probably two) at the bottom and a steam drum
at the top. The steam would be generated in tubes between these (lots
of them!).  Usual causes of serious accidents are tube (s) bursting
(various reasons), furnace explosion (only likely whilst lighting up),
a pressure part failing (main pipe or boiler fitting), or a serious
fire from a fuel leak.  That's about it!"

"Sounds like a boiler explosion then. Only cause that I know is
incorrect purging before lighting.  Before lighting the boiler it
should be blown through with lots of air ti get rid of any potential
explosive mixtures of fuel/ air which can accumulate in the furnace
whilst shut down, or the lighting up was very late and too much
atomised fuel got into the boiler before the fire was established."

" It's the raising of steam pressure and warming the propulsion
machinery through that takes hours. If starting from cold about twelve
hours is probably the best time.  If one of the boilers had been kept
going (for auxiliary power) then four to six hours.
Sounds like they were late getting the last boiler(s) on and blew it
up!"
"Affects diesel burning ships more than heavy oil burners, and
particularly those that are steam atomised. Diesel evaporates easier
than heavy oil causing the explosive mixture more easily. Steam
atomisation makes this even worse because it is designed to atomise
the fuel anyway!!"

"Sounds like the boiler design was pretty conventional. Working from
inside out:  Furnace, surrounded by water tubes, an insulated gas
casing (to keep the hot gasses in the right place and the whole lot
surrounded by an air casing, usually about 18 inches from the gas
casing.  Air for combustion is blown into the space between the two
casings where it takes away the waste heat before entering the furnace
as combustion air.  The air in this space between the casings is at
several inches of water gauge pressure above atmospheric. This avoids
having a pressurised boiler room and allows better control of air into
the boiler.
The boiler will have been built by the shipbuilder."

If the boilers were made by the ship builders Chantiers de
l'Atlantique, you might want to contact them:

LES CHANTIERS DE L'ATLANTIQUE - PORT DE SAINT-NAZAIRE 
Base Sous-Marine - Ville -Port
Bd de la Légion d'Honneur - BP 173
44600 SAINT-NAZAIRE 
E-mail : contact@saint-nazaire-tourisme.com

http://www.chantiersatlantique.com/

Best regards, and good luck

THX1138

I agree with THX1138's comments above.  Interestingly, when the ship
was modified by NCL all the steam auxilliaries were removed and diesel
generators added.  It was then no longer necessary to keep the main
boilers running in port.  The last stam ship I worked on had
turbo-alternators and turbo feed-pumps (Coffin pumps, well known to
the US Navy!) so there was always at least one boiler in line and
normally two.

from "Power of the Great Liners" by Denis Grifiths:
p194-195
...Two bolier rooms easch contained four Penhoet (the ship's
builder)water tube boilers, all capable of 90 tons of steam per hour
generated at 915 psi and 930 degrees F. A de-superheater in the main
steam drum of each boiler allowed saturated steam to be produced for
assorted engine room auxilliaries and via afurther reducing valve,
hotel services. Total HP was 160,000  (40k per shaft)
She reached 33.8 knots on trials. Only required 131,000Hp for constant
29 knots cruising speed. Power transferred from turbines to props by
single-reduction gearing.

I would like to comment on the discussion you had, I was onboard the
norway on the day of the horrific explosion. I was an Navigator
trainee.
the boilers were cooling down at the time of the explosion, we had
just finished the 7 day roundtrip. i don´t know for sure wether we had
2 or 3 boilers running at the time, but i seem to remember that it was
3.
Also another thing you should be aware of, is that no steam was
released, the explosion was caused by fumes, (gas). Otherwise the
damages would have been more extensive, not to mention that we would
have seen the steam, and not just black smoke. This was the general
opinion onboard, but we still have to wait for the results of the NTSB
investigation.
As for the manufacturer, make and model of the boilers I cannot answer
with absolutism, but they were probably made from an independent
French company.
I would also liketo say that the events that took place that day was
the worst I´ve ever been through, and I agree with the engineer that
raised this discussion that this must never happen again. the death
toll now is 8.
I would also like to mention that I do not represent the cruise line
in this discussion, i came across it while I was searching through the
internet, this is just my personal experience and comments, which I
have also shared with the NTSB. More information can be obtained at
www.ncl.com or www.ss-norway.com
Also check out NTSB´s website.
I hope that I could clarify some of the questions raised.