Propulsion on Great Lakes vessels
James W. Hebert
I believe that the majority of Great Lakes vessels--lakers--
are powered by steam engines, as opposed to large, slow
RPM diesels more common on foreign vessels (salties).
I don't have any first hand experience with this, but from
some reading I have done I know that a steam engine would
prefer to use extremely pure water, and that in the case of
ocean vessels, the fresh water of the steam plant is contained
in a closed loop and recirculated.
After the power has been extracted from the steam, it is
condensed back to water in a condenser, where the steam
is cooled with raw water (salt water in the ocean going
case).
Is this same system used in fresh water vessels like lakers?
Since they are sitting in a rather large lake of fresh water,
I wonder if they used a closed loop system, or just pump
new fresh water aboard for steam instead of condensing out
the exhaust steam to water.
--jim
Jim Hebert, K8SS | Virtual Cruise of Lake Huron's
Beverly Hills, Michigan | NORTH CHANNEL
ji...@w8hd.org | http://tango.w8hd.org
Robert M. Martel
James W. Hebert (ji...@w8hd.org) wrote:
: I believe that the majority of Great Lakes vessels--lakers--
: are powered by steam engines, as opposed to large, slow
: RPM diesels more common on foreign vessels (salties).
I think it is the other way around - the majority of the
"lakers" operating have diesel engines with a minority still
"steamers" a quick count (subject to error) I come up with:
35 Diesel
26 Steam
(Actually more "steamers" than I expected.)
...
: Since they are sitting in a rather large lake of fresh water,
: I wonder if they used a closed loop system, or just pump
: new fresh water aboard for steam instead of condensing out
: the exhaust steam to water.
They have closed-loop systems - they cool with lake water, and
can "make" boiler make-up water with on-board distillation plants, but would
not actually circulate lake water - it may be fresh, but there is still
far too much junk in the water: would make for a short life-span on one's
boiler or turbines. Ask any Great Lakes engineer what sort of junk
they clean out of the strainers, just don't ask before lunch.
-Bob
--
******************************************************************************
Bob Martel - System Administrator | I met someone who looks a lot like you
Levin College of Urban Affairs | She does the things you do
Cleveland State University | But she is an IBM
(216) 687-2214 |
b...@meeker.csuohio.edu | -Jeff Lynne
******************************************************************************
Duane Burleson
> -Bob
And wouldn't the closed loop system save an incredible amount of
energy anyhow, why boil cold water to make steam when warm/hot water
could be made available?
duane
remove the .nospam to e-mail me
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Bill Williston
Hello James, the type of propulsion depends upon when a vessel was built,
'new' lakers, those built over the last 20 years are diesel. they're
ceaper to install and require less labor to operate than steam.
James W. Hebert <ji...@w8hd.org> wrote in article
<jimh-28049...@hotel.w8hd.org>...
> I believe that the majority of Great Lakes vessels--lakers--
> are powered by steam engines, as opposed to large, slow
> RPM diesels more common on foreign vessels (salties).
>
> I don't have any first hand experience with this, but from
> some reading I have done I know that a steam engine would
> prefer to use extremely pure water, and that in the case of
> ocean vessels, the fresh water of the steam plant is contained
> in a closed loop and recirculated.
>
> After the power has been extracted from the steam, it is
> condensed back to water in a condenser, where the steam
> is cooled with raw water (salt water in the ocean going
> case).
>
> Is this same system used in fresh water vessels like lakers?
Yes, but Lakers would, generally, have less horsepower than salties.
>
> Since they are sitting in a rather large lake of fresh water,
> I wonder if they used a closed loop system, or just pump
> new fresh water aboard for steam instead of condensing out
> the exhaust steam to water.
>
Jody L. Aho
Duane Burleson wrote:
>
> b...@meeker.csuohio.edu (Robert M. Martel) wrote:
>
> >James W. Hebert (ji...@w8hd.org) wrote:
> >: are powered by steam engines, as opposed to large, slow
> >: RPM diesels more common on foreign vessels (salties).
>
> >"lakers" operating have diesel engines with a minority still
> >"steamers" a quick count (subject to error) I come up with:
>
> > 35 Diesel
> > 26 Steam
> >
> > (Actually more "steamers" than I expected.)
> >...
>
> >: I wonder if they used a closed loop system, or just pump
> >: new fresh water aboard for steam instead of condensing out
> >: the exhaust steam to water.
>
> >can "make" boiler make-up water with on-board distillation plants, but would
> >not actually circulate lake water - it may be fresh, but there is still
> >far too much junk in the water: would make for a short life-span on one's
> >boiler or turbines. Ask any Great Lakes engineer what sort of junk
> >they clean out of the strainers, just don't ask before lunch.
>
> > -Bob
When you count the Canadian vessels, approximately 75% of the Great
Lakes fleet, including every vessel which entered service after 1967, is
Diesel powered.
The Diesel has a practical advantage over a steam turbine plant for
Great Lakes use in that the Diesel can change speeds fairly quickly,
whereas a turbine is best suited to run at high speeds for long
periods. In the Great Lakes, since a lot of navigating takes place in
confined water, and some vessels (especially the smaller self-unloaders)
make port every other day or less, the Diesel-powered boat is better.
Although close to maximum speed can be attained quickly, it takes the
turbine several hours to reach the full speed. Care also has to be
taken in slowing down a turbine powered boat gradually; a Diesel-powered
boat can stop relatively quickly.
The turbine does have the advantage over the Diesel plant in
reliability, though.
Although a few turbo-electric plants were in service on the Great Lakes
in the 1920s, the steam turbine era on the Great Lakes began in earnest
60 years ago on May 21, when the John Hulst entered service for the
Pittsburgh Steamship Company. This 612-foot iron ore carrier had a 2000
horsepower plant with two coal-fired water tube boilers, and she
developed approximately 11.5 statute miles per hour under full load.
Sister ships entered service later in the year on the Great Lakes
included the Governor Miller, the William A. Irvin (open for tours in
Duluth), and the Ralph H. Watson. Most vessels built between this group
in 1938 until the Canadian Leader, the last turbine-powered Great Lakes
vessel, entered service October 12, 1967, were steam turbine powered.
Jody Aho
ja...@cp.duluth.mn.us
http://www.cp.duluth.mn.us/~jaho
Author, "The Steamer William A. Irvin: Queen of the Silver Stackers"
Frank
Jody L. Aho wrote:
> (snip)
>
> When you count the Canadian vessels, approximately 75% of the Great
> Lakes fleet, including every vessel which entered service after 1967, is
> Diesel powered.
>
> The Diesel has a practical advantage over a steam turbine plant for
> Great Lakes use in that the Diesel can change speeds fairly quickly,
> whereas a turbine is best suited to run at high speeds for long
> periods. In the Great Lakes, since a lot of navigating takes place in
> confined water, and some vessels (especially the smaller self-unloaders)
> make port every other day or less, the Diesel-powered boat is better.
> Although close to maximum speed can be attained quickly, it takes the
> turbine several hours to reach the full speed. Care also has to be
> taken in slowing down a turbine powered boat gradually; a Diesel-powered
> boat can stop relatively quickly.
>
> Jody Aho
> ja...@cp.duluth.mn.us
> http://www.cp.duluth.mn.us/~jaho
> Author, "The Steamer William A. Irvin: Queen of the Silver Stackers"
>
A ex-yooper jumps in......
Every summer for the Portland, Oregon Rose Festival some ships are
brought in and tied up at the sea-wall downtown.
They usually have a group of WWII Canadian mine sweepers which are now
used as training vessels. They have wooden hulls to avoid magnetic
mines,and have been restored.
Last summer the Canadians brought a Missle cruiser in. In my visit of
the Bridge we were told the ship was powered by turbine engines, the
same as on a 747 aircraft. They could not state the top speed of the
ship, but said that in an emergency, it was capable of being stopped
within it's length.
Seems to me gas turbine engines would be the least maintenance, and are
ready to go to work upon startup.
I have seen foreign Grain Ships and freighters come up the river that
were using gas turbine power. You can hear the high pitched whine of
them.
Why don't more Great Lakes vessels use that type power?
--
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Don Stauffer
Duane Burleson wrote:
>
> b...@meeker.csuohio.edu (Robert M. Martel) wrote:
>
> >James W. Hebert (ji...@w8hd.org) wrote:
> >: I believe that the majority of Great Lakes vessels--lakers--
> >: are powered by steam engines, as opposed to large, slow
> >: RPM diesels more common on foreign vessels (salties).
>
> > I think it is the other way around - the majority of the
> >"lakers" operating have diesel engines with a minority still
> >"steamers" a quick count (subject to error) I come up with:
>
> > 35 Diesel
> > 26 Steam
> >
> > (Actually more "steamers" than I expected.)
> >...
>
> >: Since they are sitting in a rather large lake of fresh water,
> >: I wonder if they used a closed loop system, or just pump
> >: new fresh water aboard for steam instead of condensing out
> >: the exhaust steam to water.
>
> > They have closed-loop systems - they cool with lake water, and
> >can "make" boiler make-up water with on-board distillation plants, but would
> >not actually circulate lake water - it may be fresh, but there is still
> >far too much junk in the water: would make for a short life-span on one's
> >boiler or turbines. Ask any Great Lakes engineer what sort of junk
> >they clean out of the strainers, just don't ask before lunch.
>
> > -Bob
>
> >******************************************************************************
> > Bob Martel - System Administrator | I met someone who looks a lot like you
> > Levin College of Urban Affairs | She does the things you do
> > Cleveland State University | But she is an IBM
> > (216) 687-2214 |
> > b...@meeker.csuohio.edu | -Jeff Lynne
> >******************************************************************************
>
> And wouldn't the closed loop system save an incredible amount of
> energy anyhow, why boil cold water to make steam when warm/hot water
> could be made available?
>
> duane
> remove the .nospam to e-mail me
> burl...@rust.net
>
> ---- VISIT MY WILDLIFE AND TRAVEL PAGE ----
>
> >>> MY NEW PAGE IS NOW AVAILABLE <<<
> >>> North Cascades and Olympic National Parks <<<
> >>> at http://www.rust.net/~burleson/washington.html <<<
>
> --- Images of Yellowstone, Grand Tetons, Michigan ---
> ---and the Everglades at http://www.rust.net/~burleson---
No, actually not. The efficiency of a steam engine is related to the
difference between the temperatures of the inlet steam and the outflow
steam/water. If you do not cool the steam/hot water well enough with a
heat exchanger/radiator the efficiency will suffer. You can do more
work per unit time with a steam engine exhausting into a cold condensor
than into a hot one.
So even on closed loop systems, the heat exchanger should cool the
exhaust to as cool a temperature as possible.
--
Don Stauffer in Minneapolis
home web site- http://home1.gte.net/stauffer/
home email- stau...@gte.net
work email- stau...@htc.honeywell.com
Hhilbrink
>Subject: Re: Propulsion on Great Lakes vessels
>From: "Jody L. Aho"
>The Diesel has a practical advantage over a steam turbine plant for
>Great Lakes use in that the Diesel can change speeds fairly quickly,
>whereas a turbine is best suited to run at high speeds for long
>periods.
My two cents worth.
About 1933 the Bureau of Ships decided on steam turbine propulsion for naval
vessels. This created an infrastructure for the manufacture of steam turbines.
It proved to be a classis error, because the US did not have the capacity in
WW2 to built anything other than steam turbine plants and 1900's design triple
expansion steam engines. The Victory class WW2 freighters took advantage of
the turbine's power and had a top surface speed of 22 knots, just enough to
outrun fastest U-Boat. The flip side is that the Liberty class ships were
equipped with a triple expansion steam engine giving this thing a top speed of
9 knots, sitting ducks.
The steam turbine persisted in the US until the 1960's, while the Europeans
were powering ocean going ships with diesels since the early 1930's
To this day there is no large diesel manufacturer in the US. The 20.000 HP
class are made by Mitsubishi, Burmeister und Wien, and, of all places, by
Sulzer in Switserland.
Modern diesel plants are completely automated, controlled from the bridge, and
only need an engineer in a watch capacity. Acquisition cost and operating fuel
plus manning costs, are lower for a diesel than a steam turbine. That's why
modern lakers, max 15 knots or so, have diesels
Hans.
James Zeirke
As far as diesels go, what is the most common brand of diesel engine?
The Pielstick??
--
Jim Zeirke
Firefighter/Chaplain
Local 407, Intl. Assn. of Fire Fighters
Member--Federation of Fire Chaplains
1Thessalonians 3:11-13
James W. Hebert
In article <199804291404...@ladder03.news.aol.com>,
hhil...@aol.com (Hhilbrink) wrote:
[talking about steam vs diesel power for ships]
> About 1933 the Bureau of Ships decided on steam turbine propulsion for naval
> vessels. This created an infrastructure for the manufacture of steam
turbines.
> It proved to be a classis error....
> To this day there is no large diesel manufacturer in the US. The 20.000 HP
> class are made by Mitsubishi, Burmeister und Wien, and, of all places, by
> Sulzer in Switserland.
>
> Modern diesel plants are completely automated, controlled from the bridge, and
> only need an engineer in a watch capacity. Acquisition cost and
operating fuel
> plus manning costs, are lower for a diesel than a steam turbine. That's why
> modern lakers, max 15 knots or so, have diesels
Perhaps the same people at the Bureau of Ships were editors of the
science textbook I recall as a boy. I distinctly remember that
my 7th Grade Science class used a textbook which stated
as a matter of fact that "internal combustion engines" could
not be built larger than approximately 3,000 HP. I asked the
teacher why there was such a limit, and he hypothesized that
mechanical inefficiencies and frictions would aggregate as the
engine became larger, or something like that.
(Oh, that 7th Grade class was not as long ago as some might think.
It would have been around 1962.)
In railroad locomotives, the province of large diesels in the U.S.,
there did seem to be a limit of around 3,000 HP for quite a while,
although now there are larger engines in use.
I think EMD (ElectroMotive Division of GM) is making a 20 cyclinder
engine with about 8,000 HP that they market to marine applications.
There were some large river tow boats built recently with engines
of this size.
But diesels in the 20,000 HP range! That is a big engine!
William Lafferty
Hhilbrink <hhil...@aol.com> wrote in article
<199804291404...@ladder03.news.aol.com>...
> It proved to be a classis error, because the US did not have the
capacity in
> WW2 to built anything other than steam turbine plants and 1900's design
triple
> expansion steam engines.
This is hardly true: The United States had a number of manufacturers of
relatively large Diesel marine engines, including Winton, Fairbanks Morse,
McIntosh & Seymour, Worthington, Coooper-Bessemer, and others before
World War II, and whose plants were moblized to provide the motive power
for a wide variety of vessels, especially landing craft, submarines, tugs,
tankers, and
freighters. By war's end, for example, Milwaukee's Nordberg Manufacturing
was producing a class of large 6-cylinder Diesel that propelled a huge
number of C1 freighters, some of which are still functioning today.
> The steam turbine persisted in the US until the 1960's, while the
Europeans
> were powering ocean going ships with diesels since the early 1930's
Actually, European owners, especially in Scandinavia, began using
Diesel propulsion for ocean-going vessels since before World War I.
Denmark's East Asiatic Company being a pioneer. However, the
first Diesel-powered vessel to cross the Atlantic was the Canadian
Great Lakes freighter *Toiler* (later *Mapleheath*) in 1910, built by
Swan, Hunter & Wigham Richardson with a diminutive Polar two-cycle
Diesel, ironic considering what would be the Lakes' enduring
resistance to Diesel power.
> To this day there is no large diesel manufacturer in the US. The 20.000
HP
> class are made by Mitsubishi, Burmeister und Wien, and, of all places, by
> Sulzer in Switserland.
This would come as a surprise to the folks at General Motors and
Caterpillar, I imagine. Although not in the 20,000 hp range,
several 1000-foot lakers are powered by four EMD 645-E7s, that's
eighty cylinders producing almost 15,000 hp. I call that a large
Diesel installation, if not, separately, a particularly large engine
(at 3600 bhp). Burmeister & Wain pioneered Diesels for deepwater
before World War I with their four-cycle, 8-cylinder, 900 shp engine
of 1912.
William Lafferty
Robert M. Martel
Hhilbrink (hhil...@aol.com) wrote:
...
: Modern diesel plants are completely automated, controlled from the bridge, and
: only need an engineer in a watch capacity. Acquisition cost and operating fuel
: plus manning costs, are lower for a diesel than a steam turbine. That's why
: modern lakers, max 15 knots or so, have diesels
From the reading I've done the primary reason cited for the installation
of diesel engines over steam has to do with initial costs. The steam plant
costs more to purchase, but the diesel costs more over the life of the vessel.
Given the usual longevity of great lakes vessel's sevice lives the cost
over time does matter.
Cleveland-Cliffs proposed 1000-footer was to be steam powered - Cliffs
stated that the steam plant would cost more up-front, but expected to more than
make-up for that cost over the life of the vessel. Few, if any, companies
look beyond the next quarterly report these days.
Diesel engines are torn down and rebuilt evry winter on great lakes
vessels. Steam plants, if properly shutdown, do require such intensive
work on an annual basis.
Steam plants are no strangers to automated controls - vessels were
running without a fireman to watch the boiler as far back as 1964.
Most of these books (and stories by those involved in great lakes
shipping) are several years old. How much things have changed I can't say -
I'm sure there is not the "infrastructure" to supply steam powerplants for
ships that there once was.
-Bob Martel
Bob Thompson
Does Sulzer actually manufacture many of the large diesel engines any
more, in Switzerland or elsewhere? I thought the vast majority of
Sulzer engines were produced under license by manufacturers in Korea,
Japan, Finland, etc.
On 29 Apr 1998 14:04:44 GMT, hhil...@aol.com (Hhilbrink) wrote:
>
>The 20.000 HP
>class are made by Mitsubishi, Burmeister und Wien, and, of all places, by
>Sulzer in Switserland.
>
>Hans.
Deayton
>Why don't more Great Lakes vessels use that type power?
Probably because the machinery costs too much, and they would be overpowered
for the conditions they would sail in.
Alistair Deayton
Paisley, Scotland
Robert Polvi
Ah, be still my beating heart, a subject I am a wee bit
familiar with. Having just received my latest copy of Marine Log
yesterday I see on page 16 of the April edition that Wartsila NSD
is developing a DIESEL of 65,880KW (89,640 bhp)In the same article
the most powerful current Diesel is a MAN B&W 12 cylinder of
55,000Kw (75,000). These monsters are used to power 6000+TEU
Container ships.
By chance in the same magazine is a report of the GE LM6000
that offers over 40,000Kw (50,000bhp). Now it has to be recognised
that all of these BIG BOYS are too too much for the lakes but it
does give a good example of how powerful prime movers can be today.
For what its worth a picture of a Sulzer 11RTA96C crank-shaft is shown being assembled. 7 men are standing on the bed plate and the crank
looks about 50feet long with 4 to 5 foot throws.
Bob The Stoker
Gary Curtis
William Lafferty wrote:
> This is hardly true: The United States had a number of manufacturers of
> relatively large Diesel marine engines, including Winton, Fairbanks Morse,
> McIntosh & Seymour, Worthington, Coooper-Bessemer, and others before
> World War II, and whose plants were moblized to provide the motive power
> for a wide variety of vessels, especially landing craft, submarines, tugs,
> tankers, and
> freighters. By war's end, for example, Milwaukee's Nordberg Manufacturing
> was producing a class of large 6-cylinder Diesel that propelled a huge
> number of C1 freighters, some of which are still functioning today.
>
>
I hope that I remember correctly, since I can't find it in any of my references.Is
this the same Nordberg Manufacturing that built the Quincy Hoist in the
early 1920s?
gary curtis
Jeffrey Birch
Okay...gotta weigh in on this one!
Effeciency...it is all on how your measure it. Turbines are more
efficient exhausting to a cold condenser, true, but the cold condensate
that results must be reheated to main steam temperature for reuse. The
only economically important measure of effeciency is how much fuel you
burn, and for the hoursepower we use on the lakes, diesels win that one.
Operability...A completely diesel engineroom (main propulsion and
electrical generation) allows relatively easy start-up and shutdown of
engines, allowing reduction of fuel consumption when the associated
machine is not needed. Turbines require a complex and lengthly procedure
to start-up, requiring that they be left running if possible, from a
practicality standpoint.
The first commercial diesel powered vessel of large size was the MV
HENRY FORD II, if I remember my Greenwood. She was built in the 20's and
retained her original diesel propulsion to the end.
Steam enginerooms require a large number of auxiliary systems to
operate, and thus consume energy just sitting there.
Turbines are VERY responsive to changes in throttle settings, and will
"spool up" rapidly. It is the ability of the boilers to deliver the
suddenly increased steam demand that is the limiting factor.
The primary disadvantage of turbo-electric drive systems is weight, and
a reduction in efficiency during the second energy conversion
(Steam->rotation->electrical->rotation)
There...my speen is vented.
Jeff
Honolulu
James W. Hebert wrote:
> I believe that the majority of Great Lakes vessels--lakers--
> are powered by steam engines, as opposed to large, slow
> RPM diesels more common on foreign vessels (salties).
>
> I don't have any first hand experience with this, but from
> some reading I have done I know that a steam engine would
> prefer to use extremely pure water, and that in the case of
> ocean vessels, the fresh water of the steam plant is contained
> in a closed loop and recirculated.
>
> After the power has been extracted from the steam, it is
> condensed back to water in a condenser, where the steam
> is cooled with raw water (salt water in the ocean going
> case).
>
> Is this same system used in fresh water vessels like lakers?
>
> Since they are sitting in a rather large lake of fresh water,
> I wonder if they used a closed loop system, or just pump
> new fresh water aboard for steam instead of condensing out
> the exhaust steam to water.
>
> --jim
>
> Jim Hebert, K8SS | Virtual Cruise of Lake Huron's
> Beverly Hills, Michigan | NORTH CHANNEL
> ji...@w8hd.org | http://tango.w8hd.org
--
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james fahlstedt
As far as US flag lakers go, it appears to be the EMD 645 locomotive
diesel. This is a very simple two stroke diesel which is easy to
maintain and so common that parts are easy to find.
Bruce Burden
Frank (fma...@europa.com) wrote:
:
: Seems to me gas turbine engines would be the least maintenance, and are
: ready to go to work upon startup.
:
Pretty much true. However, few vessels need the acceleration
offered by gas turbines.
:
: were using gas turbine power. You can hear the high pitched whine of
: them.
:
Hmmm. Are you sure that was a gas turbine whine, or cooling
fans? You are closer, of course ;-) My experience with salties
and lakers are that you can hear the throb throb of the diesels,
particularly out by Whitefish Point.
:
: Why don't more Great Lakes vessels use that type power?
:
Gas turbines use about 80% of the fuel at idle that they
do at full throttle. For a boat that must navigate congested
shipping lanes (Detroit River) and harbors, this is a very
expensive option in terms of fuel consumed.
Bruce
--
------------------------------------------------------------------------
"I like bad!" Bruce Burden Austin, TX.
- Thuganlitha
The Power and the Prophet
Robert Don Hughes
Bruce Burden
Hhilbrink (hhil...@aol.com) wrote:
: About 1933 the Bureau of Ships decided on steam turbine propulsion for naval
: vessels. This created an infrastructure for the manufacture of steam turbines.
: It proved to be a classis error,
:
An error? Hmmmm. Well, in 1927 the US Navy constructed two
aircraft carriers, the USS Saratoga and USS Lexington. They used
turbo-electric propulsion. They produced 180,000 SHP, with a
plant weight of 6,335 tons, or a density of 78.3 lbs/hp. In the
mid/late 30's, the US Navy built the North Carolina class of
treaty battleship. It featured 121,000 SHP, utilizing double-
reduction, high speed/pressure steam boilers/turbines. It had
a plant weight of 3,286 tons, or a density of 60.83 lbs/hp. As
a side note, the USS North Carolina was attached to the British
Navy's Home Fleet to help bolster their strength. The Brits
hated this ship, as they were still using slow speed/pressure
boilers/turbines. The USS North Carolina has an endurance of
13,500 miles @ 15 knots, or about double what the Brits could
manage. Result - the USS North Carolina only refueled about
1/2 the times the British Home Fleet did. It also had an endurance
of 3,456 miles @ 27 knots.
The last battleships in service, the US Navy Iowa class
ships, featured 212,000 SHP. Quite beyond diesels of the time.
I think the Japanese would agree that the BoS decision to
use high temp/pressure/speed boilers/turbines was NOT a "classic
error"!
:
: The steam turbine persisted in the US until the 1960's, while the Europeans
:
Actually, until about 1995, when the last battleships were
formally stricken from the US Navy fleet. :-)
:
: plus manning costs, are lower for a diesel than a steam turbine. That's why
: modern lakers, max 15 knots or so, have diesels
:
Absolutely! However, 15 knots seems about the practical limit
for diesels. They quickly lose efficiency when required to
operate at speeds above 15 knots. That is why the US Navy
played with CODAG vessels - COmbined Diesel And Gas. These ships
(frigates as I recall) had diesels for normal cruise duties,
and a gas turbine was fired to provide top rated speed.
However, for a commercial vessel, there is little call
for 15+ knots - fuel costs quickly mount above 15 knots. Remember,
to double the speed, you square the HP requirements, all things
being equal.
BILLYVIC
I sailed for US Steel in the 70s aboard the T. W. Robinson. She was the first
turbo-electric vessel manufactured for the lakes. She started service in 1925
and i believe she was retired around 1982.
The M. V. Myron C. Taylor was equipped with a 4000 shp V-16 Nordberg diesel.
Each bank of cylinders had it's own turbocharger about the size of a VW Bug.
The pistons in this engine were about 14 inches in diameter and about 20 inches
tall. The piston, wrist pin and rings assembly weighed 310 pounds each. The
M. V. Calcite II had a 3500 shp V-10 Cat engine.
BILLYVIC
Jeff, well stated.
rkth...@mail.cqr.wiscnet.net
> Last summer the Canadians brought a Missle cruiser in. In my visit of
> the Bridge we were told the ship was powered by turbine engines, the
> same as on a 747 aircraft.
The Gas Generator portion of the engine is derived from an aircraft engine,
in many cases. The Power Turbine is a frewheeling device attached to the
outlet of the Gas Generator; this is what is actually coupled to the gearbox.
> I have seen foreign Grain Ships and freighters come up the river that
> were using gas turbine power. You can hear the high pitched whine of
> them.
The whine you heard was the turbochargers on the big diesel engines...
> Why don't more Great Lakes vessels use that type power?
Gas turbines are very, very thirsty.
> --
> * Frank Maskus 8832 N Syracuse #716 Portland, Oregon 97203 *
R.K. Thompson
Spam-blocking: remove
"cqr" from e-mail address
David Scott
James W. Hebert wrote:
> I believe that the majority of Great Lakes vessels--lakers--
> are powered by steam engines, as opposed to large, slow
> RPM diesels more common on foreign vessels (salties).
>
> I don't have any first hand experience with this, but from
> some reading I have done I know that a steam engine would
> prefer to use extremely pure water, and that in the case of
> ocean vessels, the fresh water of the steam plant is contained
> in a closed loop and recirculated.
>
> After the power has been extracted from the steam, it is
> condensed back to water in a condenser, where the steam
> is cooled with raw water (salt water in the ocean going
> case).
>
> Is this same system used in fresh water vessels like lakers?
>
> Since they are sitting in a rather large lake of fresh water,
> I wonder if they used a closed loop system, or just pump
> new fresh water aboard for steam instead of condensing out
> the exhaust steam to water.
>
> --jim
>
> Jim Hebert, K8SS | Virtual Cruise of Lake Huron's
> Beverly Hills, Michigan | NORTH CHANNEL
> ji...@w8hd.org | http://tango.w8hd.org
The steam propulsion systems are being phased out in favour of the large
low R.P.M. diesel engines. Economics is the rule and diesels are cheaper
to operate. The newer diesels even use a mix of diesel and bunker c oil
(heavy black oil) when on the open lakes, as the mixture tends to smoke
at lower operating ranges. The diesel also has the advantage of being
operated from the bridge, so fewer people are required to run the
vessel. Variable pitch propellers are the norm on these vessels and they
tend to operate the engine at a constant R.P.M. for further savings. I
believe the usual top speed is now 14 knots. As to the Steam engines,
you're right about them needing clean water. The water in the boilers is
not directly from the lakes as it contains minerals and salts. The lake
water is "boiled" in an Evaporator and the steam is condensed to pure
water. Build up in the Evaporator is disposed of back into the lake.
Closed loop systems are required as it takes time to build an
inventory of pure water. Most ships have holding tanks inside the hull
around/below the engine room area. The water is pumped into the boilers,
to create steam, the steam then going into superheaters (to ensure it is
very dry, my experience puts temperature around 500 F at 700 psi) before
going into the turbine(s). The steam going through the turbine causes it
to spin and the spin is directed through a gearbox to the prop. The
steam, having lost most of it's heat and pressure then enters the
Condenser below it, and is converted back to water, and pumped back into
the holding tanks.
Some systems use a single turbine, others have a high pressure and a
low pressure turbine set. Going even further back the original steam
engines were of the Triple Expansion Type - similar to an internal
combustion/diesel only steam was used. The same closed loop system was
required.
Hope this isn't too wordy for everyone.