by MEC407
Thanks to the help of Mr. Steve Palmano, I am pleased to post this voluminous discussion about the history of the GE FDL engine. This discussion took place on the "old" railroad.net site. Unfortunately, many excellent discussions on that site were lost when the "new" site was launched. Mr. Palmano had the foresight to keep an archival copy of the FDL discussion, which I will post here for all to read and enjoy. And, of course, if you have any information to add, please feel free.
I have left the original discussion 99.9% intact, except for removing users’ e-mail addresses, and inserting line breaks for easier reading.
FDL Origins
Posted by Allen Hazen (a.hazen@-) on Thu, Sep 7, 00 at
21:49
I have been curious about the origins of the FDL engine. Here is a precis of
what I know so far. I post it for the benefit of the curious... and in hopes
of stimulating the knowledgeable into telling me more!
(i) The engine used, starting in the mid 1940s, on the GE 70-tonner (and on
some similarly sized locomotives built by other builders) was an ancestor, the
Cooper-Bessemer "FWL" (or "FWL-T"). Same cylinder dimensions, and I don't know
how much further resemblance (power assembly construction?). Six cylinder,
in-line, lower per-cylinder power rating than the contemporary Alco 244 engine
used on contemporary full-size Alco-GE diesel locomotives.
(ii) A V-configuration version was developed NO LATER THAN 1952: a 12-cylinder
version was used in the locomotives GE built for Queensland (Australia)
Railways in 1952. This was called the "FVL," but had the low output/cylinder
of the first 70-tonners.
(iii) An uprated version-- equal in power/cylinder to the mid-1950s version of
the Alco 244-- existed by 1954, when it was used in the four-unit "Rolling
Laboratory," the GE test locomotive (#750) operated mainly on the Erie
Railroad. GE, which eventually (WHEN?) bought the design and manufactured the
engine themselves, calls this the "FDL".
(iv) I asked on a Naval History web discussion board to see if this had been
used by the U.S. Navy. It was. A class of mid-1950s landing ships ("LST", but
about twice the size of a WW II LST) was powered by six 2400 hp
Cooper-Bessemer "FVAM" engines per ship. (The person who mentioned them called
them the "Suffolk County" class, but Suffolk County was not the first in the
series-- there were about ten ships in the class, so something like 60
sixteen-cylinder C-B engines closely related to the FDL were in U.S. Navy
service before the first FDL-16 was installed in the U25B prototype.)
(v) Is there a system to the model designations? At a guess, "F" is the basic
design, "V" is probably for V-configuration, and-- in Cooper-Bessemer usage--
the final "M" or "L" denotes versions for Marine or Locomotive application.
I'm betting that the "A" in FVAM was for the increased power rating, and that
the engines installed in GE 750 would have been called "FVAL" by C-B at the
time. Was "FDL" ("DL" for Diesel Locomotive) a GE designation, introduced
after they bought the design and applied retroactively to the FVAL engines
used in early U-series locomotives?
(vi) And, as if we needed more evidence that railroad duty is harder on diesel
engines than marine-- note that the U.S. Navy's experience with the FVAM-16
wasn't enough to give the U25B a fully debugged and trouble-free engine.
(I'm afraid I haven't said much here that isn't common knowledge. Sorry.)
Follow-Up Postings:
RE: FDL Origins
Posted by: Michael Schaefer (mbschaefer@-) on Fri, Sep 15, 00 at 4:08
The main reason that marine duty is not as harsh is that the load dosent vary
nearly as much on ships as locomotives. locomotives go from idle to high load
and back every few seconds when switching and they take the shock of the train
slack as well, just try kick switching with out bracing your self in the seat,
and then realize that the loco has to do that all its life.
I will testify that locomotives are the toughest machines on the planet.
But then again Im not sharing any new info in this post.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Sat, Sep 16, 00
at 2:01
Thanks, Mike. It occurs to me that my naval history reading gave an example. A
book (forgotten the author but could find it if anyone wants) called "The
Arnheiter Affair," about the removal of a Lt. Commander Arnheiter from command
of a destroyer escort during the Viet Nam War. The ship was a WW II era ship
with Fairbanks Morse engines very similar to those used in FM locomotives
postwar. One episode reported was about the engineering officer's attempt to
explain to Arnheiter the restrictions on frequency of power change, etc, that
were necesseary to prolong the life of the diesel engines: the Navy can
tolerate operating restrictions that would leave a locomotive totally useless!
In addition, the engine-room of a ship may be a much cleaner and less
vibration-heavy environment than the hood of a locomotive.
RE: FDL Origins
Posted by: Michael Schaefer (mbschaefer@-) on Sat, Sep 16, 00 at 5:08
Absolutly true, even in rough seas a water vessel doesnt even suffer half the
abuse of a locomotive, the cleanliness comes from the fact that there is no
dirt out at sea, even the air is clean once your away from port.
On a locomotive you have nothing more than sheet metal with seams and vents
all over it, with ALCo and GE haveing pressureized car bodies(ALCo 1st), the
dirt still gets in and stays in unless the owner has realy good maintenance.
But its the constant speed and load changes, and the vibration/harmonic/stress
diferantals that cause the most problems in designing loco prime movers. The
severe shocks encountered in service dont help much, getting knocked out of
the seat once and a while makes me wonder how they handle it at all.
Mike.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Sat, Sep 16, 00
at 22:41
Thanks again. I knew that both the duty cycle and the dirty shaky environment
were hard on railroad diesels, but as a non-engineer and amateur, had no idea
which was more serious.
What, by the way, are you referring to in saying that Alco was first with
pressurized carbodies? I thought this was a feature of the U25B that Alco
didn't catch up to until the Century series introduced 3 years or so later.
Have I missed something?
RE: FDL Origins
Posted by: JR (jradtke@-) on Sun, Sep 17, 00 at 9:49
Actually Baldwin was the first builder to offer pressurized bodies. Roto-Clone
air filters were installed on a 15 unit order for the French North Africa RR
in the late forties - early fifties.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Sun, Sep 17, 00
at 21:50
Thank you, JR. Apparently EMD's E-8 and E-9 also had pressurized engine rooms.
Apparently GE (quite correctly) never claimed that the U25B was the FIRST
locomotive with a pressurized carbody, but they did emphasize the centralized
air system as a major innovation, and I thought the U25B was the first modern
hood unit to be pressurized, with EMD and Alco catching up with the GP30 and
the Century line.
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Wed, Sep 20, 00 at 18:31
Allen, here is some data obtained from various sources, with interpolations
and extrapolations, that might add a few more pieces to the FDL puzzle.
CB had established a relationship with GE in the 1930s, and when the FW series
engine was introduced circa 1945, GE locomotive applications were probably
envisaged as a big part of its potential market.
The 'F' in the designation seems to relate to cylinder size (i.e. E was
smaller, G was bigger) but I don't know the significance of the W. Neither do
I know what cylinder configurations the FW was originally available in.
As is well-known, GE first used the 6 cylinder model (FWL-6T) in both the
'domestic' (B-B) and 'export' (C+C) 70 tonner models. As far as I've been able
to trace, its first use of the 12 cylinder model (FVL-12T) was in the 75 tonne
(metric ton) meter gauge A1A-A1A shovel-nose units that went to General
Belgrano in Brazil circa 1949-50. Very similar 77 tonne units went to Chile
shortly afterwards, so the 1952 Queensland road switchers appear to be third
application for this engine.
Some time in the mid-1950s GE asked CB for more powerful engines, particularly
8 and 12 cylinder models, required for its new export model range. It seems
that CB was still GE's preferred supplier, but it may have been reluctant to
spend the development money without certainty of return. So there was a new
agreement, under which GE got its engines on a cost-plus basis, with the right
to undertake manufacture at some time in the future. Under this provision, GE
started assembling 16 cylinder engines circa 1962, using CB-supplied
components, although for a while longer (I don't know how much longer) CB
continued to supply completed 8 and 12 cylinder engines. I haven't been able
to determine when CB completely disengaged itself, and GE assumed total
responsibility for design, development and manufacture.
If one looks at the ratings, the FWL-6T as used in the 70 tonner was 660/600
hp, but as used in the export U9B/C of 1956/57 it was 990/900 hp, or 165/160
hp per cylinder. The same per cylinder ratings applied to the FVL-8T (8
cylinder) used in the export U12B/C(1320/1200 hp) and the FVL-12T (12
cylinder) export U18C (1980/1800 hp). The inference is that CB did whatever
re-engineering was required for the 50% increase in per-cylinder output.
Early FVL-12T applications were at strangely low per cylinder ratings. Local
ambient conditions, or rather derating for these might have explained this in
part, but maybe the early vee variants were not so robust? Perhaps that
unusual articulated rod design was a factor? As long as GE had easy access to
the Alco 12-244 for its more powerful export models, maybe it was prepared to
leave the FVL-12T as it was, or at least leave it to CB's discretion as to
what development work should have been undertaken. But its divorce from Alco
would have changed all of that.
The 8 cylinder export model was modestly uprated to 1420/1300 hp (as the
U13B/C) around 1961, still I believe with what was referred to as a CB engine.
However, the same increment was not applied to the 12 cylinder export model
(as the 2150/2000 hp U20C, with long chopped nose) until 1964, by which time
the engine was described as a GE 7FDL-12.
The next power output increments amongst the export models show up in the U15C
of around 1968 (FDL-8 at 1650/1500 hp) and then the U26C of 1971 (FDL-12 at
2750/2600 hp, alternator, short nose, and high-adhesion trucks).
From this I'd infer that the early GE-built FDLs were not a lot different to
the late CB FWL/FVL models, but that from the mid-1960s, GE was doing a lot of
re-engineering work to increase the specific output of the FDL, and making the
engine "its own".
Many years back I read a GE document that explained the significance of the
various elements of its 7FDL designation and how it fitted in with its general
component designation system, but I never thought to keep a copy. All I recall
now is that the 'L' did indicate locomotive, as one might expect.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Wed, Sep 20, 00
at 22:20
Steve Palmano--
THANK YOU!!!! VERY infomative! (The power ratings got discussed in the 244 and
241 engine strings on the Alco forum a few weeks ago. The C-B "E" engine you
refer to was on the low powered Monongahela Connecting centercab that was
mentioned.)
Perhaps you know the answers to the questions I asked in the "Factory
Questions" string on this forum: in particular, is the Grove City plant where
GE Transportation Systems makes its diesel engines the old C-B plant?
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Thu, Sep 21, 00 at 16:17
Allen, I can't really help you with your factory question. Perhaps like you,
I'm very much an 'outside observer' trying to make sense of information
fragments. Grove City was the original home of the 'Bessemer' part of
Cooper-Bessemer, whereas Cooper came from Mt. Vernon, Ohio. And I think that
for quite a while, Grove City was the main manufacturing point for
Cooper-Bessemer/Cooper Industries reciprocating engines and compressors. So
maybe a part of the plant was sold to GE. And the idea that GE manufactured
7FDL engines at Erie may have arisen during the period when it was assembling
the 16 cylinder models from CB-supplied components.
Here's something additional on the CB engine designations that I should have
looked at again and included in my previous post. (More haste, less speed!)
Evidently the uprated, i.e. 165/150 hp/cylinder, version of the CB FWL/FVL
engine was known as the 'B' series.
Some old South African Railways roster diagrams that I have show its 1958 U12B
fleet (31 class) to have CB FVBL-8 engines (at 1320/1200 hp) and its 1959
U18C1 fleet (32-000 class) to have CB FVBL-12 engines (at 1980/1800 hp).
(SAR's next GEs were its 33-000 class in 1965, low-nose U20C models with GE
7FDL-12 engines at 2150/2000 hp).
By way of a cross-check, Janes 1981-82 has some useful information on the
RFFSA Brazil diesel fleet. The 1958-59 GE U12Bs and U12Cs are shown as having
CB FVBL-8T engines at 1320 hp (gross), and the 1957 GE U9Bs as having CB FWB-6
engines at 990 hp (gross). The C+C 70 tonners (1947-56) are shown as having CB
FWL-6T engines at 660 hp (gross).
There are some differences here, in that the trailing'T' seems to be optional
- maybe it was dropped as being superfluous, as all of the 'B' engines were
turbocharged. And I wonder if the 'FWB-6' should not have been 'FWBL-6'?.
So, the apparent sequence is:
The 'original' versions of the CB 9x10.5 engine as used by GE were the FWL-6T,
at up to 660/600 hp, and the FVL-12T, at up to 1100 hp (net).
The uprated, or 'B' series CB engines, as used by GE in its export U-series
from late 1956, were the FWB(L)-6, FVBL-8, and FVBL-12, all at 165/150 hp per
cylinder. Of course, the 8 and 12 cylinder engines at this rating were
apparently first used in prototype #750. I can't trace any previous use of the
8 cylinder engine by GE, but it may have been used in two pre-U-series models
supplied to Manila Railways in the Philippines in 1956. (Both were Cape gauge
C-C models rated at 1200 hp (net), one being a cab unit (miniature of the
#750/NSW Class 43 concept) and the other combining a shovel-nose front-end
with a road-switcher long-hood body. So far I haven't been able to confirm the
engine type fitted to each.)
GE discontinued the 6 cylinder models around 1958-59 after selling only a
handful of U9B/Cs, so from its perspective at least, the 'V' and 'W'
characters were no longer needed - all engines were vee-form. Into the realm
of speculation, did the FVBL-8 and FVBL-12 metamorphose into the FDL-8 and
FDL-12, the 'V' being dropped and the 'D' representing another engineering
iteration - although then there's a missing 'C' iteration?
The RFFSA list in Janes 1981-82 also shows the 1963 U-13B fleet as having GE
7FDL-8 engines at 1420 hp (gross). However, according to Phil Wormald's GE
export site, 1420 hp U13C s were supplied to Gabon as early as 1960.
Ostensibly, this was when CB was still supplying the 8 cylinder engines, but I
haven't been able to track down the CB engine designation used for this
rating.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Thu, Sep 21, 00
at 23:49
Thanks again, Steve!
According to Silverstone, "U.S. Warships since 1945" (names, dates, and
minimal stats), LST 1173, the Suffolk County, was launched in 1956. This was
the first (by launching date, not hull number) of the ships my naval history
internet person said were equipped with 2400 hp "FVAM-16" engines. LSTs don't
take as long to build as, say, battleships, so I think it's safe to say the
design was finalized in 1954 or even 1955: thus the ship is a contemporary of
or later than GE test locomotive 750. Marine diesels, I think, are rated on a
different basis from locomotives: the rated horsepower of a marine diesel is
more nearly comparable to the higher of the two figures ("gross") you quote.
[This higher figure, or something like it, is typically quoted for diesel
locomotives outside North America: evidently in a deliberate effort to confuse
novice railroad historians
] So the 2400 hp rating of the FVAM would
correspond to something like 2180 under the rating convention for North
American locomotives.
Suggesting that 750 was very early for the FVB's 150/165 hp/cyl rating: when
they decided to use the C-B engine as their primary locomotive diesel, GE
evidently asked C-B to "push the envelope" (and the extended testing of 750
was doubtless well worth while).
Do you know the model designation of the engines used in 750 and the UD18B
demos? Were they all equipped with FVBL?
--
PS: I hadn't realized until recently that there were ANY U9B built with C-B
engines: my impression is that GE export loomotives of this size have usually,
since the end of 70-tonner production, had Caterpillar engines. The New
Zealand Railway DH class of 1978 had "CAT D398" engines-- this is a 54
(metric?) ton endcab rated, according to Railmac Publications "NZR
Locomotives", at 630 kw. (Since the same book gives a 1230 kw rating for a
1979 EMD with a 12-645, I'd guess the DH is a "U8" of about 770 hp in North
American rating.) And the GE entry in the 1986-1987 edition of "Jane's World
Railways" lists U10B (1050 gross hp/950 for traction) and a U11B (1100
gross/1000 for traction) with Caterpillar D 379 and D 398 engines,
respectively-- only the larger export models (U15C, U18C,U22C,U26C,U30C) are
shown as having FDL engines (8 cyl for the first two, 12 for the rest).
RE: FDL Origins
Posted by: Michael Schaefer (mbschaefer@-) on Fri, Sep 22, 00 at 2:47
This is probably the most interesting string yet, keep it up. Do you know how
long the 750 tested? And how long on the road, and witch roads?
Mike.
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Fri, Sep 22, 00 at 13:18
Allen, to deal with your PS first, as best I can figure out the original GE
export U-series line, as released late in 1956, included permutations and
combinations on 3 basic frame sizes.
The "big" model was a road switcher that mounted the CB FVBL-12 engine at
1980/1800 hp, and was available in C-C and -1-C-C-1 forms as the U18C and
U18C1 respectively. Only South Africa bought the U18C1 - it needed light axle
loadings (about 23 000 lb) for its South West Africa (now Namibia) lines. Base
weight of the U18C was around 200 000 lb, although standard gauge variants
were usually heavier (ballasted or heavier section frame members, perhaps?)
The "intermediate" model was a slightly shorter road switcher that basically
had the CB FVBL-8 engine at 1320/1200 hp, and was available in B-B (U12B) and
C-C (U12C) variants. Base weight for the U12C was around 180 000 lb.
The same model was also available with the 6 cylinder CB engine at 990/900 hp,
as the U9B and U9C. A handful of U9Bs were sold to Brazil, and a handful of
U9Cs to Chile, but it appears to be been discontinued in 1958 or 1959, i.e.
about the same time that the 70 tonner was discontinued. The only datapoint of
have on weight is for the Red Norte (Chile) U9Cs, which were 78 tonnes, say
roundly 172 000 lb.
The "small" model was a short end-cab utility B-B design with either the Cat
D379 (8 cylinder) or Cat D398 (12 cylinder) engines, model designations
U5B/U6B and U8B respectively. It seems that the D379 version was available at
two power output levels.
Some things I don't know - whether or not the U18 was offered in B-B form
(perhaps for standard/broad gauges only?) or A1A-A1A form; whether or not the
U12/U9 was offered in A1A-A1A or 1-C-C-1 form; whether or not the U6/U8 was
offered in A1A-A1A or C-C form (it would have been a push unless a longer
frame was used, or articulated trucks were fitted, a la export 70 tonner.)
All of the models were progressively increased in power output, sometimes with
different outputs offered concurrently. So the 12 cylinder U18C became the
U20C, then the U22C. The 8 cylinder U12C became the U13C, U15C, U18C then
U20C. The Cat-engined models also underwent changes, although here I'm not
sure of the exact sequence except that the U10B was an early uprating of the
U8B.
The U26C was a later (1971) addition to the range with a longer frame than the
U18C/U20C and with the uprated 12 cylinder engine at 2750/2600 hp. Base weight
was around 215 000 lb, although the first customer, South African Railways,
opted for a heavy frame version.
GE recycles its model numbers, so that for example a late U18C (8 cylinder) is
quite a bit different to an early U18C (12 cylinder). To add to the confusion,
there are modified variants, like UM10B, where the 'M' is generic. I.e. a
UM10B can be either a road switcher variant of the U10B, with a tall short
hood on an apparently lengthened frame, as used in Greece and Spain, or what
appears to be a standard U10B frame with a miniature, low short hood, as used
by some South African industrial operators.
Why GE dropped the U9B/C, and the 6 cylinder engine I don't know. Perhaps it
saw the Cat D398 as better suited to the majority market requirements for
locomotives in this power class, although the sales of the Alco 6 cylinder
models for the next decade or so suggest that there was a substantial niche
for a road locomotive of around 1000 hp or so with a robust medium-speed
engine. The U9B/C was certainly at a disadvantage, weight-wise versus the Alco
DL-532/DL-531; I think the DL-531 could come in a bit below 160 000 lb, which
provided more than enough adhesion for the available power. Who knows, perhaps
GE saw that it couldn’t match Alco in this niche, but didn't consider it
worthwhile spending time and money on a new frame and the including the 6
cylinder engine in its build program. Or, the costs of so doing were estimated
to be more than what it was going to make on the electrical equipment in those
Alcos anyway!
In dropping the 6 cylinder engine it also let go of the C+C export 70 tonner,
which had a very light axle loading of around 23 500 lb, and might have still
found a niche in the 1960s. In a way, Clyde-GM's Australian GL8C and GL18C
models are a latter-day incarnation of the same concept.
Since the GE vs. Alco issue has arisen elsewhere in this forum, it's
worthwhile noting that the 6 cylinder C-C road switcher appeared to be Alco's
only entrant in the market for locomotives suitable for narrow gauge roads
that also had severe axle loading and loading gauge restrictions. All of GE's
U-series models were built to a 12'0" x 9'0" envelope, and to fairly low base
weights. In contrast Alco's 12 cylinder export models, like the DL541,
although of similar power to the U18C, were heavier, taller and wider; they
seemed to have been designed more for roads that were, in a proximate sense,
of UIC dimensions. And in the late 1950s through the late 1960s, Alco didn't
have an 8 cylinder model to put up against the GE U12B/C, either. MLW
rectified the situation with the MX620 and MX615 models circa 1970, and picked
up some useful Cape/meter gauge business in Africa by so doing, but meanwhile
GE's 8 and 12 cylinder models had established and consolidated a significant
sales lead.
One can find antecedents to the initial export U-series models in GE's
early/mid-1950s production, but as this post is already a bit long I'll leave
those comments until a later post.
On GE #750, none of my references mention a model number for its engines;
usually they are described as 'CB 9 x 10.5' , 1200 hp for the 8 cylinder and
1800 hp for the 12 cylinder. Perhaps CB held back from giving them a
production designation until they were fully tested? The UD18 is sometimes
described as having an FDL12 engine, but I wonder if this is not informal
retroactive application of the later designation, in the same way that
U-series labels are sometimes applied to pre-U-series models, e.g. 'U6C' to
the C+C export 70 tonner. Of course, GE's redesignation of #750 as a UM20
after its re-engineing left the door wide open for this practice.
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Fri, Sep 22, 00 at 14:26
Correction: axle loading for the South African U18C1 was about 28 000 lb (12.7
tonnes), not 23 000 lb.
Addition: The New Zealand Dh class were actually U10B models, although
apparently set at 672/615 kW (900/825 hp). Maybe NZR's unhappy earlier
experience with Cat D398 engines in its Mitsubishi-built Dj class had
something to do with this derating.
RE: FDL Origins
Posted by: Michael Schaefer (mbschaefer@-) on Sat, Sep 23, 00 at 3:36
GE dropping the 6cyl engine may have had somthing to do with HP per design
situation. From the stand point of a 9"x10" cylinder bore in a six just to get
900hp, it only makes sense to go with a good smaller higher speed unit that is
more compact and light to do the job, and GE no doubt had the ability to
produce the acompanying gen for the application. The CAT setup probably
allowed more carbody-weight possibilities than the CB design and Im sure that
the low speed of the CB engine made for somewhat less than perfect gen
efficientcy.
Take a look at modern CAT powered locos, they have smaller higher speed
engines(3500 series) and smaller alternators, but the design allows for them
not to need transition pannels like a typical loco, the fact that they can
spin over 1800 rpm(2400???) when the norm is 900 to 1100, they produce a
powerband that goes farther without shunting fields to draw more from the
motors, and this had to be the case with the early GEs. I do not know for sure
but it only makes sense to me based from my experience, I wonder what the
specs and weights were on the early CB-CAT engine/gen units.
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Sun, Sep 24, 00 at 11:16
Mike, I think that you've probably hit the nail right on the head about the
use of the Cat high-speed engines. I remember reading somewhere - can't trace
it now - that in switching service particularly, the low inertia high speed
engine responds much more quickly to throttle changes, and with less harm to
itself.
The Cat 6.25 x 8 engines (D379 & D398) ran at 1300 rev/min; as you say, the
later 3500 series (170 x 190 mm) can run a lot faster. I think that Cat quotes
an operating range of 600 - 1800 rev/min for locomotive applications; I
vaguely recall seeing 2100 rev/min maximum for mine haul truck applications.
The Cat-engined locomotives were certainly noticeably lighter than their CB 6
cylinder counterparts. Base weight for the U8B/U10B/U11B (D398 V12 engine) was
around 110 000 lb, compared with 140 000 lb for the 70 tonner. In fact the
direct antecedents of the Cat-engined U-models seem to be the various end cab,
50 ton B-B models supplied by GE in the early 1950s. I don't know what engines
were used in all of these, but amongst the best known are the US Gypsum pair
described in RF&RR, July 1991. These are described as being a custom design,
similar to the later U4, and having 390 hp Cat D397 engines.
Custom design is I think, stretching it a bit, but understandable as the 50
ton model was probably rare in the US. I don't think that there was ever a U4;
this is more like freestyle retroactive use of the U-series designation
system. Cat D397 is curious; I wonder if it is a misprint for D379. But these
Cat numbers don't follow an obvious sequence, as the 8 cylinder 6.25 x 8
engine is D379, whereas the 12 and 16 cylinder versions are D398 and D399
respectively.
By way of another weight comparison, apparently there were some late (1956)
meter gauge C+C 70 tonners that went to Brazil that were fitted with Cat D398
engines set at 660 hp (gross). These are quoted at 60 tonnes (roundly 132 000
lb) as compared with 64 tonnes (141 000 lb) for their CB-engined counterparts.
If the Cat-engined locos did have essentially identical frames, etc.,
something I've assumed but haven't yet been able to confirm, then the weight
difference is indicative of the advantage accruing to the Cat engine/generator
combination.
As best I can trace, these Brazilian locos were a very early GE application of
the Cat 12 cylinder engine, and seem to be a pointer to GE's ultimate
intentions, although CB-engined C+C 70 tonners were supplied to Chile as late
as 1957, in fact more-or-less concurrently with the U9Cs.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Mon, Sep 25, 00
at 1:19
I can think of at least two other users of small GE endcabs ("U4" style) in
the United States: Southern Pacific used one such unit on their narrow gauge
line before abandonment (their unit was subsequently, I think, sold to some
line in Mexico), and the New York Subway system has a sizeable fleet used on
work trains. Pictures (though not, alas, technical details) on the New York
units should be accessible in two or three link-clicks from the link below.
(Oh. By the way. What were the model numbers and cylinder dimensions of the
eight cylinder (most) and six cylinder (a few late) Caterpillar engines used
on GE 44-tonners?)
Here is a link that might be useful: Rails and Transit
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Tue, Sep 26, 00 at 10:49
As far as I know, the 8 cylinder Cats in the 44 tonners were the D17000 model,
5.75 x 8 inches, naturally aspirated, 190/175 hp at 1000 rev/min, operating
range 350 -1000 rev/min.
I don't know about the 6 cylinder Cats. Maybe D342 models, which were also
5.75 x 8 inches, or D353, 6.25 x 8 inches?
I have left the original discussion 99.9% intact, except for removing users’ e-mail addresses, and inserting line breaks for easier reading.
FDL Origins
Posted by Allen Hazen (a.hazen@-) on Thu, Sep 7, 00 at
21:49
I have been curious about the origins of the FDL engine. Here is a precis of
what I know so far. I post it for the benefit of the curious... and in hopes
of stimulating the knowledgeable into telling me more!
(i) The engine used, starting in the mid 1940s, on the GE 70-tonner (and on
some similarly sized locomotives built by other builders) was an ancestor, the
Cooper-Bessemer "FWL" (or "FWL-T"). Same cylinder dimensions, and I don't know
how much further resemblance (power assembly construction?). Six cylinder,
in-line, lower per-cylinder power rating than the contemporary Alco 244 engine
used on contemporary full-size Alco-GE diesel locomotives.
(ii) A V-configuration version was developed NO LATER THAN 1952: a 12-cylinder
version was used in the locomotives GE built for Queensland (Australia)
Railways in 1952. This was called the "FVL," but had the low output/cylinder
of the first 70-tonners.
(iii) An uprated version-- equal in power/cylinder to the mid-1950s version of
the Alco 244-- existed by 1954, when it was used in the four-unit "Rolling
Laboratory," the GE test locomotive (#750) operated mainly on the Erie
Railroad. GE, which eventually (WHEN?) bought the design and manufactured the
engine themselves, calls this the "FDL".
(iv) I asked on a Naval History web discussion board to see if this had been
used by the U.S. Navy. It was. A class of mid-1950s landing ships ("LST", but
about twice the size of a WW II LST) was powered by six 2400 hp
Cooper-Bessemer "FVAM" engines per ship. (The person who mentioned them called
them the "Suffolk County" class, but Suffolk County was not the first in the
series-- there were about ten ships in the class, so something like 60
sixteen-cylinder C-B engines closely related to the FDL were in U.S. Navy
service before the first FDL-16 was installed in the U25B prototype.)
(v) Is there a system to the model designations? At a guess, "F" is the basic
design, "V" is probably for V-configuration, and-- in Cooper-Bessemer usage--
the final "M" or "L" denotes versions for Marine or Locomotive application.
I'm betting that the "A" in FVAM was for the increased power rating, and that
the engines installed in GE 750 would have been called "FVAL" by C-B at the
time. Was "FDL" ("DL" for Diesel Locomotive) a GE designation, introduced
after they bought the design and applied retroactively to the FVAL engines
used in early U-series locomotives?
(vi) And, as if we needed more evidence that railroad duty is harder on diesel
engines than marine-- note that the U.S. Navy's experience with the FVAM-16
wasn't enough to give the U25B a fully debugged and trouble-free engine.
(I'm afraid I haven't said much here that isn't common knowledge. Sorry.)
Follow-Up Postings:
RE: FDL Origins
Posted by: Michael Schaefer (mbschaefer@-) on Fri, Sep 15, 00 at 4:08
The main reason that marine duty is not as harsh is that the load dosent vary
nearly as much on ships as locomotives. locomotives go from idle to high load
and back every few seconds when switching and they take the shock of the train
slack as well, just try kick switching with out bracing your self in the seat,
and then realize that the loco has to do that all its life.
I will testify that locomotives are the toughest machines on the planet.
But then again Im not sharing any new info in this post.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Sat, Sep 16, 00
at 2:01
Thanks, Mike. It occurs to me that my naval history reading gave an example. A
book (forgotten the author but could find it if anyone wants) called "The
Arnheiter Affair," about the removal of a Lt. Commander Arnheiter from command
of a destroyer escort during the Viet Nam War. The ship was a WW II era ship
with Fairbanks Morse engines very similar to those used in FM locomotives
postwar. One episode reported was about the engineering officer's attempt to
explain to Arnheiter the restrictions on frequency of power change, etc, that
were necesseary to prolong the life of the diesel engines: the Navy can
tolerate operating restrictions that would leave a locomotive totally useless!
In addition, the engine-room of a ship may be a much cleaner and less
vibration-heavy environment than the hood of a locomotive.
RE: FDL Origins
Posted by: Michael Schaefer (mbschaefer@-) on Sat, Sep 16, 00 at 5:08
Absolutly true, even in rough seas a water vessel doesnt even suffer half the
abuse of a locomotive, the cleanliness comes from the fact that there is no
dirt out at sea, even the air is clean once your away from port.
On a locomotive you have nothing more than sheet metal with seams and vents
all over it, with ALCo and GE haveing pressureized car bodies(ALCo 1st), the
dirt still gets in and stays in unless the owner has realy good maintenance.
But its the constant speed and load changes, and the vibration/harmonic/stress
diferantals that cause the most problems in designing loco prime movers. The
severe shocks encountered in service dont help much, getting knocked out of
the seat once and a while makes me wonder how they handle it at all.
Mike.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Sat, Sep 16, 00
at 22:41
Thanks again. I knew that both the duty cycle and the dirty shaky environment
were hard on railroad diesels, but as a non-engineer and amateur, had no idea
which was more serious.
What, by the way, are you referring to in saying that Alco was first with
pressurized carbodies? I thought this was a feature of the U25B that Alco
didn't catch up to until the Century series introduced 3 years or so later.
Have I missed something?
RE: FDL Origins
Posted by: JR (jradtke@-) on Sun, Sep 17, 00 at 9:49
Actually Baldwin was the first builder to offer pressurized bodies. Roto-Clone
air filters were installed on a 15 unit order for the French North Africa RR
in the late forties - early fifties.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Sun, Sep 17, 00
at 21:50
Thank you, JR. Apparently EMD's E-8 and E-9 also had pressurized engine rooms.
Apparently GE (quite correctly) never claimed that the U25B was the FIRST
locomotive with a pressurized carbody, but they did emphasize the centralized
air system as a major innovation, and I thought the U25B was the first modern
hood unit to be pressurized, with EMD and Alco catching up with the GP30 and
the Century line.
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Wed, Sep 20, 00 at 18:31
Allen, here is some data obtained from various sources, with interpolations
and extrapolations, that might add a few more pieces to the FDL puzzle.
CB had established a relationship with GE in the 1930s, and when the FW series
engine was introduced circa 1945, GE locomotive applications were probably
envisaged as a big part of its potential market.
The 'F' in the designation seems to relate to cylinder size (i.e. E was
smaller, G was bigger) but I don't know the significance of the W. Neither do
I know what cylinder configurations the FW was originally available in.
As is well-known, GE first used the 6 cylinder model (FWL-6T) in both the
'domestic' (B-B) and 'export' (C+C) 70 tonner models. As far as I've been able
to trace, its first use of the 12 cylinder model (FVL-12T) was in the 75 tonne
(metric ton) meter gauge A1A-A1A shovel-nose units that went to General
Belgrano in Brazil circa 1949-50. Very similar 77 tonne units went to Chile
shortly afterwards, so the 1952 Queensland road switchers appear to be third
application for this engine.
Some time in the mid-1950s GE asked CB for more powerful engines, particularly
8 and 12 cylinder models, required for its new export model range. It seems
that CB was still GE's preferred supplier, but it may have been reluctant to
spend the development money without certainty of return. So there was a new
agreement, under which GE got its engines on a cost-plus basis, with the right
to undertake manufacture at some time in the future. Under this provision, GE
started assembling 16 cylinder engines circa 1962, using CB-supplied
components, although for a while longer (I don't know how much longer) CB
continued to supply completed 8 and 12 cylinder engines. I haven't been able
to determine when CB completely disengaged itself, and GE assumed total
responsibility for design, development and manufacture.
If one looks at the ratings, the FWL-6T as used in the 70 tonner was 660/600
hp, but as used in the export U9B/C of 1956/57 it was 990/900 hp, or 165/160
hp per cylinder. The same per cylinder ratings applied to the FVL-8T (8
cylinder) used in the export U12B/C(1320/1200 hp) and the FVL-12T (12
cylinder) export U18C (1980/1800 hp). The inference is that CB did whatever
re-engineering was required for the 50% increase in per-cylinder output.
Early FVL-12T applications were at strangely low per cylinder ratings. Local
ambient conditions, or rather derating for these might have explained this in
part, but maybe the early vee variants were not so robust? Perhaps that
unusual articulated rod design was a factor? As long as GE had easy access to
the Alco 12-244 for its more powerful export models, maybe it was prepared to
leave the FVL-12T as it was, or at least leave it to CB's discretion as to
what development work should have been undertaken. But its divorce from Alco
would have changed all of that.
The 8 cylinder export model was modestly uprated to 1420/1300 hp (as the
U13B/C) around 1961, still I believe with what was referred to as a CB engine.
However, the same increment was not applied to the 12 cylinder export model
(as the 2150/2000 hp U20C, with long chopped nose) until 1964, by which time
the engine was described as a GE 7FDL-12.
The next power output increments amongst the export models show up in the U15C
of around 1968 (FDL-8 at 1650/1500 hp) and then the U26C of 1971 (FDL-12 at
2750/2600 hp, alternator, short nose, and high-adhesion trucks).
From this I'd infer that the early GE-built FDLs were not a lot different to
the late CB FWL/FVL models, but that from the mid-1960s, GE was doing a lot of
re-engineering work to increase the specific output of the FDL, and making the
engine "its own".
Many years back I read a GE document that explained the significance of the
various elements of its 7FDL designation and how it fitted in with its general
component designation system, but I never thought to keep a copy. All I recall
now is that the 'L' did indicate locomotive, as one might expect.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Wed, Sep 20, 00
at 22:20
Steve Palmano--
THANK YOU!!!! VERY infomative! (The power ratings got discussed in the 244 and
241 engine strings on the Alco forum a few weeks ago. The C-B "E" engine you
refer to was on the low powered Monongahela Connecting centercab that was
mentioned.)
Perhaps you know the answers to the questions I asked in the "Factory
Questions" string on this forum: in particular, is the Grove City plant where
GE Transportation Systems makes its diesel engines the old C-B plant?
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Thu, Sep 21, 00 at 16:17
Allen, I can't really help you with your factory question. Perhaps like you,
I'm very much an 'outside observer' trying to make sense of information
fragments. Grove City was the original home of the 'Bessemer' part of
Cooper-Bessemer, whereas Cooper came from Mt. Vernon, Ohio. And I think that
for quite a while, Grove City was the main manufacturing point for
Cooper-Bessemer/Cooper Industries reciprocating engines and compressors. So
maybe a part of the plant was sold to GE. And the idea that GE manufactured
7FDL engines at Erie may have arisen during the period when it was assembling
the 16 cylinder models from CB-supplied components.
Here's something additional on the CB engine designations that I should have
looked at again and included in my previous post. (More haste, less speed!)
Evidently the uprated, i.e. 165/150 hp/cylinder, version of the CB FWL/FVL
engine was known as the 'B' series.
Some old South African Railways roster diagrams that I have show its 1958 U12B
fleet (31 class) to have CB FVBL-8 engines (at 1320/1200 hp) and its 1959
U18C1 fleet (32-000 class) to have CB FVBL-12 engines (at 1980/1800 hp).
(SAR's next GEs were its 33-000 class in 1965, low-nose U20C models with GE
7FDL-12 engines at 2150/2000 hp).
By way of a cross-check, Janes 1981-82 has some useful information on the
RFFSA Brazil diesel fleet. The 1958-59 GE U12Bs and U12Cs are shown as having
CB FVBL-8T engines at 1320 hp (gross), and the 1957 GE U9Bs as having CB FWB-6
engines at 990 hp (gross). The C+C 70 tonners (1947-56) are shown as having CB
FWL-6T engines at 660 hp (gross).
There are some differences here, in that the trailing'T' seems to be optional
- maybe it was dropped as being superfluous, as all of the 'B' engines were
turbocharged. And I wonder if the 'FWB-6' should not have been 'FWBL-6'?.
So, the apparent sequence is:
The 'original' versions of the CB 9x10.5 engine as used by GE were the FWL-6T,
at up to 660/600 hp, and the FVL-12T, at up to 1100 hp (net).
The uprated, or 'B' series CB engines, as used by GE in its export U-series
from late 1956, were the FWB(L)-6, FVBL-8, and FVBL-12, all at 165/150 hp per
cylinder. Of course, the 8 and 12 cylinder engines at this rating were
apparently first used in prototype #750. I can't trace any previous use of the
8 cylinder engine by GE, but it may have been used in two pre-U-series models
supplied to Manila Railways in the Philippines in 1956. (Both were Cape gauge
C-C models rated at 1200 hp (net), one being a cab unit (miniature of the
#750/NSW Class 43 concept) and the other combining a shovel-nose front-end
with a road-switcher long-hood body. So far I haven't been able to confirm the
engine type fitted to each.)
GE discontinued the 6 cylinder models around 1958-59 after selling only a
handful of U9B/Cs, so from its perspective at least, the 'V' and 'W'
characters were no longer needed - all engines were vee-form. Into the realm
of speculation, did the FVBL-8 and FVBL-12 metamorphose into the FDL-8 and
FDL-12, the 'V' being dropped and the 'D' representing another engineering
iteration - although then there's a missing 'C' iteration?
The RFFSA list in Janes 1981-82 also shows the 1963 U-13B fleet as having GE
7FDL-8 engines at 1420 hp (gross). However, according to Phil Wormald's GE
export site, 1420 hp U13C s were supplied to Gabon as early as 1960.
Ostensibly, this was when CB was still supplying the 8 cylinder engines, but I
haven't been able to track down the CB engine designation used for this
rating.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Thu, Sep 21, 00
at 23:49
Thanks again, Steve!
According to Silverstone, "U.S. Warships since 1945" (names, dates, and
minimal stats), LST 1173, the Suffolk County, was launched in 1956. This was
the first (by launching date, not hull number) of the ships my naval history
internet person said were equipped with 2400 hp "FVAM-16" engines. LSTs don't
take as long to build as, say, battleships, so I think it's safe to say the
design was finalized in 1954 or even 1955: thus the ship is a contemporary of
or later than GE test locomotive 750. Marine diesels, I think, are rated on a
different basis from locomotives: the rated horsepower of a marine diesel is
more nearly comparable to the higher of the two figures ("gross") you quote.
[This higher figure, or something like it, is typically quoted for diesel
locomotives outside North America: evidently in a deliberate effort to confuse
novice railroad historians

correspond to something like 2180 under the rating convention for North
American locomotives.
Suggesting that 750 was very early for the FVB's 150/165 hp/cyl rating: when
they decided to use the C-B engine as their primary locomotive diesel, GE
evidently asked C-B to "push the envelope" (and the extended testing of 750
was doubtless well worth while).
Do you know the model designation of the engines used in 750 and the UD18B
demos? Were they all equipped with FVBL?
--
PS: I hadn't realized until recently that there were ANY U9B built with C-B
engines: my impression is that GE export loomotives of this size have usually,
since the end of 70-tonner production, had Caterpillar engines. The New
Zealand Railway DH class of 1978 had "CAT D398" engines-- this is a 54
(metric?) ton endcab rated, according to Railmac Publications "NZR
Locomotives", at 630 kw. (Since the same book gives a 1230 kw rating for a
1979 EMD with a 12-645, I'd guess the DH is a "U8" of about 770 hp in North
American rating.) And the GE entry in the 1986-1987 edition of "Jane's World
Railways" lists U10B (1050 gross hp/950 for traction) and a U11B (1100
gross/1000 for traction) with Caterpillar D 379 and D 398 engines,
respectively-- only the larger export models (U15C, U18C,U22C,U26C,U30C) are
shown as having FDL engines (8 cyl for the first two, 12 for the rest).
RE: FDL Origins
Posted by: Michael Schaefer (mbschaefer@-) on Fri, Sep 22, 00 at 2:47
This is probably the most interesting string yet, keep it up. Do you know how
long the 750 tested? And how long on the road, and witch roads?
Mike.
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Fri, Sep 22, 00 at 13:18
Allen, to deal with your PS first, as best I can figure out the original GE
export U-series line, as released late in 1956, included permutations and
combinations on 3 basic frame sizes.
The "big" model was a road switcher that mounted the CB FVBL-12 engine at
1980/1800 hp, and was available in C-C and -1-C-C-1 forms as the U18C and
U18C1 respectively. Only South Africa bought the U18C1 - it needed light axle
loadings (about 23 000 lb) for its South West Africa (now Namibia) lines. Base
weight of the U18C was around 200 000 lb, although standard gauge variants
were usually heavier (ballasted or heavier section frame members, perhaps?)
The "intermediate" model was a slightly shorter road switcher that basically
had the CB FVBL-8 engine at 1320/1200 hp, and was available in B-B (U12B) and
C-C (U12C) variants. Base weight for the U12C was around 180 000 lb.
The same model was also available with the 6 cylinder CB engine at 990/900 hp,
as the U9B and U9C. A handful of U9Bs were sold to Brazil, and a handful of
U9Cs to Chile, but it appears to be been discontinued in 1958 or 1959, i.e.
about the same time that the 70 tonner was discontinued. The only datapoint of
have on weight is for the Red Norte (Chile) U9Cs, which were 78 tonnes, say
roundly 172 000 lb.
The "small" model was a short end-cab utility B-B design with either the Cat
D379 (8 cylinder) or Cat D398 (12 cylinder) engines, model designations
U5B/U6B and U8B respectively. It seems that the D379 version was available at
two power output levels.
Some things I don't know - whether or not the U18 was offered in B-B form
(perhaps for standard/broad gauges only?) or A1A-A1A form; whether or not the
U12/U9 was offered in A1A-A1A or 1-C-C-1 form; whether or not the U6/U8 was
offered in A1A-A1A or C-C form (it would have been a push unless a longer
frame was used, or articulated trucks were fitted, a la export 70 tonner.)
All of the models were progressively increased in power output, sometimes with
different outputs offered concurrently. So the 12 cylinder U18C became the
U20C, then the U22C. The 8 cylinder U12C became the U13C, U15C, U18C then
U20C. The Cat-engined models also underwent changes, although here I'm not
sure of the exact sequence except that the U10B was an early uprating of the
U8B.
The U26C was a later (1971) addition to the range with a longer frame than the
U18C/U20C and with the uprated 12 cylinder engine at 2750/2600 hp. Base weight
was around 215 000 lb, although the first customer, South African Railways,
opted for a heavy frame version.
GE recycles its model numbers, so that for example a late U18C (8 cylinder) is
quite a bit different to an early U18C (12 cylinder). To add to the confusion,
there are modified variants, like UM10B, where the 'M' is generic. I.e. a
UM10B can be either a road switcher variant of the U10B, with a tall short
hood on an apparently lengthened frame, as used in Greece and Spain, or what
appears to be a standard U10B frame with a miniature, low short hood, as used
by some South African industrial operators.
Why GE dropped the U9B/C, and the 6 cylinder engine I don't know. Perhaps it
saw the Cat D398 as better suited to the majority market requirements for
locomotives in this power class, although the sales of the Alco 6 cylinder
models for the next decade or so suggest that there was a substantial niche
for a road locomotive of around 1000 hp or so with a robust medium-speed
engine. The U9B/C was certainly at a disadvantage, weight-wise versus the Alco
DL-532/DL-531; I think the DL-531 could come in a bit below 160 000 lb, which
provided more than enough adhesion for the available power. Who knows, perhaps
GE saw that it couldn’t match Alco in this niche, but didn't consider it
worthwhile spending time and money on a new frame and the including the 6
cylinder engine in its build program. Or, the costs of so doing were estimated
to be more than what it was going to make on the electrical equipment in those
Alcos anyway!
In dropping the 6 cylinder engine it also let go of the C+C export 70 tonner,
which had a very light axle loading of around 23 500 lb, and might have still
found a niche in the 1960s. In a way, Clyde-GM's Australian GL8C and GL18C
models are a latter-day incarnation of the same concept.
Since the GE vs. Alco issue has arisen elsewhere in this forum, it's
worthwhile noting that the 6 cylinder C-C road switcher appeared to be Alco's
only entrant in the market for locomotives suitable for narrow gauge roads
that also had severe axle loading and loading gauge restrictions. All of GE's
U-series models were built to a 12'0" x 9'0" envelope, and to fairly low base
weights. In contrast Alco's 12 cylinder export models, like the DL541,
although of similar power to the U18C, were heavier, taller and wider; they
seemed to have been designed more for roads that were, in a proximate sense,
of UIC dimensions. And in the late 1950s through the late 1960s, Alco didn't
have an 8 cylinder model to put up against the GE U12B/C, either. MLW
rectified the situation with the MX620 and MX615 models circa 1970, and picked
up some useful Cape/meter gauge business in Africa by so doing, but meanwhile
GE's 8 and 12 cylinder models had established and consolidated a significant
sales lead.
One can find antecedents to the initial export U-series models in GE's
early/mid-1950s production, but as this post is already a bit long I'll leave
those comments until a later post.
On GE #750, none of my references mention a model number for its engines;
usually they are described as 'CB 9 x 10.5' , 1200 hp for the 8 cylinder and
1800 hp for the 12 cylinder. Perhaps CB held back from giving them a
production designation until they were fully tested? The UD18 is sometimes
described as having an FDL12 engine, but I wonder if this is not informal
retroactive application of the later designation, in the same way that
U-series labels are sometimes applied to pre-U-series models, e.g. 'U6C' to
the C+C export 70 tonner. Of course, GE's redesignation of #750 as a UM20
after its re-engineing left the door wide open for this practice.
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Fri, Sep 22, 00 at 14:26
Correction: axle loading for the South African U18C1 was about 28 000 lb (12.7
tonnes), not 23 000 lb.
Addition: The New Zealand Dh class were actually U10B models, although
apparently set at 672/615 kW (900/825 hp). Maybe NZR's unhappy earlier
experience with Cat D398 engines in its Mitsubishi-built Dj class had
something to do with this derating.
RE: FDL Origins
Posted by: Michael Schaefer (mbschaefer@-) on Sat, Sep 23, 00 at 3:36
GE dropping the 6cyl engine may have had somthing to do with HP per design
situation. From the stand point of a 9"x10" cylinder bore in a six just to get
900hp, it only makes sense to go with a good smaller higher speed unit that is
more compact and light to do the job, and GE no doubt had the ability to
produce the acompanying gen for the application. The CAT setup probably
allowed more carbody-weight possibilities than the CB design and Im sure that
the low speed of the CB engine made for somewhat less than perfect gen
efficientcy.
Take a look at modern CAT powered locos, they have smaller higher speed
engines(3500 series) and smaller alternators, but the design allows for them
not to need transition pannels like a typical loco, the fact that they can
spin over 1800 rpm(2400???) when the norm is 900 to 1100, they produce a
powerband that goes farther without shunting fields to draw more from the
motors, and this had to be the case with the early GEs. I do not know for sure
but it only makes sense to me based from my experience, I wonder what the
specs and weights were on the early CB-CAT engine/gen units.
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Sun, Sep 24, 00 at 11:16
Mike, I think that you've probably hit the nail right on the head about the
use of the Cat high-speed engines. I remember reading somewhere - can't trace
it now - that in switching service particularly, the low inertia high speed
engine responds much more quickly to throttle changes, and with less harm to
itself.
The Cat 6.25 x 8 engines (D379 & D398) ran at 1300 rev/min; as you say, the
later 3500 series (170 x 190 mm) can run a lot faster. I think that Cat quotes
an operating range of 600 - 1800 rev/min for locomotive applications; I
vaguely recall seeing 2100 rev/min maximum for mine haul truck applications.
The Cat-engined locomotives were certainly noticeably lighter than their CB 6
cylinder counterparts. Base weight for the U8B/U10B/U11B (D398 V12 engine) was
around 110 000 lb, compared with 140 000 lb for the 70 tonner. In fact the
direct antecedents of the Cat-engined U-models seem to be the various end cab,
50 ton B-B models supplied by GE in the early 1950s. I don't know what engines
were used in all of these, but amongst the best known are the US Gypsum pair
described in RF&RR, July 1991. These are described as being a custom design,
similar to the later U4, and having 390 hp Cat D397 engines.
Custom design is I think, stretching it a bit, but understandable as the 50
ton model was probably rare in the US. I don't think that there was ever a U4;
this is more like freestyle retroactive use of the U-series designation
system. Cat D397 is curious; I wonder if it is a misprint for D379. But these
Cat numbers don't follow an obvious sequence, as the 8 cylinder 6.25 x 8
engine is D379, whereas the 12 and 16 cylinder versions are D398 and D399
respectively.
By way of another weight comparison, apparently there were some late (1956)
meter gauge C+C 70 tonners that went to Brazil that were fitted with Cat D398
engines set at 660 hp (gross). These are quoted at 60 tonnes (roundly 132 000
lb) as compared with 64 tonnes (141 000 lb) for their CB-engined counterparts.
If the Cat-engined locos did have essentially identical frames, etc.,
something I've assumed but haven't yet been able to confirm, then the weight
difference is indicative of the advantage accruing to the Cat engine/generator
combination.
As best I can trace, these Brazilian locos were a very early GE application of
the Cat 12 cylinder engine, and seem to be a pointer to GE's ultimate
intentions, although CB-engined C+C 70 tonners were supplied to Chile as late
as 1957, in fact more-or-less concurrently with the U9Cs.
RE: FDL Origins
Posted by: Allen Hazen (a.hazen@-) on Mon, Sep 25, 00
at 1:19
I can think of at least two other users of small GE endcabs ("U4" style) in
the United States: Southern Pacific used one such unit on their narrow gauge
line before abandonment (their unit was subsequently, I think, sold to some
line in Mexico), and the New York Subway system has a sizeable fleet used on
work trains. Pictures (though not, alas, technical details) on the New York
units should be accessible in two or three link-clicks from the link below.
(Oh. By the way. What were the model numbers and cylinder dimensions of the
eight cylinder (most) and six cylinder (a few late) Caterpillar engines used
on GE 44-tonners?)
Here is a link that might be useful: Rails and Transit
Re: FDL Origins
Posted by: Steve Palmano (stevepalmano@-) on Tue, Sep 26, 00 at 10:49
As far as I know, the 8 cylinder Cats in the 44 tonners were the D17000 model,
5.75 x 8 inches, naturally aspirated, 190/175 hp at 1000 rev/min, operating
range 350 -1000 rev/min.
I don't know about the 6 cylinder Cats. Maybe D342 models, which were also
5.75 x 8 inches, or D353, 6.25 x 8 inches?
Last edited by MEC407 on Wed Aug 15, 2007 10:08 am, edited 1 time in total.
MEC407
Moderator:
Pan Am Railways — Boston & Maine/Maine Central — Delaware & Hudson
Central Maine & Quebec/Montreal, Maine & Atlantic/Bangor & Aroostook
Providence & Worcester — New England — GE Locomotives
Moderator:
Pan Am Railways — Boston & Maine/Maine Central — Delaware & Hudson
Central Maine & Quebec/Montreal, Maine & Atlantic/Bangor & Aroostook
Providence & Worcester — New England — GE Locomotives