So It seems it all comes down to reliability not fuel consumption seeing the gph/hp equation. How does reliability stack up today with the C44-9 and the SD70- both have been around for over 10 years(not including SD70ACe or GE's new EVO) is one more reliabale than the other. I know GE out sells EMD but there are so many older EMD's out there it would seem EMD might have the edge in reliability. Joe.
Your very right. A C44-9 has 6 fewer TM's and 16 fewer PA's than a set of SD40-2's. However when you look at the numbers I get every morning and the units i have in my shop, the added savings of unit reduction tend to vanish when looking at an availibility of 87%( +/- 2%) for the C44-9's and 97% (+/- 2%) on a daily basis it can be a much better decision for the operating dept. to keep the 3 GM's on the train VS the toasters. a locomotive in the shop does nothing but cost money.
You're right, the notion that SD45s were fuel hogs is solidly ingrained into the conventional wisdom, and it always will be-- tho I've never seen anybody try to give figures to support it. Maybe what happened was-- people look at the SD45's continuous TE and minimum continuous speed, and they notice that they're about the same as the SD40's. The two can drag the same maximum tonnage, and they pull it at the same speed-- and people have assumed that in that situation the SD45 is burning 20% more fuel.
carnej1 Zeroing in on 16 cylinder versus 20 cylinder 645 EMD's fuel consumption, what about at lower throttle settings in low speed "drag" service"? My admittedly novice understanding is that the 600 extra HP from the additional 4 cylinders was mainly a benefit in high speed service. I note that most of the roads that bought the SD45-2(EL,ATSF,SP(alright SD45T-2 in their case)) bought them for that type of work (Clinchfield being an exception)..
Zeroing in on 16 cylinder versus 20 cylinder 645 EMD's fuel consumption, what about at lower throttle settings in low speed "drag" service"? My admittedly novice understanding is that the 600 extra HP from the additional 4 cylinders was mainly a benefit in high speed service. I note that most of the roads that bought the SD45-2(EL,ATSF,SP(alright SD45T-2 in their case)) bought them for that type of work (Clinchfield being an exception)..
I don't have the specific gallons/horsepower/hour curves for all of the locomotives, though looking at the gallons/hour rates for notch 5 across the locomotive choices of the SD45 era, the SD45 is not noticeably more fuel-thirsty for its rated horsepower than an SD40 for its rated horsepower.
The 5th notch question isn't what concerns railroads the most, however. Generally a railroad wants to make sure the locomotive is working in the 8th notch all the time except when it's going down hill. If it isn't, then someone at the railroad is wasting money, either by overpowering the train, or buying too much locomotive, or both. In drag freight service, the locomotive is almost always in the 8th notch except when going downhill, because the train is powered with just enough to get its tonnage over the road and usually can't even make maximum authorized track speed.
I wonder who in the railfan press said that 600 hp additional of the SD45 was only beneficial when the train reached high speeds. (Unless by "high speeds" they were thinking "18-20 mph" instead of "50-60 mph.") It's a claim that has resonated, even though it's nonsense. Only at the very bottom of the speed regime of a locomotive at the time the SD45 was in production might high horsepower be unusable, because it started to exceed the adhesion capability of a locomotive in the era when the best that was available was IDAC wheel-slip control. At minimum continuous speed, a high-horsepower locomotive might be slippery and have to reduce horsepower output. But at a speed only a few mph faster than MCS, adhesion was not limiting and the full horsepower could be brought to bear. A GP40, for example, was attempting to put 750 hp per traction motor onto the rail, whereas an SD40 only 500 and an SD45 600. The argument that an SD45 could only bring its extra 600 hp into use at high speeds doesn't much explain why GP40s even existed, much less sold in large numbers.
RWM
Railway Man I'm mystified why conventional wisdom has it that GEs are more fuel-efficient than EMDs, and SD45s were fuel hogs. Neither is true. At notch 8, the numbers are: SD45, 194 gph = 18.55 hp/gallon/hour SD40-2, 164 gph = 18.29 hp/gallon/hour SD70MAC, 191.9 gph = 20.84 hp/gallon/hour U30C, 155 gph = 19.35 hp/gallon/hour C30-7, 162.7 gph = 18.44 hp/gallon/hour C44-9, 210 gph = 20.9 hp/gallon/hour Note that the: SD70MAC and C44-9 are virtually identical the SD45 delivered a little more horsepower per gallon than the SD40-2 the C30-7 actually delivered less horsepower per gallon than the U30C it replaced. What matters is total lifetime cost (lease price + maintenance cost), and availability, and how much it costs to obtain that availability. A locomotive that is not able to be dispatched on a train is nothing but a burden on the cash flow of a railroad, so much so that even a locomotive with better fuel economy will have a cost hole it can't dig out of even if its fuel economy is significantly better than the one out working. But as we can see, the fuel economy achieved by the two major builders at any comparable chronological point are not substantially different, thus we should probably look to maintenance cost, availability, and initial purchase price. Assembly quality has a large bearing on maintenance cost and availability, and nothing rankles more than a new locomotive with warranty problems and quality defects, because from a mechanical department officer's perspective, a new locomotive that isn't out working is a deadly career-killer -- it shoots down his entire argument that the new power is a better deal than eking out another year with the old. Purchase price varies a great deal, too. No one pays list price on heavy capital goods; each order is individually negotiated. Large manufacturing concerns frequently make a strategic decision to buy market share by slashing their profit margins to nothing in the hope that they'll hurt their competitor's cash flow enough to harm the competitor's R&D efforts, or to build up such a large installed base that their future customers find it more effective to deal with them to minimize parts inventory, training, and regulatory costs. It's a high-stakes game and often the companies that attempt to buy market share end up killing themselves in the long run, because they've starved themselves of cash flow. Investors in such companies are often surprised later that the rapid increase in sales of the company they're investing in had nothing to do with a better product, only a high-risk sales scheme. RWM
I'm mystified why conventional wisdom has it that GEs are more fuel-efficient than EMDs, and SD45s were fuel hogs. Neither is true.
At notch 8, the numbers are:
Note that the:
What matters is total lifetime cost (lease price + maintenance cost), and availability, and how much it costs to obtain that availability. A locomotive that is not able to be dispatched on a train is nothing but a burden on the cash flow of a railroad, so much so that even a locomotive with better fuel economy will have a cost hole it can't dig out of even if its fuel economy is significantly better than the one out working. But as we can see, the fuel economy achieved by the two major builders at any comparable chronological point are not substantially different, thus we should probably look to maintenance cost, availability, and initial purchase price.
Assembly quality has a large bearing on maintenance cost and availability, and nothing rankles more than a new locomotive with warranty problems and quality defects, because from a mechanical department officer's perspective, a new locomotive that isn't out working is a deadly career-killer -- it shoots down his entire argument that the new power is a better deal than eking out another year with the old.
Purchase price varies a great deal, too. No one pays list price on heavy capital goods; each order is individually negotiated. Large manufacturing concerns frequently make a strategic decision to buy market share by slashing their profit margins to nothing in the hope that they'll hurt their competitor's cash flow enough to harm the competitor's R&D efforts, or to build up such a large installed base that their future customers find it more effective to deal with them to minimize parts inventory, training, and regulatory costs. It's a high-stakes game and often the companies that attempt to buy market share end up killing themselves in the long run, because they've starved themselves of cash flow. Investors in such companies are often surprised later that the rapid increase in sales of the company they're investing in had nothing to do with a better product, only a high-risk sales scheme.
"I Often Dream of Trains"-From the Album of the Same Name by Robyn Hitchcock
trainfan1221As noted, at the time EMD needed to go to 20 cylinders to get what GE could from the same 16 cylinder engine. Although they got it up to 4200 as pointed out, but the SD45X didn't go far. What a brute at that time though! The GE engine was their constant improvement on the original design, which I believe was originated by Cooper Bessemer and bought outright by GE. I had read that the way they got to 3600hp was by using a different kind of piston, apparently they didn't need to for the U33C.
As noted, at the time EMD needed to go to 20 cylinders to get what GE could from the same 16 cylinder engine. Although they got it up to 4200 as pointed out, but the SD45X didn't go far. What a brute at that time though!
The GE engine was their constant improvement on the original design, which I believe was originated by Cooper Bessemer and bought outright by GE. I had read that the way they got to 3600hp was by using a different kind of piston, apparently they didn't need to for the U33C.
It should be noted though that the SD45 appeared about 2 years before the first U36C. And most of the U36Cs were retired before the oldest SD45s were retired.
The Metallurgy and shaping of the piston crown was not up to the job on early U33 and U36 locomotives, and so GE had big warranty problems (As did Alco). EMD avoided these problems by going to 20-cylinder diesel to achieve this, the downside for EMD was the flexing of the crankshaft leading to premature failure. EMD was able to solve the crankshaft problem before GE solved the piston problem.
If you do the math however a PAIR of C44-9 still use 72 gallons of fuel LESS per hour than a trio of SD40-2 that they replace on a 2 for 3 basis so there is a fuel cost savings there also. Plus there would be a Maintance savings 16 clyinders 6 traction motors and other parts less that could go down.
Tugboat Tony Hit it exactly on the head. In the 70's the HP race subsided quite a bit and it all came down to reliability. even to this day the SD40-2's at 30+ years old are still turning out 97% or better avalibility.
Hit it exactly on the head. In the 70's the HP race subsided quite a bit and it all came down to reliability. even to this day the SD40-2's at 30+ years old are still turning out 97% or better avalibility.
I know that fuel prices throughout the Seventies were also a major issue for the RR's and probably influenced a lot of orders for 3000 HP as opposed to 3300-3600 HP units...
Much like the change from SD40 to SD40-2, the GE change from U series to Dash-7 series, cleaned up mistakes made in internal layout of components inside the locomotive body, and incorporated many small changes that were happening. Modular electronics appeared in GE locomotives with the production of the "XR" (eXtra Reliability) series during later U series production. With the change to Dash-7 production GE revamped the electrical cabinet, the oil-cooler group, the radiator group, and some lesser changes, to make GE locomotives easier to maintain.
Just out of curiousity, what's the difference (if any, though I'm sure there is) between the U30C and the C30-7, or even the U-series and the C-series in general? They don't look all that different to me, except for the C30-7's rear radiators flare out more than the U30C. Forgive my ignorance.
GE 7FDL engine has 667 cu. in. per cylinder
EMD 645 series engine has 645 cu. in. per cylinder
EMD SD50 locomotives were rated at 3600hp. with a 16-645F engine and achieved GE like reliability. It took until the debut of the Dash-8s for GE to push the ratings higher with an acceptable reliability. GE's GEVO engine is larger displacement still than the FDL. Do you have the specific fuel consumption figures for the GE and EMD engines? The number of cylinders isn't paticularly relevant.
Here is the mystery. EMD had to put 20 cylinders to get 3600HP out of the 645 series YET GE which everyone here seems to hate I swear got 3300-3600 all the way up to 4400 hp with the same Stroke and BORE on the FDL that it had when it was designed in the 50's Yes they made Improvements to it however you could take a mechanic that was trained on one now and tell him to repair one that was built in the 70 and he could more than likely could because the design is the same. EMD however had to come out with the 710 series to reach the 4000hp plateau in Regular production in fact the first redesign was for the EVO series for GE in over 40 years. Look at the curent designs you have a engine that makes 4400 out of 12 cylinders vs one that needs 16 to do the same thing and burns more fuel to do it which one would you if you were the bean counters buying the fuel at 2 bucks a gallon buy considering that they cost the same to buy roughly.
trainfan1221 At the time it seemed that anything over 3000hp wasn't worth it. EMD actually could get 3300hp out of the 16 cylinder engine, as in the DD40AX. I would guess it wasn't worth the extra power either, though supposedly Amtrak's F40s had 3200hp.
At the time it seemed that anything over 3000hp wasn't worth it. EMD actually could get 3300hp out of the 16 cylinder engine, as in the DD40AX. I would guess it wasn't worth the extra power either, though supposedly Amtrak's F40s had 3200hp.
EMD even got 4200 hp out of the 20-645 with several SD45Xs for SP just prior to the Dash-2 line. Only 7 were built, and these had 4 fans above the radiators instead of the usual 3.
Reliability is exactly the word, can't improve on that reply. I was sitting in with Operator Al Wheelock in Flagstaff one night and heard this exchange over the Santa Fe's radio system:
DS: What is the status of the 8500?
Engineer: That oil pot ran about one foot out of Needles Yard and we drug it the rest of the way uphill.
Westbound pig train at milepost 335 of the Santa Fe's Albuquerque Division.
The higher horsepower GEs with the 16-cylinder diesel were less reliable as the horsepower was increased. This is the reason that the NS runs their new GEs and SD70M-2s at only 4000hp. while everybody else runs them at 4400hp or 4300hp. NS doesn't feel that the higher maintenance cost from running the locomotives at the higher rating are worthwhile.
In the late 60s EMD, GE and Alco all came out with over 3000hp locos in addition to their 3000hp units. EMD's SD45 had a 20 cylinder 645, while the GE U36C and Alco C636 offerings were able to stick with the same 16 cylinders as their 3000hp counterparts. GE also had the in-between U33C. Just wondering why the U30C, and later C30-7, were more successful than their 3300 and 3600 counterparts even though both had 16 cylinder prime movers too. The SD45 had a more thirsty 20 cylinder 645 with crankshaft problems, so it's easy to understand railroads choose the SD40/40-2 when fuel prices went up in the 1970s. Maybe some class 1s wanted their GE's to match the hp rating of their 40/40-2s, or maybe the higher hp FDL on over-3000hp u-boats/early Dash-7s, pre-dash 8s tended to get overstressed, or maybe they had wheel slip issues?
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