The Alaskan railroad asked about GP69s. What would it take to make A GP60 into a GP69.
That's a new one on me. Was this before they tested out radial C-C trucks and bought the SD70MAC's?
If I had to take a guess, it would've been a GP59 updated with the advancements made with the 70 series.
IA and easternWhat would it take to make A GP60 into a GP69.
I believe you'd derate a "GP70", or more precisely use the systems of a -70 series with a turbo 12-710 or equivalent for the lower power.
They bought SD-70s instead - with the radial trucks they are actually better on curves than something with B trucks, and the added weight of the HEP equipment posed less of an issue.
Would the current SD30C-ECO series rebuilds qualify as a SD69?
UP called their original batch SD59MX's, as they were rebuilt from SD60M's.
Greetings from Alberta
-an Articulate Malcontent
I wonder had this been built, if it would've rode on their radial B-B trucks that Trains Magazine once said had been designed (But I believe never tested).
In the mid 1990's, EMD was pushing their radial truck as a major advance. So I suspect had there been a GP70 family, some may have rode on radial trucks.
We'll obviously never know for sure, but I'd be curious if it was in any of the proposals if there was serious conversation here about a GP69 between the Alaskan Railway and EMD.
Leo_AmesIn the mid 1990's, EMD was pushing their radial truck as a major advance. So I suspect had there been a GP70 family, some may have rode on radial trucks.
If I remember correctly, there was something about the 70-series that was *just* heavy enough that it wouldn't translate effectively to four-axle without high relative axle loading. If I remember correctly it was a combination of the cooling system component weight and required length to accommodate it effectively.
Two-axle radial steering is not a fun thing geometrically. On the C truck you can have the center axle as the reference position, and the other axles steered with levers as with radiating axles. On a B truck you need to use the truck frame as a reference relative to the carbody, and there's a certain amount of unsprung mass from the steering arrangements over what makes for best suspension performance; the Europeans tried a couple of approaches but not with what I'd call particular success over just good lateral.
I have looked for some time to see what actual detail-design drawings for the EMD radial B truck might have been developed. The patent drawings I've seen aren't particularly convincing as a high-speed improvement over what a good three-axle radial-steering setup can provide. I would be delighted to find out that something good was actually worked out.
Leo_AmesI wonder had this been built, if it would've rode on their radial B-B truck that Trains Magazine once said had been designed (But I believe never tested).
It was tested. Lots of info on this thread
http://cs.trains.com/trn/f/741/t/150535.aspx
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
oltmannd Leo_Ames I wonder had this been built, if it would've rode on their radial B-B truck that Trains Magazine once said had been designed (But I believe never tested). It was tested. Lots of info on this thread http://cs.trains.com/trn/f/741/t/150535.aspx
Leo_Ames I wonder had this been built, if it would've rode on their radial B-B truck that Trains Magazine once said had been designed (But I believe never tested).
Hot link
That's not the 2 axle radial truck that Trains said EMD developed. I don't even think it qualifies as a radial truck and it certainly was never meant to go under a Geep.
Looking around the internet, a Trainorders post makes it sound like a 2 axle radial truck was road tested in the mid 1980's.
https://www.trainorders.com/discussion/read.php?18,4647590
Leo_AmesThat's not the 2 axle radial truck that Trains said EMD developed. I don't even think it qualifies as a radial truck and it certainly was never meant to go under a Geep.
Keep in mind that one of the key provisions of patent 4485743 was to provide steering between the two truck frames, perhaps one of the reasons they were so short in the tested instantiation. While Scheffel didn't think of this as a true 'radial' arrangement, it can be thought of as an analogue of a "B" radial truck (with opposite steering levers for the axles, not the 'best' solution) which uses the two-axle frames as the analogues for the individual steerable axles.
Presumably (and it certainly appears this was a part of the presumption at the time) the flexibility of the Flexicoil arrangement would provide enough lateral on the individual short-wheelbase trucklets to keep them reasonably guiding over the short span of their own wheelbase -- more modern arrangements would provide still more flexibility, if not true axle steering, in that respect.
I suspect a goodly part of the 'failure to thrive' was the additional cost and complexity of the arrangement, four motors and three complex castings or fabrications instead of, essentially, one for the HTCR truck which happily gave zero effective wheelbase and mutual steering with only three or two motors, and adequate adhesion for the required horsepower (I might add, both then and now).
For reference you can study the original Goding patent for the HTCR truck (which, you may note, explicitly but without much further comment calls for a three-axle configuration). The drawings here (the British patent for the Goding design) may be easier for some to read.
Some of what's involved in a radial-steering B truck is covered in this patent from 1981, which covers some methods of providing steering and necessary flexibility.
AQlaska was looking at rebuilding a SD40-2 with radial trucks but no money for experments. The SD70MAC came a good cost so they went with those. Before they went with more SD70MACs,they also looked at SD70I and F69PH and GP69. The Alaska railroad decided that more SD70MACs was the way to go. Gary
With the mention of 2-axle radial trucks in thread, I thought I would chime in.
Along with a colleague, I did design and successfully tested a 2-axle radial truck prior to designing the HTCR truck. This patent shows the design:
https://pdfpiw.uspto.gov/.piw?Docid=04841873&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO2%2526Sect2%3DHITOFF%2526p%3D1%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsearch-bool.html%2526r%3D1%2526f%3DG%2526l%3D50%2526co1%3DAND%2526d%3DPTXT%2526s1%3D4,841,873.PN.%2526OS%3DPN%2F4,841,873%2526RS%3DPN%2F4,841,873&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page
This was tested in 1986 under a Santa Fe GP50 at the Transportation Test Center in Pueblo and on Raton Pass. This was the second two axle truck we tested; the first was built using the cast frame from an HT-B truck with a very simple fabricated bolster which proved the concept of the steering beams carried over to the HTCR. The fabricated frame of the one shown in the patent referenced was not structurally developed for production but it served the purpose for development of a workable arrangement axle steering arrangement. Once this test proved the concept, we immediately started work on the 3-axle design which was the real goal of the project. We never seriously looked again at producing a production 2-axle radial truck.
Most recently, I did the design for the fabricated frame HTCR-6 truck under the EMD tier 4 locomotive as well as the 4-axle articulated truck under the SD70ACe-BB built in Brazil.
Dave Goding
Dave: Good to see that you are still around, wondering what happened to you.
Unexpected, and very great, pleasure to have you in the discussion!
Do you have a good link for patent 4628824, which seems to have disappeared from any sort of linkable patent database?
Thanks for the kind words. It has been a while since I looked and posted here.
Patent 4628824 was the first patent filed and shows the design of what we called the pre-prototype, which was designed to quickly test the feasibility of a powered radial truck for curves of 10 degrees or greater. It was cobbled together using a spare HT-B frame we had in inventory and tested under SF GP50 3810 in Nov. 1984. This link shows the patent: http://www.freepatentsonline.com/4628824.pdf
Rather than posting more info here, I will create a new thread covering the development of the radial truck at EMD.
Dave
What excellent information, thank you for posting this!
As one who operates your team's designs on a daily basis, my hat's off to you. The radial trucks provide a much smoother ride and noticeably superior traction, especially in curves.
Same goes for the WhisperCab, which I'm sure has helped save the hearing of many railroaders over the years.
SD70DudeSame goes for the WhisperCab, which I'm sure has helped save the hearing of many railroaders over the years.
If only railroaders ever listened in the first place. [/sarcasm]
Never too old to have a happy childhood!
BaltACD SD70Dude Same goes for the WhisperCab, which I'm sure has helped save the hearing of many railroaders over the years. If only railroaders ever listened in the first place. [/sarcasm]
SD70Dude Same goes for the WhisperCab, which I'm sure has helped save the hearing of many railroaders over the years.
WHAT!?
On another note, I've always thought the perfect initials for many a Dispatcher would be G.O.D.....
SD70Dude BaltACD SD70Dude Same goes for the WhisperCab, which I'm sure has helped save the hearing of many railroaders over the years. If only railroaders ever listened in the first place. [/sarcasm] WHAT!? On another note, I've always thought the perfect initials for many a Dispatcher would be G.O.D.....
I have known a few who had those initials. They tended to live them.
Overmod IA and eastern What would it take to make A GP60 into a GP69. I believe you'd derate a "GP70", or more precisely use the systems of a -70 series with a turbo 12-710 or equivalent for the lower power. They bought SD-70s instead - with the radial trucks they are actually better on curves than something with B trucks, and the added weight of the HEP equipment posed less of an issue.
IA and eastern What would it take to make A GP60 into a GP69.
The GP59 has a 12-710G3A rated at 3200 HP. In that sense.. I don't see the purpose of a proposed GP69?
I think the SD70 brand was a marketing choice. Like the GP30 name instead of GP22. Or the GP/SD35, which were only a 250/100 HP increase over the previous GP30 and SD24.
Same for the SD80, which really should have been called the SD75, except EMD had already used that for a higher output version of the 16-710.
I could go on all day about the inconsistency of EMD's locomotive model names, but I'm sure they all made sense at the time.
SD70Dude I think the SD70 brand was a marketing choice. Like the GP30 name instead of GP22. Or the GP/SD35, which were only a 250/100 HP increase over the previous GP30 and SD24. Same for the SD80, which really should have been called the SD75, except EMD had already used that for a higher output version of the 16-710. I could go on all day about the inconsistency of EMD's locomotive model names, but I'm sure they all made sense at the time.
Yeah EMD's model nomenclature is very confusing at times to say the least.. GE always had the most sensible model descriptions.
In 2004, shortly before I retired with GM's sale of EMD, I was working special projects at EMD and was tasked with putting together a concept for a GP68, a DC traction loco with 12-710 at 3,200 traction HP. IIRC, NS was the customer who was interested. I had forgotten about it but found a spreadsheet today that I had put together at the time comparing a version based on the layout of the SD70 and a version based on the SD70M-2. It was to use standard GP swinghanger trucks from trade-in locos. The clear winner was the version based on the SD70; at that time the SD70M-2 was still on the drawing board. It would have had a mechanical traction motor blower using the design for the SD70MAC as the lowest cost. It also would have used the narrow nose cab from the SD70. The goal of the design was fast to market, minimize engineering effort, and lowest production cost. While I was at it, I also put together an SD version. Obviously, neither ever got off the drawing board.
I and others at EMD did a lot of other loco designs that never went past a concept design but we were always creating new loco ideas and responding to customer inquiries.
bogie_engineer In 2004, shortly before I retired with GM's sale of EMD, I was working special projects at EMD and was tasked with putting together a concept for a GP68, a DC traction loco with 12-710 at 3,200 traction HP. IIRC, NS was the customer who was interested. I had forgotten about it but found a spreadsheet today that I had put together at the time comparing a version based on the layout of the SD70 and a version based on the SD70M-2. It was to use standard GP swinghanger trucks from trade-in locos. The clear winner was the version based on the SD70; at that time the SD70M-2 was still on the drawing board. It would have had a mechanical traction motor blower using the design for the SD70MAC as the lowest cost. It also would have used the narrow nose cab from the SD70. The goal of the design was fast to market, minimize engineering effort, and lowest production cost. While I was at it, I also put together an SD version. Obviously, neither ever got off the drawing board. I and others at EMD did a lot of other loco designs that never went past a concept design but we were always creating new loco ideas and responding to customer inquiries. Dave
In 2004!!! they were looking for four axle DC road switchers? Yeesh. There's no ROI for that. Luddites. Last to the AC locomotive party, too.
When looking at their rebuild programs in the 2000's, it doesn't really surprise me.
NS has been heavily involved in modernization programs for their 4 axle EMD fleet. Altoona as I type this is even currently building a Tier 4 capable GP34ECO.
So it doesn't surprise me that they were considering purchasing some new units akin to all the GP59E's, GP59ECO's, and GP33ECO's that NS has created from GP50 and GP59 cores in the 2000's and paired with road slugs.
Leo_Ames When looking at their rebuild programs in the 2000's, it doesn't really surprise me. NS has been heavily involved in modernization programs for their 4 axle EMD fleet. Altoona as I type this is even currently building a Tier 4 capable GP34ECO. So it doesn't surprise me that they were considering purchasing some new units akin to all the GP59E's, GP59ECO's, and GP33ECO's that NS has created from GP50 and GP59 cores in the 2000's and paired with road slugs.
You buy new locomotives when they are a better deal than rebuilding what you already have. New locomotive ROI can come from fuel savings, maintenance savings and a reduction in fleet size.
When you are using a four axle locomotive in yard and local service, it generally doesn't burn enough fuel to generate meaningful savings. It also is rather "kind" on the mechanical parts as it isn't working very hard, when it is working, and since you are generally not adding units to cover train tonnage, your replace ration would be 1:1 with a new locomotive.
Unless the locomotive has some horrible flaws, it's almost always better to rebuild what you have, even rather extensively, than buy new.
NS's ECO rebuilds are for use in air quality non-attainment zones (Atlanta and Chicago, in particular) and were done in part with government grants.
NS has been cleaver about their four axle rebuilds, going as far as plopping new cabs on them when the old ones were shot. It's going to take something like a plug - in hybrid or fuel cell based locomotive to generate enough savings to dethrone GP/SD40-2s from yard and local service.
NS hasn't been shy at chasing grant money in the 2000's. It very well may be that NS attempted and failed to secure outside help, causing this GP68 proposal to not go anywhere.
And while a substantial portion of Norfolk Southern's ECO fleet were built with grant money, several actually haven't been.
The two GP22ECO's, the 12 GP59E's (An ECO unit without the name), and the six GP59ECO's were all built with private capital. It's the SD33ECO and GP33ECO fleets that have had their rebuilds partially funded by federal and state grant money.
oltmannd You buy new locomotives when they are a better deal than rebuilding what you already have. New locomotive ROI can come from fuel savings, maintenance savings and a reduction in fleet size.
A factor in the maintenace savings is what kind of warranty you can negotiate. 2 years used to be the standard but it was often negotiated to 3 years. Availability guarantees also count.
I found another document that showed this GP68 was to be an 8-710, not a 12.
bogie_engineer I found another document that showed this GP68 was to be an 8-710, not a 12. Dave
That would probably provide some significant fuel savings over the older roots-blown units (GP9, GP38-2, etc) that it would replace.
When did EMD start promoting their ECO repower line? I would think this proposal predates it by several years at least.
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