Railroad Forums 

  • EMD Export Locomotives

  • Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.
Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.

Moderator: GOLDEN-ARM

 #1344035  by Pneudyne
 
I have looked for information on the EMD G6, as a catalogued-but-not-built model. All I have found so far is a brief mention at the end of an article on the EMD G12 in DRT for 1957 June, attached.
DRT 195706 p.236 EMD G6 Reference.jpg
I’d take that as evidence that at one time the G6 as such was in the EMD catalogue, although I suspect that it may have gone by the time that article was published. DRT could well have been using “stale” information.

It does not confirm that the G6 used the same frame and body as the G12 and G8, although I think it creates a circumstantial case, given that it is included with the G12 and G8 as one of three standard models, and that these two did share the same frame and body. Assuming that was the case, and that the rear face of the 6-567 was in the same relative position as for the G12 and G8 engines, then there would have been quite a bit of “white space” between the back of the driving cab and the air compressor.

The Clyde-GM G6B was a lot different to the original G, and seems to have been derived more from the GL8, particularly the lengthened A1A-A1A variant built for Brasil, drawing available here: http://vfco.brazilia.jor.br/diesel/sr6/03-GL8-a1a.shtml" onclick="window.open(this.href);return false;.

I have also found a layout drawing of the G16, attached, which shows it to have had a similar, but larger cooling group to the G12.
RT 195904 p.42.jpg
Now heading towards the trivia, as far as I know New Zealand Railways (NZR) was the only operator to receive both the EMD/GMD and Clyde-GM versions of the G12. Its first 30, delivered in 1955, were split between EMD and GMD, and were followed by 10 from Clyde-GM in 1957. Apparently, at the time, Clyde-GM offered quicker delivery albeit at a higher price, but with less of a US dollar component, important back then when US dollars were very short in the Sterling area. The Clyde-GM batch were the first to NZR fitted with cast trucks, which allowed operation at up to the line speed limit of 55 mile/h (although allegedly their D19 motors did not much like fast running), whereas the first batch with fabricated trucks had been restricted to 35 mile/h. Subsequent deliveries, all from GMD and from 1961 onwards, had Dofasco cast trucks.

The Clyde-GM batch had 6SL brakes, to match the initial EMD/GMD batch. On the face of it, that was nothing unusual, except that the Clyde-GM standard fitment was A7EL, then the Australasian standard. So from the Clyde-GM perspective, 6SL was a special fitment. A7EL, was, in Australasian terminology, a 4-pipe system (2-pipe independent in US terminology, I think). NZR had in fact adopted the A7EL as its standard for mainline electric and diesel locomotives in the late 1930s. I suspect, but don’t know for sure that 6SL - thn the standard fitemnt on the G12 - was accepted for the initial G12 fleet because it was needed in a huge hurry, and stopping to fit A7EL, possibly requiring some parts from Australia, would have incurred an unacceptable delay. Anyway, that event established the pattern. With its 1961 G12 delivery, NZR switched to 26L, being the first operator outside of North America to use this system. For backward compatibility with 6SL, it chose the (scarcer, I think) 3-pipe version of the 26L. But it got more complicated. The last one of its 17-strong G8 fleet of 1965-66 was fitted with the 4-pipe universal version of the 26L, for backward compatibility not only with 3-pipe 26L and 6SL, but also with non-American (or should it be unAmerican) locomotives that had A7EL or 26L 4-pipe non-universal braking systems. It also had an MU interface that allowed operation with these other locomotives, which had 110-volt control systems and 10-notch throttles.

In Australia the braking progression was to B7EL, with self-lapping independent, in 1959, then to 4-pipe non-universal 26L starting around 1966, although with a slowish initial uptake. Anecdotally it was said that Westinghouse Australasia, with its near-monopoly, was in no hurry to move to 26L.

Cheers,
 #1344760  by obsessed railfan
 
Pneudyne wrote: EMD placed a six-page advertisement in the trade journal “Diesel Railway Traction” for 1958 November
First, I have to say this is a great thread, I am very interested in EMD export locomotives.

I also have to say, I find it interesting that the 6 page ad from 1958 shows the GL8 available at that time, even though the first production GL8's weren't built until 1960...which were A1A's for Taiwan Railway Administration.

Even though the drawings in the ad don't depict it, most EMD export switchers were setup to operate with the cab end designated as the front, while domestic switchers here have the long hood end designated at the front.
 #1344811  by Pneudyne
 
The shaping of the cab end-plates of the GA8 and GL8 certainly created the impression that they were intended to look presentable when running cab first. GE didn’t do that with its end-cab models until the mid-1960s.

The GA12 actually appeared as running cab forward in this EMD advertisement:
DRT 196109 p.51.jpg


The Taiwan A1A-A1A version of the GL8 was, as far as I know, similar to the Bangladesh (East Pakistan) version. The truck centre spacing had been reduced to shoe-horn the 10’6” wheelbase A1A trucks under the B-B frame.
DRT 196305 p.21.jpg

But Brasil had a different version, retaining the same truck centres as the B-B but with an extended frame.
GL8 A1A-A1A Brasil Version.gif


Cheers,
 #1346221  by Pneudyne
 
Quite unusual amongst the EMD export models were those with longitudinal frame-mounted motors and shaft drives. The GA8, already mentioned upthread, was a catalogued model. The GA12 and GA12C were apparently specials, built only for India.

An article in “Railway Gazette” for 1965 March 19 provided a good description of all three models, including the drive arrangements. The first three pages thereof are attached.
RG 19650319 p.221.jpg
RG 19650319 p.222.jpg
RG 19650319 p.223.jpg

Cheers,
 #1346222  by Pneudyne
 
Here are the final two pages.
RG 19650319 p.224.jpg
RG 19650319 p.228.jpg
The GA12 was of 1-B-B-1 wheel arrangement, but with an unusual layout in respect of the pilot trucks. Normally such would be both pivoted and loaded from the main truck frame, as for example was the case with the 1-C trucks recently pictured in the “Alco Export Locomotives” and “GE Export Diesels” thread.

In the EMD case though, the pilot trucks were pivoted from the main truck frame, just ahead of the latter’s centre pivot. But they were loaded directly from the locomotive frame. Possibly this arrangement was chosen to help maintain the simplicity of the main trucks, which followed the freight car pattern established with the GA8. It seems unlikely that the pilot trucks did or even could exert much lateral guiding force on the main trucks. Rather the pads that took the load from the locomotive frame would have provided a measure of lateral resistance.

The 1-B-B-1 wheel arrangement was quite rare in the diesel locomotive world. Apart from the 30 EMD GA12, I am aware of only 20 other examples (which had conventional truck design and drive).

Cheers,
 #1346414  by v8interceptor
 
Pneudyne wrote:Here are the final two pages.
RG 19650319 p.224.jpg
RG 19650319 p.228.jpg


The 1-B-B-1 wheel arrangement was quite rare in the diesel locomotive world. Apart from the 30 EMD GA12, I am aware of only 20 other examples (which had conventional truck design and drive).

Cheers,
Not to get off topic but EMD along with licensee partner DLW have produced a significant number of WDP-4 locomotives; a variant of the GT46PAC model, for Indian railways using that truck arrangement.
EMD also built 20 SD70Ace variants (SD70AceP-4) for BNSF using that wheel arrangement.
 #1346506  by Pneudyne
 
Not at all off-topic, as the GT46PAC is an export model, and export models are I think better reviewed and understood in the context of parallel domestic market developments.

I was vaguely under the impression that these models, the EMD GT46PAC and the SD70ACeP-4, had the B1-1B wheel arrangement, essentially using three-axle trucks with motors on the outer and centre axles only. But I’ll now need to recheck that.

B1-1B could be seen as a variation on the A1A-A1A theme, simply with a different disposition of the motors. One may wonder why it did not make an earlier appearance, say in the 1950s or 1960s. But the A1A truck was established quite early on, and perhaps its symmetry appealed. In terms of track loading, it may not always have been ideal, though. For example, where tapered axle loading was adopted for C-C locomotives, the truck centre axle had a higher loading than the two outer axles, this calculated to provide bending moment relief. Against this, A1A trucks look to have been the obverse, often with a more lightly loaded centre axle, which also lacked the burden of an axle-hung motor.

Nevertheless, B1-1B was at least considered in the past, even if not implemented at the time. I have some documents for a mid-1960s English Electric proposal for a small road-switcher (about the same size as an Alco DL-531, although lighter) that was offered with C-C, 1B-B1, A1A-A1A, or B1-1B running gear, all using the same three-axle truck frames. It was built only as a C-C, though.

Cheers,
 #1348132  by Pneudyne
 
Another unusual EMD export design was the TT12, built by licensee Henschel for Ghana in the late 1950s.

This was a Cape gauge double-cab C-C unit with streamlined ends, but with a verandah-type construction between the cabs, reminiscent of the second series of UP 4500 hp GTELs.

An outline drawing of the TT12 is shown in this 1958 Henschel advertisement.
DRT 195810 p.17.jpg

I guess that in terms of equipment, it was much like the GR12. It looks to have had the same style of flexicoil trucks as that model

Cheers,
 #1348135  by Pneudyne
 
The second locomotive illustrated in that Henschel advertisement, built for South African Railways, (SAR) looks like one of its own diesel-hydraulic designs of the period, not connected with EMD and so out- of-scope here. Not quite, though, as it was fitted with a pair of EMD 6-567 engines. On that basis I think it just qualifies for inclusion here, so I have attached the DRT article about it.
DRT 195904 p.161.jpg
DRT 195904 p.162.jpg

Almost predictably, it was not a successful design, and one wonders what possessed SAR to buy it at a time when it saw GE diesel-electrics as its best choice for dieselization, and when it was said to have preferred four-stroke rather than two-stroke engines. Possibly it was a crumb thrown to Henschel, who had been a major supplier of steam locomotives to SAR, and was no doubt looking for a share of the SAR diesel business. Given that Henschel also had access to the EMD engines, perhaps this was seen as a better choice, even though not of a preferred type, than one of the German high-speed engines of the era.

Cheers,
 #1349850  by obsessed railfan
 
Does anyone know where the bell is mounted on G12's and other early export locomotives? Obviously horn and bell placement on EMD export locomotives can vary by railroad, as is the case with domestic EMD locomotives. However, the bell seems to be hidden somewhere on every early export model I have seen. On later export models such as the G22, the bell can be seen and is usually frame mounted similar to domestic EMD products.
 #1411013  by Pneudyne
 
Here is some more information on the Henschel-EMD TT12 model, built by Henschel for Ghana, and mentioned upthread.
Henschel-EMD TT12 Sideview.jpg
Henschel-EMD TT12 Line Diagram.gif
This was seen by Henschel as a tropical model, which probably explains its TT12 designation (I imagine double T because it had two cabs). EMD also referred to it as a J12CU, but I suspect that designation might have been applied retrospectively once the “J” series was started.
EMD Product Reference Data Export 1986 January p.30.gif
Cheers,
 #1411015  by Pneudyne
 
The TT12 trucks were an interesting variation on the EMD flexicoil theme. Because the design was height-restricted, a very thin bolster was required. In this the centre-plate provided location only, with the vertical load transferred by loading pads at the four corners of the bolster.
Henschel-EMD Truck.jpg
Henschel-EMD Bolster.jpg
Presumably the choice of equalized primary suspension was also a result of the height restriction, in that there might not have been room to mount the springs above the axle boxes per normal EMD practice.

The use of underslung equalizer bars might also have stemmed from the height restrictions. Inside drop equalizers could have required additional clearance above the axleboxes, and outside drop equalizers might have fouled the available lateral clearance. Underslung equalizers seem to be less common than the drop type, and the major user was English Electric. Though Henschel again used underslung equalizers on the B trucks of the Egyptian AA12 model. The equalizer bars also had pin-jointed ends, something typically reserved for light axle load locomotives where any friction that might interfere with the equalization needs to be avoided. Another example of pin-jointed equalizer bar ends (inner ends anyway) was found on the GSC 1-C trucks used under the South African GE U18C1 fleet.

One may trace what appear to be some interesting “connections” here, although they might well be just happenstance. Elsewhere it has been noted that the British LMS prototypes #10000/1 had C trucks that were reputedly inspired by the EMD-Blomberg A1A design used under the E model passenger locomotives. Originally these prototypes were to have an A1A-A1A wheel arrangement, the change to C-C being made quite late in the design process. Allowing adequate clearance for the centre traction motor required a very thin, slightly arched bolster that was used for location, with the load being carried by four corner pads. So one might observe that the influence trail went from EMD to LMS and then back to EMD, although it could simply be that unconnected groups in different places at different times came up with the same answer. English Electric (EE) was influenced by the LMS bolster design for its SB-gauge C trucks, starting with the prototype Deltic in 1955. It adopted underslung equalizer bars to minimize unsprung weight, and also made the bolster frame hollow to act as a conduit for traction motor cooling air. Ghana Railways bought a fleet of EE C-C locomotives in 1969-70. Characteristically these had trucks with underslung equalizing beams, but they also had pin-jointed beam ends, a feature not normally used by EE. Perhaps that was specified by Ghana Railways basis its TT12 experience.
Henschel-EMD Truck Frame.jpg
The welded, but shaped truck frame of the TT12 was typical of German practice of the time, and possibly it was informed by earlier Swiss work. I think that the German view was that with good design and construction, such trucks could match cast framed trucks for durability and with reduced weight. Possibly though German industry could not easily produce large cast truck frames. In Europe at the time, the two often-mentioned suppliers of cast truck frames were English Steel Castings (ESC) in the UK, a Commonwealth licensee, and Henricot in Belgium.

Cheers,
 #1411029  by Pneudyne
 
pjw1967 wrote:I guess this might count as an export model built under license with the 567 prime mover.

http://www.railpictures.net/viewphoto.p ... 88&nseq=79" onclick="window.open(this.href);return false;

It looks to be very similar to those built by Henschel for Swedish railways (SJ).
DRT 195907 p.280.gif
DRT 195907 p.281.gif
DRT 195907 p.282.gif
No surprise that SJ chose the Krupp-Lysholm transmission.


Cheers,
 #1412107  by Pneudyne
 
Another Henschel-EMD export model was the AA16 double-cab unit supplied to Egypt from 1960. Unlike the preceding KK16, which had a pair of 8-567C engines, the AA16 was conventional, with a single 16-567 engine, although still with an A1A-A1A wheel arrangement.
Henschel-EMD AA16 for Egypt.jpg
Henschel-EMD AA16 for Egypt - Layout.jpg
Some information on the KK16 was provided in the “History of the E-Unit” thread: viewtopic.php?f=6&t=96314" onclick="window.open(this.href);return false;.

With the KK16, Egyptian Railways (ER) had wanted two engines and as much commonality with its contemporary EMD G8 fleet as possible. By the time the AA16 was ordered, ER had diversified somewhat, and had also ordered the EMD G12 and G16 models as well as the G8. So that AA16 would have had quite a bit of commonality with the G16 (and similarly the AA12 with the G12).

The AA16 used “normal” variant of Henschel’s welded-frame version of the EMD Flexicoil three-axle truck, which may be compared with the “flattened” version used under the TT12, shown upthread.
Henschel-EMD AA16 for Egypt - Flexicoil Truck.jpg
Cheers,