mandag 13. januar 2014
The first two links in this evolutionary tale come from in fact the V8: used in the portugeuse Switcher type locos and the NIR class 101 "thumper" class , where I had heard they were rated up at 1500 hp, but Wiki informs us 1350 the same as the iberian ones. At around the same time, the Aussies had successfully rated the v8 at 1760 hp in the KTM Class 22, which prove to be more reliable than both the Class 50 and the 101s of NIR.
The KTM class 22s were built in the early seventies in Aus' by EE / AEI. The clue here is that they used the CSVT mark III engine. It seems that this engine was not developed in Europe, where the major project was the metric RK instead.
Indeed then the Aussies were pretty keen on EE and developing locos as the power unit technology advanced, seen perfectly with the v 12 going from say the QR class 1270, 1300 (1540 and 1800 hp respc.) up to the 2350 a the same nominal bhp, and there is a quote of taking it to 2550hp ( far short however of the 3300 hp in the class 58) . The RK270 was then first installed in 47 601 at the time, in 1974 thus being built at the same time as the aussie MrkIIIs and probably sharing technology.
The Mrk III engine was the last used in Aus, I believe from EE and its later GEC who by then owned all of EE and subsidiaries including Rustons and those in Aus. It differed from the predecessors in having gear driven cams and a single stack cumulative exhaust route deliverying to a single, very much larger turbo charger. In the 2350 (at their full rating, not the Tasrail down throttelign to 1750) they sound most like the RK215 engines in fact, spluttering a bit and couging rather more than dubbing, but still recognisable as a thrashy v 12 from Rustons, as in fact is the v12 in the class 58 if you listen carefully or see the video from Tinsley depot, which included footage of them running around with their silencers removed.
The mark II is familiar in the class 37 and class 50, being at ratings of 167 bhp / cylinder in the 50 and 37 292 (2000hp experiment) and 145bhp. Meanwhile the aussies did the KTM at 220 bhp per each of her 8 cylinders, and the eventual 2350 at 195 bhp per cyclinder in her v 12. This compares to "47 601 " and the class 56 at 3250 hp overall, as 203 hp, and the 47 901 v 12 er then at the massive 275hp. Jumps of 30- 40 horse power then per cylinder in the early seventies and finally the sky was the limit for rustons and the smooth running v 12.
However now the missing gap in my mind, within the evolution from 10000/100001 , the humble class 08, the 20/40 rating and the UK ratings of the CSVT for traction use. A jump of 40hp per cylinder to the Mrk III and then a while went by before the class 58 came along. I sigh a little sigh of relief
The concept of tilting trains dates back some considerable time before even the APT- E (experimental, the single gas turbine version) made the light of day. 1970s technology was adequate for the APT-P , the prototype.
Only we didn't get a prototype, the first of it's type, we got six pre-production types, the class 370.
The crux of the matter lies in this very over ambition. Yes a gas turbine one off had been produced but it was a running laboratory using an already disfavoured power unit supply. Proof of concept was established. However what was needed was a single prototype of the APT-P and not a whole pre-production class.
Why not though, produce a further proof-of-commerciality if you like by having a viable class of APTs running actual passenger specials which reflected the belief in BR management that this was a faite accomplis, as before the HST and the Deltic and electrification had been. In the 1970s though and into the 1980s this arrogance would meet its match in an in patient, road-oriented Magaret Thatcher.
There are major issues with managing a project with six train sets: firstly you have a longer time for delivery and your overall budget is much bigger, despite being lower per unit than a single set. Secondly and most crucially, when you have something go wrong on one set which is serious, then you have to take all the other sets out of service (tests, PR visits and demonstration ADDEXs essentially) . Further to this you then have a very much larger burdon on resources and spare parts when you come to repair the problem or redesign the system.
The tilting system was somewhat problematic however all reports are that eventually this was solved to a level of reliability concordant with operational service. The braking system's design oversights would have been typical "punch list" items for the redesign between and APT- P single electric unit and any pre production run or actual production run (squadron)
Launching the train officially as an operational Faite Accomplis in a January was really just another example of project management not removing elements which could challenge the reliability of the project and its then key PR presentation.
This reflects on poor project management and too much power invested in decision making in BR in my opinion. Today if the railways were still public, or as with HST2 a public-private alliance, then the project would be subject to tender and also to an expert committee and nost likely the "quantum leap" from the APT-E to the electrified prototype would be managed by a single unit or in fact competing designs. Subsequently a fleet of pre-scale production models could have been established to introduce the trains such that the flagship services could be accelerated gradually and revenue returns on a 3 hour London-Glasgow, and shorter timings from Manchester, Liverpool and the West Midland towns on the WCML, services be assessed.
søndag 5. januar 2014
Not a lot of people know that most "syphon bashers" actually rated class 33s and hymeks. Given our mutual disrespect for the classes 31, 25 and 27 in particular it may come as a surprise. Type 3s though have to work for a living and have all proven to be capable of running type 4 diagrams. If in 1955 the folly of all the underpowered type 2s had been recognised then we may have had some interesting alternative type 3s.
A fact i did not know is that the 8LDA in the "shreddie" was actually rated at the same per cylinder as the humble class 26, another favourite of syphon bashers as variety on the far north and to annoy 27 bashers. This would mean a potential power output of just under 1700hp in the same locomotive.
How would then an RA5 version of the shreddie with a boiler as a competitor to the EE type 3? AIA configuration. Maybe he same gearing as a shreddie and also eth. Stretch a shreddie for the first of the class and then later orders into the 1960s are roof mounted head code box and a 25 / lion body style? Up at maybe 1685 hp. Given the loco had different field diversion speeds then it could have been a better alternative to the syphon for those draggy 40-50 mph diagrams so loathed by drivers. I can imagine this machine becoming a passenger dedicated dual heat affaire in the late 1970s and working a pile of regional and cross country semi fasts and standing in for duffs on expresses. Scr would have been delighted with them for whl, highland and far north, fife circuit, perth routes and south of glasgow central.
What though if SR had decided on a dual mode version, on an AIA format with a boiler for non ETH through trains. I rather fancy then a class 34 and 78. Dual mode deltic with a single PU and 25kv overhead where the other engine used to be?
Another tantalus a diesel electric hymek in co co ? That could have lead to a nice class with uprating possibility for ETH. Or of they had put a decent ventura or valenta in the "Goil" class 31 at over 1600. No matter, there should have been space for the CSVT in there and that would have been then a greater loco than the rather pedestrian accelerating 31.
If Bayer & Peacock were in there then why not NBL ? An MAN v16 or a smaller twin engine type three? A scottish hymek, mini warship completely capable on the route times of the ScR in DE version for north of the border and as an oil slosher.
Finally back to a light weight bobo single engined deltic type 3 to 4. The trouble of the baby deltic was that it was built on a traditional heavy frame chassis rather than the tubular and space frame deltic
fredag 3. januar 2014
As I predicted some years ago, dual mode locomotives would become more prominent in r and d, and emerge. They are now the next big thing with rail head transport becoming more cost effective as companies produce scale to compete and road haulage becomes more expensive and slower.
Environmental Politics and economics play as large a part now in shaping the locomotive species as they did in 1955. Now with the emissions vogue for mid to high speed diesel power units things have changed. This means smaller space for the PU more space for scrubbing, but also the possibility for a return to the electro diesel and of course multi engine.
In the 1950's twin engines were chosen due to high power output relative to the available hydraulic and DE transmission systems which were then limited to about 2000 kw at a push in Germany, and for UK budgets and loading gauges, little over 1000 kw.
EE worked this one out in relation to getting "3000hp under the bonnet" for sustained 100mph express running, and the WR dedicated to light weight DH power by the early 1950s following the early adventures into heavier 1500-2000hp single engine units. Brush followed suite with the ugly duckling "Hawk" , which could have proven a swan in terms of performance at up to 3000hp compared to the castrated class 47. Even in the ashes of the deltic rose the phoenix of the uk's most successful passenger train, the HST with its high speed Valentas.
First the anglo belgian powered diesel hydraulic to raise eyebrows with its wheel slip free creep lifting enormous coal trains. Then we noticed the reverse, with old locomotives being refurbed sometimes reengined and sent out with new, smaller operators. Suddenly after the predominance of the GM/EMD v 12 two stroke mid speed whiner was under threat by the fragmentation of the industry and the nervousness over buying any loco which may be legislated out of traction wijthin its payback time
Now Bombardier shock us all with not two but four bustly little 750bhp units. This is a modular Traxx loco and they admit to hedging their bets by having a plan for battery replacing one or more power units.
This brings a lot of questions up. Firstly how often do you run on less than all units? Well deltics often ran the aberdeen route north of edinburgh on one unit, pairs of thirty sevens were often switched leading to control only. Another intention from the DB V200, the deltics to the HST was to allow for failure redundancy. This was often the case allowing the service to be completed even on time for the slacker diagrams. DMUs are generally
Secondly then you have all this on and off, which is bad news however. Larger diesel power units are high compression, long stroke and dual air charged, and the higher speed engines before in time did not respond to idle start stop in traffic.
Thirdly how much power do u really need to start a train? This is a major plus point for the next generation electro diesels which may only need to crawl from the rail head to the overhead AC wires. Here you can haul a thousand tonnes with one of those wee units in the new traxx without a gradient to ply. A class 37 first series once hauled a 1600 tonne dead train in south wales, the lower geared RA 7 version would have maybe done 2000 all be it at less than 20mph.
The next thing is back to longevity versus life cycle. I think it is pretty ridiculous to impose stingent and eventually zero emissions to frieght and express passenger given how many car and lorry journeys they replace. However the road lobby and the percieved need to have clear emissions limits on larger power units across the board means that some locos will maybe only have a 20 years life span and may be reengined or dual moded within that.
Historically rail operators have always tried to run powerunits at longer than manufacturers recommended service intervals and with rarer locomotives like the soveriegn class 60, they attempted to reduce intermidiary "examinations" as they call inspections and filter changes. Given low sales of this new traxx four PU or any other high speed engined loco, then they do not acheive a redundancy in servicing ie there are not enough powerunits spare or ready serviced to feed the small fleet. The pluss side is standard servicing at non rail depots though ,and if it comes to it, a cheaper replacement cost than a single v16 mid or high speed unit.
The future is a bit like 1955 if you ask me , a fragmented approach with some locos.trying hard to fix a political problem, orders being small and a some specialised to country or purpose, deisel electric or hydraulic , flirts with electro diesel, battery and alternatjive combustion. Fifth generation locos start to sound a lot like first generation fifties ones.