Double heading of diesel & electric freight trains

[Gibbo675]

Jim

 

I'm still not totally sure I understand how the pivots steer the axle boxes - any chance of a sketch?

 

The bit that I really don't get is that, to achieve a radial action, the rods/bars would need to get shorter/longer ..... are there slots or something to give dead motion?

 

The drawing I have is a side elevation, so even when I find it, I now don't think it will help.

 

Kevin

Hi Kevin,

 

Does this help,

 

 

As you might appreciate this is a schematic diagram.

 

If you put the pivots of the links at the cannon box attachment inboard of the pivot points on the bogie then the axle will swing perpendicular to the tangent of the curve traversed. Should you reverse the arrangement then the poor old 1CO-CO1's pony wheels would look like a ponderous speedway bike. I should guess that the position and length of the pivot links will be designed to a theoretical point somewhere around bogie pivot centre or the centre line of the bogies fixed wheel base.

 

The swing links of steam loco truck bogies work in exactly the same way except they are in the vertical plane and use the resistance of the suspension springs above the axle boxes to effect centering forces

 

Try it with a set of compasses.

 

Gibbo.

[Nearholmer]

I get it.

 

Many thanks.

 

K

[jim.snowdon]

Thanks, Gibbo. That saved me drawing it.

 

I had been looking for a photograph, unsuccessfully so far, that I had taken after using the same arrangement for the radial axle on an 0 gauge LNWR 0-8-2.

 

Jim

[Gibbo675]

Thanks, Gibbo. That saved me drawing it.

 

I had been looking for a photograph, unsuccessfully so far, that I had taken after using the same arrangement for the radial axle on an 0 gauge LNWR 0-8-2.

 

Jim

Hi Jim,

 

I only know what they look like for in a past life I have welded frame cracks and re-riveted after replacing Huck bolts on the CFPS locos at Bury.

 

Gibbo.

[The Stationmaster]

Thank you for all the replies so far, it’s made a lot more sense of things.

 

 

What a fascinating read! Thank you for sharing these anecdotes.

 

However, one would have thought that 2x 37 would easily outpower a single 56, how much extra tonnage were the pair of 37s moving?

 

Somewhere I've got a copy of the paper I gave at the Inst MechE 'Heavy Haul' symposium back in the early 1990s.  I was invited to present a paper showing the operator's viewpoint of what had happened as we moved towards more powerful locos and much heavier trains - the symposium was sponsored by Foster Yeoman and GM, I f shall have to try to delve it out as it shows some interesting comparisons from the 1000s onwards.

 

The interesting and awkward feature was that as power had increased and loads had grown so speeds, particularly on rising gradients, had generally tended to fall and this had become as more marked problem as speed differentials between passenger and freight trains had increased.  For example a Class 59 taking a full load (5,000 tons trailing) off Westbury towards the Berks & Hants only had sufficient margin to get to Woodborough loop, 17 miles away, if a following HST running non stop had not left Taunton - which is 33 miles from Westbury.  Fortunately even back in the early days there was not much in the way of really heavy trains running eastwards when the passenger service was operating but it did show that ability to shift load wasn't the only factor.

[USRailFan]

90s draw too much current to work as a pair on the GEML. That's why they are paired up on the WCML as the overhead lines are beefed up a bit more. The double headed freightliner class 47 & when they used 37s were basically down to running at class 4 speeds with the maximum trailing load.

 

Were there 47s that could be ran in multiple w/each other? Or did they always have to have two drivers (one in each loco)?

[USRailFan]

For info, 2x86 are used on the Anglo-Scottish liners because they're able to beat Shap and Beattock at a velocity that diesels can only dream of, same with Skodas on the Russell jobs, albeit isolated TMs here and there.

 

Class 86/87 were arguably BR's best investment ever, a fact that their current owners seem to agree with, both in the UK and Bulgaria.

Pity the 87s had to go abroad for this to be realised, but hey!

From what I'm hearing lately, we can expect 86s to outlive all of us. G&W aren't daft, the company own them rather than lease them so I'd be very surprised if these venerable and capable old girls are binned anytime soon.

 

Won't there be a number of 90s available within a year or two, then Anglia get their Flirt sets for the GE?

[Fat Controller]

Were there 47s that could be ran in multiple w/each other? Or did they always have to have two drivers (one in each loco)?

There were a handful in later days, I believe; otherwise they always operated in tandem, rather than multiple.

[Steadfast]

The giveaway of 47s that are able to operate in multi (besides a handful of early DRS conversions) is the fitting of an orange socket on the front, between the marker lights on what was the headcode panel originally. I think it was Railfreight Distribution that did the fitting, so late 1980s, early 1990s

 

Jo

[russ p]

At first the DRS ones had DRSs version of blue star so could work with 37s and 20s

They often used to trip the control circuit breakers so were modified to RfD standard green spot

[Suzie]

It looks like there are some power supply improvements going in at Boreham so will we see double headed 90s on the Great Eastern soon too?

[Fat Controller]

The giveaway of 47s that are able to operate in multi (besides a handful of early DRS conversions) is the fitting of an orange socket on the front, between the marker lights on what was the headcode panel originally. I think it was Railfreight Distribution that did the fitting, so late 1980s, early 1990s

 

Jo

I think a few were converted for the Swindon- Longbridge trains, then further conversions were done immediately prior to the opening of the Channel Tunnel.

[Zomboid]

It looks like there are some power supply improvements going in at Boreham so will we see double headed 90s on the Great Eastern soon too?

It's an upgrade to the feeder station there. There's a lot of new passenger equipment coming for the GE soon, so it could be unrelated.

[Clive Mortimore]

Now I always thought double heading was to give trainspotters two numbers per train not one, especially if both were cops. :locomotive: