46257 City of Salford

Evening All

I hope you will let this thread remain in this category as it features just 1 loco on a rather sad day

46257 City of Salford inside Preston MPD 30/9/64 on the day it was withdrawn
http://railway-photography.smugmug.com/LMSSteam/Stanier-Locomotives/Princess-Coronation-Class/Princess-Coronation-Pre-1968/46251-46257/i-Wt9n8vD
one for the history books!!


Neil

 

Agreed, roller bearings? BR standard trailing truck.
Is that a mileometer on the leading tender axle box?

 

Also of interest because - with 46257 - they were built specifically for comparison with Derby's pair of diesels 10000 / 1 and not simply as additional members of a particular locomotive class .

 

I didn't know that but I wouldnt have thought anything could have beaten a Duchess for sheer power ,I mean do we really know what 46233 can do when given the gun?

 

The plan to compare with the two diesels never really happened as 6256/7 simply slotted into the normal pacific diagrams. 10000/10001, by the way, were singly rated as equal to and judged against a Black Five; for comparison with a pacific, the diesels were worked together in tandem, not singly. There are many photos of the pair on, for instance, the Royal Scot.

The object on the bogie is indeed a milometer, as it was hoped to get 100,000 miles per year from these two engines and an accurate record was needed. It never happened. In practice, despite the bearings, 6256/7 were little if any better than the plain bearing engines as far as mileage went, again a symptom of their diagramming, and 6257 in particular was actually poor, spending a lot of time in works for attention.

 

Fair point but I didn't expand on this because my main point was that - in one respect - either of the Ivatt pair had valid historical reasons for preservation.

As you rightly note the "comparison" never took place because of many factors involving the diesel locomotives themselves - especially regarding train-heating. In winter they were operated on Willesden freight diagrams with one loco compared to a Black 5 in which context they achieved that standard and more. In summer (when no heat was needed) the pair operated both singly (proving to be the equivalent of a Class 6 but mid-way between a Jubilee and a Royal Scot on Blackpool services) and in multiple (proving to be the equivalent of a Duchess BUT - more importantly - capable of working a round Euston - Glasgow trip of 800 miles in one day).

A further point about the comparison, however, was that the comparison wasn't just about haulage but also the construction, operating and maintenance costs and it was these latter items - important as they were - that were never followed through to the publication of comparative costs as was later undertaken for the Electric v Hydraulic transmission decisions that were made in the 1960s.

A question of interest : you state "in tandem" meaning a driver on each loco but surely these operated "in multiple" meaning one driver operating both locos ?

 

Weren't they fitted with steam heat boilers?

 

Another thing BR got wrong, anyone who rates a 47 above a 52 needs their head examined.

 

In the photo above it looks alot like a US Delta Trailing truck.

 

Which is indeed what I meant.

The two diesels weighed in at about 127.5 tons each, which equates quite nicely with a Black 'un with tender, but the two in tandem out-weigh the pacific by about 90 tons. Their maximum power outputs also equated more or less with that of the steam locos, but the diesels' advantage was that they could deliver higher continuous outputs, hence their abilities towards the 5XP performances.

Their turn-around time was of course better than the steam engines', due to the labour intensive nature of steam engine servicing, which was never really addressed in this country. But in practice, they would, like all early diesels, work within the steam diagrams so this would show up only if special arrangements were made.

 

The trucks were changed early on on both locos. You can see in the photos of the new locos that the arms of the first trucks were of an I or channel section, but both locos subsequently had what appears to be a more conventional cast delta truck.

 

6256/7 were supposed to be harder riding than the others, all down to spring rates no doubt. Here's a question I bet some of you know - what part of 6256/7's design went into the rebuilt Bullied Pacific's?

Dave

 

Reverser?

 

Spot on Buseng ☺ I think it was John Harvey from MNLPS. who told me that many moons ago.

What a shame no-one saved 46256 in 1964 when it was offered for £2400.

Dave

 

Cheers, it was only a guess because the angled shaft looked very similar. I presume some of the BR Standards are very similar.
£2400! Christ, people paid more than that for Barry wrecks.