Oil Firing

From what I've read Stratford were, once again, streets ahead of the others, having a 'small' coal fired grate which was lit with the 'rag on a stick' and kept burning, thus being a form of pilot light.

 

Or possibly not. The GER had oil fired T19 locos around 1900.

 

Hydraulic transmission is still widely used I believe in DMUs and industrials but I guess you are referring to mainline locos. At the time hydraulic transmission (which generally seems to include the ones with automatic gearboxes and fluid couplings) looked pretty attractive at c. 80t for a Warship cf. 130t+ for a Peak or Class 40.

 

The SECR system (which Holcroftvsaid was based on the Derby system) had the same, the reason given by Holcroft being to maintain a more even temperature in the back corners of the box when the oil supply was shut off.

Tom

 

Umm, whatever the technical merits, a solution that requires the operator to keep a coal storage and distribution infrastructure alongside the new oil one is a lot less than ideal from the POV of logistics.

 

I guess it depends on the rationale for oil firing. Reading Holcroft and his description of the 1921 (SECR) and 1926 (SR) trials, it seems they were looking for an insurance policy if coal supplies were interrupted by strikes. So the overriding requirement was something that could be fitted quickly and cheaply without substantial changes to the existing locos; and where - even in a strike - you would have some coal supplies available and all the infrastructure for coal handling. So they did a kind of hybrid oil / coal system. There are figures in his book; I think they were getting about 80% of the energy from oil and 20% from coal. He also noted that more or less any old rubbish coal was sufficient. As things turned out, the 1926 general strike collapsed and they never needed to roll out the scheme fully.

If your requirement is to make a strategic switch from coal to oil, then you would design things differently, but in so doing may also require more substantial changes to the locomotive firebox (and ancillaries) design.

Tom

 

Another thing with coal was pilfering Somene once said to me that he wondered how much of coal leaving a East midland coal mine to one of the larger loco sheds, in a say a 13 ton wagons went into a loco firebox .Pilvering was known to be quiet high,signal boxes were suplied off the tender of the local pickup goods, as was brake vans for the guards fire.Coal reserves kept at loco shed were white washes top and sides so if any was stollen it could be noticed.None of that if oil was used.

 

But the GER never did and as far as I can tell never intended to make a full oil-firing changeover, even on a local level, peaking at around 60 locomotives in the mid 1890s according to the GER Society. A significant reason for doing it at all was to burn the waste from their gas plant (having been fined for discharging it into the Lea); as usage outstripped the supply available from this source (with introduction of carriage electric lighting helping to reduce the amount of gas needed), having to buy oil to supplement the waste oil made the economics a lot less attractive and it was gradually phased out.

It was however pretty successful in a technical sense. In addition to conversions and some of the T19 class, as far as I can tell some fraction of the original S46 round-top Clauds were built oil-fired, and I have seen their strong early performance as oil burners cited as a factor in the good reputation of the class.

 

Not forgetting the Class 14 s which had a very short live in B R service.

 

Stratford wasn't running exclusively on oil fired locomotives, so coal storage/distribution infrastructure wasn't a problem.