LMS 2-8-0 tank ?

[PenrithBeacon]

3 hours ago, kevinlms said:

The fact Big Bertha was in use from 1919 to 1956, suggests that it must have been considered as better than useless. Given the LMS policy of scrapping many small classes of locomotives and plenty of 0-6-0Ts around, indicates that it was useful enough to keep in service.

Never a brilliant loco but good enough, until it needed a major rebuild. IIRC there was a spare boiler to reduce repair times in the workshops at Derby.

Didn't say it was useless!

[The Johnster]

9 hours ago, TheSignalEngineer said:

Lickey makes interesting reading with regard to big engine design. Bertha was reputed in some sources as having originally being a design to cut double heading of coal trains on the Midland Main Line, the job eventually done by the Garratts. It was slow and heavy, and the crossover piston valve design from the outside valves to the inside cylinders would not give a good steam flow. It also had to go through most points at walking pace as it was too rigid. 

Lickey was found to be ideal for it as it was a ten to fifteen minute low speed slog on straight track usually twice per hour, so plenty of recovery time for steam raising. 

Interestingly when the WR took over the line in the mid 1950s they tried their 2-8-0T on the bank but it was not as good as a pair of Jintys.

 

I can't see it ever being any use on Toton-Cricklewood coal drags with those massive cylinders, which are going to empty even that big boiler in a very short distance if the loco is opened up for hard work, and it looks to have been always designed with the Lickey in mind.  Even at the low speed of the mineral trains riding would have been diabolical.  The rigidity that made caution necessary over yard points suggests that the intention was to get as much of the grunt down on to the rail as possible, again suggesting a banker.  Smaller, lower set, cylinders and arguably a leading pony truck were what you wanted for the Midland's mineral traffic, but as we all know they were awash with 0-6-0s and didn't mind the double heading, or at least they never seemed to put any serious effort into designing a big engine for this work.

 

Single 42xx TE 31,450; 2x Jinty 41,670, which makes the '1.5 JInty' rating about right.

[FoxUnpopuli]

Not sure if the LMS Garratts banked the Lickey, although they did run trains up it.  The U1 did bank, and was converted to oil, but wasn't well regarded for a variety of reasons - fairly or unfairly.

 

Good discussion.  No doubt the 9F was the successor to Big Bertha's 'big gun' role, but I like to think what would have happened had the LMS required a replacement sooner.

 

This discussion about coal storage is interesting, but if a big Stanier tender had 9 tonnes, and the tank described had 6 tonnes...  The Jinties managed it with a little over 2 tonnes in the back...  presumably they kept stocked from staithes at the bottom of the hill, right?

 

 

 

 

 

 

[TheSignalEngineer]

20 minutes ago, FoxUnpopuli said:

The Jinties managed it with a little over 2 tonnes in the back...  presumably they kept stocked from staithes at the bottom of the hill, right

Bankers regularly stood in the siding by the coal stage between trips

 The 9F had a specially modified tender side to make it easier to shovel coal in.

[Dave Hunt]

From some research I did for articles in LMS Journal, the 0-10-0 was specifically designed as a Lickey banker.

 

Even though the Midland’s bigger tank engines were stationed at Bromsgrove from 1900, many trains in the Edwardian era still needed two or more of them to assist in the climb to Blackwell. This was uneconomical in several ways: four men had to be employed for a start and the coal consumption of two engines tended to be greater than that of a single locomotive twice the power. The first point could be addressed by having just one man on each of two bankers coupled together, only one of whom need be qualified as a driver, which was merely an extrapolation of the principle established with motor trains and was suggested by the Traffic Department. The second needed a new design concept, which was favoured by the Locomotive Department, and after due consideration this was the course of action taken. From about 1910, schemes were put forward by the Derby Locomotive Drawing Office for several different concepts including an 0-10-0T to DS 1543, a 2-6-4T to DS1553, a 2-10-0T to DS 1653, two 2-6-6-2T Garratts to DS 1677 and DS 1703, an 0-6-6-0 back tank to DS1737, and another 0-10-0 to DS 1785.

 

The proposals mainly concerned tank engines of various kinds for the obvious reason that this placed all, or most, of the weight on the coupled wheels. I don't have details of the 0-10-0T to DS 1543 but anecdotal evidence suggests that it was the basis of the DS 1785 scheme that was eventually developed into the locomotive actually built. The maximum axle loading proposed for any of the tank engines was 17 tons 18 cwt, which was 2 cwt less than the heavy goods tank engines. This makes the common story of the design being altered to a tender engine so that the axle loading could be brought within acceptable limits seem unlikely. Even taking 2290 as built, it could have been given side tanks and a bunker large enough to carry sufficient supplies for its role without exceeding 18tons on any axle. It is possible that the addition of even a small bunker would have given problems with overthrow on curves but that is merely supposition. Whatever the reason, the engine was built with less than 74 tons on the coupled wheels compared with up to 105 tons on the Garratt schemes, 94 tons on the other tank engine proposals, and 97 tons for a pair of heavy goods 0-6-0 tanks. As well as limiting its adhesive weight, giving the banker a tender meant that it had to drag between about 25 and 31 tons of dead weight behind it on every trip depending on the amount of coal and water carried, which increased its coal consumption. Since the men who ran the Midland Railway were not idiots there were obviously good reasons for the decision but I don’t know what they were.

 

Hope this is of interest.

 

Dave

 

Edited November 2, 2019 by Dave Hunt

[FoxUnpopuli]

More interesting information, thank you!

[kevinlms]

5 hours ago, PenrithBeacon said:

Didn't say it was useless!

I didn't mean you did. I was trying to put the point across, that Big Bertha was not brilliant at it's job and not a disaster either, otherwise it would have gone long before.

The fact that the Midland apparently never considered building a 2nd one (surely there was the traffic for another one?), making do with multiple 3F 0-6-0Ts, as being more flexible. Even if that meant more crews, which as Dave Hunt pointed out, that was the whole purpose of the 0-10-0.