Official B.B. Britannia boiler drawing

[92220]

Hi all.

I want to compare the B.R. Britannia boiler drawing with the B.R. 9F boiler drawing. I know the 9F boiler was 24" shorter than the Brit boiler, but I want to compare all the outside dimensions. Can anyone tell me the British Railways drawing number for the Brit Boiler Arrangement drawing? I can't find it in the NRM drawing registers. I'm sure it's there but I haven't been able to find it. I also want to see if there is any indication of how the footplates are fixed along the sides as the 9F boiler arrangement doesn't show any mounting points. Any help much appreciated.

[standardsteam]

Sorry I don't have the number, but Philip Atkins wrote books on both the Britannia and the 9F (The British Railways Standard 9F 2-10-0s). His book on the Britannia has the firebox and I think boiler drawing much reduced, I'll have a look in his 9F book to see if he did the same as I can't remember of the top of my head.

[Jim]

I have a copy of GA drawing of the Britannia plus tender from the Derby Drawing Office. I'll see what I can get from that.

Jim

[92220]

Thanks all. I've just found what I am looking for. Would you believe...it's the very first drawing in the Derby drawing register - SL/DE/19500. Blind as a bat; that's me!!!

[Jim]

Welcome to the club

[standardsteam]

Data from Philip Atkins book on the 9Fs - BR 7 compared with BR 9 - errors in transcription are mine..

Boiler Type BR1 BR9
Boiler Pressure 250lb 250lb
Min. boiler diameter 5'9" 5'9"
Max. boiler diameter 6'5.5" 6'1"
Tube length 17'0" 15'3"
No./Diameter of flues 40/5.5" 35/5.25"
No./Diameter of tubes 136/2.125" 138/2"
Tube heating surface ft(2). 2264 1836
Firebox heating surface ft(2). 210 179
Evaporative heating surface ft(2). 2474 2015
Superheater heating surface ft(2). 718 535
Grate area ft(2). 42 40.2
Free gas area ft(2). 6.79 5.45
Firebox volume ft(3). 273 213
Gas area/grate. 0.162 0.136
Firebox vol/grate. 6.50 5.30
Empty Weight tons. 24.75 21.4