North Eastern classes M1 and Q
London & North Eastern classes D17/1 and D17/2
Great Britain 1892 50 produced
Worsdell had 20 class M1 locomotives built from 1892, which, unlike previous express locomotives, did not have a compound engine. From 1896, 30 more of the class Q followed, which had a smaller boiler and slightly larger cylinders. With their driving wheels larger than seven feet, they were used for the fastest trains. In the LNER they became classes D17/1 and D17/2. Most were withdrawn by 1945. Only two D17/2 came to British Railways and were withdrawn in February 1948.
Technical data
General
| Property | M1 | Q |
|---|---|---|
| Built | 1892-1894 | 1896-1897 |
| Manufacturers | Gateshead | |
| Wheel arrangement | 4-4-0 (American) | |
| Gauge | 1,435 mm (Standard gauge) | |
Dimensions and weights
| Property | M1 | Q |
|---|---|---|
| Wheelbase | 7.16 m | 7.24 m |
| Service mass | 51.5 t | |
| Adhesion mass | 34.2 t | |
| Rigid wheelbase | 2.82 m | 2.90 m |
| Axle load | 17.1 t | |
| Water capacity | 18,753 l | |
| Fuel capacity | 5.3 t (coal) | |
Boiler
| Property | M1 | Q |
|---|---|---|
| Grate area | 1.821 m² | 1.835 m² |
| Firebox surface | 11.241 m² | 11.427 m² |
| Tube heating surface | 113.342 m² | 101.172 m² |
| Evaporative heating surface | 124.583 m² | 112.599 m² |
| Total heating surface | 124.6 m² | 112.6 m² |
Power plant
| Property | M1 | Q |
|---|---|---|
| Driver diameter | 2,165 mm | |
| Boiler pressure | 11 bar | 12.4 bar |
| Expansion type | simple expansion | |
| Cylinders | two, 483 x 660 mm | two, 495 x 660 mm |
Power
| Property | M1 | Q |
|---|---|---|
| Power source | steam | |
| Estimated power | 485 kW (659 PS) | 541 kW (736 PS) |
| Starting effort | 66.6 kN | 78.9 kN |
Calculated values
| Property | M1 | Q |
|---|---|---|
| Factor of adhesion | 1 : 5.04 | |
| Optimal speed | 45 km/h | 42 km/h |
| Power-to-weight ratio | 9.4 kW/t | |
| Heating Surface Equivalent | 180.8 m² | 169.7 m² |
| Cylinder volume/HSE | 1 : 1,336.39 | 1 : 1,499.32 |
| Adhesive weight/Total | 1 : 1.50 | |
| Tractive force/Heating surface | 1 : 11.17 | 1 : 14.64 |
| Grate area/Heating surface | 1 : 68.41 | 1 : 61.36 |
| Firebox/Tube surface | 1 : 10.08 | 1 : 8.85 |
