For data see "New Mineral Tank Engine, GCR", Locomotive Magazine, Volume XX [20] (15 October 1914), pp.258-259; and "2-6-4 Tank Engines, Great Central Ry.", Locomotive Magazine, Volume XXI [21], No 271 (15 March 1915). See also "The Robinson L1/L3 (GCR Class 1B) 2-6-4T Locomotives" entry from Richard Marsden's LNER Encyclopedia, last accessed at [], 27 November 2017.
JG Robinson inside-cylinder Baltic tank with a Belpaire firebox and 10" (254 mm) piston valves. According to Richard Marsden, this class was based on Class M 0-6-4Ts. He notes that the inside cylinder position caused great stress on the frame and made the cylinders and the ash pans difficult to reach. Marsden adds an style critique: "As with most British 2-6-4T designs, the L1s looked impressive. However, they did not rank amongst Robinson's most aesthetic designs, and they were quickly nicknamed 'Crabs'."
The design was originally intended for coal traffic over the 80 miles (129 km) between Nottinghamshire and Derbyshire collieries and the coal docks as Immingham, but its braking system proved insufficient. As a result the class was moved around the system hauling other types of coal trains.
Although not truly satisfactory, they were adequate and 19 survived to operate on British Rail. Retirements spanned 1949-1957.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 1B/L1/L3 |
| Locobase ID | 2363 |
| Railroad | Great Central |
| Country | Great Britain |
| Whyte | 2-6-4T |
| Number in Class | 20 |
| Road Numbers | |
| Gauge | Std |
| Number Built | 20 |
| Builder | Gorton |
| Year | 1914 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 17 / 5.18 |
| Engine Wheelbase (ft / m) | 37.50 / 11.43 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.45 |
| Overall Wheelbase (engine & tender) (ft / m) | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 44,800 / 20,321 |
| Weight on Drivers (lbs / kg) | 131,600 / 59,693 |
| Engine Weight (lbs / kg) | 215,936 / 97,947 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 3000 / 11.36 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 73 / 36.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 61 / 1549 |
| Boiler Pressure (psi / kPa) | 180 / 1240 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 21" x 26" / 533x660 |
| Tractive Effort (lbs / kg) | 28,759 / 13044.88 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.58 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 157 - 1.875" / 48 |
| Flues (number - dia) (in / mm) | 24 - 5.25" / 133 |
| Flue/Tube length (ft / m) | 12.61 / 5.26 |
| Firebox Area (sq ft / m2) | 157 / 14.59 |
| Grate Area (sq ft / m2) | 26.50 / 2.46 |
| Evaporative Heating Surface (sq ft / m2) | 1547 / 143.40 |
| Superheating Surface (sq ft / m2) | 304 / 19.42 |
| Combined Heating Surface (sq ft / m2) | 1851 / 162.82 |
| Evaporative Heating Surface/Cylinder Volume | 148.42 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 4770 |
| Same as above plus superheater percentage | 5533 |
| Same as above but substitute firebox area for grate area | 32,782 |
| Power L1 | 8898 |
| Power MT | 447.19 |