Great Northern (US) class Q-1
The first 30 2-10-2 locomotives ordered by the Great Northern were built by Baldwin in 1923. They were designated class Q-1 and numbered 2100 to 2129. Being one of the heaviest locomotives with this wheel arrangement, they weighed nearly 430,000 pounds. The firebox was of the Belpaire type and had a long combustion chamber. With cylinders of 31 by 32 inches and drivers of 63 inches, starting tractive effort was more than 87,000 pounds. 25 of the 30 class members had a trailing truck booster that added an additional 12,200 pounds.
On Marias Pass in Montana between Whitefish and Cut Bank, they were rated at 3,000 tons. They burned oil, but a small number was later converted to coal. The oil burners originally had Vanderbilt tenders with 15,000 gallons of water and 5,000 gallons of oil. Later most got new ones with 17,000 and 5,800 gallons. Two even got tenders which carried 22,000 gallons of water. All survived into the fifties and the last three were retired in 1957.
Technical data
General
| Property | Standard variant | 2115, 2119 |
|---|---|---|
| Built | 1923 | |
| Manufacturers | Baldwin | |
| Wheel arrangement | 2-10-2 (Santa Fé) | |
| Gauge | 1,435 mm (Standard gauge) | |
Dimensions and weights
| Property | Standard variant | 2115, 2119 |
|---|---|---|
| Length | 29.83 m | 31.42 m |
| Wheelbase | 10.01 m | |
| Total wheelbase | 26.28 m | 28.14 m |
| Service mass | 194.3 t | 191.6 t |
| Adhesion mass | 155.4 t | |
| Total mass | 341.5 t | 360.7 t |
| Rigid wheelbase | 6.71 m | |
| Axle load | 31.7 t | |
| Water capacity | 64,352 l | 83,279 l |
| Fuel capacity | 21,955 l (oil) | |
Boiler
| Property | Standard variant | 2115, 2119 |
|---|---|---|
| Grate area | 8.175 m² | |
| Firebox surface | 37.997 m² | |
| Tube heating surface | 476.5 m² | |
| Evaporative heating surface | 514.498 m² | |
| Superheater surface | 141.027 m² | |
| Total heating surface | 655.5 m² | |
Power plant
| Property | Standard variant | 2115, 2119 |
|---|---|---|
| Driver diameter | 1,600 mm | |
| Boiler pressure | 14.5 bar | |
| Expansion type | simple expansion | |
| Cylinders | two, 787 x 813 mm | |
Power
| Property | Standard variant | 2115, 2119 |
|---|---|---|
| Power source | steam | |
| Estimated power | 2,834 kW (3,853 PS) | |
| Starting effort | 387.6 kN | |
| Starting effort booster | 54.268 kN | |
Calculated values
| Property | Standard variant | 2115, 2119 |
|---|---|---|
| Factor of adhesion | 1 : 3.93 | |
| Optimal speed | 45 km/h | |
| Power-to-weight ratio | 14.6 kW/t | 14.8 kW/t |
| Heating Surface Equivalent | 986.5 m² | |
| Cylinder volume/HSE | 1 : 802.38 | |
| Adhesive weight/Total | 1 : 1.25 | 1 : 1.23 |
| Tractive force/Heating surface | 1 : 12.35 | |
| Grate area/Heating surface | 1 : 80.19 | |
| Firebox/Tube surface | 1 : 12.54 | |
| Total/Superheater | 1 : 3.65 | |