Frisco Lines classes 4100, 4135 and 4150
United States 1923 65 produced
The Frisco Lines received a total of 65 Mikados with additional booster between 1923 and 1926, based on the USRA Heavy Mikado. The first 35 locomotives had Baker valve gear and were fired with coal or oil, depending on the lines. The locomotives from number 4135 had Walschaerts valve gear and thermic syphons. Starting with the 4150, the heating surface has been increased. The first 35 locomotives were later also given Walschaerts valve gear and thermic syphons, as well as slightly larger driving wheels. They were dismissed from service in 1951 and 1952.
Technical data
General
| Property | 4100 | 4100 with thermic syphons | 4135 | 4150 |
|---|---|---|---|---|
| Built | 1923 | 1929 | 1925 | 1926 |
| Manufacturers | Baldwin | Spingfield | Baldwin | |
| Wheel arrangement | 2-8-2 (Mikado) | |||
| Gauge | 1,435 mm (Standard gauge) | |||
Dimensions and weights
| Property | 4100 | 4100 with thermic syphons | 4135 | 4150 |
|---|---|---|---|---|
| Wheelbase | 11.25 m | |||
| Total wheelbase | 22.35 m | 22.61 m | 22.25 m | 22.61 m |
| Service mass | 142 t | 156.3 t | 145.3 t | 158.6 t |
| Adhesion mass | 108.9 t | 107.1 t | 111 t | 120.7 t |
| Total mass | 249.5 t | 263.4 t | 254.4 t | 264.3 t |
| Rigid wheelbase | 5.11 m | |||
| Axle load | 27.2 t | 26.8 t | 27.7 t | 30.2 t |
| Water capacity | 45,425 l | 44,289 l | ||
| Fuel capacity | 17,034 l (oil) | 15.4 t (coal) | 17,034 l (oil) | |
Boiler
| Property | 4100 | 4100 with thermic syphons | 4135 | 4150 |
|---|---|---|---|---|
| Grate area | 6.531 m² | |||
| Firebox surface | 26.57 m² | 35.303 m² | 35.396 m² | |
| Tube heating surface | 340.583 m² | 341.976 m² | 340.583 m² | 342.998 m² |
| Evaporative heating surface | 367.153 m² | 377.28 m² | 375.979 m² | 378.394 m² |
| Superheater surface | 97.362 m² | 92.253 m² | 98.756 m² | 104.609 m² |
| Total heating surface | 464.5 m² | 469.5 m² | 474.7 m² | 483.0 m² |
Power plant
| Property | 4100 | 4100 with thermic syphons | 4135 | 4150 |
|---|---|---|---|---|
| Driver diameter | 1,600 mm | 1,626 mm | 1,600 mm | |
| Boiler pressure | 13.1 bar | 13.8 bar | 13.1 bar | 13.8 bar |
| Expansion type | simple expansion | |||
| Cylinders | two, 686 x 813 mm | |||
Power
| Property | 4100 | 4100 with thermic syphons | 4135 | 4150 |
|---|---|---|---|---|
| Power source | steam | |||
| Estimated power | 2,386 kW (3,244 PS) | 2,424 kW (3,296 PS) | 2,312 kW (3,143 PS) | 2,610 kW (3,549 PS) |
| Starting effort | 266.0 kN | 275.6 kN | 266.0 kN | 280.0 kN |
| Starting effort booster | 49.82 kN | 55.158 kN | 49.82 kN | |
Calculated values
| Property | 4100 | 4100 with thermic syphons | 4135 | 4150 |
|---|---|---|---|---|
| Factor of adhesion | 1 : 4.01 | 1 : 3.81 | 1 : 4.09 | 1 : 4.23 |
| Optimal speed | 55 km/h | 53 km/h | 56 km/h | |
| Power-to-weight ratio | 16.8 kW/t | 15.5 kW/t | 15.9 kW/t | 16.5 kW/t |
| Heating Surface Equivalent | 694.7 m² | 738.3 m² | 750.5 m² | 764.6 m² |
| Cylinder volume/HSE | 1 : 864.34 | 1 : 813.33 | 1 : 800.14 | 1 : 785.36 |
| Adhesive weight/Total | 1 : 1.30 | 1 : 1.46 | 1 : 1.31 | |
| Tractive force/Heating surface | 1 : 11.96 | 1 : 12.26 | 1 : 11.70 | 1 : 12.11 |
| Grate area/Heating surface | 1 : 71.12 | 1 : 71.89 | 1 : 72.69 | 1 : 73.96 |
| Firebox/Tube surface | 1 : 12.82 | 1 : 9.69 | 1 : 9.62 | 1 : 9.69 |
| Total/Superheater | 1 : 3.77 | 1 : 4.09 | 1 : 3.81 | 1 : 3.62 |
