4-4-2 Steam Locomotives in Germany
Prussian State Railways
Class Details by Steve Llanso of Sweat House Media
Class S 7 - Grafenstaden (Locobase 15567)
Data from diagram Lok. 132, Elsassische Maschinenbaugesellschaft rom locomotive book supplied by Dany Machi up at [
] as
Diagrammes des machines SACM construites a GRAFENSTADEN (October 2007). See also "List of Prussian locomotives and railbuses" in Wikipedia at [], last accessed 4 October 2023. Works numbers were 5269-5271 in 1902, 5317-5319 in 1903; 5373-5382, 5502-5511 and 5515-5523 in 1904.
Tube diameter is the interior measurement; external diameter was 50 mm (1.97"). This is clearly a variant of the Prussian State Railways' S7 de Glehn Atlantic (Locobase 9183). The diagram does not indicate how many or for whom this variant was produced. Its tube heating surface area is bigger, but the firebox heating surface area is much smaller.
The Wikipedia table listing Prussian State Railways locomotives subdivides them into a "Standard type" based on the M III-2f (the above-mentioned Locobase 9183) and this Grafenstaden variant "delivered in 3 versions." totalling 79 engines. Jens Merte's SACM production list shows SACM turned out 35, leaving 44 to have been supplied by other manufacturers.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | S 7 - Grafenstaden |
| Locobase ID | 15567 |
| Railroad | Prussian State Railways |
| Country | Germany |
| Whyte | 4-4-2 |
| Number in Class | 79 |
| Road Numbers | |
| Gauge | Std |
| Number Built | 79 |
| Builder | SACM |
| Year | 1904 |
| Valve Gear | Heusinger |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 6.89 / 2.10 |
| Engine Wheelbase (ft / m) | 27.72 / 8.45 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.25 |
| Overall Wheelbase (engine & tender) (ft / m) | 50.03 / 15.25 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 69,446 / 31,500 |
| Engine Weight (lbs / kg) | 138,671 / 62,900 |
| Tender Loaded Weight (lbs / kg) | 105,381 / 47,800 |
| Total Engine and Tender Weight (lbs / kg) | 244,052 / 110,700 |
| Tender Water Capacity (gals / ML) | 5280 / 20 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 6.60 / 6 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 58 / 29 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 78 / 1980 |
| Boiler Pressure (psi / kPa) | 213.20 / 1470 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 13.39" x 25.2" / 340x640 |
| Low Pressure Cylinders (dia x stroke) (in / mm) | 22.05" x 25.2" / 560x640 |
| Tractive Effort (lbs / kg) | 15,338 / 6957.21 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.53 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 257 - 1.969" / 50 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 15.09 / 4.60 |
| Firebox Area (sq ft / m2) | 105.49 / 9.80 |
| Grate Area (sq ft / m2) | 28.74 / 2.67 |
| Evaporative Heating Surface (sq ft / m2) | 1904 / 176.92 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1904 / 176.92 |
| Evaporative Heating Surface/Cylinder Volume | 463.58 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 6127 |
| Same as above plus superheater percentage | 6127 |
| Same as above but substitute firebox area for grate area | 22,490 |
| Power L1 | 6051 |
| Power MT | 384.19 |