Data from Mr. Thomas Urquhart, "On the Compounding of Locomotives Burning Petroleum Refuse in Russia", Institute of Mechanical Engineers (London, IME, 1890), pp. 107, 110.
Urquhart's discussion concerned the conversion of already operating locomotives as two-cylinder compounds. At the time of its compounding, the class was rated to pull 720 tons up a 1 in 125 (0.8%) grade. Urquhart had already begun converting many of his locomotives to waste oil burning. Although he extended the stroke on this class compared to the 0-6-0s he'd already converted (Locobase 15791) and reversed the layout to put the LP cylinder on the right-hand side, he still arrived at a very low compounding ratio of less than two.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 68 - compounded |
| Locobase ID | 15791 |
| Railroad | Grazi-Tsaritsin |
| Country | Russia |
| Whyte | 0-8-0 |
| Number in Class | 1 |
| Road Numbers | 68 |
| Gauge | 5' |
| Number Built | |
| Builder | GT |
| Year | 1889 |
| Valve Gear | |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 12.86 / 3.92 |
| Engine Wheelbase (ft / m) | 12.86 / 3.92 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 107,520 / 48,770 |
| Engine Weight (lbs / kg) | 107,520 / 48,770 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 45 / 22.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 48 / 1219 |
| Boiler Pressure (psi / kPa) | 135 / 930 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 20" x 26" / 508x660 (1) |
| Low Pressure Cylinders (dia x stroke) (in / mm) | 27.56" x 26" / 700x660 (1) |
| Tractive Effort (lbs / kg) | 16,286 / 7387.21 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 6.60 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 207 - 2" / 51 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 15.75 / 4.80 |
| Firebox Area (sq ft / m2) | 118 / 10.96 |
| Grate Area (sq ft / m2) | 19 / 1.77 |
| Evaporative Heating Surface (sq ft / m2) | 1815 / 168.62 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1815 / 168.62 |
| Evaporative Heating Surface/Cylinder Volume | 383.97 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2565 |
| Same as above plus superheater percentage | 2565 |
| Same as above but substitute firebox area for grate area | 15,930 |
| Power L1 | 2894 |
| Power MT | 237.36 |