Austrian Southern Railway and Imperial-Royal State Railways class 629
Czechoslovak State Railways class 354.1, Polish State Railways OKm11, German Reichsbahn class 772-3, and Austrian Federal Railways class 77
Ernst Prossy developed the class 629 for the Südbahn based on the class 229 2-6-2T tank locomotive of the Südbahn and kkStB. It had a leading bogie in order to be able to increase power while maintaining the axle and meter loads. With an unchanged driving wheel diameter of 1,614 mm (63.5 inches), they were suitable for passenger and light express trains. Approval was initially granted for 85 km/h and later increased to 90 km/h, and even 110 km/h was attained on test runs.
After the Südbahn had received 15, Gölsdorf also adopted the design with small changes for the kkStB and had 25 more built. Larger numbers were only created after the First World War, when the BBÖ, the ČSD and the PKP ordered greater numbers. The ČSD in particular ultimately made it to a total of 234 with its class 354.1 locomotives built by Škoda. These were characterized by two steam domes with a connecting pipe.
Technical data
General
| Property | 1913 variant | 1927 variant |
|---|---|---|
| Built | 1913-1922 | 1927-1928 |
| Manufacturers | StEG, Wiener Neustadt, Krauss Linz, Škoda | |
| Wheel arrangement | 4-6-2T (Pacific) | |
| Gauge | 1,435 mm (Standard gauge) | |
Dimensions and weights
| Property | 1913 variant | 1927 variant |
|---|---|---|
| Length | 13.35 m | |
| Wheelbase | 9.59 m | |
| Service mass | 80.2 t | 83.8 t |
| Adhesion mass | 43.2 t | 45 t |
| Rigid wheelbase | 3.60 m | |
| Axle load | 14.4 t | 15 t |
| Water capacity | 12,000 l | |
| Fuel capacity | 3 t (coal) | |
Boiler
| Property | 1913 variant | 1927 variant |
|---|---|---|
| Grate area | 2.7 m² | |
| Firebox surface | 12.2 m² | |
| Tube heating surface | 129.65 m² | |
| Evaporative heating surface | 141.85 m² | |
| Superheater surface | 33.75 m² | |
| Total heating surface | 175.6 m² | |
Power plant
| Property | 1913 variant | 1927 variant |
|---|---|---|
| Driver diameter | 1,614 mm | |
| Boiler pressure | 13 bar | |
| Expansion type | simple expansion | |
| Cylinders | two, 475 x 720 mm | |
Power
| Property | 1913 variant | 1927 variant |
|---|---|---|
| Power source | steam | |
| Indicated power | 830 kW (1,128 PS) | |
| Top speed | 90 km/h | |
| Starting effort | 111.2 kN | |
Calculated values
| Property | 1913 variant | 1927 variant |
|---|---|---|
| Factor of adhesion | 1 : 3.81 | 1 : 3.97 |
| Optimal speed | 45 km/h | |
| Power-to-weight ratio | 10.3 kW/t | 9.9 kW/t |
| Heating Surface Equivalent | 270.4 m² | |
| Cylinder volume/HSE | 1 : 943.87 | |
| Adhesive weight/Total | 1 : 1.86 | |
| Tractive force/Heating surface | 1 : 13.23 | |
| Grate area/Heating surface | 1 : 65.04 | |
| Firebox/Tube surface | 1 : 10.63 | |
| Total/Superheater | 1 : 4.20 | |
