Central RR of New Jersey classes L-6 to L-8
Central RR of New Jersey classes T-38 and T-40
After the classes L-3 to L-5, the ten L-6a built in 1910 were the next Camelback ten-wheelers for commuter service in the roster of the Central Railroad of New Jersey. They still had 69-inch drivers, but were somewhat heavier than their predecessors and had larger cylinders. With their massive Wootten firebox and no full cab behind it, they had a very compact appearance and looked relatively short.
In 1912, ten superheated L-7s followed with cylinders of 23 instead of 22 inches. Between 1928 and 1941, all L-6a were also rebuilt to the L-7s standard by adding a superheated boiler and larger cylinders. The L-7as was created by widening the grate and again a total of ten were built in 1913 and 1914. 1918 saw the introduction of the L-8s, of which again ten were built. These were very similar to the L-7as, but had a higher boiler pressure.
All of these had been built by Baldwin and they got consecutive numbers between 750 and 789. In the new class scheme, the L-7a and L-7as became class T-38, where the “T” stood for the 4-6-0 wheel arrangement (Ten-wheelers) and the 38 stood for a starting tractive effort of 38,000 pounds. In the same way, the L-8s became class T-40. All reached the end of steam, with their retirements only occurring between 1950 and 1954.
Technical data
General
| Property | L-6a | L-7s | L-7as | L-8s |
|---|---|---|---|---|
| Built | 1910 | 1912 | 1913-1914 | 1918 |
| Manufacturers | Baldwin | |||
| Wheel arrangement | 4-6-0 (Ten-wheeler) | |||
| Gauge | 1,435 mm (Standard gauge) | |||
Dimensions and weights
| Property | L-6a | L-7s | L-7as | L-8s |
|---|---|---|---|---|
| Wheelbase | 7.57 m | 7.58 m | 7.67 m | 7.68 m |
| Total wheelbase | 15.89 m | 17.09 m | 17.20 m | |
| Service mass | 88.5 t | 102.1 t | 102.3 t | |
| Adhesion mass | 68 t | 76.7 t | 77.5 t | |
| Total mass | 158.3 t | 168.8 t | 171.2 t | |
| Rigid wheelbase | 4.12 m | |||
| Axle load | 22.7 t | 25.6 t | 25.9 t | |
| Water capacity | 26,498 l | 28,391 l | 28,769 l | |
| Fuel capacity | 14.5 t (coal) | 10.9 t (coal) | 11.8 t (coal) | |
Boiler
| Property | L-6a | L-7s | L-7as | L-8s |
|---|---|---|---|---|
| Grate area | 7.581 m² | 8.491 m² | ||
| Firebox surface | 18.488 m² | 19.417 m² | 19.974 m² | 19.603 m² |
| Tube heating surface | 258.549 m² | 192.031 m² | 194.26 m² | 194.632 m² |
| Evaporative heating surface | 277.037 m² | 211.448 m² | 214.235 m² | |
| Total heating surface | 277.0 m² | 255.5 m² | 258.6 m² | |
| Superheater surface | 44.036 m² | 44.315 m² | ||
Power plant
| Property | L-6a | L-7s | L-7as | L-8s |
|---|---|---|---|---|
| Driver diameter | 1,753 mm | |||
| Boiler pressure | 14.5 bar | 13.8 bar | 15.2 bar | |
| Expansion type | simple expansion | |||
| Cylinders | two, 559 x 711 mm | two, 584 x 711 mm | ||
Power
| Property | L-6a | L-7s | L-7as | L-8s |
|---|---|---|---|---|
| Power source | steam | |||
| Estimated power | 1,119 kW (1,521 PS) | 1,156 kW (1,572 PS) | 1,193 kW (1,622 PS) | 1,342 kW (1,825 PS) |
| Starting effort | 155.9 kN | 170.4 kN | 162.3 kN | 178.6 kN |
Calculated values
| Property | L-6a | L-7s | L-7as | L-8s |
|---|---|---|---|---|
| Factor of adhesion | 1 : 4.28 | 1 : 4.41 | 1 : 4.68 | 1 : 4.26 |
| Optimal speed | 43 km/h | 42 km/h | 45 km/h | 47 km/h |
| Power-to-weight ratio | 12.7 kW/t | 11.3 kW/t | 11.7 kW/t | 13.1 kW/t |
| Heating Surface Equivalent | 369.5 m² | 396.6 m² | 402.7 m² | 400.9 m² |
| Cylinder volume/HSE | 1 : 944.14 | 1 : 961.34 | 1 : 946.71 | 1 : 951.09 |
| Adhesive weight/Total | 1 : 1.30 | 1 : 1.33 | 1 : 1.32 | |
| Tractive force/Heating surface | 1 : 11.76 | 1 : 13.93 | 1 : 13.11 | 1 : 14.42 |
| Grate area/Heating surface | 1 : 36.54 | 1 : 33.70 | 1 : 30.45 | |
| Firebox/Tube surface | 1 : 13.98 | 1 : 9.89 | 1 : 9.73 | 1 : 9.93 |
| Total/Superheater | 1 : 4.80 | 1 : 4.83 | ||