Central RR of New Jersey 4-8-0 "Mastodon" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class K-1 (Locobase 1222)

Data from the 1899 Brooks catalogue. See also "Central of New Jersey Twelve-Wheeler", Locomotive Engineering, Vol 12, No. 3 (June 1899), p. 285

Builder info from B.Rumary, 25 Kingscombe, Gurney Slade, Radstock, BA3 4TH, ENGLAND and Jeremy Lambert as supplied by Allen Stanley in March 2004. Works #3167-3181, produced in March 1899, 3331-3320 in October 1899, 3540-3554 in May 1900, 3820 in April 1901, 3957-3966 in September 1901.

Original 426-429 were later renumbered 441-444.

Original 441-444 were renumbered 451-454

Original 451-454 were renumbered 466-469

Original 466 was renumbered 480.

Original 467-469 were renumbered 477-479.

Locobase doesn't understand any of this ...

This camelback featured a wide Wooten firebox (123" long by 97" wide) for burning fine anthracite coal that was stoked by two firemen. Rumary-Lambert indicate that the first 15 later received 20" x 32" cylinders,

The design was delivered with slide valves driven by inside Stephenson gear; drive was on the second coupled axle.

As rare in American service as was the Twelve-wheeler, the 4-8-0s in this large stud obviously suited the CNJ's hilly profile and anthracite fuel quite well. The first reports said that the K-1s were handling 3,000 tons over "a somewhat undulating division". When new steel 50-ton cars (presumably presenting less resistance) were delivered, the railroad expected to haul 4,000 tons.

Later photographs indicate that this class was rebuilt with 11" piston valves and Baker valve gear and almost all of the class was superheated. (See Locobase 6724).

About half were scrapped before World War II, while the other half served into the late 1940s.

Class K-1as / TW40 - superheated (Locobase 6724)

Data from CNJ 7 - 1944 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection. http://www.insighting.co.uk/homauchchunk/steam_by_year.htm

The CNJ was sufficiently pleased with its large stud of Twelve-wheelers (See Locobase 1222) to take the considerable trouble of superheating the boiler on the great majority of those still in service. Compared to the original Brooks specs as spelled out in the 1899 catalogue, the modified boiler supplied a useful increase in power. Although some sources say the retrofit included Walschaert valve gear, the 1944 book shows Baker gear instead. All were refitted with 11" (279 mm) piston valves.

Most of the engines were rebuilt between 1921 and 1924. Many were sold in the 1930s, but a significant number served the CNJ throughout World War Two. Those still in service were redesignated TW-40. Withdrawals followed quickly in 1945-1947 with one engine, 465, sold for scrap in November 1948.

Specifications by Steve Llanso of Sweat House Media
ClassK-1K-1as / TW40 - superheated
Locobase ID1222 6724
RailroadCentral RR of New JerseyCentral RR of New Jersey
Number in Class5045
Road Numbers426-475 / 430-480431 etc.
Number Built50
Valve GearStephensonBaker
Locomotive Length and Weight
Driver Wheelbase (ft)1515
Engine Wheelbase (ft)25.7525.75
Ratio of driving wheelbase to overall engine wheebase 0.58 0.58
Overall Wheelbase (engine & tender) (ft)5353.90
Axle Loading (Maximum Weight per Axle) (lbs)
Weight on Drivers (lbs)159,000167,000
Engine Weight (lbs)201,000217,000
Tender Loaded Weight (lbs)138,600141,800
Total Engine and Tender Weight (lbs)339,600358,800
Tender Water Capacity (gals)70007000
Tender Fuel Capacity (oil/coal) (gals/tons)12.5016
Minimum weight of rail (calculated) (lb/yd)6670
Geometry Relating to Tractive Effort
Driver Diameter (in)5555
Boiler Pressure (psi)200200
High Pressure Cylinders (dia x stroke) (in)21" x 32"20" x 32"
Tractive Effort (lbs)43,61939,564
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.65 4.22
Heating Ability
Firebox Area (sq ft)218201.30
Grate Area (sq ft)82.4081.63
Evaporative Heating Surface (sq ft)29502414
Superheating Surface (sq ft)474
Combined Heating Surface (sq ft)29502888
Evaporative Heating Surface/Cylinder Volume229.96207.47
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation16,48016,326
Same as above plus superheater percentage16,48018,938
Same as above but substitute firebox area for grate area43,60046,702
Power L1577412,111
Power MT320.24639.52

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