Central RR of New Jersey 4-4-2 "Atlantic" Locomotives of the USA


Class Details by Steve Llanso of Sweat House Media

Class 456 / P1 (Locobase 12192)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 20, p. 122. Workd number was 14810 in April 1896.

The CNJ's first Atlantic bucked the trend of camelback Atlantics then coming into use on the anthracite roads against which the railroad competed. Instead of a compound steam system, the CNJ adopted a simple-expansion layout. Tube diameter fell between the more common 1 1/2" and 2 or 2 1/4" as well.

In May 1905, the CNJ rebuilt this engine with 18" cylinders and in January 1912 mounted 79" drivers. 503 was scrapped in November 1926.


Class 582 / P3a (Locobase 12377)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 22, p. 190. Works numbers were 17117-17118, 17184-17186 in October 1899; 17246 in November.

As with almost all Vauclain compounds operated in the USA, these Atlantics were rebuilt with simple-expansion cylinders. The conversion to 19" cylinders came in 1904 (5) and 1905 (1 - 585). Four years later, the CNJ fitted 79" drivers on the class, at which point the railroad designated them class P3.

All but one underwent one more modification when the shops increased cylinder size to 20 1/2"; this occurred over several years beginning in 1914 and ending in 1924. All were reclassified P4s, which suggests that part of the upgrade featured the addtion of a superheater.

By that time, 582, which received its larger cylinders in 1914, had been totalled in a March 1920 wreck. The others were all scrapped in 1928-1929.


Class P-1a (Locobase 10764)

Data from Angus Sinclair, Twentieth Century Locomotives (New York: Railway and Locomotive Engineering, 1904), pp.580-582 . Works numbers were 20965-20966, 20983.

This set of camelback Atlantics was smaller and lighter than the Brooks sextet that had appeared a year earlier (Locobase 5331). In 1909-1910 the three were rebuilt with 79" drivers, but as they lacked the sheer size and grate of the P-6s, they were not superheated.

574 was scrapped first in June 1928, with 572 following a month later, and 573 finishing the class in June 1930.


Class P-6 (Locobase 5331)

Data from table in AERJ July 1903. Like all the other Atlantics on the CNJ, these were camelbacks with very tall drivers. Apparently successful, they endured until 1946-1947.

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 #3951-3953 in August 1901 and numbered 588-590, renumbered 591-593 soon thereafter. Locoba e Cannot tell about the other two.

http://www.insighting.co.uk/homauchchunk/steam_class.htm for photos and further comments.


Class P-6 superheated (Locobase 9447)

Data from CNJ 7 - 1944 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection.

Locobase 5331 shows the sextet of Atlantics as they entered service in 1901. Unlike many of the other American railroads that operated 4-4-2s or Camelbacks, the CNJ held onto their doubly unusual P-6s until the end of steam. But the engines were quite different after a substantial makeover that included increasing piston diameter by 1 1/2" in cylinders supplied by 12" piston valves and reducing the driver diameter by 6 inches. At the same time, adhesion weight went up by more than 15 tons to handle the higher tractive effort. A reconfigured boiler substituted 24 flues (and their superheater elements) for 155 small tubes. Finally, the tender held more water and coal and weighed almost 15 tons more than its older counterpart.

Specifications by Steve Llanso of Sweat House Media
Class456 / P1582 / P3aP-1aP-6P-6 superheated
Locobase ID12192 12377 10764 5331 9447
RailroadCentral RR of New JerseyCentral RR of New JerseyCentral RR of New JerseyCentral RR of New JerseyCentral RR of New Jersey
CountryUSAUSAUSAUSAUSA
Whyte4-4-24-4-24-4-24-4-24-4-2
Number in Class16366
Road Numbers456 / 573 / 570582-587597-599 / 573-574590-595590-595
GaugeStdStdStdStdStd
Number Built1636
BuilderBurnham, Williams & CoBurnham, Williams & CoBurnham, Williams & CoBrooksCNJ
Year18961899190219011917
Valve GearStephensonStephensonStephensonStephensonWalschaert
Locomotive Length and Weight
Driver Wheelbase 7.25' 7.25' 7.25' 7.67' 7.67'
Engine Wheelbase26.42'26.58'26.42'29.83'29.92'
Ratio of driving wheelbase to overall engine wheebase 0.27 0.27 0.27 0.26 0.26
Overall Wheelbase (engine & tender)53.17'53.17'53.67'58.54'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers80000 lbs88000 lbs84100 lbs99400 lbs127800 lbs
Engine Weight141000 lbs167000 lbs151000 lbs191000 lbs215700 lbs
Tender Light Weight100000 lbs99000 lbs124000 lbs153800 lbs
Total Engine and Tender Weight267000 lbs250000 lbs315000 lbs369500 lbs
Tender Water Capacity3500 gals5000 gals5000 gals6000 gals7500 gals
Tender Fuel Capacity (oil/coal)12 tons13 tons
Minimum weight of rail (calculated)67 lb/yard73 lb/yard70 lb/yard83 lb/yard107 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter84.50"84.25"84.50"85"79"
Boiler Pressure200 psi200 psi200 psi210 psi210 psi
High Pressure Cylinders (dia x stroke)18.75" x 26"14" x 26"18" x 26"20.5" x 26"22" x 26"
Low Pressure Cylinders (dia x stroke)24" x 26" (2)
Tractive Effort18389 lbs15344 lbs16948 lbs22946 lbs28433 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.35 5.74 4.96 4.33 4.49
Heating Ability
Firebox Area189.80 sq. ft185.37 sq. ft170.70 sq. ft174 sq. ft173.90 sq. ft
Grate Area76 sq. ft76 sq. ft73 sq. ft82 sq. ft81.63 sq. ft
Evaporative Heating Surface1835 sq. ft2669 sq. ft2174 sq. ft2967 sq. ft2188 sq. ft
Superheating Surface460 sq. ft
Combined Heating Surface1835 sq. ft2669 sq. ft2174 sq. ft2967 sq. ft2648 sq. ft
Evaporative Heating Surface/Cylinder Volume220.84576.16283.90298.72191.27
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation1520015200146001722017142
Same as above plus superheater percentage1520015200146001722020056
Same as above but substitute firebox area for grate area3796037074341403654042727
Power L194377418111361149317397
Power MT520.12371.68583.84509.81600.22


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