Philadelphia & Reading 4-6-2 "Pacific" Type Locomotives

Introduction

The first 30 of Reading class G1sa Pacifics were built at the Reading shops from 1916-1922. The last five of this class were built by Baldwin in 1924. With 40,900 lbs starting te and 80 inch drivers, these were certainly not light Pacifcs. They had a Wootten type firebox, designed for burning an anthracite waste product, "culm", and anthracite coal in general. Similar Pacifics were to be found on the Central New Jersey, the Lehigh Valley the Delaware, Lackawanna & Western

In 1948, Reading Shops built Class G3 (no more "s", just as on the Pennsy)) 210-219. Basically, these were developments of a later version of 124, class G2sa. They had higher boiler pressure, and such details as a Worthington SA feedwater heater and cast steel engine beds. Under the combined onslaught of diesels and the debilitating effect of declining passenger traffic, they were all gone within nine years. One of the places where they worked was on the Pennsylvania- Reading Seashore Line, during the summer rush. Actually, on PRSL runs which served PRR 30th Street, they may well have been the last steam locomotives to haul passenger trains in Philadelphia.

Class Details by Steve Llanso

Class G1-sa (Locobase 445)

Data from Railway Age Gazette (21 July 1916), pp 107-109. See also DeGolyer, Vol 74, pp. 89 + and RDG 11 - 1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Wooten type boiler

First Pacifics (five in the order) bought by the Philadelphia and Reading. RA's report commented that the valve gear and reciprocating parts had been made as light as possible to "reduce the ill effects from the counterbalancing." The piston load per pound of reciprocating parts was 79 lb and 65% of the reciprocating parts was balanced. The result was a dynamic augment of 41.5% of the static weight at 80 mph. Inside-admission piston valves measured 12" (306 mm) in diameter.

Used on the Boardwalk Flyer between Philadelphia and Atlantic City. Reading built 25, Baldwin the last five in a batch (works #57756-57760) in April 1924. Baldwin built another five in 1925 with 74" drivers; see Locobase 9411.

Class G1-sb (Locobase 9411)

Data from Reading 11 - 1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection. See also DeGolyer, Vol 74, pp. 102+. Works numbers were 58264-58266, 58291-58292 in March 1925.

Locobase 445 shows the lion's share of this design, the version that rolled on 80" (2,032 mm) drivers. To finish the class in 1925, the Reading bought five from Baldwin with smaller drivers. Otherwise they were repeats of the G1-sa down to the 12" (305 mm) inside-admission piston valves."

Class G2-sa (Locobase 158)

Data from tables in 1930 Locomotive Cyclopedia, supplemented by Reading 11 - 1926 Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Built 10 years after the first Pacifics on the Reading (Locobase 445), these Baldwins (works 59226, 59254-59258) differed only in small details. They were fitted with the large Wootten firebox fitted to most Reading engines. Westcott (1960) says these engines "were carefully designed so they could run as fast as the Reading's Atlantics". Used on the Boardwalk Flyer between Philadelphia and Atlantic City.


Specifications by Steve Llanso
ClassG1-saG1-sbG2-sa
Locobase ID445 9411 158
RailroadPhiladelphia & ReadingPhiladelphia & ReadingPhiladelphia & Reading
Whyte4-6-24-6-24-6-2
Road Numbers105-134200-204175-179
GaugeStdStdStd
BuilderseveralseveralBaldwin
Year191619251926
Valve GearWalschaertWalschaertWalschaert
Locomotive Length and Weight
Driver Wheelbase13.83'13.83'13.83'
Engine Wheelbase35.58'35.58'35.92'
Ratio of driving wheelbase to overall engine wheebase 0.39 0.39 0.39
Overall Wheelbase (engine & tender)67.98'67.98'72.20'
Axle Loading (Maximum Weight per Axle)61000 lbs59120 lbs64860 lbs
Weight on Drivers176900 lbs177210 lbs192540 lbs
Engine Weight273600 lbs288120 lbs306360 lbs
Tender Light Weight160000 lbs183000 lbs154000 lbs
Total Engine and Tender Weight433600 lbs471120 lbs460360 lbs
Tender Water Capacity8000 gals9000 gals9000 gals
Tender Fuel Capacity (oil/coal)12.9 tons16 tons15 tons
Minimum weight of rail (calculated) on which locomotive could run98 lb/yard98 lb/yard107 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter80"74"80"
Boiler Pressure220 psi220 psi230 psi
Cylinders (dia x stroke)25" x 28"25" x 28"25" x 28"
Tractive Effort40906 lbs44223 lbs42766 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.32 4.01 4.50
Heating Ability
Firebox Area282 sq. ft282 sq. ft314 sq. ft
Grate Area94.50 sq. ft94.50 sq. ft95 sq. ft
Evaporative Heating Surface2926 sq. ft2926 sq. ft3045 sq. ft
Superheating Surface652 sq. ft652 sq. ft745 sq. ft
Combined Heating Surface3578 sq. ft3578 sq. ft3790 sq. ft
Evaporative Heating Surface/Cylinder Volume183.93183.93191.41
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation207902079021850
Same as above plus superheater percentage245322453226220
Same as above but substitute firebox area for grate area732077320786664
Power L1188161740421822
Power MT703.48649.55749.60

Photos

Reference

Credits

Introduction and roster provided by Richard Duley. Class details and specifications provided by Steve Llanso of Sweat House Media.