The first to arrive were fifteen of the 2-10-4s (road numbers 850 through 864) from Lima in 1930. Another three (road numbers 880 through 882) came from Lima in the same year. These eighteen locomotives were designated as Class T-1 and had 63" diameter drivers, 29" x 32" cylinders, a 255 psi boiler pressure, a tractive effort of 84,600 pounds and each weighed 462,900 pounds.
Another nine, "Texas" type locomotives were received from Baldwin in 1930. These locomotives were built to the same basic specifications as the T-1s, but weighed 463,980 pounds. They were designated as Class T-2 and were assigned road numbers 865 through 873.
All thirty-six of the coal burning CGW "Texas" type locomotives were retired between 1948 and 1950, and today there are no surviving examples
|Class||Qty.||Road Number||Year Built||Builder||Notes|
Firebox heating surface included 98 sq ft in two thermic syphons (9.1 sq m), 91 sq ft (8.45 sq m) from the combustion chamber, and 21 sq ft (1.95 sq m) of arch tubes. All had 14" (356 mm) piston valves.
Drury (1993) claims that these were duplicates of the Texas & Pacific 600-series locomotives -- and in terms of basic power, they were. He notes the few differences: "coal instead of oil fuel, a second sand dome behind the steam dome, and Coffin or Worthington [Type S] feedwater heaters."
The 1943 diagram book suggests a very different origin. Alone among the American and Canadian 2-10-4s, these locomotives retained the 5 1/2" flues for the superheater. The areas are considerably smaller than those of the T&P engines.
An interesting vignette on the impact of these "Big Hogs" comes from aRail Data Exchange of stories about the CGW put up on [external link] by Jim L. Rueber (visited 11 August 2004):
"To help pay for these huge engines" Rueber says, "a lot of employees lost their jobs. The shop force at Oelwein, Iowa was reduced. The Terminals at East Stockton, Illinois and Conception, Missouri were closed. These bigger engines resulted in fewer trains so the trainmen and enginemen took a hit. Even the operators at the various coal chutes were reduced to just one man."
Rueber adds that when a superintendent asked engineer Frank Anderson whether he liked the new engines, Anderson replied, "I don't". When Foster, the super, followed with "Why not?", Anderson said, "They pull too many cars."
T-1 850-864 Lima 1930, 880-882 Lima 1931
T-2 865-873 Baldwin 1930 - Worthington feedwater heaters
T-3 874-879 Baldwin 1931 (Baldwin works numbers came in a batch 61573-61587 in December 1930) - Coffin feedwater heaters.
883-885 Lima 1931
Baldwin's 1941 article noted that when they were delivered "[t]he wheels were statically balanced, and approximately 50% of the reciprocating weight was balanced in accordance with the accepted practice of the time." But all of the reciprocating balance was placed on the wheels in axles 1, 2, 4, and 5. Because the main drivers (the third set) took all of the load and whirling weight of the main rod, but were not balanced, increased speeds induced vibrations that "resulted in rough riding and proved hard on the track."
So in 1937 the CGW began replacing the original spoke wheels with Baldwin disc centers that had "triangular sections in the rim and adjacent to the hub.". In addition to strengthening the drivers, the change reduced the size of axle and crank pin hubs. This reduced the amount of weight to be counterbalanced even as it provided more space to add what was needed. The new discs and counterbalance also reduced dynamic augment to a striking degree, especially at higher speeds.
In 1939, Baldwin supplied lighter-weight main rods and tandem connecting rods. When installed, the weights on the main pin dropped from 1,385 lb to 1,076 lb, a reduction of 22%.
All left service in 1948-1950.
|Principal Dimensions by Steve Llanso of Sweat House Media|
|Railroad||Chicago Great Western (CGW)|
|Number in Class||36|
|Locomotive Length and Weight|
|Driver Wheelbase (ft / m)||21.50 / 6.55|
|Engine Wheelbase (ft / m)||46.67 / 14.23|
|Ratio of driving wheelbase to overall engine wheebase||0.46|
|Overall Wheelbase (engine & tender) (ft / m)||87.50 / 26.67|
|Axle Loading (Maximum Weight per Axle) (lbs / kg)|
|Weight on Drivers (lbs / kg)||304,190 / 137,978|
|Engine Weight (lbs / kg)||455,310 / 206,525|
|Tender Loaded Weight (lbs / kg)||311,700 / 141,385|
|Total Engine and Tender Weight (lbs / kg)||767,010 / 347,910|
|Tender Water Capacity (gals / ML)||14,000 / 53.03|
|Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)||25 / 22.70|
|Minimum weight of rail (calculated) (lb/yd / kg/m)||101 / 50.50|
|Geometry Relating to Tractive Effort|
|Driver Diameter (in / mm)||63 / 1600|
|Boiler Pressure (psi / kPa)||255 / 17.60|
|High Pressure Cylinders (dia x stroke) (in / mm)||29" x 32" / 737x813|
|Tractive Effort (lbs / kg)||92,590 / 41998.17|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||3.29|
|Firebox Area (sq ft / m2)||494 / 45.89|
|Grate Area (sq ft / m2)||100 / 9.29|
|Evaporative Heating Surface (sq ft / m2)||4769 / 443.05|
|Superheating Surface (sq ft / m2)||1325 / 123.10|
|Combined Heating Surface (sq ft / m2)||6094 / 566.15|
|Evaporative Heating Surface/Cylinder Volume||194.94|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||25,500|
|Same as above plus superheater percentage||31,110|
|Same as above but substitute firebox area for grate area||153,683|