Denver & Rio Grande Western 4-8-2 "Mountain" Type Locomotives

Class 14-34 1/4 E (Locobase 6822)

Data from D&RGW 12 - 1937 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Locobase doesn't know for sure, but believes this, like Locobase 6820) is a proposal submitted to the D&RGW in the 1920s in response to an inquiry about a narrow-gauge Mountain engine; Neither was built, probably because the railway was phasing out narrow-gauge operations.

Class 14-36 1/4 E (Locobase 6821)

Data from D&RGW 12 - 1937 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Locobase doesn't know for sure, but believes this is a proposal submitted to the D&RGW in the 1920s in response to an inquiry about a narrow-gauge Mountain engine; Locobase 6822 shows a smaller version. Neither was built, probably because the railway was phasing out narrow-gauge operations. This design compares well to other narrow-gauge Mountain designs in Locobase (most of which were sized to the Cape Gauge of 42"). It has a lot of boiler for the cylinder volume, a useful degree of superheat, and reasonably tall drivers

Class M-67 (Locobase 1344)

Data from 1937 D & RGW locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection. When built, firebox heating surface totallled 368 sq ft, and included 33 sq ft of arch tubes.. As later modified, the fhs now included the combustion chamber (63 sq ft) and 92 sq ft of thermic syphons in both the firebox proper and in the combustion chamber.

First Mountains built for the Rio Grande, these engines came in three batches, all running on unusually small 63" drivers. 1501-1510 and 1521-1530 were identical; 1511-1520 had a booster engine mounted on the trailing truck and were designated M-78; these ran Grand Junction to Denver.

Class M-75 (Locobase 204)

Firebox had combustion chamber and thermic syphons, boiler had feedwater heater. 10 were built by Baldwin for the D & RGW. They were dual-service locomotives.

Drury (1993) comments: "Their construction by Baldwin is something of a curiosity. They constitute five-sixths of Baldwin's three-cylinder production; and Brooks, which had built D&RGW's two-cylinder Mountains, as the chief advocate of three-cylinder power."

Specifications
Class	14-34 1/4 E	14-36 1/4 E	M-67	M-75
Locobase ID	6822	6821	1344	204
Railroad	Denver & Rio Grande Western (D&RGW)	Denver & Rio Grande Western (D&RGW)	Denver & Rio Grande Western (D&RGW)	Denver & Rio Grande Western (D&RGW)
Whyte	4-8-2	4-8-2	4-8-2	4-8-2
Road Numbers			1501-1530	1600-1609
Gauge	3'	3'	Std	Std
Builder	Baldwin	Baldwin	Brooks	Baldwin
Year			1922	1925
Valve Gear	Walschaert	Walschaert	Walschaert
	Locomotive Length and Weight
Driver Wheelbase	13'	13.75'	17.25'	18.25'
Engine Wheelbase	31.17'	31.92'	39.83'	41.50'
Ratio of driving wheelbase to overall engine wheebase	0.42	0.43	0.43	0.44
Overall Wheelbase (engine & tender)	60.25'	61.17'	82.23'	86.41'
Axle Loading (Maximum Weight per Axle)			64500 lbs
Weight on Drivers	138000 lbs	142000 lbs	257500 lbs	290530 lbs
Engine Weight	181000 lbs	199000 lbs	377000 lbs	419310 lbs
Tender Light Weight	106000 lbs	106000 lbs	277600 lbs
Total Engine and Tender Weight	287000 lbs	305000 lbs	654600 lbs	0
Tender Water Capacity	5000 gals	5000 gals	14000 gals	15000 gals
Tender Fuel Capacity (oil/coal)	8 tons	8 tons	25 tons	25 tons
Minimum weight per yard of rail on which locomotive could run	57.50 lb rail	59.17 lb rail	107.29 lb rail	121.05 lb rail
	Geometry Relating to Tractive Effort
Driver Diameter	44"	48"	67"	67"
Boiler Pressure	190 psi	190 psi	210 psi	210 psi
Cylinders (dia x stroke)	20" x 24"	21" x 24"	28" x 30"	25" x 30" (3)
Tractive Effort	35236 lbs	35611 lbs	62661 lbs	74930 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort)	3.92	3.99	4.11	3.88
	Heating Ability
Firebox Area	144 sq. ft	154 sq. ft	425 sq. ft	512 sq. ft
Grate Area	40.20 sq. ft	42.70 sq. ft	80.20 sq. ft	95 sq. ft
Evaporative Heating Surface	2155	2495	4667	5093
Superheating Surface	505	707	1333	1495
Combined Heating Surface	2660	3202	6000	6588
Evaporative Heating Surface/Cylinder Volume	246.94	259.33	218.29	199.21
	Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation	7638	8113	16842	19950
Same as above plus superheater percentage	9088.07	9904.35	20583.73	24477.21
Same as above but substitute firebox area for grate area	32554.29	35720.59	109078.38	131919.27
Power L1	11847.09	15210.86	20607.87	19360.71
Power MT	757.05	944.62	705.75	587.66