Lehigh Valley 2-8-2 "Mikado" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class N-1 (Locobase 12681)

Data from "Locomotive Building," The Railway Gazette, Vol XXXIX, No 24 (15 December 1905), p. 191 and Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 28, p. 190. Works numbers for Baldwin engines were 27665-27666, 27693, 27698, 27699, 27713-27714, 27726, 27756 in March 1905; 27783 in April. Alco's engines bore the higher road numbers.

Camelback with low drivers for slogging through the eastern Pennsylvania coal country on the Lehigh Valley. These were the only camelbacks built in the Mikado wheel arrangement and came to the LV in two sub-classes. Such double-end "Mother Hubbards" were rare and photographs show that placing the cab ahead of the massive Wootten firebox created a "center-cab" look when seen above 6 axles.

The first group seems to have stuffed the relatively slim border with too many tubes. When Locobase compares the design with other saturated-boiler Mikes of the same vintage, those that had 2 1/4" tubes also show significantly larger diameters of boiler.

Another sign that the installation may have proved too crowded appears in the later batch, which was split between Baldwin and Alco. See Locobase 1359.

Even so, a paid-for engine counts for a lot and all of the N-1s enjoyed 20+-year careers before being scrapped in 1924-1932.


Class N-1 (Locobase 1359)

Data from "Locomotive Building," The Railway Gazette, Vol XXXIX, No 24 (15 December 1905), p. 191 and Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 28, p. 190. Works numbers for Baldwin engines were 27665-27666, 27693, 27698, 27699, 27713-27714, 27726, 27756 in March 1905; 27783 in April. Alco's engines bore the higher road numbers.

The repeat order for camelback Mikados came two years after Baldwin's 27 were delivered (as described in Locobase 12681. Apparently finding that 343 2 1/4" tubes in a 72" boiler crowded the vessel intolerably, the railroad's next order pared the count by 25. (Interestingly, this was still a pretty big count for a saturated-boiler Mikado.) The desing also increased adhesive weight by 4 1/2 tons.

Locobase occasionally reproduces the equipment list that often accompanied RG's longer entries in the "Locomotive Building" department of the journal.

Baldwin's production of this 10-engine order made use of:

Westinghouse air brakes

Snow bell ringers

Keasbey & Mattison magnesia boiler lagging

Diamond special brake-beams

Tower all-steel couplers

Glazier headlights

Hancock Injectors

Magnus Metal Co.'s journal bearings

U. S. metallic piston and valve packings

Consolidated safety valves

Leach sanding devices

Detroit sight-feed lubricators

Railway Steel Spring Co.'s springs

Ashcroft steam gages

Latrobe driving, truck and tender wheel tires and cast steel wheel centers for driving wheels.

Almost all the N-1s had 20+-year careers on the LV. A few were scrapped in 1924 while a few lasted into 1932.


Class N-2 (Locobase 1360)

Data from LV 3 - 1934 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 43, p. 43-58. Works numbers were

1912

December 38942, 38989-38994

1913

February 39233-39238, 39303-39306; June 39972-39976, 39989-39992, 40041-40044, 40092-40094; July 40105-40106, 40151-40153, 40201-40254.

These Mikes followed the N-1 camelbacks. Although conventional in layout, they also had the Wooten firebox.and a big boiler to go with it. Piston valves measured 14" (356 mm) in diameter. The specifications included the desire to have the crown and side sheets to be made in one piece "if material of sufficient dimensions can be obtained."

Nineteen were scrapped before the US entered World War II, most of these in 1938 (7) and 1939 (6). When war preparations gained traction in 1940, the railroad held on to most of the rest, scrapping only 6 in 1940 (3) and 1941 (3). The next retirement call summoned 332 in July 1947 and 308 followed in October 1948, but most of the class went to the scrapyard in 1949 (9), 1950 (8), and 1951 (4).


Class N-21/2 (Locobase 14596)

Data from DeGolyer, Vol 48, pp. 103+ and Vol 59, pp. 213+. Works numbers were

1913

40441-40442 in August; 40520-40521, 40525-40527, 40581-40588, 40654-40655, 40692-40694 in September; 40701-40702, 40705-40707 in October.

1916

42830-42831 in January; 42849-42851, 42909-42911, 42940-42941. 42953-42959 in February; 43001-43003 in March.

These Mikes repeated the Wootten-firebox N-2s that had brought such a large boiler to the LV through the adoption of 21-ft long tubes. The one difference (and it was an important one) was the use of 62" (later 63") drivers in place of the N-2's 56" (1422 mm) wheels.


Class N-3 (Locobase 5448)

Data from table in May 1916 issue of Railway Mechanical Engineer (RME). See also DeGolyer, Vol 59, pp. 224 and Vol 68, pp. 1+. Works numbers were spread out over six years:

1916

June 43503-43506, 43532-43533, 43544-43547; July 43714-43717, 43787-43792

1921

January 54258, 54344-54345, 54346-54347

1922

August 55552; October 55691-55694

These were described as improved N-2s. Firebox heating surface included 59 sq ft (5.5 sq m) of arch tubes and a 88-sq ft (8.2 sq m) combustion chamber. Note too that the 3 1/2 feet (1,067 mm) of combustion chamber reduced the tube length. Note the high percentage of combined heating surface that was directly heated, a result of the use of the anthracite-burning Wootten firebox. 14" (356 mm) piston valves supplied the cylinders.

Also notice that the boiler's tube & flue count (254 & 45) matched that of the R-1 2-10-2, although those of the the latter design were four feet longer. The 1916 engines used Walschaert radial valve gear. The last ten operated the "Latest Improved" Baker gear.


Class N-4/N-4B (Locobase 7306)

Data from LV 3 -1934 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer Library, Vol 68, pp. 27+. Works numbers were 55894-55896 in December 1922 and 56023-56024, 56088-56097 in January 1923.

Locobase concludes that the Lehigh Valley was happy with the boiler they'd been using on their Mikados as this class had an identical layout of tubes and flues to those of the pre-World War I engines. The firebox, on the other hand, was of conventional width and burned a mixture of bituminous and fine anthracite coal. The shorter firebox allowed a longer combustion chamber contributed 112 sq ft (10.4 sq m) to direct heating surface area along with 40 sq ft (3.7 sq m) of arch tubes. The N-4B used an 8,000-gallon tender.

With the likely exception of one or two locomotives with the early retirement date of 1940, this class served the LV until the end of steam.


Class N-5 (Locobase 7307)

Data from LV 3 -1934 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

As the Lehigh Valley took delivery of the 20 Baldwins that followed the earlier pattern of boiler and cylinder dimensions, Alco started supplying a juiced-up variant in greater numbers. Cylinder stroke increased by two inches and 20 tubes were traded for 5 flues. This resulted in a slightly smaller amount of heating surface - direct and tube-flue - but more starting tractive effort.

The design obviously suited the LV as all of these engines stayed in service until the end of steam.

Specifications by Steve Llanso of Sweat House Media
ClassN-1N-1N-2N-21/2N-3
Locobase ID12,681 1359 1360 14,596 5448
RailroadLehigh Valley (LV)Lehigh Valley (LV)Lehigh Valley (LV)Lehigh Valley (LV)Lehigh Valley (LV)
CountryUSAUSAUSAUSAUSA
Whyte2-8-22-8-22-8-22-8-22-8-2
Number in Class2720424530
Road Numbers1501-1527 / 220-246247-266300-341350-394395-424
GaugeStdStdStdStdStd
Number Built2720424530
BuilderBurnham, Williams & CoseveralBaldwinBaldwinBaldwin
Year19031905191219131916
Valve GearStephensonStephensonWalschaertWalschaertBaker or Walschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)15 / 4.5715 / 4.5716.50 / 5.0316.50 / 5.0315.75 / 4.80
Engine Wheelbase (ft / m)31.25 / 9.5231.25 / 9.5235.17 / 10.7235.17 / 10.7234.33 / 10.46
Ratio of driving wheelbase to overall engine wheebase 0.48 0.48 0.47 0.47 0.46
Overall Wheelbase (engine & tender) (ft / m)37.96 / 11.5767.96 / 20.7169.58 / 21.21
Axle Loading (Maximum Weight per Axle) (lbs / kg)60,000 / 27,21660,000 / 27,216
Weight on Drivers (lbs / kg)173,000 / 78,472182,000 / 82,554235,000 / 106,594235,000 / 106,594232,000 / 105,234
Engine Weight (lbs / kg)232,000 / 105,234234,810 / 106,508322,000 / 146,057322,000 / 146,057325,200 / 147,508
Tender Loaded Weight (lbs / kg)150,000 / 68,039150,000155,200 / 70,398154,800 / 70,216154,800 / 70,216
Total Engine and Tender Weight (lbs / kg)382,000 / 173,273384,810477,200 / 216,455476,800 / 216,273480,000 / 217,724
Tender Water Capacity (gals / ML)8000 / 30.308000 / 30.308000 / 30.308000 / 30.308000 / 30.30
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 8.50 / 7.70 8.50 / 7.7012 / 10.9012.50 / 11.4012.50 / 11.40
Minimum weight of rail (calculated) (lb/yd / kg/m)72 / 3676 / 3898 / 4998 / 4997 / 48.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)55.50 / 141056 / 142256 / 142262 / 157563 / 1600
Boiler Pressure (psi / kPa)200 / 13.80200 / 13.80180 / 12.40190 / 13.10190 / 13.10
High Pressure Cylinders (dia x stroke) (in / mm)22.5" x 28" / 572x71122.5" x 28" / 572x71127" x 30" / 686x76227" x 30" / 686x76227" x 30" / 686x762
Tractive Effort (lbs / kg)43,419 / 19694.5543,031 / 19518.5659,752 / 27103.0856,968 / 25840.2856,064 / 25430.23
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.98 4.23 3.93 4.13 4.14
Heating Ability
Firebox Area (sq ft / m2)215 / 19.98216 / 18.17314 / 29.18274 / 29.93416 / 38.65
Grate Area (sq ft / m2)87.70 / 8.1587.70 / 8.15100 / 9.29100 / 9.29100 / 9.29
Evaporative Heating Surface (sq ft / m2)3830 / 355.953570 / 330.484877 / 453.254821 / 447.884150 / 385.54
Superheating Surface (sq ft / m2)1100 / 102.231101 / 102.29980 / 91.04
Combined Heating Surface (sq ft / m2)3830 / 355.953570 / 330.485977 / 555.485922 / 550.175130 / 476.58
Evaporative Heating Surface/Cylinder Volume297.23277.06245.32242.50208.75
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation17,54017,54018,00019,00019,000
Same as above plus superheater percentage17,54017,54021,24022,61022,610
Same as above but substitute firebox area for grate area43,00043,20066,69461,95194,058
Power L17042673613,81415,90015,103
Power MT358.96326.38518.38596.65574.08

Specifications by Steve Llanso of Sweat House Media
ClassN-4/N-4BN-5
Locobase ID7306 7307
RailroadLehigh Valley (LV)Lehigh Valley (LV)
CountryUSAUSA
Whyte2-8-22-8-2
Number in Class1555
Road Numbers425-434, 460-464440-459, 465-499
GaugeStdStd
Number Built1555
BuilderBaldwinAlco-Schenectady
Year19231923
Valve GearBakerBaker
Locomotive Length and Weight
Driver Wheelbase (ft / m)16.50 / 5.0316.50 / 5.03
Engine Wheelbase (ft / m)36.50 / 11.1337.08 / 11.30
Ratio of driving wheelbase to overall engine wheebase 0.45 0.44
Overall Wheelbase (engine & tender) (ft / m)74.65 / 22.7575.17 / 22.91
Axle Loading (Maximum Weight per Axle) (lbs / kg)61,400 / 27,85163,100 / 28,622
Weight on Drivers (lbs / kg)238,300 / 108,091239,000 / 108,409
Engine Weight (lbs / kg)326,340 / 148,026325,900 / 147,826
Tender Loaded Weight (lbs / kg)222,200 / 100,788222,200 / 100,788
Total Engine and Tender Weight (lbs / kg)548,540 / 248,814548,100 / 248,614
Tender Water Capacity (gals / ML)12,000 / 45.4512,000 / 45.45
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)17.50 / 15.9017.50 / 15.90
Minimum weight of rail (calculated) (lb/yd / kg/m)99 / 49.50100 / 50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)63 / 160063 / 1600
Boiler Pressure (psi / kPa)200 / 13.80200 / 13.80
High Pressure Cylinders (dia x stroke) (in / mm)27" x 30" / 686x76227" x 32" / 686x813
Tractive Effort (lbs / kg)59,014 / 26768.3362,949 / 28553.22
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.04 3.80
Heating Ability
Firebox Area (sq ft / m2)376 / 34.94357 / 33.18
Grate Area (sq ft / m2)75 / 6.9775 / 6.97
Evaporative Heating Surface (sq ft / m2)4110 / 381.974009 / 372.58
Superheating Surface (sq ft / m2)980 / 91.081074 / 99.81
Combined Heating Surface (sq ft / m2)5090 / 473.055083 / 472.39
Evaporative Heating Surface/Cylinder Volume206.74189.05
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation15,00015,000
Same as above plus superheater percentage17,85018,150
Same as above but substitute firebox area for grate area89,48886,394
Power L115,64415,310
Power MT578.92564.90

Reference