Jump to content

Union Pacific class MK-1

From Wikipedia, the free encyclopedia
Union Pacific class MK-1
2111 in the snow in Idaho in the 1930s
Type and origin
Power typesteam [1]
BuilderBaldwin Locomotive Works
Build date1910-1911
Total produced86
Specifications
Configuration:
 • Whyte2-8-2
Gauge4 ft 8+12 in (1,435 mm)
Leading dia.30½"
Driver dia.57"
Trailing dia.36"
Wheelbase:
 • Engine34 ft 8 in
 • Drivers16 ft
 • incl. tender64 ft 7 in
Axle load:
 • Leading24,100 lb
 • Trailing34,550 lb
Adhesive weight204,450 lb
Loco weight263,100 lb
Tender typeVanderbilt tender in later batches[2]
Fuel typelignite
Fuel capacity10 tons
Water cap.9,000 US gallons
Firebox:
 • Grate area70 sq ft
Boiler:
 • Tube plates20 ft 6 in
 • Small tubes495× 2"
Boiler pressure180 psi
Heating surface:
 • Firebox267 sq ft
 • Tubes5,292 sq ft
 • Total surface5,559 sq ft
Cylinders2
Cylinder size23¾" × 30"
Valve gearWalschaerts
Performance figures
Tractive effort45,300 lbf
Career
ClassUP: MK-1
Numbers1900-1929, 2000-2014, 2100-2140[3]
PreservedNo. 2005
DispositionOne preserved, remainder scrapped

The Union Pacific class MK-1 was a class of 2-8-2 'Mikado' type steam locomotives that were built by the Baldwin Locomotive Works originally for the Oregon Railroad and Navigation Company (OR&N),[4] Oregon Short Line Railroad (OSL)[2] and Union Pacific Railroad (UP) in 1910 and 1911.[2]

History

[edit]

In 1910, the Oregon-Washington Railroad and Navigation Company (OWR&N) purchased a 2-8-2 'Mikado' locomotive from the Baldwin Locomotive Works and had this single locomotive numbered 440,[4] this locomotive would be renumbered as 500 in 1911, and renumbered to 2100 in 1915.

In 1911, the OWR&N would order another 40 of these locomotives from Baldwin where they were originally numbered as 501–540, but renumbered as 2101–2140. The Oregon Short Line Railroad (OSL) would order 15 locomotives from Baldwin and numbered them as 1100–1114, but renumbering them to 2000–2014 in 1915.[2] The Union Pacific Railroad (UP) would order 30 locomotives from Baldwin where they numbered them as 500–529, renumbering them to 1900–1929 in 1915

OSL No. 2000 was sold to the Spokane International Railroad (SI) in 1947.[5]

Design

[edit]

The locomotives were designed from the outset to burn low-quality lignite coal as a fuel. In general they followed typical practice of the day for Baldwin designs and locomotives for Harriman's Associated Lines, but with some changes to the boiler and firebox.[1] The boiler was cylindrical and the firebox was stayed with 400 radial rod stays, rather than girder crown stays. Given the poor quality of the fuel, a larger boiler was needed than usual for the power of the locomotive. The heating surface of 5,559 sq ft considerably exceeded that of the nearest comparable design, with 4,466.[i] The grate bars were arranged as large cast grate sections spanning half the width of the firebox and arranged for rocking to clear ash. Airflow was provided by an unusually large number of narrow slots, to suit lignite.[7] The brick arch was deeper than usual, again to suit lignite, and was supported by four arch tubes. The boiler, as built, was unsuperheated and had 495× 2" tubes.[1]

At the time this was the largest Mikado built, although not quite the most powerful or with the most weight on its drivers.[1][6]

Superheating

[edit]

In 1912, the boiler was rebuilt to provide superheating. Half of the tubes were removed in favour of 36 larger flues containing superheater elements. Total heating area was reduced to 5,118 sq ft, although still large in its class.[i][2]

Oil firing

[edit]

Some were later converted to oil firing.[2]

Preservation

[edit]

Only one member of the class is in preservation, No. 2005, which is on static display at Ross Park based in Pocatello, Idaho.[2]

Fleet numbers

[edit]

Union Pacific

[edit]
Extended content
Road number Built date Serial number First run date Retirement date Disposal date Notes
1900 1911 - - - - Scrapped
1901 1911 - - - - Scrapped
1902 1911 - - - - Scrapped
1903 1911 - - - - Scrapped
1904 1911 - - - - Scrapped
1905 1911 - - - - Scrapped
1906 1911 - - - - Scrapped
1907 1911 - - - - Scrapped
1908 1911 - - - - Scrapped
1909 1911 - - - - Scrapped
1910 1911 - - - - Scrapped
1911 1911 - - - - Scrapped
1912 1911 - - - - Scrapped
1913 1911 - - - - Scrapped
1914 1911 - - - - Scrapped
1915 1911 - - - - Scrapped
1916 1911 - - - - Scrapped
1917 1911 - - - - Scrapped
1918 1911 - - - - Scrapped
1919 1911 - - - - Scrapped
1920 1911 - - - - Scrapped
1921 1911 - - - - Scrapped
1922 1911 - - - - Scrapped
1923 1911 - - - - Scrapped
1924 1911 - - - - Scrapped
1925 1911 - - - - Scrapped
1926 1911 - - - - Scrapped
1927 1911 - - - - Scrapped
1928 1911 - - - - Scrapped
1929 1911 - - - - Scrapped
2000 April 1911 - - - - Sold to the Spokane International Railroad in 1947.[5] Scrapped
2001 1911 - - - - Scrapped
2002 1911 - - - - Scrapped
2003 1911 - - - 1952 Scrapped
2004 1911 - - - - Scrapped
2005[2] April 1911 36367 - 1958 - On static display at the Ross Park in Pocatello, Idaho.
2006 1911 - - - - Scrapped
2007 1911 - - - - Scrapped
2008 1911 - - - - Scrapped
2009 1911 - - - - Scrapped
2010 1911 - - - - Scrapped
2011 1911 - - - - Scrapped
2012 1911 - - - - Scrapped
2013 1911 - - - - Scrapped
2014 1911 - - - - Scrapped
2100 1910 - - - 1955 Scrapped
2101 1911 - - - - Scrapped
2102 1911 - - - - Scrapped
2103 1911 - - - 1951 Scrapped
2104 1911 - - - - Scrapped
2105 1911 - - - - Scrapped
2106 1911 - - - - Scrapped
2107 1911 - - - - Scrapped
2108 1911 - - - - Scrapped
2109 1911 - - - - Scrapped
2110 1911 - - - - Scrapped
2111 1911 - - - - Scrapped
2112 1911 - - - - Scrapped
2113 1911 - - - - Scrapped
2114 1911 - - - - Scrapped
2115 1911 - - - - Scrapped
2116 1911 - - - - Scrapped
2117 1911 - - - - Scrapped
2118 1911 - - - - Scrapped
2119 1911 - - - - Scrapped
2120 1911 - - - - Scrapped
2121 1911 - - - - Scrapped
2122 1911 - - - - Scrapped
2123 1911 - - - - Scrapped
2124 1911 - - - - Scrapped
2125 1911 - - - - Scrapped
2126 1911 - - - - Scrapped
2127 1911 - - - - Scrapped
2128 1911 - - - - Scrapped
2129 1911 - - - - Scrapped
2130 1911 - - - - Scrapped
2131 1911 - - - - Scrapped
2132 1911 - - - - Scrapped
2133 1911 - - - - Scrapped
2134 1911 - - - - Scrapped
2135 1911 - - - - Scrapped
2136 1911 - - - - Scrapped
2137 1911 - - - - Scrapped
2138 1911 - - - - Scrapped
2139 1911 - - - - Scrapped
2140 1911 - - - - Scrapped

References

[edit]
  1. ^ a b c d "Powerful Lignite Burner of the Mikado Type". American Engineer and Railroad Journal: 404–406. October 1910.
  2. ^ a b c d e f g h "Union Pacific #2005".
  3. ^ McCullough, Gordon. "UPRR Steam Locomotive Roster by Class and Number" (PDF). Union Pacific Historical Society. Retrieved 2024-09-22.
  4. ^ a b "Simple 2-8-2 for the Oregon Railroad Navigation Co". Railroad and Locomotive Engineering. 23 (10): 417–418. October 1910.
  5. ^ a b Jones, Dale W. (2019). Spokane International Railway. Arcadia Publishing. p. 76. ISBN 978-1-4671-0299-5.
  6. ^ a b "Mikado Type Freight Locomotive: Virginian Railway". American Engineer and Railroad Journal: 225–229. June 1909.
  7. ^ "Burning Lignite Coal In Locomotives". American Engineer and Railroad Journal: 161–163. May 1908.