EMD SW1 explained

EMC/EMD SW1
Powertype:Diesel-electric
Builder:General Motors Electro-Motive Corp (later Division) (EMC/EMD)
Buildmodel:SW1
Builddate:
Totalproduction:661
Aarwheels:B-B
Trucks:AAR Type A or B
Wheeldiameter:40inches
Minimumcurve:57° (104.79abbr=onNaNabbr=on)
Wheelbase:302NaN2
Length:44feet
Width:102NaN2
Height:14feet
Locoweight:196000lb
Primemover:EMD 6-567B or 6-567A or 6-567AC
Enginetype:V6 2-stroke diesel
Aspiration:Gear-driven Roots blower
Displacement:3402cuin
Cylindercount:6
Cylindersize:NaNx
Gear Ratio:62:15
Maxspeed:65abbr=on0abbr=on
Poweroutput:600abbr=on0abbr=on
Generator:GM D-4
Tractionmotors:(4) GM D-7A
Tractiveeffort:49000lb
Locale:United States
Mexico

The EMD SW1 is a 600hp diesel-electric switcher locomotive built by General Motors' Electro-Motive Corporation (later Division) between December 1938 and November 1953. Final assembly was at EMD's plant at LaGrange (McCook) Illinois. The SW1 was the second generation of 3402cuin switcher from EMD, succeeding the SC (cast frame) and SW (welded frame). The most significant change from those earlier models was the use of an engine of EMD's own design, the then-new 567 engine, here in 600hp V6 form. 661 locomotives of this design were built,[1] with a gap in production between March 1943 and September 1945 due to World War II.

The SW1 was the start of a long line of SW series switchers produced by EMD. It was complemented by the SW7 in 1949 and the SW8 in 1950. SW1 production ceased in November 1953, with its replacement, the equally powerful SW600, starting production in February 1954.

Locomotive name

EMD arrived at the name SW1 based on the locomotive's power (S for 600 hp) and frame design (W for welded), and the number 1 was added to distinguish the new design from the previous EMD SW. As new and more powerful SW designs emerged in the 1950s, the SW name evolved to instead stand for "switcher."

Engine and powertrain

The SW1 introduced a 6-cylinder version of the 567 (later 567A) series engine to EMC/EMD switchers. Developing 600hp at 800 rpm, this engine remained in production until 1966. Designed specifically for railroad locomotives, this was a mechanically-aspirated, two-stroke, 45 degree V type, with an NaNby, bore by stroke, giving 567cuin displacement per cylinder. A direct current generator provides power to four traction motors, two on each truck, in a B-B arrangement. The SW1, like most EMD switchers, uses the AAR type A switcher truck. EMC/EMD had built all its components since 1939.[2] [3]

Production changes

Several changes were made to the SW1 over its production life. Internally, the post-war locomotives used the 567A engine.

Externally, the two center cab windows over the hood, which were curved to follow the roofline originally, became flat-topped after mid-1950. Another external difference is the taper of the hood to the cab, which was a two-stage taper in earlier units but became a single taper in later production. Very early locomotives were delivered with a stubby exhaust stack, but this did not lift the diesel exhaust sufficiently clear of crew visibility. All later units were delivered with EMD's standard conical switcher stack, while early units were generally modified with taller stacks too. Early locomotives had a single large headlight, while later had twin sealed-beam headlights.[4]

Original owners

Railroad Quantity Road numbers Notes
1 101
1 8
1 10
1 9
1 1901 Rejected, to Richmond Terminal Railroad #1
16 200–215
  1. 208, B&O renumbered to #8408, is currently owned by Wilmington & Western Railroad. 2nd oldest SW1 in routine scheduled service.
6 216-221
24 1109–1132 1109 owned by RMNE. Thomaston, CT 1113 owned and operated by BSRM, Adams/Lenox, MA. 1127 preserved by the Danbury Railway Museum in Danbury, CT.
1 400
1 42
5 21–25
1 1
3 2, 3, 7
4 1109–1112
1 4
5 95–99 99 to MP 6001, now Dardanelle & Russellville 16
20 1207–1212, 1214, 1215,
1268–1279
2 3, 4
2 200–201
18 9136–9153
3 DS-50, 5, 6 DS-50 renumbered to 1
25 1610–1634 renumbered
1 55
1 500 only SW1 exported
1 2 built with a 567AC engine. Last SW1 built.
6 10–15
6 60–65
11 427–437
3 210–212
2 900–901 re-engined with 8-567B 800 hp engines, new hoods 1952. Reclassified SW8.
1 1
27 220–246
EMD (demonstrator units)* 7 755, 804, 905, 906,
911, 700, 152
EMC 755 was the first SW1
1 360
2 602, 604
1 1
5 201–205 201 to Dardanelle & Russellville 15
1 201
3 70–72
1 1
2 600–601
14 12, 14–18, 22,
30, 31, 33–36, 38
9 5101–5105, 80–83 5101–5105 renumbered to 75-79. Then to Burlington Northern 75-83. 77 was sold to Walla Walla Valley in 1975.
1 61
3 14–16
1 10
19 9014–9032
12 54, 57, 70–73, 76–81
1 5
6 112–115, 118-119
  1. 114 is currently owned by Wilmington & Western Railroad. Oldest SW1 in routine scheduled service.
1 11
5 11–15
1 6
1 70
2 1–2
3 3–5
1 10
3 1–3
10 9004–9006, 9011, 9200–9205
1 15
103 600–621 (first), 622–654,
574–599, 600–621 (second)
9 (2nd) is now WRIX 1001, located on RVT - White City, OR0
2 105–106
  1. 106 is now Independent Locomotive Services #920
85 5910, 5944–5953, 5987–5999,
9104, 9137–9154, 9200–9203,
9205-9209, 9396–9428
2 10–11
1 A
9 212–218, 220, 221
3 9–11
Portland Traction Company (Oregon) 2 100, 200 100 is currently owned, restored to as delivered and operated by Oregon Pacific Railroad on its original home rails.
9 16–24
22 50–54, 300–306, 340–341,
352, 370–372, 890–891, 893–894
18 529–546 536 operational as AOK 536. Serial number 1685 build 4/42
1 100
1 (no numbers)
1 1200
1 320
9 2002–2004, 2007–2011, 8565
15 11, 1000, 1004–1016 11 is Texas & New Orleans
1 12
2 1–2
4 1000–1003
8 501–508
22 455–476
US Department of Defense (US Army) 4 7001–7004 to Alaska 1203, 1201-1202, 1204
11 101–111 Two units acquired by Tulsa-Sapulpa Union Railway, now in service as Numbers 101 & 102.[5]
1 15
2 502–503 WP 501 was ex-EMC 906
4 1001–1004
Total 661

Preservation

See also

References

Notes and References

  1. Book: Schafer, Mike. Vintage diesel locomotives. 1998. Motorbooks International. 0-7603-0507-2. Osceola, WI. 22–25. 38738930.
  2. Book: Pinkepank, Jerry A. The Second Diesel Spotter's Guide. 1973. Kalmbach Books. 66-22894. 10, 26, 35.
  3. Book: David. Ross. The Encyclopedia of Trains and Locomotives. 2003. 978-0-7607-9679-5. 264. Barnes & Noble .
  4. Book: Pinkepank, Jerry A. The Second Diesel Spotter's Guide. 1973. Kalmbach Books. 66-22894. 35.
  5. Web site: Tulsa-Sapulpa Union Railway. American-Rails.com. June 24, 2021.
  6. Web site: SWITCH LOCOMOTIVE - govdeals.com. 2021-07-10. www.govdeals.com. en.
  7. Web site: Pictures of BDTL 98 . RR Picture Archives . 11 August 2023.
  8. Web site: Franz . Justin . 2024-04-04 . Boston & Maine SW1 Destined for Danbury . 2024-07-14 . Railfan & Railroad Magazine . en-CA.
  9. Web site: Rolling Stock of the Utah State Railroad Museum: Cargill 6751: SW1 . Utah State Railroad Museum: Spencer S. Eccles Rail Center . Union Station . Ogden, Utah . 2016 . 2017-01-27 . dead . https://web.archive.org/web/20170127182009/http://theunionstation.org/museums/utah-state-railroad-museum/spencer-s-eccles-rail-center/ . 2017-01-27 .
  10. Book: Harwood, Herbert Hawley Jr. . Rails to the Blue Ridge: The Washington and Old Dominion Railroad, 1847–1968. Fairfax Station, Virginia. Northern Virginia Regional Park Authority. 3rd. 2000. 137. 0615114539. 44685168. Google Books. .
  11. Web site: Home . montevideomrhc.org.
  12. Web site: Museum Projects. www.lynnvillecoalmuseum.org. 2017-02-25.
  13. Web site: Home . oerm.org.