User:Hachijo8/MR250

From Wikipedia, the free encyclopedia
Manila Railroad 250 class
Type and origin
Power typeSteam
DesignerH.K. Porter, Inc.
Eddystone Arsenal
BuilderBaldwin Locomotive Works
Order number60515, 60540-42, 600581-84
Build date1921-22
Total produced8
Specifications
Configuration:
 • Whyte2-8-2
 • UIC1'D1'h3P
Gauge3 ft 6 in (1,067 mm)
Driver dia.48 in (1,200 mm)
Wheelbase
 • Engine27.58 ft (8.41 m)
 • Drivers13.25 ft (4.04 m)
Adhesive weight102,000 lb (46 t; 46,000 kg)
Loco weight143,000 lb (65 t; 65,000 kg)
Tender weight117,500 lb (53.3 t; 53,300 kg)
Total weight260,500 lb (118.2 t; 118,200 kg)
Fuel typeCoal, oil
Fuel capacity6,000 US gal (23,000 L) oil or 6 t (13,000 lb) coal
Water cap.6,000 US gal (23,000 L)
Firebox:
 • Type
 • Grate area32 sq ft (3.0 m2)
Boiler pressure180 psi (1,200 kPa)
Heating surface:
 • Firebox176 sq ft (16.4 m2)
 • Tubes416 sq ft (38.6 m2)
 • Flues498 sq ft (46.3 m2)
 • Tubes and flues914 sq ft (84.9 m2)
 • Total surface
Superheater:
 • TypeWorthington No. 1 heater
 • Heating area435 sq ft (40.4 m2)
Cylinders3
Cylinder size20 in (510 mm) diameter x 28 in (710 mm) stroke
Valve gearWalschaerts
Valve typePiston valves
CouplersBuffers and chain coupler
Performance figures
Maximum speed53 mph (85 km/h)
Power output1,372 hp (1,023 kW)
Tractive effort42,840 lbf (190.6 kN)
Factor of adh.2.78
Career
OperatorsManila Railroad Company
Number in class8
Numbers251-258
LocaleEntire MRR network
DeliveredAugust 1928
First run1929
Preserved0
Scrappedc. 1945
DispositionScrapped
References:[1]

The Manila Railroad 250 class were eight 2-8-2 Mikado-type steam locomotives. They were built by Baldwin Locomotive Works in 1928 for the Manila Railroad, predecessor of the Philippine National Railways.

Background[edit]

The early 1920s saw popular American manufacturers enter the Philippine market as part of the policy of the newly-reorganized Manila Railroad. Both H.K. Porter, Inc. and American Locomotive Company (Alco) built locomotives for the Manila Railroad. The locomotives enjoyed popularity among railroad engineers for much of the interwar period that the British-built locomotives were almost immediately retired from service. In the late 1920s, the Manila Railroad also ordered locomotives from Baldwin Locomotive Works. This became the Manila Railroad 140 class.

Despite being the first locomotives built by Baldwin, the 140 class was based on a design created by competing H.K. Porter. After replicating the success of the Porter design during its first runs between 1927 and 1928, a four-axle version was ordered. This became the 250 class.

Design[edit]

The design of the 250 class was based on the 140 class, and was modified by Baldwin subsidiary Eddystone Arsenal. Like the Alco-built 170 and 200 classes, the 140 and 250 classes were built with a majority of the locomotive having similar (and therefore interchangeable) parts. The tubes, flukes, cylinders, piston valves, arch tubes, among other specifications, were made similar to those of the 140 class. However, the piston valves had a lengthened stroke while the driver diameter was shrank to 45 in (1,100 mm) from 54 in (1,400 mm). This was done to achieve a higher tractive effort.

Service[edit]

The 250 class entered service in 1929. However, the 250 class did not have as much documentation as its Pacific-type sister class and information regarding them was scarce. It remains unknown when exactly the 250 class locomotives were decommissioned, presumably before all steam locomotives were retired from mainline service on August 15, 1956. With all steam locomotives of the Manila Railroad era being extinct, the class was eventually scrapped after its retirement.

  1. ^ Llanso, Steve. "Manila Railroad 2-8-2 Locomotives in [the] Philippines". SteamLocomotive.com. Sweat House Media. Retrieved January 30, 2021.