Great Northern 4-6-2 "Pacific" Type Locomotives

Class Details by Steve Llanso

Class H-1 (Locobase 8822)

Data from GN 1-1929 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Among the first Pacifics to go into service in North America, these passenger engines had slide valves and saturated boilers in front of their Belpaire fireboxes. They had a relatively long stroke, but otherwise sat in the middle of 4-6-2s delivered with saturated boilers.

As far as Locobase can tell, these were never superheated.

Class H-2 (Locobase 8819)

Data from GN 1-1929 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection. Roster information from http://www.greatnorthernempire.net/index2.htm?GNEGNPrototypeDrawingsSteam.htm, a website authored by Ben Ringnalda.

Baldwin builders' numbers comprised:

28136, 28146, 28157-28159, 28188-89, 28203, 28207, 28229-28230, 28239-40 in May 1906; 28309, 28316-28318, 28377-78 in June; 28523 in July; and

31211-31214, 31276-77, 31301-31303, 31332-33, 31350-51, 31415, 31448 in July 1907.

The largest class of Pacifics to go into service on the GN, these had saturated boilers, slide valves, and Belpaire fireboxes as well as relatively long strokes for passenger engines. The 1425 was delivered as a trial horse for the Schmidt superheater. Like the later superheated H-4s (Locobase 146), the boiler had 160 2 1/4" small tubes and 32 l of the 5 1/2" superheater flues and was fitted with 25 1/4" cylinders.

For some reason, although most were converted to H-3 or superheated in the early teens, 10 operated into the 1930s in their original configuration. By then, their boilers had 288 tubes, were pressed to 185 psi, and had 245 sq ft of direct heating surface.

Locobases 8820-8821 show the two main variants of superheated upgrades.

Class H-2-S/H-3-S - 2 "" tubes (Locobase 8821)

Data from GN 1-1929 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Locobase 8819 shows the original H-2 Pacifics. In the early teens, most were superheated and supplied with 12" piston valves. Locobase 8820 describes the engines that had the less-drastic modification. The larger number received a new boiler to go with its Belpaire firebox, one in which the 2 1/4" tubes of the original were replaced by a larger number of 2" tubes.

In the 1920s, some were upgraded to H-3-S with a new boiler of similar dimensions in which the working pressure was raised to 210 psi. This resulted in a tractive effort of 42,900 lb.

Class H-2-S/H-3-S - 2 1/4"" tubes (Locobase 8820)

Data from GN 1-1929 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Locobase 8819 shows the original configuration of the GN's H-2 Pacifics. For most of them, it was a layout with a short life. In the early teens, most were superheated and Heron 8 1/2" piston valves installed in a universal steam chest. Later, almost all of the engines later received 12" piston valves.

This variant retained the 2 1/4" tubes ahead of their Belpaire fireboxes, but reduced the number by 122 when the shops added 30 flues. In the 1920s, some were upgraded to H-3-S with a new boiler of similar dimensions in which the working pressure was raised to 210 psi. This resulted in a tractive effort of 42,900 lb.

Class H-4 - Baldwin (Locobase 146)

Data from GN 1-1929 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection. Works numbers were 33312-33314, 33330-33332, 33343-33346, 33350-33351, 33359-33364, 33380-33381 in April 1909.

20 built by Baldwin in 1909, 25 more from Lima in 1913 (Locobase 3173). Efficient engines that ran for more than 40 years. A 14 December 1914 Railway Age article describes the road over which these engines ran, noting that one 129-mile section had a maximum grade of 1% and that the Pacifics averaged 30 mph with 11-12 cars over that section.

The class was delivered with 26" (660 mm) diameter cylinders, but was later rebuilt with the 23 1/2" cylinders shown in the specifications.

With only three exceptions, the class operated into the 1950s, with the last group of six going to the scrapper in July 1953.

Class H-4 - Lima (Locobase 3173)

Data from GN 1-1929 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection..Works numbers were 1339-1363 in 1914.

These follow-on locomotives from Lima had slightly less evaporative heating surface, slightly more superheater than the Baldwins of 1909 (Locobase 146). Lima's aspiration to enter the lists against Baldwin and Alco for main-line orders took a big step forward with this order. It was the first for the company to include as many as 25 locomotives in one purchase.

Class H-5-S (Locobase 6450)

Data from GN locomotive diagram found on Ben Ringnalda's http://www.greatnorthernempire.net/images/GNP_2523Diagram.jpg (viewed 8 Jan 2005). Many thanks to Max Magliaro who wrote Wes Barris of steamlocomotive.com concerning an unwonted lumping of the H-5-S and H-7-S classes. His questions and research resulted in Locobase splitting the record into two entries. H-7-S is found in Locobase 14987.

A long article -- http://www.gn1355.org/mechanical_attributes_of_the_h5.htm (viewed 11 July 2005) -- describes both the E-14 and the H-5 Pacific that resulted from a substantial rebuild. It is based on a reference sheet originally drafted by Doug Bemrich for the GNR Historical Society and based on research by Bemrich and Larry Obermeyer, Jr. See Locobase 8815 for a similar rebuild of J-1 & J-2 Prairies to the H-6 Pacific class.

This class was rebuilt the 1909 batch of E-14 Ten-wheelers from Baldwin to match approximately the capacity of the H-4 Pacifics (See Locobase 146 & 3173) that the Great Northern had bought before World War I. As noted in Locobases 6682 and 8844, the E-14s were produced in two quite different sizes that were the basis of each of the two Pacific rebuilds.

Compared to the earlier E-14s, the rebuilds had a much longer wheelbase under a boiler whose tubes ran 4 feet (1,219 mm) longer and noticeably higher axle loadings. (The latter improved the factor of adhesion.) The H-5-S retained the evenly spaced drivers (7 feet/2,134 mm between each two axles) and firebox dimensions as well as the power dimensions of the 1909 E-14s.

H-5-S Belpaire firebox heating surface area varied depending on fuel. Five coal burners included 31 sq ft (2.9 sq m) of arch tubes in an American Brick Arch installation. (These were road numbers 1352, 1354, 1356-1357, 1373.) The combustion chamber's area was included in the overall figure for firebox heating surface. This quintet's tenders held 19 tons (17.3 metric tons).

The oil burners were 1350-1351, 1353, 1355, 1358-1372, 1374. Of these 1350-1351 had 160 tubes, which raised tube heating surface area to 2,932 sq ft (272.4 sq m) and total heating surface area to 3,179 sq ft (295.3 sq m). Four--1350-1351, 1358-1359--also had Worthington feedwater heaters.

All H-5-S had piston valves measuring 12" (306 mm) in diameter. A Sellers Exhaust Steam Injector was part of the package.

The last 10 -- modfied in 1926-1927 and designated H-7-S -- sported a trailing-truck booster that contributed 11,700 lb to starting tractive effort. They are discussed in Locobase 14987.

The article mentioned above thoroughly describes all of the modifications and is strongly recommended. Suffice it here to say that every significant steam-producing dimension, area, or volume was enhanced beyond not only the E-14, but also the H-4 Pacific. Direct heating surface percentage of total EHS, superheater percentage of total heating surface, ratio of heating surface to cylinder volume, efficiency and maintainability of the superheater. In sum, the effort proved well worth the cost.

The rebuilding program lasted most of the 1920s. New numbers were consecutive, but did not line up with the E-14s that preceded them. After the first ten had been rebuilt in 1921-1925, the GN renumbered the class to make room for all 25.

The reconstruction proved of enduring value and very few significant changes were made to the class over the next 30 or so years of service. 1351 wrecked on 24 July 1941.

In a 20 February 2013 email to Locobase, Max Magliaro noted that the 1378 was leased by the GN in 1942 to the Spokane, Portland & Seattle as their 626. The railroad later bought the 626 outright. It was the only SP&S to use a Vanderbilt tender.

The others were sold for scrap beginning in 1950 (1), 1951 (2), 1952 (8), 1953 (7), 1954 (2), and 1955 (3). One of the class -- 1355 - was preserved as an outdoor exhibit until its restoration began at the turn of the 21st Century.

Class H-6 (Locobase 8815)

Data from GN 4 - 1946 Loco Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Turned out the Great Northern wasn't finished with some of the class of J-2 Prairies. Beginning in 1923, 15 were converted to Pacifics along the same lines as the H-5 conversions from E-14 Ten-wheelers (see Locobase 6450). The grate area in the Belpaire firebox stayed the same, although total direct heating surface increased, and the cylinders retained their long stroke.

The boilers grew through a further reduction in tube count in favor of two more flues and in the lengthening of all tubes and flues by 2 1/2 feet. Working pressure rose to 200 psi and the axle loading climbed to over 28 tons.

Class H-7-S (Locobase 14987)

Data from GN 1 - 1929 locomotive diagram supplied in May 2005 by Allen Stanley from his extensive collection. Many thanks to Max Magliaro who wrote Wes Barris of steamlocomotive.com concerning an unwonted lumping of the H-5-S and H-7-S classes. His questions and research resulted in Locobase splitting the record into entries. H-5-S is found in Locobase 6450.

Like the H-5-S, the H-7-S was a Pacific design built by Great Northern from large E-14 Ten-wheelers. The railroad's shops built two distinct Pacifics out of those earlier engines, each class based on a different Baldwin batch. The H-7-S had unevenly spaced drivers (6 1/2 feet/1,981 mm between axles 1 and 2 and 7 feet/2,134 mm between axles 2 and 3) and a longer firebox with more grate area than the H-5-S. These features were part of the 1910 order of Ten-wheelers and together with the power dimensions formed the basis of the 1926 makeover. Compared to the original Ten-wheelers, the rebuilds had a longer wheelbase and noticeably higher axle loading. (The latter improved the factor of adhesion.).

In half of the H-7-S engines, those that burned coal (1377-1381), the Belpaire firebox's heating surface area included 28 sq ft (2.9 sq m) of arch tubes in an American Brick Arch installation. The small combustion chamber's area was included in the overall figure for firebox heating surface. The oil burners (1375-1376, 1382-1384) did not have a brick arch and their tenders held 5,219 US gallons (19,754 litres). Total heating surface area 3,157 sq ft (299.3 sq m).

All ten H-7-S had 12" (305 mm) piston valves, Delta trailing trucks, and an Elesco exhaust steam injector.

Compared to the E-14 as well as the H-4 Pacific, the H-7 rebuilds, like their more numerous H-5s, gained in most areas. Direct heating surface percentage of total EHS, superheater percentage of total heating surface, ratio of heating surface to cylinder volume, efficiency and maintainability of the superheater. In sum, the effort proved well worth the cost.

The reconstruction proved of enduring value and very few significant changes were made to the class over the next 30 or so years of service.

The H-7-S were rebuilt in a second phase that began in 1926. New numbers were consecutive, but did not line up with the E-14s that preceded them.

In a 20 February 2013 email to Locobase, Max Magliaro noted that the 1378 was leased by the GN in 1942 to the Spokane, Portland & Seattle as their 626. The railroad later bought the 626 outright. It was the only SP&S to use a Vanderbilt tender.

Class H5 (Locobase 8852)

Data from GN 1916 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

This is a mystery engine, possibly a one-only conversion of an H-2. (Other H-5s were later conversions of E-14 Ten-wheelers.) The square cylinder dimensions enclosed a large volume, a spacious Belpaire firebox hosted a broad grate, and both tube sizes were substantial as well.


Specifications by Steve Llanso
ClassH-1H-2H-2-S/H-3-S - 2 "" tubesH-2-S/H-3-S - 2 1/4"" tubesH-4 - BaldwinH-4 - LimaH-5-SH-6H-7-SH5
Locobase ID8822 8819 8821 8820 146 3173 6450 8815 14987 8852
RailroadGreat Northern (GN)Great Northern (GN)Great Northern (GN)Great Northern (GN)Great Northern (GN)Great Northern (GN)Great Northern (GN)Great Northern (GN)Great Northern (GN)Great Northern (GN)
CountryUSAUSAUSAUSAUSAUSAUSAUSAUSAUSA
Whyte4-6-24-6-24-6-24-6-24-6-24-6-24-6-24-6-24-6-24-6-2
Road Numbers1400-14051406-14401408+1407, 09, 31,37,39,24+1441-14601461-14851350-13741711-17251375-1384
GaugeStdStdStdStdStdStdStdStdStdStd
BuilderAlco-RogersBurnham, Williams & CoGNGNBaldwinLimaGNGNGNGN
Year1905190619131913190919131921192319261913
Valve GearStephensonWalschaertWalschaertWalschaertWalschaertWalschaertWalschaertWalschaertWalschaertWalschaert
Locomotive Length and Weight
Driver Wheelbase12.67'13'13'13'13'13'14'13'13.50'13'
Engine Wheelbase32.17'32.17'29.87'32.17'33.75'33.75'35.95'21.50'36.95'30.75'
Ratio of driving wheelbase to overall engine wheebase 0.39 0.40 0.44 0.40 0.39 0.39 0.39 0.60 0.37 0.42
Overall Wheelbase (engine & tender)60.62'67'67'67'77.80'67.43'72.03'74.17'71.87'67.58'
Axle Loading (Maximum Weight per Axle)46333 lbs50333 lbs50333 lbs50333 lbs50666 lbs50250 lbs54666 lbs56333 lbs55500 lbs59330 lbs
Weight on Drivers139000 lbs151000 lbs151000 lbs151000 lbs152000 lbs150700 lbs176000 lbs169000 lbs166500 lbs178000 lbs
Engine Weight217000 lbs227000 lbs227000 lbs227000 lbs246350 lbs251200 lbs282800 lbs260420 lbs283400 lbs278000 lbs
Tender Light Weight148000 lbs148200 lbs152200 lbs148200 lbs197300 lbs163100 lbs188400 lbs188400 lbs185000 lbs166000 lbs
Total Engine and Tender Weight365000 lbs375200 lbs379200 lbs375200 lbs443650 lbs414300 lbs471200 lbs448820 lbs468400 lbs444000 lbs
Tender Water Capacity7000 gals8000 gals8000 gals8000 gals10000 gals8000 gals10000 gals10000 gals10000 gals8000 gals
Tender Fuel Capacity (oil/coal)14 tons13 tons13 tons13 tons19 tons15 tons4500 gals4600 gals20 tons15 tons
Minimum weight of rail (calculated) on which locomotive could run77 lb/yard84 lb/yard84 lb/yard84 lb/yard84 lb/yard84 lb/yard98 lb/yard94 lb/yard93 lb/yard99 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter73"69"69"69"73"73"73"69"73"73"
Boiler Pressure200 psi210 psi210 psi185 psi210 psi210 psi210 psi200 psi210 psi180 psi
Cylinders (dia x stroke)21" x 28"22" x 30"23.5" x 30"23.5" x 30"23.5" x 30"23.5" x 30"23.5" x 30"23.5" x 30"23.5" x 30"28" x 28"
Tractive Effort28756 lbs37563 lbs42859 lbs37757 lbs40511 lbs40511 lbs40511 lbs40818 lbs40511 lbs46009 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.83 4.02 3.52 4.00 3.75 3.72 4.34 4.14 4.11 3.87
Heating Ability
Firebox Area234.60 sq. ft206 sq. ft242 sq. ft242 sq. ft245 sq. ft234 sq. ft247 sq. ft246 sq. ft300 sq. ft247 sq. ft
Grate Area49.17 sq. ft54.15 sq. ft54.15 sq. ft54.15 sq. ft58.07 sq. ft53.40 sq. ft50.40 sq. ft55 sq. ft55 sq. ft61.50 sq. ft
Evaporative Heating Surface3476 sq. ft3914 sq. ft3234 sq. ft3066 sq. ft3177 sq. ft3104 sq. ft3130 sq. ft3069 sq. ft3185 sq. ft4117 sq. ft
Superheating Surface775 sq. ft775 sq. ft641 sq. ft670 sq. ft774 sq. ft775 sq. ft774 sq. ft900 sq. ft
Combined Heating Surface3476 sq. ft3914 sq. ft4009 sq. ft3841 sq. ft3818 sq. ft3774 sq. ft3904 sq. ft3844 sq. ft3959 sq. ft5017 sq. ft
Evaporative Heating Surface/Cylinder Volume309.68296.54214.74203.58210.95206.11207.83203.78211.48206.31
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation9834113721137210018121951121410584110001155011070
Same as above plus superheater percentage9834113721353212021142681323312701132001386013063
Same as above but substitute firebox area for grate area46920432606047653724601975798562244590407560052463
Power L11007890461831115894172551748119223172181976614763
Power MT479.53396.22802.03696.16750.80767.20722.38673.83785.16548.54

Photos

Reference

Credits

Introduction and roster provided by Richard Duley. Class details and specifications provided by Steve Llanso of Sweat House Media.