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
Class H-1 H-2 H-2-S/H-3-S - 2 "" tubes H-2-S/H-3-S - 2 1/4"" tubes H-4 - Baldwin H-4 - Lima H-5-S H-6 H-7-S H5
Locobase ID 8822 8819 8821 8820 146 3173 6450 8815 14987 8852
Railroad 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) Great Northern (GN)
Whyte 4-6-2 4-6-2 4-6-2 4-6-2 4-6-2 4-6-2 4-6-2 4-6-2 4-6-2 4-6-2
Road Numbers 1400-1405 1406-1440 1408+ 1407, 09, 31,37,39,24+ 1441-1460 1461-1485 1350-1374 1711-1725 1375-1384
Gauge Std Std Std Std Std Std Std Std Std Std
Builder Alco-Rogers Burnham, Williams & Co GN GN Baldwin Lima GN GN GN GN
Year 1905 1906 1913 1913 1909 1913 1921 1923 1926 1913
Valve Gear Stephenson Walschaert Walschaert Walschaert Walschaert Walschaert Walschaert Walschaert Walschaert Walschaert
Locomotive Length and Weight
Driver Wheelbase 12.67' 13' 13' 13' 13' 13' 14' 13' 13.50' 13'
Engine Wheelbase 32.17' 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 lbs 50333 lbs 50333 lbs 50333 lbs 50666 lbs 50250 lbs 54666 lbs 56333 lbs 55500 lbs 59330 lbs
Weight on Drivers 139000 lbs 151000 lbs 151000 lbs 151000 lbs 152000 lbs 150700 lbs 176000 lbs 169000 lbs 166500 lbs 178000 lbs
Engine Weight 217000 lbs 227000 lbs 227000 lbs 227000 lbs 246350 lbs 251200 lbs 282800 lbs 260420 lbs 283400 lbs 278000 lbs
Tender Light Weight 148000 lbs 148200 lbs 152200 lbs 148200 lbs 197300 lbs 163100 lbs 188400 lbs 188400 lbs 185000 lbs 166000 lbs
Total Engine and Tender Weight 365000 lbs 375200 lbs 379200 lbs 375200 lbs 443650 lbs 414300 lbs 471200 lbs 448820 lbs 468400 lbs 444000 lbs
Tender Water Capacity 7000 gals 8000 gals 8000 gals 8000 gals 10000 gals 8000 gals 10000 gals 10000 gals 10000 gals 8000 gals
Tender Fuel Capacity (oil/coal) 14 tons 13 tons 13 tons 13 tons 19 tons 15 tons 4500 gals 4600 gals 20 tons 15 tons
Minimum weight of rail (calculated) on which locomotive could run 77 lb/yard 84 lb/yard 84 lb/yard 84 lb/yard 84 lb/yard 84 lb/yard 98 lb/yard 94 lb/yard 93 lb/yard 99 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter 73" 69" 69" 69" 73" 73" 73" 69" 73" 73"
Boiler Pressure 200 psi 210 psi 210 psi 185 psi 210 psi 210 psi 210 psi 200 psi 210 psi 180 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 Effort 28756 lbs 37563 lbs 42859 lbs 37757 lbs 40511 lbs 40511 lbs 40511 lbs 40818 lbs 40511 lbs 46009 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 Area 234.60 sq. ft 206 sq. ft 242 sq. ft 242 sq. ft 245 sq. ft 234 sq. ft 247 sq. ft 246 sq. ft 300 sq. ft 247 sq. ft
Grate Area 49.17 sq. ft 54.15 sq. ft 54.15 sq. ft 54.15 sq. ft 58.07 sq. ft 53.40 sq. ft 50.40 sq. ft 55 sq. ft 55 sq. ft 61.50 sq. ft
Evaporative Heating Surface 3476 sq. ft 3914 sq. ft 3234 sq. ft 3066 sq. ft 3177 sq. ft 3104 sq. ft 3130 sq. ft 3069 sq. ft 3185 sq. ft 4117 sq. ft
Superheating Surface 775 sq. ft 775 sq. ft 641 sq. ft 670 sq. ft 774 sq. ft 775 sq. ft 774 sq. ft 900 sq. ft
Combined Heating Surface 3476 sq. ft 3914 sq. ft 4009 sq. ft 3841 sq. ft 3818 sq. ft 3774 sq. ft 3904 sq. ft 3844 sq. ft 3959 sq. ft 5017 sq. ft
Evaporative Heating Surface/Cylinder Volume 309.68 296.54 214.74 203.58 210.95 206.11 207.83 203.78 211.48 206.31
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation 9834 11372 11372 10018 12195 11214 10584 11000 11550 11070
Same as above plus superheater percentage 9834 11372 13532 12021 14268 13233 12701 13200 13860 13063
Same as above but substitute firebox area for grate area 46920 43260 60476 53724 60197 57985 62244 59040 75600 52463
Power L1 10078 9046 18311 15894 17255 17481 19223 17218 19766 14763
Power MT 479.53 396.22 802.03 696.16 750.80 767.20 722.38 673.83 785.16 548.54

Photos

Reference

Credits

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

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