Paris-Orleans 4-6-0 Locomotives in France

Class 1701 (Locobase 3913)

Data taken from table published in Edouard Sauvage, "Four-Cylinder Compound Locomotives of France", Railroad Gazette, Volume XXXII, No 30 (28 September 1900), pp. 629-632, which was compiled through direct communications with the various designers; and "230 n° 1 701 à 1 725 du PO", on the WikiPO at [], last accessed 3 November 2024. Société Métallurgique Tubize produced the first ten (1178-1187 in 1899), Société de Saint-Léonard followed with nine more, and Société de Haine Saint-Pierre completed with six more (works numbers 632-637 in 1899).

The PO's 25 Ten-wheelers had dimensions virtually identical with a series of Sud engines built around the same time as well as a 25-engine batch for the Est. They burned their coal in Belpaire square-shouldered fireboxes.

The only difference between the PO engines and those of the Sud was in a slight reduction in the number of large-diameter Serve internally finned boiler tubes. The

The last six delivered to the PO trailed slightly larger tenders carrying another 1,000 litres (264 US gallons) of water. Empty weight increased to 18,200 kg (40,124 lb) and loaded weight rose to 38,000 kg (85,539 lb).

Class 171S/230 151/230 K and F (Locobase 21222)

Data from "230 n° 171 S vers 257 S du PO" on the WikiPO at [], last accessed 16 November 2024; and Jean Falaize and Henri Girod-Eymery, A Travers Les Chemins de Fer d'le origine a nos jours (Paris: Editions Denoel, 1947), p. 5. (Thanks to Alexander Blessing for his 15 October 2024 email suggesting that Locobase add this entry and supplying details from WikiPO.)

Forquenot's 2-4-2 designs dominated express passenger trains in the 1870s-1890s with the 1873 171 class (Locobase 618) contributing 87 locomotives to the swarm. Of all the "Columbia" type engines to be modified by the PO's Ivry shops, this class almost certainly emerged as the most transformed. Indeed, Locobase wonders what could possibly have remained from the original locomotive. Over the three years from 1911-1913, the following 171s entered service: 171 S, 172 S, 175 S, 176 S, 178 S, 180 S, 181 S, 182 S, 183 S, 185 S, 186 S, 188 S, 189 S, 190 S, 191 S, 201 S, 206 S, 210 S, 214 S, 215 S, 223 S, 224 S, 226 S, 227 S, 232 S, 233 S, 234 S, 235 S, 236 S, 240 S, 241 S, 247 S, 248 S, 257 S.

The nearly 35 years that had passed before Ivry delivered the first engines saw a number of key changes in locomotive design. One was the adoption of Belpaire's square-shouldered firebox and large grate. 64 Serve tubes--70-mm (2.76") tubes whose eight 3.5 mm (1/8") internal longitudinal fins--significantly enhanced heating surface area occupied the boiler along with 20 50-mm (1.97") smoothbore tubes, and 21125-mm (5.1") flues holding superheater elements.Even more fundamental, a good-sized superheater created drier steam than a similar saturated boiler. Piston valves handled the hotter steam.

171S tenders seem small and the three axles were divided into a single axle just behind the drawbar and a tightly spaced bogie containing an equalized pair of rear axles.

The makeover proved long-lasting. As late as 1947, 33 of the class (then designated 230 F) appeared on the roster. A photo shows that they now bore small smoke-lifters mounted on the running board outside of the smokebox.

Class 1771 (Locobase 12409)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 23, p. 15. See also the French National Railway Museum at Mulhouse and its online site: []

Works numbers were 17724-17730, 17751-17758, 17797 in May 1900; 17798-17801, 17842-17845, 17858-17863 in June.

These apparently orthodox Ten-wheelers were delivered with 10" piston valves.

The Mulhouse entry discussing among other topics superheating French locomotives notes that it was one of the "Chicagos" (or so this class was known on the P-O) that first tested a superheater installation for a French railway.

Class 230 S (Locobase 21184)

Data from "230 n° 4 004 S et 4 034 S du PO" in WikiPO at [], last accessed 22 June 2024.

All of the 64 four-cylinder de Glehn compound 230s (4-6-0 or Ten-wheelers) supplied by SACM in 1903 (Locobase 10358) were delivered with saturated boilers. In 1925, SACM updated the design with a superheater. (As of 1918, the SACM's home in Alasace-Lorraine had been returned to France after nearly 50 years of German occupation.)

The modifications didn't amount to a substantially changed design. In addition to adding a sizable four-pass superheater, its builder fitted a fast-acting, high-pressure Westinghouse brake system. Otherwise, the locomotives retained their Belpaire fireboxes and Serve tubes.

As Pacifics had already superseded the 4001s in express passenger service, the need for superheated Ten-wheelers on the PO never seemed to be necessary and these two were the only ones that entered service in 1925. See Locobase 21185 for the lone Schnedier-modified 4062 S.

Class 230 S (Locobase 21185)

Data from "230 n° 4 062 S du PO" in WikiPO at [], last accessed 22 June 2024.

As noted in Locobase 21084, all of the 64 four-cylinder de Glehn compound 230s (4-6-0 or Ten-wheelers) supplied by SACM in 1903 (Locobase 10358) were delivered with saturated boilers. In 1925, SACM updated the design with a superheater. The first two came from SACM in 1925. Apparently, the PO wanted to compare that makeover to Schneider's somewhat smaller installation.

Again as described in 21184, the modifications didn't amount to a substantially changed design. In addition to adding a superheater, Schneide fitted a fast-acting, high-pressure Westinghouse brake system. Otherwise, the locomotives retained their Belpaire fireboxes and Serve tubes.

Whatever the results of the comparison between the two superheated variants, the lack of a need for express passenger 4-6-0s on the PO doomed this engine to be unique.

Class 4001 (Locobase 10538)

Data from "Compound Locomotive, Paris-Orleans Railway", The Locomotive Magazine,Vol XI (15 December 1905), p. 207; and at [], last accessed 20 June 2024.. See also M P Gonte, "Four-cylinder Compound Locomotives on the Paris-Orleans Railways", Railroad Gazette, Volume XXXIX [39], No 4 (28 July 1905), pp. 91-92 (Original article published in La Revue Generale, July 1904-translated by Baldwin's Lawford H. Fry.)

"The excellent service furnished by this class of engines is well known." says the LM report, which seized the opportunity offered by the Liege Exposition to talk about this four-cylinder de Glehn compound. "On the line from Paris to Tours trains of 350 tons are hauled at a mean speed of 55 miles [90 kph] per hour, and an engine of this type has without any difficulty taken a train of 492 tons at an average speed of 48 miles per hour. [75 kph]"

The particular utility of the six-coupled engines in this service was their ability to handle very heavy express and passenger trains while making frequent stops. They were fitted with rather large boilers, internally finned Serve firetubes, and Belpaire fireboxes, although the total direct heating surface was not exceptionally big. Beginning with 4016, the frame forward was about 6" (152 mm) longer.

The first 26 used tenders carrying 4,200 lb of fuel. Tenders behind the last 59 offered 6,000 lb.

Locobase 10539 shows the 20 locomotives built by Baldwin to French specifications in 1907; they were the last locomotives of this class.

Class 4065 (Locobase 10539)

Data from "DeGlehn Four Cylinder Compound Locomotive", Railway Master Mechanic,Volume XXXI [31] (August 1907), p. 280-282; and DeGolyer, Volume 30, p. 38+. Works numbers were 30754-30755, 30792, 30805-30806, 30893-30897, 30951-30953, 30972-30978. Thanks to Alexander Blessing for his 16 June 2024 email pointing the proper class ID and using the WikiPO information to note the difference between Baldwin's specs and the railways figures.)

Essentially identical to the French-built Ten-wheelers (Locobase 10538) that first rolled out in 1903.

Some notes in the Baldwin specifications indicates the level of caution on the P-O's part about American construction methods: "Frames perfectly fitted, especially in the box, guides, cyl[inde]r supports and braces ...The parallelism of axles will not be obtained by shims of unequal thickness either in box guides or boxes."

(Another possibility is that the P-O was too aware of French methods and wanted to forestall such lackadaisical solutions. Locobase has no evidence to support either conjecture, so just sayin'.)

Class Series 4201 / 230 G 201 (Locobase 1487)

Data from Collection Henri-Marie Petiet (HMP)

ClichT de trains pris a +tampes 1943-1946, [] . See also "New Locomotives for the Paris-Orleans Railway: Constructed by the North British Locomotive Co, Ltd," Locomotive Magazine Volume XXIII [23], No 296 (16 April 1917), p. 63. Produced by SACM, Batignolles, and the North British Locomotive Company.

Built over an eight-year period from 1914 to 1922 (although few were produced during World War One), the 170-odd engines served well for decades. Ingenieur P Conte was reportedly inspired by the Prussian P8 design, which accounts for building this series as simple-expansion locomotives in spite of a French preference for compounding. They featured Belpaire fireboxes and prominent, outward-canted piston valves over their outside cylinders.

Wikipedia describes them as <> (pretty maids?) or perhaps "maids of all work", known as they were for their reliability and sturdiness as they were hooked up to all manner of trains -- passenger, mixed, fast freight. Depending on the grade, these engines were rated at 90-100 km/h (54-62 mph) pulling 400-500 tonnes. (This lack of fussiness probably explains the design's other nickname: La Chieuvre - The Goat).

The design's one weakness was a slipperiness on steeper grades.