Nord 4-6-4 Locomotives in France

Class 3.1101 Orpheline (Locobase 2751)

Data from "Baltic Type Locomotive", American Engineer, Volume 87, No. 4 (April 1913), p. 87., "4-6-4 Compound Locomotive, Northern Railway of France," The Locomotive, Volume 17 (15 July 1911), p. 155; and "New 'Baltic' Type Locomotives of the Northern Railway of France", Railway Engineer, Volume 31, No 12 (December 1910), p. 402-404.(Thanks to Alexander Blessing for his 19 November 2023 email correcting or adding data.)

Gaston Du Bousquet introduced these engines in trials as his solution to the ever-increasing power demands of express railroading. OS Nock (RWC IV, pl 153) argues that the design certainly merited better than circumstances allowed after Du Bousquet's retirement soon after they started testing. RE explained that the two were to be evaluated "taking into consideration first cost, cost of repairs and maintenance, evaporative power and fuel economy."

The two examples differed in builder and firebox, with Schneider producing the engine with a round-top boiler (Locobase 16045) and Nord's La Chapelle choosing the Belpaire firebox (described here). Trials showed the design capable of 2,800 indicated horsepower.

Like the 3.1102, the 3.1101 used different stroke lengths for the high- and low-pressure cylinders. The boiler had three sizes of tubes: 34 2 1/8" (54 mm), 97 2 3/4" (70 mm) Serve internally finned tubes, and the 27 flues holding the Schmidt superheater tubes.

Roland Arzul's account -- [], accessed 27 November 2006 - relates that the tonnage rating for this design was 400 tons at 120 km/h (74 1/2 mph). At the time of their delivery, these engines were the largest passenger locomotives in Europe.

Despite this performance, the design proved too ambitious, having appeared prematurely in response to a requirement that wouldn't truly develop until the 1930s. Only the two were built, hence the "Orphans" nickname and both were retired from service in 1924. But during their active lives, they operated on the Paris-Calais and Paris-Belgium expresses, later hauling heavy passenger trains that made frequent stops.

Class 3.1102 Orpheline (Locobase 16045)

Data from "Compound Express Locomotive, Northern Railway of France," Locomotive Magazine, Volume XVI [16] (15 October 1910), p. 223; and "New 'Baltic' Type Locomotives of the Northern Railway of France", Railway Engineer, Volume 31, No 12 (December 1910), p. 402-404. (Thanks to Alexander Blessing for his 19 November 2023 email correcting or adding engine and tender weights, boiler pressure, tube length.)

Gaston Du Bousquet introduced these engines in trials as his solution to the ever-increasing power demands of express railroading. OS Nock (RWC IV, pl 153) argues that the design certainly merited better than circumstances allowed after Du Bousquet's retirement soon after they started testing. RE explained that the two were to be evaluated "taking into consideration first cost, cost of repairs and maintenance, evaporative power and fuel economy."

The two examples differed in builder and firebox, with Schneider producing the engine with a round-top boiler (described here) and Nord's La Chapelle choosing the Belpaire firebox (Locobase 2751). Trials showed the design capable of 2,800 indicated horsepower.

Of the two designs, this was by far the more unconventional. The watertube firebox had 623 tubes making up the enormous direct heating surface area; the total comprised 287 of 30 mm (fire side)/35 mm (water side) diameter, 200 of 25 mm/35 mm and an additional 136 30 mm/35 mm tubes in the combustion chamber The boiler had three sizes of tubes: 38 2 1/8" (54 mm), 97 2 3/4" (70 mm), and the 27 flues holding the Schmidt superheater tubes. Like other water tube firebox experiments, this design didn't offer enough of an advantage to offset all the complication. The Nord installed a regular Belpaire firebox in 1913.

The careful observer will note that this is one of the few steam locomotives with different stroke lengths for the high- and low-pressure cylinders. RE's Blundstone acknowledged the long wheelbase of this design, writing "To obviate inconvenience ... [in passing] from curves to straight ...and vice versa, a very supple system of suspension has been adopted. All the coupled-wheel springs are yoked together by means of equalizing levers ...[ensuring] the invariability of the static loads per axle." (The rear bogie was equalized transversely.)"

Roland Arzul's account -- [], accessed 27 November 2006 - relates that the tonnage rating for this design was 400 tons at 120 km/h (74 1/2 mph). At the time of their delivery, these engines were the largest passenger locomotives in Europe.

Despite this performance, the design proved too ambitious, having appeared prematurely in response to a requirement that wouldn't truly develop until the 1930s. Only the two were built, hence the "Orphans" nickname and both were retired from service in 1924. But during their active lives, they operated on the Paris-Calais and Paris-Belgium expresses, later hauling heavy passenger trains that made frequent stops.

To show the innards of a typical steam locomotive, exhibitors at the 1937 Universal Exposition cut away the boiler on the 1102. Obviously no longer useful in this form, the locomotive was later shipped to the French National Railway museum at Mulhouse.

Class 3.801/Bleriot/232TA 1 (Locobase 20051)

Data from "Heavy Tank Locomotive, Northern Railway of France", Locomotive Magazine, Volume 18 (15 June 1912), p. 115 and supplement with cutaway.

These were the last locomotives to be designed by Gaston du Bousquet. Their nickname of "Bleriot" undoubtedly derived from the French flyer Louis Bleriot's fame as the first aviator to cross the English Channel (or, more properly, La Manche), which occurred on 25 July 1909.

LM's report on this class notes that these suburban tanks had to run bi-directionally, as did most suburban tanks, but they had a very useful duplication of the reversing gear, regulator (North American throttle), brake, and pressure gauges mounted on both the front and rear walls of the cab. Fitted with a Belpaire firebox and Serve internally finned tubes, these engines presented a familiar picture of French design. A Caille-Poltaire feed water heater preheated the incoming water to 90 deg C (194 F).

But LM notes the "novelty" of the compensation system, which smoothed out running at even high speeds. It began with fully compensated driving axles, with the trailing springs connected to the double beams of the rear bogie through long balance levers. (Front trucks were compensated independently.) The "excellent results" included "the movement of the engine being remarkably steady, even at high speeds."

After the first 35 were delivered with saturated boilers and slide valves, the Nord began taking delivery of locomotives with Schmidt superheaters; see Locobase 20052. Compensating for the lesser power of the saturated engines, the Nord raised the engines' boiler pressure setting to 14 kg/sq cm (13.73 bar; 200 psi) beginning in 1924.

Class 3.836/232T 361 (Locobase 20052)

Data from "Heavy Tank Locomotive, Northern Railway of France", Locomotive Magazine, Volume 18 (15 June 1912), p. 115.

Locobase 20051 describes the 1909 du Bousquet tanks delivered with saturated boilers and slide valves. These follow-on tanks had most of the same dimensions and design as the 3.801s as well as the Belpaire firebox and Serve tubes often found in French locomotives.

As usual, finding room for larger-diameter flues to hold the superheater elements meant a reduction in small tubes. The new boiler held ten smooth tubes as well as the Serve bundle. Unusually, the railroad specified larger cylinders with piston valves to "employ the superheated steam to greater advantage". The installation, LM understood, showed "a decided economy over others of similar type."

The last five of this group of 30 engines was built at the Nord's Hellemmes shops. They had more grate area.