A few years before the First World War, Jean-Baptiste Flamme developed a very powerful boiler that was to be installed in a freight locomotive and an express locomotive at the same time. So from 1909 the type 36 with the 2-10-0 wheel arrangement and from 1910 the type 10 Pacific were built. Since the boiler was relatively short with a large diameter and the chassis of the Pacific naturally had a long overall wheelbase, the appearance of the Locomotive somewhat unusual with a long overhang in front of the smoke box.

The boiler had a grate area of five square meters and narrowed in front of the firebox. It delivered 2,250 hp, making the type 10 one of the most powerful Pacific locomotives in Europe. Since the bogie hardly had to carry any weight from the smoke box, the load was kept within limits despite the four cylinders with simple steam expansion. Due to the special arrangement of the cylinders, the inner cylinders were accessible from above, which made maintenance easier. Although the cylinders were in one plane, the inner ones drove the first driving axle and the outer ones the second. The problem, however, was the weight of the large firebox, which made the load of the trailing axle too high. The Type 36 didn't have this problem as the weight was carried by the coupled axles. 

As a result, the second batch from 1912 was delivered with a smaller grate surface in order to reduce the axle load on the trailing axle. However, this reduced the power to 1,950 hp, while the service weight of the locomotives was reduced by around four tons. A total of 58 pieces were made by 1914, when production was stopped due to the war.

Locomotive Magazine, July 1910

In the 1920s, the locomotives received double chimneys and new feed pumps. From 1931 there was a major conversion with new feedwater heaters, a larger superheater, new safety valves and smoke deflectors. The result was an output of 2,700 hp for the first batch and 2,400 hp for the second batch. 1938 followed the installation of Kylchap blast pipes. A large proportion of the engines were retired in 1956 and some continued to run on a different route for three more years.

In 1939, the Belgian State Railways ordered Cockerill to build six streamlined Atlantics to speed up express trains between Brussels and Ostend. While this wheel arrangement was already unusual at the time, the inside cylinders with outside valve gear were also unusual. With a maximum permitted speed of 140 km/h, trial runs reached 165 km/h, while the trains often exceeded an average of more than 110 km/h. Average speeds of 120.46 km/h from station to station were also achieved, which is still the European record for steam trains to this day. When the route for which the locomotives were built was electrified, they were used on other routes. They were decommissioned by 1962 and road number 12 004 is now in the “Train World” in Schaerbeek.

A few years before the First World War, Jean-Baptiste Flamme developed a very powerful boiler that was to be installed in a goods and an express locomotive at the same time. From 1909 the type 36 with 2-10-0 wheel arrangement and from 1910 the Pacific of the Type 10 came into existence. The boilers differed only in the firebox, which had enough space between the last coupled axle and the trailing axle on the type 10, but had to be accommodated above the last two coupled axles on the type 36.

The very large firebox had a direct heating surface of 19 square meters and included a grate of 5.1 square meters. The long boiler tapered in front of the firebox, but still had a large diameter in the front area. It made the Type 36 the most powerful goods locomotive in Europe.

To ensure running in curves, the leading axle was combined with the first coupled axle to form a Zara steering frame, and the last coupled axle could be moved 29 mm to the side. The four cylinders were all in one plane and were only controlled by two external Heusinger valve gears for easier maintenance. The inner cylinders acted on the second coupled axle, and the outer ones on the third.

In a first series, 136 pieces were completed, 17 more followed after the First World War. 113 of the pre-war machines were rescued to France during the war, where they were not used due to their high axle loads. As early as 1915, 60 units were sold to Russia, where they were to be used on standard-gauge routes in Eastern Europe. Ultimately, they were converted to broad gauge and used in the Soviet Union until 1962.

The engines returned to Belgium were fitted with double blast pipes and longer smokeboxes in the 1920s. Together with other smaller conversions that were made up to the early forties, the service weight increased by almost four tons and the power to 2,300 hp. They were now designated type 36^bis and were used until 1947.

After the standard gauge rebuilt

Locomotive Magazine, April 1893

The Antwerp-Ghent Railway ordered these two locomotives with the intention of later converting them to standard gauge. So they were built by the manufacturer in such a way that the wheels with a gauge of 3 ft 7 in can be removed inside the frame and reinstalled outside the frame with a gauge of 4 ft 8 1/2 in. This plan was implemented in 1899, at the same time the cab was closed and the Westinghouse air brake was retrofitted.

In order to be able to burn cheap coal with the smallest fragments, the Belgian State Railways needed a large firebox for their express locomotives. This also applied to the type 12bis, which was based on the type 12 from 1888 and where the “bis” stood for “second”. In order to achieve the required power, the grate area had to be further increased to 4.7 square meters or 50 square feet. 

On the 12bis, too, the firebox consisted of a narrow, front part between the wheels of the second driving axle and a wide, rear part above the trailing axle. It still had outside frames, as well as serve tubes and a conical chimney. It was said to run smoothly even at 110 km/h (68 mph). 

In 1932, the Belgian firm of Ateliers Métallurgiques in Tubize built the world's only Quadruplex locomotive with the assistance of the Italian Attilo Franco. Its special design was not only to increase power, but also to increase efficiency. It was much larger than anything the Belgian Railways needed, but was used as a prototype for a planned compound hexaplex locomotive for the Soviet Railways that was even larger, but never realized.

The locomotive consisted of three sections called A, B and C. The middle B section housed a special double boiler that had two central fireboxes. These were located side by side, were each fired by one fireman and had their own coal bunker. Each end of this section had a cab since the locomotive was way too long to use turntables.

Locomotive Magazine, August 1933

The A and C sections contained large Franco feedwater heaters which were encased by the water tanks. The chimneys were on the extreme ends of these sections since the hot gases only escaped to the atmosphere after passing through the feedwater heater. A part of the hot gases was ducted to the grates to mix with the cold air.

A total of ten driving axles were powered by four pairs of two cylinders each. The B section had two pairs of two driving axles, with carrying axles at the ends and one in the middle. The A and C sections had three driving axles and one trailing axle. This led to the wheel arrangement 0-6-2+2-4-2-4-2+2-6-0T. With this arrangement, the locomotive could pull 1,200 tonnes on an incline of 1.6 percent. Additionally, it was found to have a low specific consumption.

After the trials, the locomotive with the builder's number 2096 was shown on the Brussels exhibition in 1935 and then withdrawn. In 1943, it was split in half and rebuilt to two 0-6-2+2-6-2T locomotives by adding an additional driving axle below the half of the old B section. After getting to Germany in 1944, they were used in a shipyard. When the war ended, the Soviets brought them to two different locations in Poland where they were used for a few years.