Based on the class 229 2-6-2T tank locomotive of the Südbahn and kkStB, Ernst Prossy developed the class 629 for the Südbahn. In order to be able to increase power while maintaining the axle and meter loads, a leading bogie was used. With an unchanged driving wheel diameter of 1,614 mm (63.5 inches), they were suitable for passenger and light express trains. Approval was initially granted for 85 km/h and later increased to 90 km/h, and even 110 km/h was achieved on test runs.

After the Südbahn had received 15, Gölsdorf also adopted the design with small changes for the kkStB and had 25 more built. Larger numbers were only created after the First World War, when the BBÖ, the ČSD and the PKP had more machines built. The ČSD in particular ultimately made it to a total of 234 with its class 354.1 locomotives built by Škoda. These were characterized by two steam domes with a connecting pipe.

The class 109 of the Südbahn was created in 1910 when a more powerful successor of the class 32f 4-6-0 express locomotive was needed. The requirements included a top speed of 90 km/h, suitability for curves of 150 meters, a maximum axle load of 14.4 tonnes and enough power to haul a train weighing 320 tonnes including locomotive and tender up an 1.25 percent incline at 40 km/h. This required a grate area of around 3.5 square meters.

To achieve the needed grate area, the firebox had to be made wide, what necessitated a boiler that was high enough above the driving wheels. These had a diameter of 1,740 mm. Between 1910 and 1914, 44 were built by the StEG factory, Floridsdorf and Wiener Neustadt. Later, a variant called class 109.1 was built for Hungarian lines. Seven of this were built in 1913 by MÁVAG and two more in 1917 by Floridsdorf.

After World War I, 17 stayed in Austria and when the Südbahn was nationalized in 1923, they became BBÖ class 209. Ten had become MÁV class 302.6, which were joined by four heavier ones built between 1927 and 1930 which were designated class 302.5. 13 came to the SHS state and later Yugoslavia and became JDŽ class 03. Also 13 came to Italy and became FS class 653.

In 1938, the 17 BBÖ locomotives became Reichsbahn class 38⁴¹, joined by the 13 Yugoslavian ones in World War II. After the War, the BBÖ continued to use the class number 38. Seven were equipped with a Giesl ejector, increasing their power considerably. Depending on the country of service, they were withdrawn between 1962 and 1968. Today three are preserved, with one each operational in Austria and Hungary.

The class 32c of the Südbahn was a 0-6-0 freight locomotive and a direct successor of the 32a and 32b. Like its predecessors, it had a boiler overhanging at the front and the rear, but its Stephenson valve gear was now installed inside the frames. For use on steep lines, it had two steam domes. After only 21 of the predecessor classes had been built, a total of 73 members of the class 32c were built between 1884 and 1900. They came from the StEG factory, from Wiener Neustadt, from Floridsdorf and from MÁVAG.

Although designed as freight locomotives, they were also used for other types of trains. They could be found on the Semmering, in South Tyrol, in the Puster Valley, on the Karst and in Hungary. After World War I, only 20 remained in Austria and became BBÖ class 58. The last one of these was taken over by the Reichsbahn in 1938 and was now numbered 53 7121.

18 locomotives which had been in use in Hungary now became class 333 of the MÁV. The last one of these survived until 1966. With 29, the Italian FS was now the largest user of the 32c. Here they became gruppo 333 and most were already retired in the twenties. Of the last four, three were retired in 1932 and the last one in 1934.

After the 0-8-0 wheel arrangement had established itself with the class 33 and 34 locomotives on the Semmering, the class 35a was created in 1871. Under the direction of Louis Adolf Gölsdorf, a new locomotive was created that, unlike its predecessors, had an inside frame and outside valve gear.

Since an axle load of 13 tonnes was now permitted, a significant increase in power was possible. With a length of 2,300 mm, the firebox achieved a maximum for its time. Because it was completely behind the last axle and this had lateral play of 20 mm, there was a large overhanging mass. With a top speed of 35 km/h, however, this was of little consequence.

Production comprised 25 locomotives from Wiener Neustadt, 25 from the StEG workshops and five from Floridsdorf in 1871 and 1872. After the Upper Italian SFAI had loaned a locomotive for testing, 60 almost identical locomotives were ordered from Wiener Neustadt. These led to the later FS class 420, which was built by other manufacturers until 1905.

The locomotives of the class 35a were able to pull 210 tonnes on a ramp with a gradient of 2.5 percent. In addition to the Semmering Railway, they were also used on the Brenner Railway and in the Karst Plateau of present-day Slovenia. Like their predecessors, they were later given Kobel chimneys.

After the Second World War, 20 came to the FS and became class 452 there. 23 came to the Kingdom of the Serbs, Croats and Slovenes, of which 16 were later taken over by the JDŽ as class 132. The twelve locomotives remaining in Austria became the class 471 of the BBÖ. The three locomotives remaining in 1938 were numbered by the Reichsbahn as 55 5601 to 5603.

After the class 35a, the Südbahn had ten other very similar locomotives built by Sigl in Wiener Neustadt. Since the 35a was said to have a boiler “overflowing” with tubes, the 35c received fewer heating tubes. The tube heating area fell from 159 to 138 square meters, while the grate area remained unchanged and the area of the firebox hardly changed. In addition, they were fitted with a Le-Chatelier-Ricour countersteam brake.

After the First World War, two came to the Italian State Railways, where they became Gruppo 454. The rest all came first to the state of Serbs, Croats and Slovenes and were later classified by the JDŽ, just like their predecessors, in the class 132. Thus, the BBÖ did not receive any members of this class at all.

The Südbahn class 480 was a 0-10-0 freight locomotive that was based on the classes 180 and 80. While the former ones had been limited to a lower axle load, the 480 could utilize the network's maximum of 14.5 tonnes, allowing for a bigger boiler. Only six were built and the last three were directly delivered to the BBÖ due to the financial problems of the Südbahn.

Their main task was helper service on the Semmering. In 1938, they received the numbers 57 601 to 57 606. After the war, the ÖBB made them class 257. In 1957, three were equipped with Giesl ejectors. Three years earlier, the first one had already been retired and the last one was retired in 1966. Today, 257 601 is still existing in an non-operational state and unfortunately, 257 605 has been scrapped in 2006.

When the Südbahn made the decision to procure new express locomotives in 1881, the focus was basically on the class 16a “Rittinger” built in 1873. Since the train weights had increased from 70 to 80 tonnes before to around 150 tonnes and the use on gradients of up to 2.5 percent was required, the tractive effort had to be greater. To achieve this, the wheel diameter was reduced from 1,900 to 1,720 mm and the rear driving axle was placed under the firebox to increase the adhesive weight. Like the 16a, it had outside frames and Stephenson valve gear.

The first ten locomotives were delivered in 1882 and designated class 17a. The Košice–Bohumín Railway (KsOd) also bought ten more between 1884 and 1891. They almost exploited the axle load of 13 tonnes that was now permitted. During the official approval runs they reached 115 to 120 km/h without a load and with the weight of a regular express train they could easily maintain 80 km/h.

In 1884 and 1890, the Southern Railway procured a total of 14 of a heavier variant, which was listed as the 17b. This was followed by another 60 of a similar variant, which had a boiler pressure increased by one bar and a slightly larger boiler. They made full use of the axle load of 14 tonnes that was now permitted. Together with two other locomotives built in 1885, they became the class 17c.

In view of the increasing train weights, a locomotive had already been built in 1888 that had larger driving wheels and cylinders and a Belpaire firebox. Together with three other locomotives delivered in 1890, it was listed as class 17d.

After the collapse of the Austro-Hungarian monarchy, the remaining locomotives were distributed over the successor states. Apart from Austria, this affected the states of Hungary, Yugoslavia and Czechoslovakia. The BBÖ no longer had any of the class 17a, the rest were distributed over several classes. These were class 103 for the last two 17b, 403 for the two 17c built in 1885, 503 for the production version of the 17c and class 603 for the 17d. In Austria the class disappeared in the 1930s, in Yugoslavia only in the 1950s.

From 1903, Gölsdorf had 17 class 129 tank locomotives built, which had a 2-6-0T wheel arrangement and were intended for commuter service. In 1903, the Südbahn ordered eleven of these locomotives with larger supplies, which were given a trailing axle. The kkStB also ordered 239 of these locomotives, designated as the class 229, and rebuilt the class 129 in the same way. The Serbian State Railways and the EWA also received some machines. After the First World War, a total of 145 locomotives came to the ČSD, where some were superheated and some were given a trailing bogie. The 90 locomotives of the BBÖ were designated by the Reichsbahn as class 75⁹ from 1938.

The “Bavaria” was one of the four locomotives which took place in the Semmering competition. It was built by Maffei in Bavaria and used an all-adhesion principle. The locomotive itself rode on a leading two-axle bogie and two additional axles which were mounted in the frame with a long wheelbase. The leading one of the two axles in the frame was driven by the cylinders and the trailing axle was driven by coupling rods. To also drive the axles of the leading bogie, there were chains running from the main driving axle. Additionally, all three axles of the tender were also driven through chains and coupling rods. 

In the competition, the “Bavaria” won over the other three, maybe due to its greater adhesive weight. It was now bought by the state. However, further trial runs with heavy trains showed that the chains wore out very quickly and broke after only some days of hard work. With only two driven axles, it would have been much less powerful than the other locomotives which had lost in the competition. In the end, the Semmering railway was operated by Engerth locomotives in the first years.

After a few Engerth locomotives with two driving axles and a three-axle tender for passenger service had already been built from 1855, more were built from 1856 for use in front of freight trains. Compared to the first 0-6-4T locomotives, they were slightly lighter and had slightly lower boiler pressure, but slightly larger driving wheels. There were again 26 locomotives, which were supplied by the locomotive factory in Wiener Neustadt. The state railway first took it over as class 21 and redesignated it class 27 in 1864.

Between 1871 and 1884 they were also rebuilt into regular tender locomotives. However, they did not receive an additional driving axle, since the weight of the firebox could also be carried in this way. Until the beginning of the First World War, all examples were still in use, only in 1915 one had to be retired. After the end of the war, all remaining 25 were handed over to Italy as reparations and used there as class 197 of the FS. Their service life ended between 1925 and 1929.