Puffing Billy, Wylam Dilly and Lady Mary

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Puffing Billy, Wylam Dilly and Lady Mary
Puffing Billy 1862
Puffing Billy 1862
Number: 3
Manufacturer: William Hedley & Timothy Hackworth
Year of construction (s): 1813-1815
Type : B n2, temporarily D n2
Gauge : 1,524 mm
Length: 6,788 mm
Service mass with tender: 13.32 t
Friction mass: 9.19 t
Wheel set mass : 4.6 t
Coupling wheel diameter: 970 mm
Cylinder diameter: 220 mm
Boiler overpressure: about 34.5 N / cm²
Grate area: 0.48 m²
Evaporation heating surface: 8.10 m²

Puffing Billy and Wylam Dilly were the first successful steam locomotives with adhesion drive and are the oldest surviving locomotives at all. They were in use on a mine railway in northern England from 1814/15 until the 1860s. A third locomotive of this type, called the Lady Mary , was taken out of service earlier and has not survived.

history

Drawing of the Puffing Billy with four driving axles
Wylam Dilly

Although Richard Trevithick had already proven with his first locomotive that the friction between wheels and rails was sufficient to pull a train , John Blenkinsop went a different way in 1812 and built his locomotives as rack-and-pinion locomotives . These proved to be useful, but the rack rails were cumbersome and relatively expensive.

The owner of the Wylam Colliery, Christopher Blackett , was interested in locomotives of the Blenkinsop design. He had only had new rails laid a few years earlier and the switch to gear operation seemed too expensive to him. So he turned to Richard Trevithick and, when the latter refused, to the mine director William Hedley to explore the possibilities of a locomotive that could run on the existing rails.

The rails of the pit consisted of L- or U-shaped cast iron profiles, and the wheels of the vehicles therefore did not need flanges (see also the beginnings of railroad tracks ). The track width was five feet (according to other data at 5 '½ ").

Hedley demonstrated through experiments with a hand-lever-powered test vehicle that a locomotive light enough to run on the mine rails could pull an economically viable load. A first test locomotive based on the test vehicle turned out to be a failure due to insufficient boiler output , but it was still enough to convince Blackett.

In 1813, Hedley was commissioned to build a new locomotive. He was supported by Timothy Hackworth , the foreman of the mine forge, and the mechanical engineer Jonathan Forster . The locomotive, later called Puffing Billy , proved to be successful, and in the next two years two more, largely identical locomotives followed, which were named Wylam Dilly and Lady Mary .

The locomotives were able to pull a 50-ton train in one hour over the five-mile (eight kilometers) stretch of the Tyne between the pit at Wylam and the port of Lemington (now part of Newcastle upon Tyne ), which corresponds to a speed of about 8 km / h. It is not known how fast they could drive without being burdened.

The operating weight of the machines was around nine tons; the tenders weighed about four tons. Although the locomotives were designed for this route, the rails could not withstand their weight in the long run. In order to better distribute the load, the locomotives were given two additional axles after a few years and thus became the first four-axle locomotives. However, there are no traces of this conversion to be found on the preserved Puffing Billy . The water tank rested on a fifth axle, which was articulated to the actual locomotive, a kind of single-axle tender (see illustration).

Puffing Billy and its sister locomotives were in operation in this form until "modern" rails were laid on the line around 1830. The locomotives were then converted back to two axles and were given wheels with flanges.

Wylam Dilly as a steamship drive

In 1822, as part of a riverboat strike, Wylam Dilly was mounted on one of the flat keelboats , creating a makeshift paddle steamer . It was used to tow the coal boats for a few months, and the machine had to be protected from the strikers by the military. Then Wylam Dilly was used as a locomotive.

Whereabouts

Puffing Billy at the Science Museum in London

Puffing Billy and Wylam Dilly remained in use until the early 1860s; No major changes were made to the drive and boiler during this time. Even then, Puffing Billy was the oldest surviving locomotive and therefore aroused historical interest. In 1862 the locomotive was initially loaned to the Museum of Patents in London , which later became part of the Science Museum . Tough negotiations over three years resulted in a sale to the museum for £ 200.

Wylam Dilly remained in operation for a few years, but was rarely used, since the coal transports were now largely handled on the North Eastern Railway . In 1868 the mine was closed and the locomotive was offered for scrap in an auction. Hedley's descendants bought the machine, had it restored and handed it over to the Royal Museum in Edinburgh in 1882 , where it still stands today.

There is no information about the whereabouts of the third locomotive, Lady Mary; however, it is very likely that it was retired a few years before 1860. Photographs of this locomotive do not seem to exist; those of the other two machines were only made when they were handed over to the museums.

Replicas

Two working replicas of the Puffing Billy exist; both correspond to the condition of the locomotive around 1862.

The first was created in 1906 at the suggestion of Oskar von Miller in the central workshop of the Bavarian State Railways for the German Museum in Munich, where it still stands today. The machine's wheels and bars can be moved during demonstrations. The replica made an appearance in the 1934 film Das Stahltier , which was filmed on the 100th anniversary of the first German railway .

Another replica was completed in 2006 for the North of England Open Air Museum.

technology

construction

The frame of the locomotive consisted of wooden beams to which the axles were attached without suspension.

The cylinders were arranged vertically above the rear wheels. This position was preferred at the time because there was a fear of uneven wear on the pistons and cylinder walls with horizontal cylinders. The piston rods working upwards were connected by levers and long drive rods to a crankshaft located below the boiler , which drove both axles via toothed wheels. There were further gears between the crankshaft and the axles so that the direction of rotation of the crankshaft and the wheels was the same.

The seemingly complicated linkage connecting the cylinder and connecting rod was designed in such a way that one end of the horizontal levers always remained above the center of the cylinder, making crossheads with slide rails superfluous. The feed pump was mechanically driven by one of the two levers that connected the piston rods to the drive rods.

When converting to four-axle machines, the arrangement of the gears was changed: the boiler and engine were raised, and the gear on the crankshaft now engaged a gear between the two inner axles from above. Due to the smaller distance between the axles, the intermediate gear wheels could be omitted.

Boiler and tender

Front view of the Wylam Dilly

The boiler was designed for a pressure of about 3.5 bar and consisted of wrought iron plates riveted together. The tubular boiler had not yet been invented at that time, and in the Blenkinsop locomotives a flame tube ran lengthways through the boiler, in which the furnace was located at one end, while the chimney was attached to the other. The small heating surface of this arrangement was roughly doubled by arranging the flame tube of the Puffing Billy in a U-shape (an arrangement that Trevithick had already used on his locomotives). The fire door was therefore off-center next to the chimney, which was also moved to one side, while there were no openings in the opposite side of the boiler and this could therefore have a curved shape.

This special feature of the boiler meant that the tender ran in front of the locomotive. The driver stood on a platform at the rear of the locomotive, while the stoker had his place on the tender. The locomotive was used in both directions, with the tender pulled or pushed.

Cylinder and control

Puffing Billy was the first locomotive to have the cylinders outside the boiler. Trevithick, Blenkinsop and, in 1825, Stephenson had preferred the cumbersome maintenance arrangement inside the boiler in order to prevent the steam from cooling down and thus condensing inside the cylinder. For this reason, the cylinders of the Puffing Billy were surrounded by a jacket that was connected to the inside of the kettle so that hot water could flow around the cylinders.

The control was driven by two rods arranged parallel to the piston rods on the rocker arms, which actuated rocker arms via two stops at the end of the respective cylinder stroke, which reversed the steam direction. These levers could also be adjusted manually to start or change the direction of travel. It was not possible to use the steam expansion as with later control designs based on eccentrics .

Technical specifications

The information in the table applies to the Puffing Billy in the retired state. It can be assumed that this data has changed over the course of time and that the three locomotives also differed in details, as there was no real series production around 1815. On the pictures is z. It can be seen, for example, that the kettle of the Wylam Dilly is a little longer than that of the Puffing Billy, although it is unclear whether this difference existed from the beginning or was only created during a later renovation.

Naming

Puffing Billy was probably not the locomotive's "official" name, but a nickname. It is said that William Hedley suffered from asthma , and according to an anecdote, the name of the locomotive, in German for example Schnaufender Wilhelm , came about as an allusion to the constructor's illness.

It is also unclear when the other two locomotives got their names. "Dilly" was the name the population originally called the route on which the locomotives operated.

literature

Wolfgang Kilian: 200 years of Puffing Billy . In: Eisenbahn Magazin . No. 11 , 2013, ISSN  0342-1902 , p. 40 .

Individual evidence

  1. Wolfgang Kilian: 200 years of Puffing Billy . In: Eisenbahn Magazin . No. 11 , 2013, ISSN  0342-1902 , p. 40 .
  2. Wylam Dilly and the Keelmen ( Memento of 4 July 2004 at the Internet Archive )
  3. ^ Locomotive. National Museum of Scotland, accessed May 7, 2012 : "Wylam Dilly, a railway locomotive constructed by William Hedley, 1813, used to pull coal along the Wylam Wagonway to the river, near Newcastle upon Tyne."
  4. ^ Deutsches Museum: The "Puffing Billy" by William Hedley
  5. ^ Replica of the North of England Open Air Museum
  6. ^ William Hedley: The Puffing Billy Steam Locomotive