Dinorwic and George
| Dinorwic and George | |
|---|---|
_works_photo.jpg) Hunslet factory recording of the Dinorwic
|
|
| Number: | 2 |
| Manufacturer: | Hunslet |
| Year of construction (s): | 1870, 1877 |
| Type : | B n2t |
| Gauge : | 578 mm |
| Total wheelbase: | 1295 mm |
| Service mass: | 9.1 t |
| Friction mass: | 9.1 t |
| Driving wheel diameter: | 610 mm |
| Cylinder diameter: | 191 mm |
| Piston stroke: | 356 mm |
| Boiler overpressure: | 103.4 N / cm² |
| Evaporation heating surface: | 14.86 m² |
| Water supply: | 0.9 m³ |
The Dinorwic and George locomotives were narrow-gauge tank locomotives for use in the Dinorwic quarry in North Wales . They are believed to be the first Quarry Hunslets , and their design principles have remained essentially unchanged for decades.
history
The Dinorwic , built by Hunslet in 1870 , was not only the first of the locomotives that railway enthusiasts today call Quarry Hunslets, but also the first narrow-gauge locomotive built by Hunslet with the number 51.
The locomotive was used on the connecting line between the workshops called Mills , in which the slate was processed, and the reloading station for the Padarn Railway , the connecting line to the port. Up to twelve horses had been necessary for this task. In 1877 a second locomotive was added, called George (factory number 184).
How far the George was identical to the Dinorwic is not certain. The factory photo and the overview drawings have not been preserved, and otherwise there is probably only a presumed picture of the locomotive, which could also show the Dinorwic . What is certain, however, is that the drive wheel and engine dimensions were the same, which makes major deviations in design unlikely due to the similar design of all Quarry Hunslets.
When a new locomotive was procured for the 4 foot (1219 mm) gauge Padarn Railway in 1882, it was named Dinorwic and the little locomotive was renamed Charlie . Like George and Louisa , this was the name of one of the children of the owner of the quarry.
The Mills Class machines delivered in 1895 and 1898 replaced Charlie and George on the Mills Tramroad, and the two locomotives were then used in the quarry's galleries. They probably continued to serve as replacement locomotives for the Mills Class.
By 1912 at the latest, George was named a racehorse with Minstrel Park , as did many of the Alice Class locomotives .
Charlie was retired in 1916 and put up for sale in 1919. However, this did not come about and the machine was still in a shed on the quarry in 1935. A year later the locomotive was scrapped.
Minstrel Park was sold to a mining company in 1919. The machine was scrapped around 1942.
construction
The locomotives were built on an external plate frame. The two coupling axles, which were only 1295 mm apart when negotiating tight curves, were driven by external cylinders via cranks. The cross heads were guided in double slideways.
The four leaf springs were arranged above the frame and the circumference. The internal control of the Stephenson type moved flat slide valves arranged within the frame. The reversal was carried out using a lever on the right-hand side of the vehicle.
The long boiler had a smaller diameter than the smoke chamber and standing boiler . The latter was located directly behind the second coupling axle and thus compensated for the front overhang of the cylinders. There was no steam dome ; the steam was taken from the slightly raised standing boiler on which the safety valves were also located.
The water tank was designed as a saddle tank and covered the entire long boiler. In contrast to the side tanks, this design ensured better accessibility of the components arranged within the frame. The driver's cab was open; Braking was carried out using a vertical hand crank.
It is noteworthy that Hunslet did not change this construction principle significantly for several decades; the construction of the last Quarry Hunslets ( Dinorwic Port Class ) built in 1922 and 1932 is basically the same. Only the horizontally arranged cylinders and the low circulation, which made wheel protection boxes necessary, were no longer repeated. The horizontal cylinders had the disadvantage compared to the inclined and thus slightly higher arranged cylinders that they were more prone to damage from rocks lying around.
literature
- Cliff Thomas, Quarry Hunslets of North Wales, Oakwood Press, 2004, ISBN 0-85361-575-6