W&LLR No.19

This Resita (Romania) built 0-8-0t arrived on the Welshpool and Llanfair Light Railway on 19 June 2007. Following a complete overhaul in Romania the locomotive took a 5 day trip across Europe, on a lorry, to be delivered to the railway. When built the loco was given the number 764.425 but has become No.19 in the Welshpool fleet. After a few months of running in as delivered form, as was always intended, No.19 was fitted with a Lempor exhaust ejector designed by Nigel Day and manufactured at the railway's Llanfair workshop. Unlike the other members of the W&LLR fleet there was no requirement to maintain the original chimney appearance so more freedom in the design was allowed which gives an overall edge to this ejector compared to the others fitted at the line. It has also considerably improved the appearance.

When the locomotive was purchased it was the intention that it would initially run with the Romanian exhaust system but that a Lempor would be fitted. The thought of a W&LLR loco without a Lempor was not even contemplated.

Left: W&LLR No.19 in the yard at Llanfair Caereinion prior to modification. September 2007. © N.A.H. Day

Right: W&LLR No.19 was, in Romania, No.764-425 of the TC Turda. © Shaun McMahon

W&LLR No.19 at Welshpool Raven Square prior to modification giving a clear view of the original form of chimney. September 2007. © N.A.H. Day

W&LLR No.19 in between duties at Welshpool Raven Square prior to modification. September 2007. © N.A.H. Day

The system was fitted during November 2007 following the end of the main operating season on the W&LLR. The locomotive went on to haul trains during December 2007.

A view of the Lempor nozzle, improved blower, bell mouth and mixing chamber on No.19. On the left is the vacuum ejector exhaust. As on other WLLR locos this is exhausted via the chimney, not the optimum arrangement as it interferes with gas mixing in the ejector and thus affects performance. Note that the locomotive is a saturated machine, a limiting factor on ejector performance. 17 December 2007. © N.A.H. Day

In early May 2008 No.19 was equipped with a simple box type spark arrestor in readiness for summer operations. In this view the spark arrestor, which is not currently smoothed to reduce draught loss, was being assembled. 04 May 2008

In March 2008 WLLR No.19 was tested to ascertain the ejector performance with Nigel Day leading the testing team.

W&LLR No.19 on shed at Llanfair Caereinion on the morning of testing. As can be seen the new exhaust stands somewhat taller than the original. © N.A.H. Day

W&LLR No.19 and her crew on the test day. On the right is driver Bruce and in the cab is fireman Patrick. On the balcony of the coach is W&LLR CME Colin Tickle © N.A.H. Day

Some of the test gear on show in No.19's cab. © N.A.H. Day

Unlike the other locos in the W&LLR fleet, which all have Lempor ejectors installed within the old chimney, No.19 has an unhidden Lempor ejector as is clear here showing the tapered diffuser. © N.A.H. Day

W&LLR No.19 on test near Dolarddyn © Keith Bide

The ejector performance is seen in the graph below, as can be seen it is slightly below that of SAR Class 26 No.3450 but well above that of many other ejector types on much more advanced/efficient locomotives. It might seem strange that the performance is not better but it is often overlooked that ejector performance is not just a function of the ejector design. The design and performance has to be in harmony with the rest of the locomotive. Factors such as the exhaust steam circuit, cylinder and boiler design can limit performance, factors which are in evidence with No.19. Other than the Lempor ejector the locomotive has received no other efficiency modifications.

Exhaust System Performance

In as delivered form No.19 was using, on average, 30 buckets of coal per round trip. Once the Lempor was fitted fuel consumption fell to around 20 buckets of coal. This is still higher than the other locos in the W&LLR fleet so efforts are to be made to further increase the locomotive's efficiency. A further decrease in average fuel consumption has been noted following the fitting of the spark arrestor, felt to be due to a slightly more even pull over the tube bundle which better suit the current combustion arch alignment, this being caused by the presence of the arrestor.