Sunday, 15 November 2015

STAINMORE MINERAL WAGONS - By Phil Baines



 
© ForgottenRelics
  IN ORDER to understand the rolling stock used by the Stainmore railway it helps to know a little of the origins of the route.
  The Industrial revolution was powered by steam, fuelled  by coal and built of iron.  The need to supply these heavy minerals to the burgeoning industrial areas could not be met by the roads and transport available at the time, hence the investment in railways, ideal for bulky heavy traffic, to fulfil the need.
  Initial growth in iron production was adjacent to the ore supplies and saw the development of large iron making complexes in both the North East of England and West Cumberland. The need to transfer minerals across country to feed these industrial complexes was instrumental in the demand for a Trans-Pennine railway, but was further enhanced by a quirk of geology.
  The iron ores quarried/mined in West Cumberland were much lower in phosphorus content than those of Durham/North Yorkshire, which has a significant impact on the quality of steel that is produced.
  In 1856 the production of steel was vastly enhanced by the development of the Bessemer Furnace, the first of which was installed in Workington and this, combined with the quality of the iron ore, meant the Cumberland Ironmasters had a huge demand for coal and coke to fuel their furnaces.
  Consequently, it was a win win situation with coal and coke shipping East to West and quality iron ore West to East, a route over the Pennines was inevitable. Construction started in 1857 and the line opened for mineral traffic in 1861.
  The NER was the principle operating company associated with the mineral traffic over Stainmore and were to develop a number of suitable  wagons over the years, but the final format was the P7, which were produced in huge quantities (by the time of the 1923 grouping there were over 17,000 of the NER wagons in use).
   Construction started in 1903 and, as was often the case, the design evolved over time. The above picture is typical of the early construction with brake levers at both ends but brake pads only to one side. Note the extended end posts which acted as dumb buffers when the wagons were shunted with Chaldron wagons.
  The NER undertook a number of experiments with these vehicles to attempt to reduce rolling resistance including the provision of a second outside set of W irons  to add stiffening to the axles.  A further variant, saw an anti-friction bearing added.  This was a wheel that ran on the top of the axle and the idea was that as it rotated less, there would be less friction.  The introduction of an open bearing surface that would instantly get contaminated with coal and dust would actually have the exact opposite impact  and these were no longer seen by the grouping era.
  Following grouping many of these wagons passed into LNER hands,  who quickly decided to chop off the extensions and this version is the first mineral wagon created for the route.
  The other major variation to the P7 was the provision of brake handles to the side, rather than the end and this is the second variant modelled for the route.


  The LNER were obviously happy with this design as they went on to produce over 7000 wagons to an almost identical pattern, the principle difference being the use of T-section iron end posts in place  of the wooden ones seen in the NER versions. These wagons were to continue in service for a long time, some were still in use in the 1960's, many finding work as internal user wagons in NCB coal yards long after retirement from main line use.
  This was the third variant modelled for the route, shown here in Workington Iron & Steel Co. livery. Note that, as can be glimpsed in this picture, all these wagon models can be selected as either unloaded or with a coal load.
  It is of interest to note that the NER discouraged the use of Private Owner wagons, preferring to lease out its own high capacity hopper wagons at competitive rates, in the interests of standardisation,  rather than allowing PO versions, However, any that can be identified may be included with the route.
  The final variant is a low poly version of the LNER wagon for populating sidings.
  The Railway Clearing House (RCH) was an organisation supported by all Britain's railway companies. Its main function was to apportion income for journeys that crossed company boundaries, but it also had the role of developing standard patterns for wagons, which could be built by any railway company or private owner in the knowledge that they would be accepted anywhere.
  In 1907 the Railway Clearing House (RCH) prepared a set of regulations for the construction of 8,10 & 12 ton wagons, however after about 1910 the 12 ton wagons became more popular and by 1923 a new RCH specification was released, a rugged and simple design employing standard RCH fittings throughout, which included oil axleboxes, brake shoe that could be fitted universally and coil sprung buffers. Originally they had to be built with seven side planks, making an overall body height of 4' 4", although an 8 plank variant was later permitted, plus various configurations of side doors, end door and bottom doors, however, the weight of the unladen wagon was not to be above 7 tons 5 cwt. It became the most numerous design of coal wagon built in the UK.
  The 1923 RCH standard was used not only for private owner  wagon construction, but also readily adopted by the L.M.S. and L.N.E.R. In fact the L.M.S. constructed more that 30,000 wagons to the standard 7-plank design many wagons lasting well into the 1960’s.
  Whilst typically used to transport coal for domestic and boiler use rather than steelworks, they undoubtedly played a significant part in the Stainmore mineral traffic.
  An LNER version has been modelled for the route, other liveries may be included, along with low poly versions.
  Because coal has a density, when in lumps, of  about 1100kg/cu metre, compared to 550-65kg/cu metre for coke, the carrying ability of these wagons was under resourced when used for coke, therefore, there was a need to enhance the volumetric capacity. This was achieved by raising the overall height of the wagon with additional planks known as "raves". An example of this is included with the route.
  In view of the extensive use of hopper wagons for the conveyance of coal, in 1936 the LNER released diag 100, a design for an all steel riveted construction 20 ton hopper wagon. They would later be upgraded to 21 ton capacity.
This was to be nearly as successful as its NER predecessor with over 13,000 built prior to Nationalisation. Following nationalisation the 21ton steel-bodied coal hopper was the standard BR coal hopper until the advent of air-braked types in the 1960s and 1970s. The first three lots built for BR comprised a total of 1200 wagons to diagram 1/141, built in 1949 the design was identical to the LNER-built wagons and even featured the distinctive straight brake levers. Over 23,000 wagons were built, making them one of the most numerous types on BR. The LNER version has been modeled for the route.
  In many pictures these wagons have plates riveted to the side of the hopper body, but, as they aren't shown in Peter Taplow's famous book, nor did they appear consistent with the construction of the wagon, they were omitted from the model. Examples of the plates can be seen in this welded version hopper at the NYMR.
  I have since established that these are "Rap" plates. They were strong points on the hopper so it could be hit (rapped) with a sledge hammer to dislodge wet or frozen coal that had become stuck in the wagon! Never too old to learn. . . . . . . . . . . . . .

1 comment:

  1. Damp coal sticks very easily in chutes and blockages aren't uncommon. When I was a newly-graduated engineer, back in the seventies, I worked for a company that built large industrial boilers and worked on our products at power-stations amongst other sites. Coal-fired systems would have vibrators fitted to the side of chutes to try and keep things moving but I did hear of various ad-hoc arrangements to clout a hopper and dislodge stubborn material. I can well imagine the need for rapping plates on these wagons.

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