Railway Freight Operations - Metals Traffic
Britain's wealth was built on mining. Minerals and the goods
made with them have been traded from these islands since the bronze age and it
was in large part the mineral wealth that attracted the attention of the Roman
Empire. In the 1840's just as the railways were starting to have an impact
Britain was producing seventy five percent of the worlds copper, sixty percent
of the worlds tin and over fifty percent of the worlds lead. Copper was mined
in Anglesey, Devon Cornwall and Ireland, tin was mined in Devon and Cornwall
whilst lead was mined in the Peak District (on the border of Yorkshire and
Derbyshire), in Wales, Ireland and the Isle of Man.
In addition Britain trained many of the worlds mining engineers who, not surprisingly, tended to order British equipment they knew and understood, greatly benefiting our engineering firms.
By the time the railways came along iron ore was the most important mineral being mined in the country both in terms of quantity and value. British iron ore deposits are mainly found in the North of the country, which coupled with the similar dispersion of coal reinforced the trend for heavier industries to develop in those regions. In the period between the two world wars the iron and steel industries migrated to Lincolnshire and Northamptonshire where large new steelworks were erected. British ores tend to be of indifferent quality however, so there has always been a significant import of higher quality ores from abroad.
Iron ore was a major traffic on the railways, usually shipped as block trains. In the areas where the ore was mined or quarried a block train of iron ore was probably a more common sight than a block train of coal (see map below). Hopper wagons were the usual transport and most were quite small due to the weight of the ore. Having said which the LNER pressed some of its high sided wooden coal hoppers into service for ore and British Railways continued this practice.
In Britain iron ore mining is mainly associated with Northamptonshire, Leicestershire, Rutland and Lincolnshire. These areas were covered by the LNER & LMS, and the latter had the biggest fleet of ore hoppers in the country. A fair model of the LMS type (introduced in the mid 1930's) can be produced using the N Gauge Society 'ironstone hopper' kit. There were many private owner wagons, usually steel bodied four wheel hoppers of twenty to twenty five ton capacity, these were employed on 'circuit working' between the mine or quarry and the smelting works.
For additional information on iron ore mining and the associated iron and steel works see Volume 2.
Most British ore is yellow in colour (burnt ochre pigment is actually powdered iron ore, handy for modelling the stuff). Hematite ore is red in colour, a high quality ore but not very common in Britain (see map).
Fig___ Iron Ore Deposits in the UK
In 1971 British Steel (now Corus) invested in a fleet of purpose built bogie tippler wagons for handling imported iron ore. They were used to supply various steel works, including Scunthorpe and Tees-Side. Coded PTA under TOPS these were air braked and fitted with a special rotating coupling so they could be turned upside down without detaching the wagon from the rake. In 1976 another batch was purchased and these operated what amounted to a merry-go-round service between Hunterston and the Ravenscraig steel works. Some of the Tees-side wagons were re-vamped by Procor and leased to Foster Yeoman for aggregates traffic in the early 1980s. I believe that, following the closure of Ravenscraig in 1992, the remainder found further employment but I am not sure of the details. They were thirty eight feet ten inches over headstocks and their sides were seven feet high. The imported ore was 'pelletised', basically it was reduced to marble size rust coloured pellets.
A sketch of the BSC tippler has been included in the section on Goods Rolling Stock Design - Air Braked PO stock.
Raw materials for an iron and steel works
The iron & steel industry has long been a user of the railways, both for the raw materials to the furnaces and shifting part finished materials and finished products. Raw materials included iron ore, limestone, coal and coke whilst the railways also moved ingots of pig iron from the smelting works to the foundries. The industrial side of all this is discussed in the section on Lineside Industries.
Iron ore was generally shifted in hopper wagons and in some areas coal and coke were also delivered in hoppers, all of these when feeding an iron or steel works would form block trains. Limestone was more usually delivered in short rakes of five plank open wagons and the ingots of pig iron were shifted in three or five plank open wagons.
Pig iron was supplied to foundries where it was used to make iron castings. A small foundry suitable for a model railway layout is described in the section on Lineside Industries. Given a size for the pigs of three foot by four inches by three inches (1m x 100mm x 75mm), which works out at about 123 lbs (56 Kg) or twenty pigs to the ton, a ten or twelve ton wagon would carry about 200 of these bars of iron. From photographs I would suggest having a layer about 1 or 2mm high with a few extra bars added in the middle, however wagons were not always fully loaded a consignment might be just a few tons. In 'British N' 6mm lengths of 30x20 thou strip would be about right, with one end carved about to represent the point where the 'pig' joined the main sprue. They were dark reddish brown to black in colour with occasional streaks of lighter red where fresh rust had formed.
The pigs were not stacked neatly as a rule as it didn't matter if they were damaged, prior to the introduction of specialised wagons they would be loaded carefully however as they could damage the wagon floor.
Purpose-built pig iron wagons were usually low-sided, British Railways built several designs all of which were metal bodied but the sides were about eighteen inches to two feet high. Some five plank wagons were specifically built or modified for pig iron traffic with metal girders replacing the bottom two end planks to prevent the 'pigs' from punching through during rough shunting. Peco have now introduced a BR type 20 ton pig iron wagon on a nine foot wheelbase chassis however ths definately looks better 'full' as the floor is raised to accomodate the weight. You can fit the upper floor plate directly to the chassis and add the sides for an empty wagon but you then need to glue some crushed air gun pellets to the under side as ballast. There were a number of designes inroduced by BR specifically for pig iron the 30 ton variant with the extra thick chassis can be produced from a Peco or Farish chassis as shown in the sketch.
Sheet Metal and Plates
Sheet metal is less than 3 cm thick, anything thicker than that is classed as 'plate'. Plate was carried on bogie and four wheeled flat wagons, usually with low raised sides. The main flows were from the steel works to the ship yards and larger engineering firms such as boiler makers. This means consignments ranging from a complete block train down to a single wagon load would have been seen prior to the 1970's. With the reduction in heavy engineering in the 1970's smaller consignments became much less frequent but block loads for export increased.
Larger plates (wider and eight feet) were carried on 'trestle wagons', supported at an angle on a hefty wooden trestle mounted on a wagon and secured with chains. Using a wagon with a drop centre section allowed these plates to be quite large. These wagons are discussed in more detail in the section on Goods Rolling Stock Design - Specialised Rolling Stock.
Finished steel, girders, pipes and the like are transported open vehicles, often bogie bolster wagons. The quantity being moved could be a single wagon load (perhaps two small girders for a bridge) or an entire train-load (pipes for new gas pipelines were shipped by the train load). One thing to beware of is not to over-load the wagon, see the section on Cargo & Wagon Loads for details of typical loads of this type.
Billets and slabs
A large proportion of the steel from the steel works is shipped in long rectangular sections called blooms billets and slabs, these are all discussed in the section on Cargo and Wagon Loads. This kind of traffic would be going to a major works, so block loads or comparatively large cuts of wagons would be involved.
Prior to the 1970's most of this traffic was carried on unfitted wagons. From the early 1970's finished steel, long billets of steel and coiled strip, were routinely shifted on rakes of vacuum fitted bogie stock as block workings, mainly to the docks for export.
Coiled wire was used for making nails in the Big Four era but of the pre British Railways companies only the LMS had special wagons for wire coil traffic and these are tricky to model. Most coils of wire were shipped in 5 plank open wagons in the early days of BR. In the early 1960's there were a number of conversions based on the standard BR plate wagon (as available from Peco) and one of these, the Coil E (TOPS coded KEV), represents one of the simplest possible conversions. Just add four T section strips to each end and add an L section across the top of the centre two using two lengths of 10x20 thou strip.
Fig___ Coil E wagon (modifications to Peco plate)
The SKA air braked wagon was designed for coil traffic and has metal beams forming two longitudinal cradles, the coils of wire are loaded in two rows of eight. Wire coils were also regularly shipped in SPA drop-side and SRV four wheeler wagons and the bogie BPA stock. Coils are these days sheeted during transit and this may have always been the case. Photographs are usually taken at the loading or unloading points, where the sheets had been removed.
One traffic that has become more common since the 1960's is coils of steel sheet (called `stripcoil' and used for pipe making, among other things). British Railways modified various metal bodied wagons for this work by cutting down the body and adding wooden beams to the floor to support the coils. Most of these wagons ended up looking like a low sided wagon. A model of one of the early strip coil wagons, complete with a coil load, is available from Parkwood Models.
A lot of the internally shipped coils are raw steel going to be galvanised (coated with Zinc to prevent rust) at a separate plant, the coils had to be protected from rain and the wagons used were fitted with fixed folding tent shaped hoods that would normally have remained in the closed position except when loading or unloading. These hoods proved unreliable so by the later 1970's a simple dark blue tarpaulin was the normal covering used.
As with the slabs and billets these loads would normally consist of a minimum of four or five wagons and could form a complete block load.
By the 1980's bogie flat wagons and air-braked OCA wagons were being used for strip coil.
Fig___ Strip coils and air braked wagons
By the 1980's the Lackenby plant was the only one producing stripcoil.
A map showing where these various materials were produced might be of assistance. This map dates from the 1980's, it should be noted that there were smaller works producing all these materials in various parts of the country prior to the formation of British Steel.
Fig___ BSC plants and associated products
Scrap metal has been an occasional cargo since the earliest days of the railways. The railway companies themselves had a lot of scrap rails and other materials which they sold to scrap metal dealers for re-processing. Prior to the Second World War most scrap metal was dealt with locally but during the war it was channelled into war production, laying the foundation of a national network for scrap processing.
If you favour removable loads and have a rail served scrap dealers yard on your layout the traffic flow would be mainly empty wagons in and loaded wagons out. Scrap merchants would not receive much scrap by rail, the main rail shipments would be going to a steelworks for reprocessing. Having said which they did receive a lot of waste material from engineering works, including (depending on the nature of the works) three plank wagon loads of rivet hole punchings, swarf from machine tools and hammerscale from a forge. This sort of material was quite often sent from the works by rail, much of it going direct to steel works but a proportion to scrap metal merchants (modelling these cargo types is discussed in the section on Lineside Industries - Scrap metal Yards, Foundries and Forges)
For many years the BR standard 16 and 21 ton mineral wagons were regularly used for scrap metal, as BR moved toward eliminating unfitted wagons scrap, a low value cargo, was one of the few traffics that used the older wagons. The BR standard twenty one ton mineral wagon proved its worth and the re-bodied versions with only a singe door on each side were regularly used for scrap traffic.
Fig___ Twelve foot wheelbase rebodied wagon
Although a low value cargo scrap the traffic in scrap metal did return a profit but BR were unwilling to invest in new rolling stock for the trade. Scrap metal traffic suffered a downturn in the 1970's and early 1980's, partly due to the steady withdrawal of the older vacuum braked wagon services. This in turn prompted wagon leasing companies to offer air braked scrap metal carrying wagons for purchase or hire to run in Speedlink services. Standard Railway Wagon Co (a wagon leasing company, later part of Procor) were the first to do so, building a fleet of POA four wheeler opens in 1978 for leasing by its Railease subsidiary.
Ralph Snelling made a kit available to members of the N Gauge Society of the original design of Railease POA scrap wagons loaded with scrap. This was scaled to fit the Peco fifteen foot wheelbase chassis (actually about 4mm short and with the wrong kind of suspension). These early wagons are not difficult to scratch build, if you can live with the Peco chassis. Later batches had a horizontal bar with an angled top running along the middle of the sides, this later type is much more difficult to model. The POA bodies were replaced in about 1988 with new and heavier design incorporating the horizontal bar along the centre of the sides. One or two such wagons might be included in a general goods rake, although if your layout is end-to-end you would need a scrap yard to justify them. Note my model is in incorrect livery (see below).
Fig___ POA scrap metal wagon model
The early publicity photographs showed the POA wagon body in all over yellow livery with RAILEASE in black and a black TOPS panel with white markings. The chassis was painted black. Within a year or so they had light blue solebars and sides with the top rail on the sides and all the ends painted yellow. The blue seemed to vary in service, this could have been dirt, I would suggest starting with Humbrol Cambridge (light) blue and giving this a couple of washes with well thinned black and grime. The TOPS data was painted on the side in white with white line framing but without the black background. By the mid 1980's they often had SR on the upper centre of the sides (standing for Standard Railfreight, the name that replaced Railease in about 1983) in white letters about a foot high. The later body designs had reinforced corners and on these the yellow of the ends was carried round onto this corner plate.
Later wagons, built on the chassis of redundant HAA merry go round wagons and coded PNA, all of these had the horizontal central side bar from new. Modelling these is less easy, the Minitrix HAA chassis is expensive and hard to find these days, one option is to use a Peco fifteen foot wheelbase chassis and insert a 4mm section in the centre. The wheelbase of the resulting wagons is 4mm too short but the body is about right. Bernard Taylor offers a kit of the PNA/SSA wagons, presumably designed to fit the Taylor-Farish air braked chassis.
Fig ____ POA Scrap Steel Wagon, prototype and re-bodied variants
Little interest was shown until 1984 when a new service for scrap was set up by British Rail (the railway operators), Standard Railfreight (the organisers and owners of the wagons) and United Engineering Steels of Sheffield (the customer). In this service Standard Railfreight arranged the collection of scrap which was loaded into its fleet of nearly two hundred purpose built 50 ton four wheeler POA/PNA box-body scrap wagons. These were then hauled in standard British Rail Speedlink services to the UES plants at Aldwark in Rotherham and Stocksbridge to the north west of Sheffield.
The Railease initiative worked well and BR built some similar wagons for this traffic using redundant chassis, coding these SSA. In 1990 the entire Railease fleet of nearly 200 air braked scrap wagons (of various designs) was sold to British Rail, they were then re-coded SSA and operated with the BR SSA fleet. I believe all the original POA wagons had been rebuilt with heavier side framing by the time they passed to EWS who still (2003) operate them but in their own red and yellow livery.
All of these scrap wagons were built as single purpose vehicles, specifically for carrying scrap metal. The layout of most steelworks does not easily allow the use of multi-purpose wagons, but in the early 1980's Sheerness Steel purchased some purpose built bogie wagons designed to serve for both scrap metal and finished products. These large wagons have a gross loaded weight of 102 tons but carry a payload of about 70 tons. I think the large bogie wagons were light grey with black lettering, but I cannot find the only picture I have of the type so I cannot confirm that. The sketch below was made with a view to modelling these types, something I never got round to so I did not confirm the livery details.
Fig ____ Procor bogie scrap steel wagon
(I believe the Sheerness works closed in 2002, part of the collapse of Allied Steel and Wire)
The value of scrap metal traffic may be judged by British Railways decision to convert a number of HBA hoppers to carry shredded scrap metal in the late 1980's (they were re-coded HSA following conversion). I am not sure of the details of the conversion but from memory the wagons did not differ significantly from the HBA. I do not know how long these wagons remained in service or the details of the traffic they were used for. Presumably the shredding was done in larger scrap yards for sale to reprocessing works.
The end of the Speedlink network operation in 1991 ended all these services but the re-emergence of wagon-load traffic under the Enterprise banner in 1993 brought a limited return to rail.
Lead, Copper, Zinc, Tin and Tinplate
Lead, copper, zinc and tin were all refined very close to the mines that produced them. The resulting material (ingots or rolls of lead sheet) was shipped either in sheeted wagons or covered vans. Lead, being valuable and easily sold, was usually shipped in vans. This traffic would be shipped in mixed wagon load trains.
Tin plate (shiny sheet metal, as used for food cans and biscuit tins) is steel coated in tin. Britain was a major tin exporting country until fairly recently and ingots of tin from the Cornish mines were shipped across the Bristol channel by sea to the tinplate works in South Wales. In the pre-nationalisation era the plated metal sheets were shipped in vans, including a number of private owner vans (discussed under Freight Operations - PO Stock). Customers included the tin can factories and the major cities where toy making firms and the like made extensive use of tinplate as it could be easily decorated with transfers or paint. Tinplate was shipped as wagon load traffic but for a major customer such as Metal Box (the tin can makers) a block working might be required.
Tin was also used to coat copper wire so that, when wrapped in rubber sheathing, it would not corrode, it also makes the wire easier to solder and model railway layout wire is often referred to as 'tinned copper wire'.