A Walk through Time
The images below were taken on the site throughout its history. They show the workers and the factory from many points in time. A brief description of each picture can be found below the image.
This image shows the ironworks circa 1910. In the foreground are the company offices. Behind these can be seen the furnaces and heating stoves. This picture was taken as the ironworks entered its last phase of operation, with only five furnaces remaining by this time out of eight that had at one time been in blast.
THE FURNACE WORKERS
This photograph shows a furnace crew and was taken in 1850. The furnace men were responsible for the production of the iron. The boys pictured at the front had the job of making the ‘pig beds’ which the molten iron was poured into. The pig beds were so named as they were said to resemble a sow lying on her side suckling her piglets! There were eight furnaces at Dunaskin, each with a crew this size.
This photograph was taken in 1903 and shows the iron furnaces. Railway lines can be seen leading up to each furnace. These carried out the pig iron and transported it to Ayr harbour where it was shipped to the markets.The trains along the top are carrying the raw ingredients for iron making, mainly iron ore, coal and limestone. To the right of the furnaces can be seen the heating stoves which heated the blast of air needed to smelt iron in the furnace.
The heat for the blast was provided from the furnaces, thus making the process much more efficient as waste heat was being reused. The furnaces were demolished when the brickworks took over. For an explanation of how the iron furnaces worked click on the photograph.
THE BOILER MAKERS
This picture shows a group of boiler makers. The steam boilers were used to power the blast engines and were housed in two boiler houses adjacent to the Blowing Engine House. The boiler houses were demolished to make way for kilns during the brickworks phase. This photograph was taken in 1909.
PIPERS AT ARDOON
This picture shows a pipeband playing in the grounds of Ardoon House. It is not known who the band are, although their dress suggests a military unit. This picture was taken some time in the 1940’s.
Cart horses were frequently used to carry raw materials and equipment around the site. Horses proved to be a cheaper, if slower, alternative to trains and could reach areas of the site where the railway tracks did not go. This picture was taken around 1860.
These two pictures were taken in 1921 just prior to the ironworks closing. The men pictured would not have been furnace workers, but more likely engineers, blacksmiths or performing another task important to the general maintenance of the ironworks.
THE POWER STATION TURBINE
This picture was taken in 1954 and shows one of the turbines that drove the power station. The power station was built in 1917, initially to supply power to the gunnery station located 16km south of the site, and then to all of the Doon Valley, running until 1956 when the extensions of the National Grid made it redundant. The power station ran on waste coal which was burned to provide the power to run the turbines.
The man in this picture is a joiner for the Dalmellington Iron Company, identified as ‘Duck Shaw’. The photograph was taken sometime between 1900 and 1915.
How the Furnaces Worked
The iron furnaces were where the raw materials were ‘cooked’ to produce the pig iron. There were initially five furnaces at the beginning of the iron working period, which had expanded to eight in 1870. These were replaced after 1871 by larger capacity furnaces which were capped to trap the waste gases which were then extracted and used to produce secondary by-products, for example coal gas, tar and pitch.
The diagram below illustrates the design and temperatures experienced in an iron furnace. The design is identical to that of the furnaces used at Dunaskin. The furnace was made of large refractory bricks, which could survive the high temperatures attained inside the furnace. The furnace towers stood over 20 metres tall.
To produce 1 ton of pig iron required :
- 1.5 tons of coal – provided heat to the furnace.
- 2 tons of iron ore – the iron in its raw, unrefined state.
- 0.5 tons of limestone – used as a flux to separate the materials.
- 5 tons of air – increased amount of air meant less fuel required to reach the high temperatures required. the air was provided by the blast engines.
The end products of this process were :
- 1 ton of molten iron – cast in the pig beds.
- 3 tons of slag waste – unusable low grade iron.
- 5 tons of waste gas – initially allowed to escape into the atmosphere but later collected and processed as secondary products.
The molten iron was poured into ‘pig beds’, so called as the long lines of furrows were said to resemble a sow feeding her piglets. The pig beds were made of sand and built by the young boys of the furnace crew. The metal was poured in to these and left to cool, after which it was cut into 1 meter lengths and then transported off the site.
The Blast Engine
There were two engines housed in the Blowing Engine House at Dunaskin, one dating from 1847 and built by Murdoch and Aitken of Glasgow and the other built in 1865 by the Lillieshall Iron Company of Shropshire. The Blast Engine provided a regulated blast of air to the furnaces, which meant more oxygen present in the furnace, reducing the amount of fuel needed to achieve the necessary temperatures for iron smelting. Both blast engines at Dunaskin worked on the same principles.
STEAM CYLINDERS (A)
|Steam from boilers alternately pushed cylinder up and down.||Front. To drive nearer end of beam.||Drove cast iron rocking beam.|
|PAIR OF CAST IRON ROCKING BEAMS (B) – APPROX 10 METRES LONG.||Alternating rocking motion – each driven by its own cylinder.||Mounted on bearings on top of cast iron entablature, directly above iron columns.||Drove piston up and down in air tub.|
|Linked to both rocking beams by long timber crank rods.||Front. Partially sunk in pit.||Regulated motion of the beams to create steady operation.|
AIR TUBS (D)
|Piston forced air into blast main.||Rear. One below far end of each rocking beam.||Produced a steady blast of air for the furnaces.|
The Brick Making Process
After the iron works closed the site was transformed into a brickworks. There had been a small brick making factory closeby in Dunaskin Glen and when the iron works closed the company took the opportunity to move to more spacious premises.
The brick making process begins with clay. Clay was mined locally from Dunaskin Glen. This was transported to the site and stored in the now-converted Blowing Engine House, which now housed a clay loft for storage and two brick presses. The Pan Mill was built behind the engine house to process the clay. In the Pan Mill were two large crushing machines which ground down the clay, removing impurities and making it better quality.
Once ground the clay was dropped down a chute, which had been made from one of the old boilers left over from the iron works period, into the clay loft in the Engine House. Clay from the loft then dropped down another chute and into the brick presses, which moulded the clay into a brick shape. The bricks were then stamped to show where they came from. The earlier bricks are all stamped DICo, which stood for Dalmellington Iron Company, whilst those produced later are stamped Dalmellington.
Once shaped the uncooked clay bricks were taken to the kiln for firing. There were two kilns at Dunaskin, on built in 1928 and the other in 1935 as the brickworks expanded. The kilns operated continuously and each kiln could hold approximately 1/4 of a million bricks. The firing process took two weeks and temperature, which was at least 1000 oC, was controlled in the kilns by a system of flues which allowed air to circulate throughout. Once the firing process was complete the bricks were taken out of The Kilns and allowed to cool and fully harden before being shipped out top their prospective markets.
The brickworks closed in 1976 and the machinery removed from the site. In the Engine House all that remains are the concrete supports for the brick presses and the remnants of the clay loft. The Kilns are still present, as is the Pan Mill, which still houses the large clay crushing machinery.
The kilns are the most dominant buildings of the brick-working phase on the site. There are two different types of kiln here, a Staffordshire Type built in 1928 and a Hoffmann Type kiln built in 1935 to cope with the additional demands on the brickworks.
The Staffordshire kiln was built by Dean, Hetherington & Co. of Accrington in 1928. It is called a Staffordshire Kiln as it is of a type popular in that county. The kiln is composed of 14 chambers, 7 on each side. 16,000 bricks were stacked in each chamber. Heat was fed into the chambers from an underfloor heating system, which saw the interior of the kiln reach temperatures of between 1100 – 1200 oC. The bricks remained in the chamber for 2 weeks to bake fully, after which time they were taken out and allowed to cool gradually. The kiln operated continuously and was used up until the brickworks closed in 1978.
The Hoffmann Kiln was built in 1935 by William Cleghorn of Newmains. This kiln consists of one long continuous chamber, divided into 24 sub -chambers by temporary walls made of wet paper. Each chamber could hold 14,000 bricks and temperatures of 1000 – 1100 oC were achieved. Each chamber opening was bricked up once firing commenced, and the firing process was again 2 weeks.