Phase 3 1900
A postcard dated December 1903 illustrates the next development at the ironworks.
Around 1900, Edward Barton's son, Albert, visited plants around the ironmaking district of Birmingham, Alabama, USA, and on his return it was decided to modernise and uprate the No6 furnace. In 1902 the No4 and No5 furnaces and lift were demolished and No6 modified with mechanical charging equipment and the original Player pipe stoves replaced with Cowper hot blast stoves. There were other changes in the blower house - all designed to increase blast pressures and raise output to around 1500 tons per week.
Furnaces 1,2 and 3 still hand charged via the (left) lift. The remaining (right) lift was redundant and the old No6 furnace was renumbered 1a (mainly to confuse researchers and historians).
The hoist ran from the weigh house just beside the bunkers to the furnace top without manual intervention. The Cowper stoves were taller than the Ford & Mancur type and were linked by a lightweight access gantry and accessible from the furnace top or a spiral staircase around the stove.
In 1903 new self discharging slag ladles were introduced. Tracks on the West side of the furnaces were rearranged to accommodate two per furnace. 1903 also brought two new wood built cooling towers and a new pond for recirculating cooling water.
A hand coloured postcard view of a typical Birmingham AL. blast furnace plant reveals what Albert probably experienced on his travels. It dates from 1915 which is a little later, but shows the furnace on the right with a skip hoist charging and bell arrangement. The furnace on the left is an earlier open topped design like Carnforth's. The flat topped structure that appears to be on the furnace top is the top of the lift, beyond the furnace. It is unusual to see a full height spiral staircase to the left.
This cover from the Scientific American journal of 1902 is probably quite close to the design of furnace 1a. The ERIE railroad gondola is standing on a substantial wooden trestle leading to the coke bunker. An ironworker is shovelling coke around the almost full bunker.
It is a single skip design, which must have been fairly shortlived when twin track hoists could service the same furnace more efficiently. This is a particularly fine illustration, revealing the furnace top gear very clearly.
It still appears to be a single bell arrangement, allowing a loss of gas and blast pressure when the bell was opened.
Downcomer to the right and Cowper stove barely showing on the left. The downcomer directs gas to a larger diameter dust catcher, partly obscured by the railroad gondola.
Below is Carnforth Furnace 1a for comparison
High above the furnace is the counterbalanced beam and steam cylinder for operating the bell, and the curved tracks at the top of the hoist which guided the skip wheels during dumping. The Cowper stove was reached from the furnace top or the spiral staircase. There is a single off-take, downcomer, dust collector, horizontal hot and cold blast mains, and a mixture of older and newer iron ore hopper wagons standing over the bunkers. (1) The tall thin pipe rising vertically up from the downcomer is the bleeder. The bleeder valve is just about visible at the top. Before lowering the bell to admit a new charge to the furnace, the counterbalanced bleeder valve was opened to relieve the gas pressure at the top of the furnace. This prevents the escape of gas and flame from the furnace throat.
The large diameter horizontal pipes above ground level are the hot blast main and the cold blast main. You can see the bustle pipe circulating the base of the furnace which delivered the hot blast.
The spiral staircase around the stove is not connected to the inclined skip hoist, even though it looks aligned. It is just a quirk of the camera position that makes it appear linked.