Sunday, May 16, 2010


This is the first part it what will likely be a long series on the construction of my open hearth facility.  The benchwork for this section just went up this weekend.  When finished, I will have approximately 24"x84" to build my steel making plant, or rather, a representative of it.  The idea is that my mill has a 12 - 100ton furnace open hearth plant.  Not having the room to model all of this, I will be able to fit 6 furnaces and the metal mixer in the space I have.   I also will only be able to model about half the mill crosswise.   I am taking somewhat of an unique turn  in that I am modeling the charging side of the mill.  Most models I have seen focus on the pouring side of the plant.  I chose the charging side for a few reasons - first I felt the interior of the furnace building would be eaiser to model from the charging side and presents the opportunity to model some rarely modeled contraptions.  Second, it will allow me to use my narrow gauge scrap cars in operations.  And Finally, I will be able to model gas producers.
Wait a sec - what are gas producers?  Gas producers were fairly common prior to the mid-1950s when they were phased out in most plants.  Not unique to steelmaking, they were used in greater proportions in this industry because of its need for gas for heating a variety of furnaces and ovens to high temperatures.  Basically, a gas producer is a 12' round sealed steel vessel that is fed with coal (or most any combustible) from the top and a blast of air/steam from the bottom.   The result is a combustible gas that exits through the top of the vessel through a pipe and into a main.   Usually producers are found in banks or groupings.  These were almost always the source of gas for non-integrated steel facilities - such as a stand alone, open hearth or foundry or rolling facility, but even in integrated mills they appear to be used frequently in the open hearth plants and reheat furnaces.  I'm not exactly sure whether there was not enough gas from the blast furnaces and coke works to go around, or it was for some other reason.   Whatever the reason it appears that by the mid to late 1950's these devices had either become too inefficient or costly to run and were replaced in most cases by blast furnace/coke gas supplemented with fuel oil.
From a modeling standpoint these gas producers open up a bunch of variables that will had interest to everything from modeling to operations.    In the case of my open heart plant - the 12 furnaces would need 36 gas producers in six banks of six to provide enough fuel.  Since I am modeling only half the plant, I will need to model 18 producers in three banks - lots of intense modeling, but in a small package.  This is what is neat about these things too - typically the buildings that housed them were only 20 feet or so wide, so they don't use up much real estate. For operations there is another destination for coal - anthracite or bituminous, and some reverse traffic in the form of ash.   Thirty six producers would consume 54 tons of coal an hour - so for an operating session that represents six hours - I would need 6 hoppers of coal.  For the ash produced in the process - 6 tons per hour, or one gondola or hopper every other operating session (or could just pull a light load every session for disposal on company grounds) 
Much more on all this to come soon.  Plus, the Bessemer plant will also be going up too at a different location.  

Note on the benchwork - nothing fancy in it's construction but as I think I have posted before, I avoid pine at all costs and use 3/4" maple plywood ripped into 3" strips.  It is much more dimensionally stable and doesn't split when you put screws into it.

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