 |
There isn't much more I can say about the Siemens brothers, the Martins,
or the Siemens-Martin regenerative open hearth
furnace on top of what you find in the links. |
|
 |
The "details" and how it developed easily fill a book. So I just show
some pictures instead.
Here is a nice schematic drawing that shows the operation quite clearly (if very simplified): |
| |
| |
| |
|
 | | Siemens-Martin process |
| Source: Internet |
|
| |
| |
|
|
Here is the real thing |
| | |
|
|
|
 | | Charging a Siemens-Martin furnace |
| Source: Internet at large; origin of picture unclear. |
 | | Tapping a Siemens-Martin furnace |
| Source: Internet |
|
| |
| |
|
It is clear that for tapping you needed an opening that could be opened and closed
from the outside - with liquid iron in the inside. Not an easy thing to construct and I don't know how it was done. |
|
|
Below is picture of an actual hearth from the Clydebridge steel works in England, now a kind
of museum. Unfortunately, the tapping mechanism is not shown. |
| | |
|
|
|
 | | The hearth of a (big) Siemens-Martin furnace |
| Source: Clydebridge Iron Works Museum site |
|
| |
| |
|
|
Finally, a modern Siemens-Martin furnace - actually the last of its kind.
It's shown in the Industry Museum in Brandenburg an der Havel, Germany. When it closed down in 1993, the era of the Siemens-Martin
furnace was finally over. |
| |
| |
| |
 | The very last Siemens-Martin furnace
Large size |
| Source: From the Internet pages of " Peter-Berlin" Berlin, Deutschland. Thanks,
Peter! |
|
| |
| |
|
Are there any problems with the Siemens-Martin process? You bet. It is too slow.
Good old Bessemer / Thomas could transform 5 tons of pig iron to steel in 30 minutes! Siemens-Martin, with all its advantages
couldn't beat that. Making 300 ton or so at one go is nice - but it takes time and is not very flexible. So find a way to
keep the advantages of the Siemens-Martin process but with the speed of the old Bessemer / Thomas process. |
|
|
That is what oxygen
blasting or the electric arc furnace processes
do (up to a point). A kind of renewed Bessemer - type of processing, just with oxygen instead of air and all the modern
real-time analytics implemented, simply is cheaper per ton of steel produced. |
| |
| |
© H. Föll (Iron, Steel and Swords script)
10.5.3 Making Steel after 1870 
With frame