Experimental IRON SMELTING

Norse Bellows Air
 
How did the Norse during the Viking Age make iron blooms from bog ore?
Experimental Archaeology can give insight into the techniques used in Northern Europe to operate direct reduction iron smelting furnaces.
This is a record of the ongoing series by Darrell Markewitz,
assisted by members of the Dark Ages Re-creation Company.

A specific element of historic iron smelting methods is that of air supply. For the Norse this especially a problem, as there are no surviving artifact bellows of any kind. There are only a couple of illustrations known depicting bellows, and those related to blacksmithing, not iron smelting. These images show a pair of individual chambers, linked to a single output. The operator is seen alternating the action, raising and filling one chamber while the other is collapsed and providing blast.

Drawing of the Ramsund Stone Carving (1030?) Sweden	Wood Carving (c 1150?) Hyllestad Stave Church  - Norway

Along with investigations into the underlying physical methods, and specific regional variations, this team has undertaken experimental use of several bellows constructions based on the Norse model.

Blacksmith's Bellows (several variations used) E 120 LpM (@60 strokes / minute)	Ubber Bellows E 700 LpM (@60 strokes / minute)	Smelting Bellows E 425 LpM (@60 strokes / minute)

Generally, the tests of Viking Age Bellows / Air would overlap with other test series. The Blacksmith's bellows was used 4 times, plus once in combination with a bladder. The Ubber Bellows was used only 3 times, as it was found too punishing for workers. The Smelting Bellows as used 6 times, plus partially for 2 others. The standard electric blower was used twice at reduced volume (to mimic measurements from the Smelting Bellows. This blower limited both in volume and by a sliding gate to mimic the plusing delivery flow from Norse twin bellows equipment was used 4 times.

Commentaries on Norse Bellows Air