Double hammer

A double hammer is a forging implement used in metallurgy. It operates on puddle balls and blooms by hitting both sides at the same time.^[1] Double hammers are made of two blocks attached to rollers which facilitate opposing movement along a set of rails.^[2] Double hammers are normally operated by three people at a time: one holding the instrument in place and the other two moving the blocks back and forth.^[3]

References

^ Robert Hunter (1883). The Encyclopædic Dictionary. Cassell, Petter, Galpin and Co. p. 171.
^ Louis Emmanuel Gruner; Lenox Smith (1872). The Manufacture of Steel. D. Van Nostrand. p. 55. double hammer metallurgy.
^ Eugene Benjamin Wilson (1905). A Manual of Mining (4 ed.). John Wiley & Sons. p. 628.

[1] Robert Hunter (1883). The Encyclopædic Dictionary. Cassell, Petter, Galpin and Co. p. 171.

[2] Louis Emmanuel Gruner; Lenox Smith (1872). The Manufacture of Steel. D. Van Nostrand. p. 55. double hammer metallurgy.

[3] Eugene Benjamin Wilson (1905). A Manual of Mining (4 ed.). John Wiley & Sons. p. 628.

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