Hot uncoiling of metal
A system for heat-treating a coil of metal can include a furnace, an unwinding system, and a quenching system. The furnace may receive the coil of metal and elevate a temperature of the metal to be within a pre-heated temperature range, such as a homogenizing temperature range or an annealing temperature range. The unwinding system may unwind at least a portion of the coil in a heated state in which the metal is within the pre-heated temperature range or before the metal has cooled past a threshold amount below the pre-heated temperature range. The quenching system may receive the unwound portion of the coil from the unwinding device and reduce a temperature of the unwound portion to a within a quenched temperature range within a predetermined amount of time.
1 . A method for heat-treating a coil of metal, the method comprising:
heating the coil of metal within furnace heating section of a furnace to elevate a temperature of the metal to be within a pre-heated temperature range corresponding to a homogenizing temperature range or an annealing temperature range;
unwinding the coil of metal in a heated state in which the metal is within the pre-heated temperature range or before the metal has cooled past a threshold amount of 50° C. or less below the pre-heated temperature range, wherein the unwinding produces an unwound portion of the coil;
between the heating of the coil and at least a part of the unwinding of the coil, transporting the coil between the furnace heating section that performed the heating of the coil and an unwinding location; and
quenching the unwound portion of the coil to reduce a temperature of the unwound portion to a quenched temperature range within a predetermined amount of time less than 20 seconds, wherein the quenching produces a quenched portion.
2 . The method of claim 1 , wherein the heating, unwinding, and quenching are performed with the coil maintained in a continuous band of material without the band being subject to severing and re-connecting.
3 . The method of claim 1 , further comprising:
re-coiling the quenched portion into a second coil.
4 . The method of claim 1 , further comprising unloading the coil from the furnace from below or beside the furnace.
5 . The method of claim 1 , further comprising at least partially encasing the coil with insulation material to reduce heat loss during the transporting of the coil.
6 . The method of claim 1 , further comprising:
inserting a mandrel into a spool about which the coil is formed, wherein the inserting of the mandrel occurs before the heating of the coil, and wherein the mandrel is configured to radially expand for adapting to a change in size of an inner diameter of the spool resulting from the heating of the coil; and
rotating the mandrel, wherein the unwinding of the coil results from the mandrel rotating.
7 . The method of claim 1 , wherein the metal comprises aluminum.
8 . The method of claim 1 , wherein the pre-heated temperature range corresponds to a homogenizing temperature range between 400° C. and 600° C.
9 . The method of claim 1 , wherein the pre-heated temperature range corresponds to an annealing temperature range between 300° C. and 500° C.
10 . The method of claim 1 , wherein the quenched temperature range resulting from the quenching is between 200° C. and 500° C.
11 . The method of claim 1 , wherein the quenched temperature range resulting from the quenching is between 200° C. and 350° C.
12 . The method of claim 1 , wherein the quenching comprises subjecting the unwound portion of the coil to a quenching medium provided in a quenching temperature range between 100° C. and 250° C.
13 . The method of claim 1 , wherein the quenching comprises subjecting the unwound portion of the coil to a quenching medium provided in a quenching temperature range between 10° C. and 200° C.
14 . The method of claim 1 , wherein the quenching corresponds to a heat extraction rate greater than 10° C./s.
15 . The method of claim 1 , wherein the quenching corresponds to a heat extraction rate less than 100° C./s.