Extrusion Process

The Extrusion Process begins with the billet, the raw aluminum material that is used to extrude aluminum shapes.  The billet is a cylindrical shaped log that is cast from pure aluminum and small percentages of iron, magnesium, copper, silicone, manganese, zinc, chromium and other elements to form an aluminum alloy.  The logs are delivered and cut to size depending on the shape and the weight per foot of the part.  The aluminum billet is placed in a billet heater that will take the billet to a soft state (approximately 900° F) so it can be extruded through the die.  The heated billet is placed into a billet loader and in the extrusion press container.  The Extrusion ram is forced through the container pushing the billet into the die and out of the die onto a run out table where it is cooled to room temperature.  This process can be visualized by imagining a tube of toothpaste, or a cake decorator and squeezing the tube until the toothpaste, or icing comes out of the opening.

The opening of the toothpaste, or cake decorator having a selected design on the end will result in the extruded paste or icing coming out in the shape of the design.

This photo shows a new length of extrusion just emerging from the press.  The die has four cavities that allow identical shapes to be extruded at once.  

The metal is cooled on the cooling table and moved to the stretching operation, where it is stretched to straighten and remove any deformities caused by the cooling process.  The next step is the cutting operation that produces the required length of the extruded shape for further processing or finishing.  The aluminum is still in a soft state as it is cut to size and must be heat treated to give it the required mechanical properties.  The heat treating process allows the aluminum to be artificially aged by taking the aluminum up to a certain temperature (approximately 350° F) for an extended period of time and cooling the aluminum down to room temperature.  The aluminum is now in a hardened state and ready for the next process that may include finishing, fabrication or final assembly.

This diagram shows the basic steps involved in extruding an aluminum profile.

Packing and Shipping

Aluminum profiles can be packaged in a variety of ways from bare batten bundles to cardboard surround, paper interweave to wood crates.

PACKAGING

After heat treat, the extruded shapes are moved to the packing and fabrication departments for finishing or fabricating, or to be packed and prepared for shipment to the customer.

Most extrusion plants are equipped to accommodate any likely packaging requirement.  Extruded shapes are packed and palletized in various way to protect them from surface damage, twisting, or other severe hazards.  Some Customers will specify their own packaging requirements, or the type of extruded product may need a special or particular method of packaging for ease of storage and/or delivery.  Delivery of the extruded shapes is accomplished by company owned tractor trailers, or by common carrier, whichever is more convenient or less costly.

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Iowa Aluminum, Inc.  ~  10-27th Ave. East  ~  PO Box 306  ~  Albia, IA 52531

Phone:   641.932.7410  ~   Fax:  641.932.5381