There are two main classes of profile –solidandhollow: solidprofiles are produced using a flat, disc-shaped die.
Dies for solid profiles hollowprofiles are produced using a two-part die. In hollow dies, the mandrel (the part that shapes the cavity in the profile), is supported on a bridge. during extrusion, the metal separates around the bridge. the other part of the die shapes the outer contour of the profile.
large and medium-sized profiles are pressed through a die with only one aperture. smaller profiles can be advantageously pressed through multi-apertured dies – there may be as many as 16 apertures.
die lifetime depends on the shape and desired surface quality of the profile.
Hollow profile extrusion uses a mandrel to produce the cavity