Why the Residual air in extruded aluminum profiles?

- May 15, 2019-

The main factor of residual air inside extruded aluminum profiles

When the extruder is pressurized, there will be residual air in the aluminum profile, resulting in bubbles in the interior and exterior of the aluminum profile. Defects that cannot be completely solved will turn the aluminum profile into waste. In order to prevent air from entering the aluminum, it is important to find out the reason why air is brought in. According to nanfang aluminum, the main factors causing residual air inside the extruded aluminum profiles include:

The hot shears of the rods caused the residue of air

The shear plane formed by the hot shearing of long bars is by no means perfect. The simple hot shearing of vertical industrial aluminum profiles will result in the serious bending of the bar, resulting in an elliptic cross section of the aluminum profiles and a very large rounded corner at the end of the shearing. Even with the latest type of long rod hot shears, the Angle of the edges of the sheared rods always produces inverted circles, which are the best places for air to remain.

Only if the diameter of the tube holding the aluminum ingot is larger than the diameter of the rod. The rods are large enough to be put into a canister containing the aluminum ingots. The gas must be vented after pressure is applied to the rod inside the aluminum cylinder causing the rod to expand to the diameter of the cylinder. When the gas is not released, it remains inside the aluminum ingot and eventually becomes a bubble.

Because the surface of the two studs is essentially flat and the probability of carrying air in is very small. The quality of the sawing directly interferes with the amount of air carried between the two studs. At present, a new high technology is available to prevent two short rods from joining. To eliminate the possibility of air entry.