Anodize Quality Control

Anodize - Color Check

A rigorous, on-line quality assurance program is conducted before any material is allowed to leave Linetec.

A Linetec QC associate visually checks the anodized aluminum for flaws and color variations, comparing the metal to a set of internal control samples. The control samples consist of two samples which represent the extremes of appearance to be expected on the finished components.
Anodize line control room

A computer-automated system controls and monitors product through the entire anodizing process.

The system tracks all aspects of the process including tank sequencing, time, temperature, voltage, current, etc. The computer controlled hoist system ensures all material with the same job and process specification is moved through the same solutions for the same amount of time.
Anodize lab

The anodizer is responsible for providing adequate testing and sampling to insure the production quality meets the AAMA611 test requirements.

Laboratory testing includes checks for coating weight, seal quality, anodic coating thickness and several other criteria. Test records are kept on file, with the production date for a minimum of five years.
Prints & Exposures

Up to date die drawings with accurate marked exposures is critical to a coating applicator.

Linetec defines an exposed surface (exposure) as the surface area indicated on a material shape that requires finish coverage. An exposed surface area, when assembled into doors, windows or other assemblies, is either viewable or in direct contact with environmental weathering.

When material is anodized, accurate exposed surfaces must be supplied even though the entire part is immersed in all the process tanks. Whenever possible, material is welded, clamped or racked on surfaces that are not exposed. Material is racked at an angle to help prevent gas-out onto exposed surfaces.

Square footage is calculated based on a parts total exterior perimeter. The square footage of a full load of anodize racked material is used to determine the time required in the anodize tanks to achieve a specific color. Inaccurate square footage can cause partial or complete job discoloration, which would require another production run and could decrease overall material thickness.

Calculation for an anodize exposure, per lineal foot, is calculated using the total perimeter of the shape. For non-extruded parts, all exterior surface dimensions are summed to determine the exterior perimeter.

Square footage is calculated by multiplying the exposure by the total lineal footage of the profile.

For hollow material, exposure and square footage calculations are based on the parts complete exterior surface. Interiors of hollow surfaces are not included in the exposure because the electrical current does not pass inside the hollow.