a0a2dced-180c-4abd-ace8-4f2e83fae7b4Aluminum extrusion, anodized - AEC (A1-A3)Aluminum extrusion, anodizedIndustry average, multiple producers (at plant)2500-4500 Sq. ft. per metric ton, depending on the profileAnodized aluminium extrusionSystemsConstructionThis process represents North American anodized aluminum extrusions based on primary data collected from members of the aluminum extrusion council (AEC). Overall data quality is very good.29428The data set represents anodized aluminum extrusion profiles from the USA and Canada, focusing on the main technologies and the legislative boundary conditions.The extrusion manufacturing process takes cast extrusion billet (round bar stock, produced from direct chill molds and typically ranging in diameter from 6 to 14 inches, depending on the extrusion press on which it will be processed) and produces extruded profiles. The process begins with an inline preheat furnace that elevates the temperature of the billet to a predetermined level, depending on the alloy. If not already cut to length, the billet is then sheared and placed into a hydraulic press, which then forces the semi-plastic billet through a heated steel die to form the desired shape. The length of the resulting extrusion is dictated by the take-off tables. The extrusions are air cooled or water quenched, with specific quench parameters dependent on alloy and desired properties. The extrusion is then clamped and stretched to straighten the profile. The straightened lengths are cut to intermediate or final length multiples and then typically aged in an aging oven to achieve the desired temper. Any production scrap generated during the extrusion and surface-treatment processes is collected and sent either to the company’s own cast house or to recycling facilities.
If extrusions are to be anodized, they are cleaned and etched (with either caustic or acid etch) in a series of baths. Subsequently, they are immersed in an acid electrolyte bath and an electrical current is passed through the solution. A cathode is mounted to the inside of the anodizing tank, while the aluminum extrusions act as an anode. Oxygen ions are released from the electrolyte and combine with aluminum atoms at the surface of the extrusion being anodized, thereby creating a durable aluminum oxide layer fully integrated with the underlying aluminum. Organic or inorganic colorants can subsequently be added. The final step is a sealing stage to enhance durability.ProductBecause of their many attributes and the variety of available finishing options, aluminum extrusions are useful in wide variety of products in various market sectors, including building and construction, transportation, electrical and energy, medical and consumer, machinery, military, and air.Partly terminated systemAttributionalnoneNo cut-off criteria were defined for this study. All available energy and material flow data have been included in the model. In cases where no matching life cycle inventories were available to represent a flow, proxy data have been applied based on conservative assumptions regarding environmental impacts.All primary data were collected using a customized data collection template, which were sent out by email to the data provider at the AEC member companies. Upon receipt, the questionnaire was cross-checked for completeness and plausibility using mass balance, stoichiometry, as well as internal and external benchmarking. If gaps, outliers, or other inconsistencies occurred, thinkstep engaged with the data provider to resolve any open issues.Where manufacturing inputs, such as electricity use, were not sub-metered for the individual extrusion and finishing processes, they were distributed between the different product steps based on the production-weighted average energy and water use per metric ton of those facilities that did provide data for individual processes.15.0Percentage supply or production covered: 15-20%.
Annual supply or production volume: 460,000 metric tons of anodized extrusionThe sampling procedure was self-selective, i.e., the AEC member companies volunteered to participate. Data was collected for 12 consecutive months of production to account for annual variability. The dataset is representative for the state of technology in 2015 and should be reviewed for technological change in 5 years.2015This cradle-to-gate dataset can be used as part of a full cradle-to-grave life cycle. Scrap input was left open so practitioners could apply different EoL allocation approaches. The EPDs associated with this dataset use the avoided burden approach on a net scrap basis to model the product's End-of-Life.No statementGaBi conformity systemFully compliantFully compliantFully compliantFully compliantFully compliantNot definedthinkstepthinkstep2019-02-01T00:00:00.000ILCD format 1.1thinkstep2019-02-01T00:00:00.00000.00.001Data set finalised; entirely publishedthinksteptrueOtherAluminium scrapInput0.344902766299130.344902766299130Mixed primary / secondaryMeasuredvaluableAnodized aluminum extrusionOutput1.01.00Mixed primary / secondaryMeasuredvaluable