Precautions for drawing aluminum alloy profiles

【China Aluminum Industry Network】 (1) Aluminium alloy profiles must not be rubbed, pulled, overlapped, crowded, and entangled in the process of reclaiming, moving and stretching. They should be set aside at a certain interval. For aluminum alloy profiles that are easy to bend and discharge, they must be processed in time and, if necessary, they should be protected from each other. (2) Stretching of aluminum alloy profiles must be carried out after the aluminum alloy profiles are cooled to below 50 degrees (naked hands can be gripped) before they can be moved to a stretching frame for stretching. Excessive temperatures will stretch the body and cause burns. Bad hot tops, but also because of the inability to completely eliminate the internal stress of the aluminum alloy bars before and after ageing, bending, twisting, poor performance and other waste products. (c) As the tops have a heat-resistant diffusion effect, the aluminum profiles with high decorative surface must be turned up and down before and after, in order to facilitate uniform heat dissipation and reduce the horizontal bright spot defects caused by uneven heat dissipation and uneven crystallinity, especially large Wide, thick aluminum profiles should pay attention. (4) Pay attention to the tolerances of small feet, thin teeth, long legs, arc surfaces, inclined surfaces, openings, angles, etc. of profiles with high aspect ratios, long cantilevered walls, large arcs, disparate wall thicknesses, and odd shapes. Force conditions prevent localized or point-like dimensional deformation of profiles, twisting, spirals and other defects occur. (E) The control of the amount of stretching is about 1%. For example, the tensile strength of 25M aluminum alloy profiles should be stretched by about 25CM after straightening the profile, but it must not exceed 2%. The production should be adjusted according to the actual situation of the aluminum extrusion profile discharging and various specific requirements (opening size, surface quality, external dimensions, inner diameter size, wall thickness, elongation, etc.), and seeking to be able to meet the conflicting technical requirements. At the same time to meet a variety of specific requirements of the amount of stretching. Excessive stretching results in head-to-tail size deviations, surface water-lined twists (fish scales), low elongation, high hardness, and brittleness (low plasticity). Too low tensile strength will cause the compressive strength and hardness of the profile to be low, and even the aging (quenching) will not increase the hardness, and the profile will be easily curved (commonly known as a large knife bend). (6) In order to control the amount of tensile deformation and better control the dimensional change of the entire profile, suitable special clamps and suitable methods must be used. Especially the opening material, circular arc material, cantilever material, and curved shape profile should pay more attention to the reasonable and effective use of the tensile pad. If necessary, someone should control the centering or plug pad in the middle of the stretched profile to ensure that the length of the stretch between the head and mid-segment meets the requirements of the aluminum alloy profile.