The aluminum profile stretch forming process has gained widespread application in the manufacturing of curved components for aerospace, automotive, high-speed rail, and other industries. In civil applications, such as aerospace and high-speed rail, many structural components utilize profile frames. Therefore, research on stretch forming technology holds significant importance in improving the quality of stretch-formed workpieces.
The stretch forming process for aluminum profiles allows for precise shaping, improved manufacturing accuracy, and reduced production costs. It involves the shaping of profiles by pressing them into a die groove under the combined action of bending moment and longitudinal tension. Aluminum profile stretch forming is an important forming technology in industrial production, especially for the manufacture of large-sized, high-precision, and large-radius curved extruded and sheet-formed profiles.
Aluminum Profile Stretch Forming Process Introduction
Incoming Material Inspection
The dimensions of the profile section, straightness of the profile, blank length, and surface quality are inspected according to the requirements. Special attention is paid to surface defects.
Milling and Cutting
For reverse T-profile frames, the profile section requires milling before stretch forming. To ensure the dimensions of the bent profiles meet the requirements, milling is performed on a gantry milling machine with dimensions adjusted to nominal value +2mm.
Pre-Stretch Forming
Pre-stretch forming of the blank is conducted using a stretch forming machine, stretch forming dies, and stretch forming jaws. The pre-stretch forming parameters, such as bending force and bending radius, are controlled to achieve the desired preforming.
Trimming
The flatness and angles of both faces are checked to ensure they meet the requirements. For R-values, auxiliary trimming can be performed using a three-roll aluminum bending machine until the desired shape is achieved.
Inspection After Pre-Stretch Forming
The flatness, angles, and section width of both faces are inspected to meet the requirements. The R-value should achieve the predetermined shape.
Transportation and Storage after Quenching
To maintain the new quenched state of the aluminum alloy material, the parts are stored at temperatures below -10°C before forming. After heat treatment, the parts are initially stored in a cold storage room and transported in refrigerated trucks with temperatures below -10°C.
Re-Stretch Forming
The semi-finished products undergo re-stretch forming using stretch forming dies and stretch forming jaws on a stretch forming machine. Re-stretch forming parameters, including stretching force and bending radius, are adjusted to meet the final requirements. During re-stretch forming, selective edge pulling and trimming may be performed based on the specific characteristics of different parts to achieve the desired shape and dimensions.
Trimming
Assisted tools such as hammers are used for trimming on a calibration platform. When necessary, correction and repair can be performed using a calibration inspection mold.
Inspection
Inspection is conducted using inspection molds, calipers, and feeler gauges to ensure compliance with customer technical and drawing requirements.
Final Finishing
Surface finishing and cleaning are performed using tools like scouring pads. Parts and samples are marked to ensure traceability.
Conclusion
The aluminum profile stretch forming process is a critical technique for producing curved components in aerospace, automotive, high-speed rail, and other industries. By employing this process, manufacturers can achieve accurate shaping, improved precision, and cost-effective production. Understanding the steps involved in the stretch forming process is essential for ensuring high-quality, properly formed aluminum profiles that meet the desired specifications and customer requirements.