Self inspection content:
- Stretching must be carried out on the drawing frame after the aluminum alloy profile is cooled to below 50 degrees. If the temperature is too high, the drawing will not only damage the human body and the wool top, but also cause twists and turns, twisting, poor function and other absolute waste products before and after aging due to the failure to completely eliminate the internal stress of aluminum alloy profiles.
- The control of stretching amount is controlled at 1%, and it should be noted that if the stretching amount is too high, the scale error of head, middle and tail will occur, and the appearance of water ripple like twist (fish scale) mark, low elongation, high hardness and brittle (low plasticity). If the tensile strength is too low, the compressive strength and hardness of the profile will be low, even aging (quenching) can not improve the hardness, and the profile is easy to curve (commonly known as big knife bend).
- In order to control the tensile deformation and the scale change of the whole profile, appropriate special clamp pad and appropriate method should be selected. In particular, the opening material, arc material, cantilever material, as well as the bending shape of the profile should pay more attention to the reasonable and useful use of stretch clamp pad.
- Pay attention to the stress conditions of small feet, thin teeth, long legs, arc surface, inclined surface, opening and viewpoint of profiles with high width thickness ratio, long cantilever wall, large radian, great wall thickness difference and strange shape, so as to avoid the defects such as deformation, twisting and spiral of section or point scale.
- Due to the heat blocking effect of wool top, the aluminum profiles with high demand for decorative appearance must be turned up and down, back and forth, so as to facilitate uniform heat dissipation and reduce the transverse bright spot defects caused by uneven heat dissipation and different crystallinity. Especially for aluminum profiles with large width and thick wall, more attention should be paid to them.
- In the process of reclaiming, moving and stretching, it is not allowed to touch, pull, stack, jam and entangle with each other, and a certain space shall be reserved between them. The aluminum alloy profiles with easy twists and turns and the length of discharge shall be disposed in time, and the maintenance and disposal between them shall be done when necessary.
Self test range:
- Before processing, the processor must clearly see the content of the process card, clearly know the parts, shapes and dimensions of the workpiece to be processed, and know the processing content of the next process.
- Before clamping the workpiece, the blank size should be measured to see if it meets the requirements of the drawing, and the placement of the workpiece must be carefully checked whether it is consistent with the programming operation instruction.
- Self inspection should be carried out in time after rough machining, so as to adjust the data with errors in time. The self inspection content mainly includes the position and size of the processing parts. For example:
(1) Whether the workpiece is loose;
(2) Whether the workpiece is correctly divided;
(3) Whether the dimension from the processing part to the reference edge (reference point) meets the drawing requirements;
(4) The position and size between the processing parts. After checking the position and size, measure the rough machined shape ruler (except arc).
- After rough machining self inspection, finish machining is carried out. After finishing, the workers should check the shape and size of the processing parts: check the basic length and width of the vertical processing parts; measure the base point size marked on the drawing for the processing parts of the inclined plane.
- The worker can remove the workpiece and send it to the inspector for special inspection after completing the self inspection of the workpiece and confirming that it meets the drawing and process requirements.
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