Spinning cracks
Common causes: coarse grains, insufficient extension; if a small part, titanium wire may be missing; slag inclusion; inaccurate specifications of customer orders.
Parabolic lines
Common causes: It is not clear yet, and it occurs frequently in spun aluminum products (such as aluminum pots, etc.). Generally, the lines will weaken but will not disappear after later polishing. In severe cases, cracks will occur along the lines. If performance problems are excluded, the main consideration is whether the aluminum disc is too thin;
Edge adhesion
Generally, it is an error in the production operation of aluminum discs, which is a completely avoidable problem. Causes:
1) It usually occurs mainly in large-diameter aluminum circle discs (D≥780 mm);
2) Workers take shortcuts when manually marking circles, stacking 2-3 aluminum plates and operating at the same time, causing the edges of the discs to be pressed together under the action of external bite force, and then the slight burrs on the edges melt in the high temperature of the annealing furnace, resulting in edge adhesion. However, the workers did not pay attention to the thickness difference of the same stack of products during the later packaging, resulting in the goods being shipped. When the customer used it, they found that the material was too thick. Only after polishing the edges did they find that it was actually multiple aluminum discs glued together.
3) The splitting process is time-consuming and labor-intensive, and the aluminum discs are severely deformed, so most of the materials that are glued to the edges must be discarded.
Center pit
Problems associated with the production process. Reasons:
1) It mainly occurs in large-diameter and slightly thin aluminum discs (D ≥ 780 mm, thickness less than 1.5 mm);
2) The indentation caused by the rounding machine shaft when fixing the aluminum plate during the production process. Generally, it can be automatically leveled during the spinning process, and there will be no traces on the bottom of the finished pot.
3) You can try to wrap the bottom of the fixed shaft so that it does not directly contact the surface of the aluminum plate. However, if O-temper material is used for rounding, pits are inevitable.
STRETCH MARKS
Generally, this type of pattern is a roller mark, which has no hand feel, and the customer will disappear with the spinning process in the subsequent processing and production, so the aluminum products such as aluminum pots produced will not be affected.
Wrinkle indentation
Generally, there is an obvious hand feel, but it occurs in small quantities. Generally, there are indentations in the head and tail parts, which are not completely picked out in the packaging and are unqualified products. Aluminum products such as aluminum pots manufactured later will also have wrinkles and indentations.
Warping/unevenness
1) Head and tail materials, which have defects themselves, but in small quantities;
2) O-state materials, especially large-diameter aluminum discs, are easy to deform during lifting.
3) H12 state, due to external force during transportation, the friction and collision between the two stacks will cause edge deformation if the packaging is not tight;
4) Generally, it does not affect the subsequent processing.
Finished product square edge
1) This type of problem is also a common problem in the spinning/deep drawing of cast and rolled materials, which is closely related to the performance of the cast and rolled materials themselves, especially when the earing rate of the material is high. It is temporarily believed that it is related to the difference in the internal performance of the material in different directions.
2) It can generally be solved by trimming in the later stage.
Packaging water erosion
1) Generally occurs when the sea transportation time is long or the detention time in the middle loading port is long;
2) If the packaging is not damaged, it is known that the aluminum disc will not be affected within 3 months;
Transport damage
1) When the stack is misaligned, the top plate of the bottom layer is easy to break, which generally does not cause obvious damage to the goods. There may be a small indentation on the top of the bottom layer;
2) In case of LCL packaging, the factory is required to strengthen the packaging as much as possible, and retain photos before shipment to prove the status of the goods. At the same time, remind customers in advance that if the packaging is damaged when picking up the goods, stop picking up the goods and be sure to contact the insurance company as soon as possible to collect evidence before picking up the goods;.
