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Posted 11/07/2022 6:03 pm
To answer to all: "Ragged Clips" is what errors site named those rolling errors, I say errors because metallurgical are considered errors.
This it is the really explanation of this ALLEGATORING error on the rolling and planchet: non-homogeneous flow of material
thanks for attention
PS: There are four main metallurgical processes for the manufacture of finished metallic products where the metal products can pick up defects. The defects picked up during these processes are
1. casting defects,
2. rolling defects,
3. forging defects,
4. welding defects.
Quote:
Edge cracks occur if rolls have excess convexity. They occur when the center of the metal sheet has more elongation than the edges. This leads to a defect called center buckle. Edge defects are due to heavy reduction. Small thickness sheets are more sensitive to roll gap leading to greater defects. Thin strips are more likely to undergo waviness or buckling.
During rolling, the metal sheet has a tendency to deform in lateral direction. Friction is high at the center. Therefore, spread is the least at the center. This leads to rounding of ends of the sheet. The edges of the sheet are subjected to tensile deformation. This leads to edge cracks. If the center of the sheet is severely restrained and subjected to excess tensile stress, center split can happen. Non-homogeneous material deformation across the thickness leads to high secondary tensile stress along edge. This leads to edge cracks. Secondary tensile stresses are due to bulging of free surface.
Due to non-homogeneous flow of material across the thickness of the metal sheet, another defect called ALLEGATORING occurs. This is due to the fact that the surface is subjected to tensile deformation and center to compressive deformation. This is because greater spread of material occurs at the center.
Edge cracks occur if rolls have excess convexity. They occur when the center of the metal sheet has more elongation than the edges. This leads to a defect called center buckle. Edge defects are due to heavy reduction. Small thickness sheets are more sensitive to roll gap leading to greater defects. Thin strips are more likely to undergo waviness or buckling.
During rolling, the metal sheet has a tendency to deform in lateral direction. Friction is high at the center. Therefore, spread is the least at the center. This leads to rounding of ends of the sheet. The edges of the sheet are subjected to tensile deformation. This leads to edge cracks. If the center of the sheet is severely restrained and subjected to excess tensile stress, center split can happen. Non-homogeneous material deformation across the thickness leads to high secondary tensile stress along edge. This leads to edge cracks. Secondary tensile stresses are due to bulging of free surface.
Due to non-homogeneous flow of material across the thickness of the metal sheet, another defect called ALLEGATORING occurs. This is due to the fact that the surface is subjected to tensile deformation and center to compressive deformation. This is because greater spread of material occurs at the center.
This it is the really explanation of this ALLEGATORING error on the rolling and planchet: non-homogeneous flow of material
thanks for attention
PS: There are four main metallurgical processes for the manufacture of finished metallic products where the metal products can pick up defects. The defects picked up during these processes are
1. casting defects,
2. rolling defects,
3. forging defects,
4. welding defects.
Edited by silviosi
11/07/2022 6:08 pm
11/07/2022 6:08 pm
