At the Supplier factory , they tried to remove mill scale by hand polishing pipe.
Hand polishing cause scratches on surface of pipe.
Mill scale occur in annealing process and it was not completely removed by
pickling process.
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We confirm with the supplier that Mill scale doesn't affect mechanical property of pipe.
We didn't receive information about mill scale at the time of shipment.
the supplier will inform us countermeasure against this issue,
We will inform you as soon as we receive further information from them.