Lamination defect control measures of spiral steel pipe is following below:
Improve the cleanliness of molten steel, to reduce the harmful inclusions; increase the proportion of the slab crystal axis, to reduce the center segregation and center porosity; the use of reasonable cooling system to avoid cracks occur within the slab; billet or rolling slab to be taken offline slow cooling process, reduce internal stress, thus ensuring the microstructure and mechanical properties of the finished tube and pipe meet the technical standards.
By measuring the thermoplastic curve, choose the best heating temperature. Note also that there is enough heating tube holding time, in order to reduce and improve plastic deformation resistance and toughness.