As the expansion process to increase the raw material defects, the special requirements of steel pipe expansion must meet the following requirements:
1, Tube material eddy current testing after the supply.
2, The outer surface without hair lines, folding and other defects. No delamination and other defects exist on the inner surface.
3, No glitches on the pipe end, the verticality of the required cut tangential ≤ 1mm.
4, Pipe diameter tolerance control ≤ ± 0.8% 5, pipe wall thickness tolerance control ≤ ± 10%
6, Steel spiral ≤ 0.3mm, no visible helical Road
7, The expansion of the hot end of the pipe end of the pipe expansion, hot bar end of the pipe length must be guaranteed.
