Spiral steel pipe - bearing knowledge main quality indicators

Project delivery pipe GB/T9711 - 1997 SY / T5037 - - - - - - - 2000 SY / T5038 - 92 tube outside diameter deviation D< 508±0. D D≥508±1 75%。 d D< 00%; 508±0. 75% D D≥508±0。 d±1 50%。 25% D D< wall thickness deviation; 508 + 15. t - 0% 12. 5％t D≥508+17. t - 5% 10. 05t D< 508±12. 5％t D≥508±10. 12 t±0%。 More than 5% t weld high 3 or less. 18毫米0。 5 - 3. 0 mm within 2 or less. 0 mm outer 2 or less. 5 mm straight degree 0 or less. 2％L ≤0. 2％L ≤0. 25% slope Angle 30 L tube form & ordm; - - - - - - - - - - - - 35º Blunt edge 1. 59±0. 79 mm cut oblique 1 or less. 59 mm slope Angle 30 & ordm; — 35º Blunt edge 1. 6±0. 8mm D< 813 slice helical 1 or less. 5 mm D p 813 oblique cutting 3 or less. 0 mm slope Angle 30 & ordm; — 35º Blunt edge 0 - - - - - - 3 mm cut oblique 1 or less. Within 5 mm NDT is 203 mm from the pipe weld using X-ray inspection; Is 203 mm from the pipe outside of weld ultrasonic testing; Butt weld, repair welding seam and circular weld ultrasonic testing butt weld, repair welding and ring to weld using X ray and ultrasonic inspection; Every 10 root steel pipe smoking two root steel tube of the spiral weld x-rays or ultrasonic inspection butt weld, repair welding and circular weld ultrasonic testing water pressure test P = 2 [ σ] t / D P = 2 ( σ] t / D P = 2 ( σ] T/D note D: steel pipe nominal diameter, mm; T: nominal pipe wall thickness, mm; ( σ] : MPa hydrostatic pressure test of test stress; L: single pipe length, mm; P: hydrostatic test pressure, Mpa