UNCOILING
Process to supply skelp to forming process by uncoiling the wound skelp
Step2
LEVELING
Process to flatten the uncoiled skelp
Step3
EDGE MILLING
Process that secures the weldability of ERW by milling both longitudinal edges of skelp with square-shape(I type)
Step4
FORMING
Process to transform a flat skelp into a round pipe and to prepare edge alignment for welding
Step5
WELDING
The edges of the skelp are heated by high frequency welding and are squeezed together by pressure.
Step6
HEAT TREATMENT
Process to heat-treat welds of pipe by using inductors (Normalizing)
Step7
COOLING
Process to cool the normalized welds by air and water
Step8
SIZING
Process to calibrate pipe dimension as per customers’ requirements
Step9
CUTTING-OFF
Process to cut the pipe length as per customers’ requirements
Step10
END FACING
Process to machine both pipe ends as per customers’ requirements.
Step11
HYDROSTATIC TEST
Process to test pipe hydrostatically with constant pressure and holding time.
Step12
ULTRASONIC TEST(SEAM & FULL BODY)
Process to inspect welds and base metal of pipe by using ultrasonic waves
Step13
MILL COATING
Process that prevents corrosion by spreading inhibited oil on product surface
Step14
DIMENSION / VISUAL INSPECTION / PACKING
Process that packages and decides the acceptance/refusal by confirming the size of the final product and exterior condition