EDGE MILLING
Process that secures the weldability of SAW by milling both longitudinal edges of plates with groove type (X or Y shaped)
Step2
PRE – BENDING
Process that forms both edges of plate in their optimal curvature by using press and tool
Step3
PRESS– BENDING
Process that forms the entire body of plate in its optimal external diameter by using press and tool
Step4
GAP CLOSING PRESS ( POST– BENDING )
Process that minimizes the open gap (the distance between two edges) by using press
Step5
TACK WELDING
Process to secure the original form through fitting-up (GMAW) two edges of completely formed product
Step6
INTERNAL WELDING
Process to weld inside grooved edge of formed pipe by SAW method
Step7
LONGITUDINAL SEAM MILLING (GAUGING)
Process to remove tack welds by milling
Step8
EXTERNAL WELDING
Process to weld outside grooved edge of formed pipe by SAW method
Step9
ULTRASONIC TEST
Process to examine whether there are defects in welds (crack, air hole, slag, etc.)by using ultrasonic waves before cold expanding
Step10
FULL LENGTH COLD EXPANDER
Process that cold-expand pipe’s O.D from inside of pipe in order to calibrate pipe dimension and to reduce residual stress of pipe.
Step11
END FACING
Process to machine both pipe ends as per customers’ requirements
Step12
HYDROSTATIC TEST
Process to test pipe hydrostatically with constant pressure and holding time
Step13
ULTRASONIC TEST
Process to examine whether there are defects in welds (crack, air hole, slag, etc.)by using ultrasonic waves after cold expanding.
Step14
ULTRASONIC TEST
Process to examine whether there are defects in welds (crack, air hole, slag, etc.)by using the radiation (X-ray)
Step15
PIPE END RADIOGRAPHIC TEST
Process to examine whether there are defects in welds of both pipe ends by using the radiation (X-ray)
Step16
HEAT TREATMENT
Process to heat-treat entire pipe in order to get required properties (depending on type of heat treatment)
Step17
MILL COATING
Process that prevents corrosion by spreading inhibited oil on product surface