Spirally Welded Steel Pipes
Step 1
Hot rolled steel sheets are subjected to required measurement control as well as mechanical and chemical testing to ensure compliance with the applicable standards followed by sheet number and sheet acceptance labeling before being transferred to the stockyard.
Step 2
The rolls received in the stockyard are cut to a certain width in line with the diameter of the pipes to be manufactured as required, and then they are transferred to the production area.
Step 4
Forming rollers shape the steel sheet corresponding to the required pipe diameter into a spiral form, and it is joined using the shielded welding method first from the inside and then from the outside.
Step 3
After all the required tests and cutting are completed, if necessary, sheet sides are milled (the welding end is drilled) to ensure a high-quality welding structure prior to turning the sheet into a spiral form.
Step 6
The spiral welded steel pipes, which ensure continuity thanks to their spiral form and allow for the attachment of additional sheets, are cut in length as required by the applicable specifications and/or standards.
Step 5
During the production process, pipe surface lamination and welding control are carried out online using the ultrasonic method.
Step 7
The initial visual inspection of the material cut and formed into a pipe is carried out. This stage ensures that the pipe’s dimensions correspond to the required dimensions in addition to providing initial visual inspection against visible defects.
Step 8
Welding ends are drilled at the pipe ends in line with applicable standards to reduce site application processes and ensure high-quality welding.
Step 10
The pipes undergo radioscopic testing/control by X rays as required by customer specifications and applicable standards.
Step 9
The pipes drilled with welding ends are then subjected to hydrostatic testing based on pressure values as defined in accordance with customer specifications and applicable standards by taking into account operating pressures.
Step 12
The final visual inspection of the pipes, all processes of which are monitored by a computer and barcode system using ID numbers, is performed. The pipes required to be provided with insulation as per the relevant specifications are delivered to the relevant coating hall whereas bare pipes are transferred to the stockyard after branding.
Step 11
Following the successful completion of all these stages, the pipes are inspected in accordance with a quality plan issued based on customer specifications and applicable standards at the final control station.