The Process utilizes the latest technology and modern
equipments for producing high quality Spiral Weld Pipes.
HR Coils are loaded on the
decoiler of the Spiral Pipe Mill. The strip is straightened and 100% coil
width wise is examined for any defects in the material by automatic ultrasonic
unit having of 36 Probes & 144 Channels.
The edges are milled to desired joint
geometry. The strip is guided into the forming station, where it is formed to
produce cylindrical hollow body at predetermined forming angle, ensuring the
proper welding gap between the abutting edges, inside and later, outside
welding is performed by an automatic submerged arc process.
After accomplishment of inside
and outside welding, flux and slag from inside the pipes is cleaned. Pipes are
cut to a predetermined length by an automatic plasma arc cutting device. The
entire weld seam is scanned and visually displayed for analysis of all the weld
defects. If any in the weld seam by Fluoroscopic inspection / Real Time
Radiography.
At the end facing machine, both
ends of pipes are machined simultaneously to suit joint to be used on the pipe
line. Each pipe is hydrostatically tested to a given pressure as per API 5L
specification or other desired specification.
Full weld length of pipe type HAZ is examined by
automatic ultrasonic unit with the help of 16 Probes and 16 channels for
checking the weld defects. At the X-ray station, radiographs are taken of weld
seam for each pipe end to a distance of 4". Every length of pipe is
subjected to a rigorous check at the final stage before it is accepted by the
Quality Control Dep’t.
