The manufacturing method determines the characteristics of the pipe, Therefore the classification of pipes are based on the manufacturing process, the various classifications are: Seamless Pipes & Seamless Tubes: A heated billet is brought into contact with tapered revolving rolls in such a way that the billet is pulled into the space allowed between the rolls. The mandrel is placed in the space. The soft centre of the billet makes it possible for the rolls to draw the billet over the mandrel, producing a hollow shell. When the billet has entirely passed over the mandrel, it is in the form of a thick walled seamless tube. The heavy walled tube is then passed to a rolling mill which reduces the tube to piping of proper outside diameter and wall thickness. Depending upon the process condition (temperature), seamless tubepipes is termed as Hot Finish Seamless or cold drawn seamless as the term implies.

The manufacturing method determines the characteristics of the pipe, Therefore the classification of pipes are based on the manufacturing process, the various classifications are: Seamless Pipes & Seamless Tubes: A heated billet is brought into contact with tapered revolving rolls in such a way that the billet is pulled into the space allowed between the rolls. The mandrel is placed in the space. The soft centre of the billet makes it possible for the rolls to draw the billet over the mandrel, producing a hollow shell. When the billet has entirely passed over the mandrel, it is in the form of a thick walled seamless tube. The heavy walled tube is then passed to a rolling mill which reduces the tube to piping of proper outside diameter and wall thickness. Depending upon the process condition (temperature), seamless tubepipes is termed as Hot Finish Seamless or cold drawn seamless as the term implies.