It is possible to examine steel pipes under two headings; these are welded and seamless (drawn) pipes. Welded Pipes: Semi-finished products in the form of coils are first sized according to the desired pipe size. Then, the flat sheet is shaped step by step, first half a month and then a full circle. After the circle is completed, welding is performed similar to the movement of the sewing machine, and joining is performed from one end to the other. Pressure values ​​are low as welding is used in its production. The purpose of use of welded pipes is mostly used in low pressure lines and for decorative purposes. Seamless (Drawn) Pipes: Produced by rolling the kiln-dried billet. At high rolling speed and pressure, the configuration creates pressure in the center of the slab and pierces with a pointed rod to form the tube sleeve. This sleeve is then extended to a multiple rolling stand with a mandrel or a long bar and placed inside the pipe to achieve the desired wall thickness and diameter range, completing its production. It is more resistant to pressure because it is poured in one piece and does not contain seams. It is especially preferred where the pressure is high.