Line pipes for the transport of liquids, gases and bulk materials are the most widespread assortment of pipes. These are pipes that work under pressure. The value of this pressure varies depending on the specific application (low pressure, medium pressure and high pressure pipes). Also, the connections of the service pipes can be different, each having many variations (e.g., connections by means of threaded pipe fittings, direct welding of pipes together, flange connections). The constructed pipelines are equipped with various types of fittings, such as valves, gate valves, taps, designed to change the amount of medium, pressure or temperature.