From steel strip to tube



The raw material for JANSEN precision steel tubes is hot-or cold-rolled steel strip, made from plain or low alloy carbon steels. Hot strip is first pickled in acid to get rid of mill scale.



So-called longitudinal seam tubes are produced as follows: after passing through profile rolls, sections of strip steel are shaped on the welding machine into tubes or profiles with a longitudinal slot. A high-frequency system heats the strip edges to welding temperature inductively, i.e. without contact, in the shortest possible time, after which they are pressed together by an edging roll (pressure welding). The pressure welding process uses no extraneous materials. For this reason the weld seam has the same chemical composition as the base material. The weld burr produced during edging is removed - always on the tube exterior, and on the tube interior too if the intended application demands it. A flying saw cuts the endless tube into the desired lengths.

The welded and specifically-sized precision steel tube leaves the welding machine with its final cross section, namely:

  • round, as per DIN 2394
  • square and rectangular,
    as per DIN 2395
  • flat oval, oval, half-round, or special-profile steel tubing and other special shapes to customer requirements.