In welding elements of the supporting structure of the means of transport, attention is paid to the high strength and good plastic properties of the welded joint. In the construction of transport means, DOCOL 1200M  steel from the AHSS group is increasingly used due to their high tensile strength of steel at the level of 1200 MPa. The welds have much lower strength than the native material. In this paper, it was decided to check the weldability of  DOCOL 1200M steel with the use of micro-jet cooling