[en] The procedure was developed for electroslag welding of two-layer 12KhM-08Kh18N10T steel, 80 mm thick, without removing the cladding layer. The mechanical properties of welds after various kinds of heat treatment were studied. It was established that the mechanical properties of welds which were tempered met the standing specifications. Forming devices were developed to protect the cladding layer against melting. The results were used in developing a procedure for electroslag welding of chemical reactor bottoms. The industrial introduction of the procedure yielded an economic effect of 20000 roubles through replacement of manual welding by electroslag one