[en] A method is proposed to test for tendency of cracking thick-walled welded joints on model samples of low-alloyed steels contained in blocks of austenitic steel. Testing was carried out under a continuously increasing deformation, and change in temperature simulating the thermal cycle of a welding process. Conditions underlying the formation of cracks in simulated weld zone during heat treatment were studied by considering chromium-molybdenum-vanadium steels. Temperature dependences were obtained for the variation of stresses in the course of heating