The invention concerns an oxyacetylene cutting apparatus comprising a support element (10) produced from a stainless steel block which cannot be deformed, a heating element (20) permanently fixed against a bottom surface (19) of the support element (10), which heating element is produced from a massive copper block wherein are provided passages for gas fluids and the cooling fluid which communicate directly with the support element (10) corresponding conduits. At least one nozzle (30) is precisely positioned in two coaxial bores (31, 32) provided in the support element (10) and the heating element (20) respectively, the nozzle being connected to a conduit (14.6) supplying oxygen for cutting. A retaining element (40) is preferably used to enhance the precise positioning of the nozzle (30).