The analysis of the operation of a roller feed-through furnace with radiation tubes and a protective atmosphere designed for heat treatment of boiler pipes is carried out, and two processes are simultaneously combined: normalization and tempering. It is established that a long furnace length (of the order of 62 m) makes it difficult to obtain the necessary cleanliness of the pipe surface. Industrial investigations were carried out in order to assess the effect of the operating fan installed on the right side of the furnace on the heat treatment regime and the quality of the pipe surface. Measurements of the static gas pressure along the length and width of the furnace are performed and the content in the protective gas O2 and CO2 is determined. It is established that the static pressure at the surface of the furnace walls decreases, leading to a reduction in the amount of air sucking into the working space. A new design of roller sealing has been developed, the use of which allowed increasing the gas density of the furnace working space, the static pressure, reducing the cost of expensive protective gas and improving the surface quality of the boiler pipes.