Materials, Methods & Technologies, Volume 3, 2009

Streszczenie: Enlargening volumes of industrial production and requirements after more bold circumstances of work - not only in the engineering, different kind of transport, but also in other spheres of production always more frequently begin to use the devices of the compressed air. One of them is screw type pumps. Screw type compressors is simple design rotor machines of the positive moving, what can operate with greater efficiency on high speeds of rotary rate, and operate in the spacious range of pressures. In foundation of structure of compressor there are two shafts with specially created in the type of spiral for the shafts. The rotors of pump are inferior to influencing of variable forces, which produce the compressed gases and forces of inertia, and moments of rotary also. Requirements for these rotors comparing high, they should be made from quality materials, which provide excellent characteristics in statistical and dynamic pointers of mechanical resistance – strength, hardness, plasticity, should be with good corrosion, warm and wear resistance. In foundation of article main attention is paid on making of new or improved technologies, to perfect properties of steels of lower quality, which will assure material, which always technological and mechanical dignities would characterize, adjusted for the production of rotors. More detailed this work analyzes changes of steels technological, mechanical properties, using thermal processing methods of strengthening, their advantages and failings. Knowing that many elements, as example, carbon, nitrogen and others, improves technological and mechanical properties of overlayer of material, in motion of work shallow analyzes thermal chemical influence also. Advantages of more frequently used technologies and failings are also analyzed in that work. The rotors of screw type compressors are one of the most responsible details of compressor, and productivity of action depends from them. At the end of article conclusion gives various advices for the improvement of surface of rotors.