| 摘要 |
FIELD: heat supply systems. ^ SUBSTANCE: proposed steam boiler has cylindrical casing, heating surface in form of screw coil installed in furnace concentrically relative to casing and separator connected with coil and furnished with branch pipes to let in and out of steam-water mixture and water. Furnace is furnished additionally with heating surface in form of vertical gas-tube unit with fire tubes connected with separator and forming, together with separator, additional water circulation circuit. One part of housing of gas-tube unit is located in boiler furnace, and other part projects beyond the limits of furnace by (Lf) found from following equation: Lf=Lt[(Tinalphah-Tftalphaft)/(Tinalphah-Toutalphah)] where Lt is total length of housing of gas-tube unit, mm; Tout is temperature of wall of gas-tube unit housing part projecting beyond the limits of boiler furnace, °C; Tin is temperature of wall of part of housing arranged in boiler furnace, °C. Tft temperature of wall of fire tubes, °C; alphah alphaft are linear expansion coefficients of material of gas-tube unit housing and fire tubes, respectively, 1/°C. ^ EFFECT: improved reliability of boiler. ^ 1 dwg |
