Fans of the series for conveying non-corrosive, not spontaneous combustion, the temperature does not exceed 1100 ℃ high-temperature gas, the medium contained in the dust and hard particles is not greater than 150mg / m in the form of one, fans of the series as a single inhalation. 2. Fans of the series can be made right-handed and left-handed in two forms, one end face from the motor, the impeller rotates clockwise rotation of the fan, said the right to the "right" means; counter-clockwise rotation of said left fans with " left ". 3, the fan casing exit angle export position, said, "left" and "right" can be made of 0 °, 45 °, 90 °, 135 °, 180 °, 225 ° total of six kinds of angles.