Reducing the ratio of the ventilation section of the grate means increasing the resistance loss of the grate, increasing the airflow velocity through the grate, and reducing the temperature of the grate itself and improving the working conditions. General ventilation section ratio is not more than 2%2. Cooling degree of grate The degree of cooling of the grate (ω) is an indicator of the reliability of the grate, which is equal to the ratio of the total area of the fins (SFin) of all the grate slabs to the total area of the grate (SGrate):