BS ISO 7992:2015 pdf free
BS ISO 7992:2015 pdf free.Iron ores for blast furnace feedstocks – Determination of reduction under load
Reduction tube, with a double wall made of non-scaling, heat-resistant metal to withstand temperatures higher than 1 050 °C and resistant to deformation. The internal diameter of the inner reduction tube shall be 125 mm±1 mm. A removable perforated plate, made of non-scaling, heat-resistant metal to withstand temperatures higher than 1 050 °C, shall be mounted in the reduction tube to support the test portion and to ensure uniform gas flow through it. The perforated plate shall be 10 mm thick, with a diameter 1 mm less than the internal diameter of the tube. The holes in the plate shall be 3 mm to 4 mm in diameter, at a pitch centre distance of 5 mm to 6 mm. The internal diameter of the outer reduction tube shall be enough to allow gas flow preheating before entering the inner reduction tube. In order to achieve a more uniform gas flow, place a double-layer bed of porcelain balls (6.6) in the reduction tube (6.2) on the perforated plate and level its surface. Measure the height of the top surface of the porcelain layer.
Take, at random, another test portion prepared in 5.2 and record its mass (mo). Place it on the bed of porcelain balls and level its surface.
Place a further double layer of the porcelain balls upon the test portion and level its surface. Measure the height of the top surface of this porcelain layer.
Close the top of the reduction tube by connecting the heating assembly containing the loading device (6.3) to the reduction tube. Insert the reduction tube assembly into the furnace (6.7) and suspend it centrally from the balance (6.8), ensuring that there is no contact with the furnace wall or heating elements.
Connect the thermocouple, ensuring that its tip is at the central position, as shown in Figure 2. Connect the measurement devices for the differential pressure (6.4) and for the change in the height of the test bed (6.5).
Connect the gas-supply system (6.9), the discharge line and the compressed air to the loading device. Apply a load of 50 kPa±2 kPa.BS ISO 7992 pdf free download.