ISO 1927-8-2012 pdf free download

ISO 1927-8-2012 pdf free download.Monolithic (unshaped) refractory products — Part 8:Determination of complementary properties
Produits réfractaires monolithiques (non faconnés) — Pa rtie 8: Déterm in a tion des caractéristiq ues complémentaires.
6.1 Principle
This determination may be carried out on fired or unfired, dried test pieces in accordance with Iso 8894-1 (hot wire, cross array) or with ISO 8894-2 (hot wire, parallel).
For both fired and unfired, dried test pieces, variation in thermal conductivity can occur due to time-dependent mineralogical and microstructural changes if the test piece has not been prefired to a temperature equal to or higher than the measurement temperature.
It is therefore necessary to take special care to ensure that equilibrium is attained when testing such test pieces. This can entail holding the test furnace at the measurement temperature for prolonged periods.
6.2 Test pieces
Test pieces shall be used corresponding to shape A as defined in ISO 1927-5.
For fired test pieces, the firing shall be carried out in accordance with ISO 1927-5 or as agreed
between the parties.
6.3 Procedure
Determine the thermal conductivity at each defined measurement temperature in accordance with ISO 8894-1 (hot wire, cross array) or ISO 8894-2 (hot wire, parallel). For unfired test pieces, the rate of rise of the test furnace shall be in accordance with that specified in ISO 1927-5 for the type of material under test.
In all cases where the test piece has been prefired, (either before or during the test) to a lower temperature than the measurement temperature, it may be necessary to maintain the furnace at this temperature for extended periods to attain equilibrium. In some cases, it is advisable to maintain the temperature overnight.
7 Determination of sulfuric acid resistance
7.1 Principle
Determination of sulfuric acid resistance consists of the chemical attack by sulfuric acid on test pieces crushed to a specific grain size.
7.2 Test pieces
Use shape A test pieces prepared in accordance with ISO 1927-5. stored and dried at 110 °C ± 5 °C for a
minimum of 24 h. Samples shall be taken out from test pieces in accordance with ISO 8890. Any pre-treatment of the test pieces shall be agreed between the parties and noted in the test report.ISO 1927-8-2012 pdf free download.