What is ISO 8840 about?
ISO 8840 specifies three methods for the determination of the bulk density of granular refractory materials (grain density) having a grain size larger than 2 millimeters.
The methods are:
- Mercury method with vacuum
- Arrested water absorption method
- Vacuum method with spin dryer option according to ISO 5017
Note: Depending on the nature of the material tested, the three methods can give different results. Any statement of the value of a bulk density can therefore be accompanied by an indication of the method used or to be used in case of a dispute.
Who is ISO 8840 for?
ISO 8840 on determination of bulk density of granular refractory materials is relevant to:
- Refractory products manufacturers
- Industries including, but not limited to iron and steel, petrochemical, cement, ceramics etc
- Mechanical engineers
- Metallurgists
Why should you use ISO 8840?
A refractory material or refractory is a material that is resistant to decomposition by heat, pressure, or chemical attack, and retains strength and form at high temperatures. Refractory materials are used in furnaces, kilns, incinerators, and reactors. The apparent bulk density is a property of the powders, granulated and other divided solids, used for the mineral components and chemical substances. It is defined as the mass of numerous particles of the substantial divided by the total volume they inhabit.
Determination of bulk density of granular materials is very important as it is a means to assess the strength of the refractory material. With the help of ISO 8840, assessment of bulk density of granular refractory materials could ensure its optimal functionality in applications where thermomechanical properties are vital. Higher the bulk density, better is the volume stability, heat capacity and resistance to slag penetration and abrasion.
What’s changed since the last update?
This second edition of BS ISO 8840:2021 replaces the first edition ISO 8840:1987, which has been technically revised. The main change as compared to ISO 8840:1987 is:
- A new method according to ISO 5017 has been added. It is identical to the method given in EN 993‑18 with a suggested improvement to avoid the most influencing factor of the operator