ref<\/sub>) × density and temperature corrections per the standard. Report the mean specific surface to the nearest 10 cm²\/g with bed porosity and temperature.<\/p>\nAcceptance Criteria<\/h2>\n
Ordinary Portland cement typically runs 300–400 m²\/kg (3000–4000 cm²\/g); rapid-hardening cements 400–550 m²\/kg. EN 197 sets no direct fineness limit \u2014 control is against the plant’s declared values \u2014 while low results correlate with slow early strength.<\/p>\n
Frequently Asked Questions<\/h2>\nWhy is bed porosity fixed at 0.500?<\/h3>\n
The Kozeny–Carman relation behind the method assumes a standard packing. Changing porosity changes airflow resistance independent of fineness, so the mass is always back-calculated to hit e = 0.500 exactly.<\/p>\n
How often must the apparatus be recalibrated?<\/h3>\n
Re-determine the cell constant with reference cement after any change of filter paper batch, manometer liquid, or cell components, and at least every six months in routine plant labs.<\/p>\n
Recommended Apparatus<\/h2>\n
NL Scientific manufactures the Blaine Air Permeability Apparatus<\/a> for this method. Browse the full Cement & Mortar Testing Equipment<\/a> range or request a quotation<\/a> from our engineers.<\/p>\n
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