Water Absorbtion Water absorption is of particular interest in the ceramic packing as it indicates the degree of firing and vitreousity of the packing material. Resistance to Acid Acid resistance indicates the resistance or the solubility of the material subjected to the attack of concentrated acid. Crushing Strength Crushing strength is the load required to break the packing. In Ceramic rings it is applied diametrically and strength is usually expressed in Kg/linear Cm., while in case of saddles and other items the total load required in Kg. to break the piece is expressed as crushing strength. Chemical Analysis In packing materials, the chemical analysis is only indicated since the versatility of the packing depends on the performance of the product. More Links : Raw Material Test | Inprocess Test | Firing Controls | Final Product Tests | Quality Norms Raw Material Test  Physical Inspection for colour and texture  Particle Size  Chemical analysis. Inprocess Test  Particle size by sieve analysis  Density of slip • Filter cake moisture content  Extruded blank moisture after drying to leather hard condition  Random tests for dimensions  Visual Inspections  Pre Kiln moisture content tests Firing Controls Firing control by automated combustion control systems(Air Fuel ratio, Temperature firing curve) Steady pre heating to avoid stresses on the ware Long soaking to achieve 100% penetration of heat through out the wall thickness to facilitate proper VITRIFICATION Rapid cooling upto 700 degree Celsius Slow cooling from 700 to 600 degree Celsius (to facilitate quartz inversion volume change) Bringing down to room temperature at a steady rate Final Product Tests Dimensional Checks Weight Water absorption Resistance to Acids and Alkalis Crushing strengths Tests conducted as per ASTM 279C, DIN and Customers specifications Quality Norms Quality norms are maintained as per ASTM/DIN/As per Customers specifications