Sand moulds are supposed to take up all the load that is inflicted upon it. The load may be structural as applied by the mould material. Or it may also be due to the weight of the casting material when it is poured in to the mould. Although the moulds are designed with utmost care, taking established material property data and practices into consideration, it may not always be possible to obtain the desired characteristics due to the difference in processing the materials. Hence at the end of a design, it is customary to prepare a test specimen and obtain the property specific to that design or the batch.
Compression test is carried out on symmetrical specimen which may either be cylindrical or cubical/rectangular. The size of the specimen is taken as per the prevailing standard usually accepted in the locality. There are some universally accepted test standards as laid down by ISO and BIS, too. These standards clearly specify the test method and specimen shape or dimensions to be used in the test. They also make the data acquisition and reporting method universal so that reports from different test labs or places can be compared and conclusions can be arrived upon with accuracy.
Sengerandu's Tutorials 