Rubber ball test method for density of the conversion of the water volume of Archimedes' principle, carry on the test according to the TS16949, ISO14000 operation specification, densitometer using hundreds of thousands of 0.00001g/cm3 for the high precision rubber density meter, density meter mainly balance, measurement units, wind shield group into. Measurement of the number of test samples: 10mm rubber ball 10pcs. Measurement of liquids using pure water, the proportion is 1g1g/cm3.: first by plotting meter to measure the rubber ball in the air of the weight, then put the rubber ball into in the water and measuring the water weight, the calculation formula P =Wa P in the water / Wa-Wb). By calculating can be rubber ball density and volume calculation formula are obtained.