Compression method, rotating torque method, delivery method is rubber products and plastic three test methods.Compression method is simple, accurate test, we often used is William type and varley type method, but a certain distance with the actual production, after all of the sample by the shear rate is low.
1, varley type method, under the condition of the temperature, time, and conforms to the same, according to the variation of plastic rubber mixing sample thickness to represent the plasticity.Determination will be about three ? thick film, when cutting a diameter of about 13 ?, constant volume was 0.4 + / - 0.04 cm3 sample, put to rapid tester, test the temperature of 100 soil 1 ?.The sample and then quickly closed pressure plate, preloading to l ?, preheated after 15 s, 10 kg load, and the second 15 s, the reading of the thickness gauge instructions for plastic rubber mixing plasticity, namely the whole operation time is only 30 s.Regulation 0.01 ? said 1 unit of plasticity, such as the thickness gauge measured 0.46 ? specimen thickness, it indicates that the varley plasticity is 46, varley type numerical value, the greater the plasticity is smaller.                                                          
2, William type fast plasticity, the basic principle of the measurement and varley's method is the same, under constant temperature, constant load, the change in the height of the sample after a certain time to plasticity.To determine the original high h0, room temperature under 70 soil 1 ? temperature, preheat first 3 min, then under this temperature, the 5 kg load between two parallel plates, compression after 3 min height determination of h1, remove load, remove the specimen, on restoring 3 min at room temperature, measure the height of the h2 after recovery.
3, delivery method, sample consumption, testing time is long, in industrial production application is less, commonly used in scientific research.It is every lmin ml of plasticity number or quality g said.The faster the numerical values, the greater the pressure out.The greater the plasticity of the rubber.The process is similar to the working condition of the mouth the extruder, it can more accurately reflect the rheological properties of the rubber.
This is one small make up the summary about the rubber o-rings, rubber seal, rubber seals and other rubber products of plastic testing methods, deficiencies please understanding.