抄録
In order to establish a proper method of testing the hardness of plastic pipes, which is the objective of our study, various kinds of experiments were performed on plastic pipes most commonly used in industries and other fields for transporting fluids. The hardness measurement of plastic pipes depends on the following factors: (1) shape of measuring face, (2) testing conditions and measuring method, (3) conditions of pipe samples, and (4) deflection of pipes.
Since the results of hardness tests are useful not only for the quality control of plastic pipes but also for the convenience of commercial transactions, the machines to be used for testing their hardness must be those acceptable in a wide area. The principal characteristics required for the hardness testing of plastic pipes are: (1) reduction of uncertainty in the measured values, which is particularly important for maker-commercial transactions, and (2) simplicity of determining mechanical properties at high or low temperatures over a long period of time, which is important for the user.
