MEASURING METHOD FOR INSULATION RESISTANCE OF INSULATED JOINT FOR BURIED PIPE LINE

摘要

PURPOSE:To accurately evaluate the performance of an insulated joint without being influenced by metal pipes by constituting a bridge circuit with 1st, 2nd metal pipes, variable resistor, grounding pole and reference electrode, and adjusting this variable resistor. CONSTITUTION:The insulated joint 3 is connected between the 1st and 2nd metal pipes 1, 2. One terminal of the variable resistor 4 is connected to the 1st metal pipe 1, and another terminal is connected to the grounding pole 5, then an electrode 6 is connected between the 2nd metal pipe 2 and the grounding pole 5. Further, between the reference electrode 8 inserted into the earth and each of the 1st metal pipe, 2nd metal pipe and the grounding pole 5, potentiometers 9, 11, 10 are connected respectively, thereby the bridge circuit is constituted. With this arrangement, the performance of the insulated joint can be accurately evaluated without being influenced by the metal pipes by means of measuring the insulation resistance of the insulated joint 3 from a balancing condition obtained by adjusting the variable resistor 4.