PT Journal
AU Zivny, P
   Jansa, J
   Mekuta, M
   Lukasova, P
TI Crack Detection and Monitoring of their Growth in Critical Parts of Steam Pipeline by Electric Potential Drop Method
SO Manufacturing Technology Journal
PY 2025
BP 569
EP 574
VL 25
IS 4
DI 10.21062/mft.2025.046
DE Direct Current Potential Drop; NDT; pipeline
AB An innovative way of using DCPD (Direct Current Potential Drop) method for off-line and online monitoring of critical parts of energy equipment in operation is presented. There are only a few NDT methods that allow detection and monitoring of defect growth in components at high temperatures and pressures. Monitoring of steam pipes and critical pipeline components in operation has been carried out for several years with different results. a relatively new way of using the DCPD method outside the laboratory is described. The carried-out tests were intended to resemble operational loads as much as possible. Therefore, the tests were performed at a temperature of 20 °C and at an increased temperature of 550 °C. By gradually deepening the groove (slot) simulating the crack type defect in predefined steps, the growth of the defect was simulated up to the full wall thickness of the test sample. The primary evaluation was carried out from the absolute and relative values of measured resistance. The disadvantage of these values is their dependence on the temperature of the monitored area of the test sample and on possibly interfering DC voltages.
ER