| Autor: |
A. K. Ahirwar, V. Gopika, P. K. Ramteke, J. Chattopadhyay, N. B. Shrestha |
| Rok vydání: |
2019 |
| Předmět: |
|
| Zdroj: |
Reliability, Safety and Hazard Assessment for Risk-Based Technologies ISBN: 9789811390074 |
| DOI: |
10.1007/978-981-13-9008-1_27 |
| Popis: |
Nuclear power plants (NPPs) contain myriads of electrical cables of all sizes, voltage ratings and lengths delivering electrical power to much vital, as well as non-vital equipment. These cables are insulated with some form of polymeric insulation. These insulating materials will gradually age from exposure to heat, radiation, moisture and chemicals. Usually, the evidence for satisfactory performance over a period of designed life is provided by the results of the qualification tests, simulating operational ageing and the postulated design basis accident. Experience has shown that the failure of nuclear cables is primarily due to the hardening and embrittlement of the insulation resulting in the formation of micro cracks, a loss of dielectric strength and high leakage currents. Percentage elongations-at-break (E-at-B) are derived from measurements by tensile tests on cable insulation materials to establish qualified life. Monitoring cable degradation by measuring E-at-B is in many cases not feasible as it requires the periodic removal of cable samples from the field for destructive testing. Condition monitoring (CM) is an effective technique to assess the functional capability/operational readiness of cables during the plant operation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
