Abstract :
The large visual inspection and nondestructive testing programmes carried out as part of major power plant overhauls normally identify many features which require to be accurately recorded or further examined to determine their nature and severity. In many cases, due to the shape of the components concerned and/or access, direct visual and microscopic examination may not be possible and indirect examination of a replica made of the feature or area concerned may be the preferred method of examination. The author describes how, in response to this requirement within the power generation industry, three main replication methods have been developed: bulk replication; macro replication; and micro replication