>>We have a requirement of copying PRD client to prepare QA New client. The size of PRD client is around 1 TB<<
If the size if 1 TB why are you doing a client copy? For such systems a backup and restore based system copy would be the right approach. The export and import time depends on the hardware resources and there is no way others can assist you without knowing what the hardware setup looks like. Instead of wasting time by frequently checking the export and import progress do a system copy using the backup and restore option.