The Risø/HV Tube Inspection System is designed for fast automatic inspection of the dimensions of and defects in precision tubes. The system is based upon a rotating water chamber with eight ultrasonic transducers. Tube handling and evaluation of the results can be performed in various ways using different combinations of the modules in the system. This paper describes evaluation and development work on this system that has been carried out, based on practical experience with tube inspection. Also discussed is the influence of various modifications to the system on stability and accuracy during actual tube inspection, which was studied by repeated inspection of the same 17 tubes.