To turbine body installers,ensuring ultimate efficiency of a unit is a problem to be highly concerned from start to finish of turbine installation.Although from design,manufacturer's level of processing,and constructor's level of installation,to plants' operation,etc.,there are many factors affecting turbine efficiency.Based on on-site installation experiences,good quality control on aspects,such as casing positioningmode,equipment and part inspection,flow gap adjustment,steam inlet sealing ring inspection,and connecting large size pipe to casing,etc.,can contribute to turbine efficiency improvement.