Download: Quality-Assurance.pdfTesting PhilosophyTo supervise and maintain the quality standards laid down, various checks are carried out on all components of the turbines.Testing MaterialsThe materials used for the different components of the turbine have their chemical composition, their strength and physical properties checked before being processed. With this objective the following are carried out, depending on requirements: 1.Chemical analysis 2.Metallurgical investigations (structure) 3.Non destructive tests, such as ultrasonic, X-ray or magnetic particles tests 4.Tests on specimens of the material, such as tensile test, notch impact test and hardness testChecks during ManufactureTheir purpose is to keep a continual check on the turbine components with regard to geometry and finish in comparison with specified data.Assembly ChecksThese are carried out to ensure that the clearances necessary for correct operation of the turbine are observed, and that all sub assemblies and units function properly.Works TestingTests are performed in the factory, with steam, to check the components on which the reliability of the turbine depends. The bladed rotors are statically and dynamically balanced and then tested at 10% over speed in the turbine. *Equipment for the control of the turbine are mounted and then checked to make sure they function correctly and then set to the values required for operation.Works AssemblyAll turbines are completely assembled in the factory, following which the clearances between fixed and moving parts, necessary for correct operation, are checked. Turbines dispatched as packaged units are cleaned after testing, coated with a preservative medium and then assembled in a transportable state. As a result, erection on site is confined to a few minor manipulations and to connecting up the external piping.