1. What mechanical tests are performed on boiler tube materials?
Tensile testing at room and elevated temperatures. Hardness surveys (Brinell, Rockwell). Impact testing (Charpy V-notch). Creep and stress rupture testing. Bend tests for ductility verification.
2. How is chemical composition verified?
Optical emission spectrometry (OES). X-ray fluorescence (XRF) analysis. Combustion methods for carbon/sulfur. Wet chemical techniques for specific elements. Often performed at multiple production stages.
3. What microstructural examinations are important?
Grain size determination. Inclusion content and distribution. Phase identification and morphology. Carbide precipitation analysis. Heat treatment verification.
4. How are corrosion resistance tests conducted?
Salt spray testing for coatings. Electrochemical methods for alloys. High-temperature oxidation tests. Stress corrosion cracking evaluations. Custom tests simulating service conditions.
5. What are the sampling requirements for testing?
Representative locations in raw material. Weld and HAZ regions for assemblies. Both longitudinal and transverse orientations. Multiple samples for statistical validity. Proper identification and chain of custody.
