This paper presents a procedure of single gear tooth analysis for early detection and diagnosis of gear faults.

By instrumental impact test and fracture analysis, the impact property of precipitatation-hardening stainless steel FV520(B) , aged at 350,420,470,520,560,600 and 630℃ was investigated.

Some in-site vibrating test and metal fracture analysis have been done to reveal that the crack of the U-shaped bolts is fatigue failure and some reference for designer is put forward.

On this paper, for the failure of a superheat steam pipe, via microscopic and macroscopic studies, we took the physical and chemical inspection, such as chemical composition, mechanical properties, metallographic structure, we also took the fracture analysis, then we got the failure reasons of the superheat steam pipe.

Failure Analysis of the Valve Body of the Multi-Functional Tri-Valve Set of Flow Transducer;