New Estimation Method of Fatigue Strength of Steel Weldments in Truck Frames
Takao NAGASE, Koji MATSUZAKI
The truck frames chiefly comprise 9mm thick rolled mild steels
and in their welded joints sometimes fatigue cracks occur on account
of inadequate fatigue design and poor weld quality. At present the
fatigue strength is estimated according to JIS E 4207 "General rules
for design of truck frames for railway rolling stock". This standard
assesses only the surface strength of welds, but does not the strength
of weld roots or the welds existing in the back surface of frames.
We have developed a new estimation method of the fatigue strength
supplementing JIS E 4207.