Sökning: "rolling contact fatigue"
Visar resultat 1 - 5 av 60 avhandlingar innehållade orden rolling contact fatigue.
Sammanfattning : Rolling contact fatigue (RCF) is a very common and costly damage mechanism for rails and wheels. This thesis investigates the influence of combined thermal and mechanical loading on RCF of railway wheels on the basis of numerical predictions. LÄS MER
Sammanfattning : Rolling contact fatigue is a damage process that may arise in mechanical applications with repeated rolling contacts. Some examples are: gears; cams; bearings; rail/wheel contacts. The resulting damage is often visible with the naked eye as millimeter sized surface craters. LÄS MER
Sammanfattning : Increased traffic density and the heavier axle loads of modern trains have led to severe problems with rolling contact fatigue (RCF) which cause initiation of surface cracks in railheads. In this thesis, a specific type of surface crack, the head check, is studied numerically with emphasis on fatigue crack initiation. LÄS MER
4. Squat defects and rolling contact fatigue clusters - Numerical investigations of rail and wheel deterioration mechanisms
Sammanfattning : Squat defects, a type of localised rolling contact fatigue damage appearing on rail surfaces with rail break as an ultimate consequence, have concerned infrastructure managers for the last couple of decades. In recent years similar types of defects—so-called studs—that are visually resembling squats, have started to appear. LÄS MER
Sammanfattning : Railway rails are today often continuously welded. This type of joint generally requires less maintenance than is needed for the bolted joints. It has also reduced wheel damage and made the ride more comfortable. However, these joints are subject to damage. LÄS MER