吊鉤應力分析

Stress Analysis of Hooks

本論文討論危險性機械元件－吊鉤在標準靜荷重時，以有限元素法及實驗應力分析方法估量其最大應力，目前大多數國家的吊鉤安全標準是以此最大應力為參考。傳統上的分析大皆將吊鉤看成一直樑或曲樑，應用樑的公式來估算吊鉤承受負荷時的最大應力，此最大應力應小於吊鉤材料之抗拉強度除以相當的安全係數。本研究是以二維及三維有限元素方法、應變規量測及光彈量測來分析吊鉤受負荷時的靜態最大應力。其分析結果，有限元素分析之結果與實驗量測值極為接近，然傳統的計算值與實驗應力量測值相差甚大，其中傳統曲樑法計算值又較直樑法計算接近實驗量測值。

The paper deals with the maximum stress evaluation of a hook under standard static load by finite element analysis (FEA) and experimental stress analysis methods, most of the safety standards are based on this maximum stress. In the past, the hooks were modeled either as straight or curved beams, formulas of beams were utilized to evaluate the maximum stress. This maximum stress should be less than the tensile stress of the hook material divided by the specified safety factor. Two-dimemsional and three-dimensional finite element analysis as well as strain gage and photoelastic tests were conducted to measure the maximum stress of the hook under static load. The comparison between computational and experimental results shows the analysis by FEA is close to the experimental values. While the hook modeled by curved beam is better than that by straight beam.