螺紋結合件之螺紋應力均化分析

Equalization Analysis of Thread Stresses of Threaded Fastener

劉正欽(Jeng-Chin Liu)

指導教授 ： 蔡定江

國立臺北科技大學/機電學院/製造科技研究所/碩士(2011年)

摘要

本文針對受軸向負載螺紋接合，由於負載及邊界條件的不同，會有應力不均或螺紋應力高度集中於某幾牙的問題，造成螺紋局部損壞而降低螺紋件的負載容量，根據材料勁力度變形與受力理論關係，適當的調整螺紋牙間隙，使用ANSYS/LS-DYNA探查螺紋接觸部位的牙根應力分佈，然後建立應力均化指標作為螺紋應力分佈的參考依據。由分析結果得出，施力與支撐為不同端時，螺帽節距不變情況下，將螺帽牙由中間往兩邊給予間隙，應力均化指標會有下降的效果，施力與支撐為同端時，越靠近邊界條件端的螺帽牙間隙調整要越大，遠離的要越小，螺紋接觸應力就會有均勻分佈在各牙的現象。

關鍵字

螺紋 ； LS DYNA ； 應力分析

並列摘要

In this study, the joint is presented for the screw under axial load. As the load and different boundary conditions, the screw will have non-uniform stress or stress concentration problem of a particular few teeth. Therefore, the screw will have local damage and be reduced load capacity. According to material deformation and stress theory, the study appropriate modify the gap of screw. The stress distribution of the contact part of the thread root was analyzed by ANSYS/LS-DYNA. Finally, the balance indicators of stress have been established as the reference of screw stress distribution. The results showed that the balance indicators of stress will decrease when the force and support in a different face and the nut’s pitch is constant, because nut have clearance. Nut tooth that near the end of force and support increase the gap when the force and support on the same side. Then the screw’s contact stress will be evenly distributed in the each tooth.

並列關鍵字

Screw ； LS DYNA ； Stress Analysis

參考文獻

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[10] 葉輪編著，機件原理總複習，台北：科友圖書股份有限公司，2004。

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