管螺紋接頭壓力容器之應力分析

Stress Analysis of Pressure Vessels with Threaded Joint

曾俊偉(Jyun-Wei Zang)

指導教授 ： 陳政順

國立臺北科技大學/機電學院/製造科技研究所/碩士(2010年)

摘要

本文探討1 1/4PT，鋁合金 6061-T6 之推拔管螺紋接合之圓筒壓力容器，於承受內壓負荷時之有效應力分析及接觸元件應力集中與損壞分析等問題，利用商用有限元素分析軟體進行模擬螺紋牙及元件其他部位的應力行為，以了解螺紋連接處所產生最大應力集中及接觸應力的情形。本研究個案中在25 MPa內壓下，分析結果顯示應力集中因子介於2.97~3.95之間。而在承受41.37 MPa內壓時，螺紋連接處兩端之牙根處有最大等效應力發生也是螺牙破壞的關鍵位置，此位置也是破壞實驗產生斷裂的位置。 最後再進行探討在相同內、外徑及壁厚條件之下，不同螺紋種類之螺紋接頭壓力容器之連接強度分析；結果顯示，在相同大小之內壓力作用力下，推拔管螺紋接頭壓力容器可以承受最大之內壓負荷 ，而鋸齒形螺紋接頭壓力容器則為最小。

關鍵字

壓力容器 ； 管螺紋接頭 ； 有限元素分析

並列摘要

This study investigates on the stress–strain distribution, stress concentration factors, and fracture behavior of an Al 6061-T6, 1 1/4PT threaded pressure vessel under pre-load and internal pressure. The commercial finite element software, ANSYS, is used to simulate the stress distribution of threaded joint, and the stress concentration factor (SCF) and contact stress around the threaded portion are calculated and analyzed. The results show that the stress concentration factors for threaded joint are between 2.97 to 3.95 under the internal pressure of 25MPa. And the higher equivalent stresses are generated around the ends of the mating threads which seems to be the critical locations for failure. This had been validated by experimental test. Finally, the connection strength of different types of threaded joint of pressure vessels is also studied and the results reveal that the taper pipe threads have the highest load capacity compared to others under the same loading conditions.

並列關鍵字

Pressure Vessel ； Threaded Joint ； Finite Element Method

參考文獻

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