挖掘機吊掛能力之初步探討

A Preliminary Investigation for Lifting Capacity of Excavator

沈育霖(Yu-Lin Shen) ； 林俊宏(Jiun-Hung Lin) ； 康淵(Yuan Kang)

《勞動及職業安全衛生研究季刊》 23卷1期 (2015/03) Pp. 45-55

摘要

本文針對挖掘機執行吊掛作業之結構設計進行探討，先進國家已通過使用挖掘機進行吊掛作業之相關法規，而且挖掘機在營造工地用於物料吊運有其必要性及實用性。為了避免挖掘機發生翻覆或結構發生永久性的破壞，需從工程技術的觀點探討挖掘機實施吊掛作業之安全基準，本文以分析方法初步探討挖掘機吊掛作業之力學特性及構造強度，由挖掘機工作空間之機構分析，得到其大臂、小臂及鏟斗重心位置在不同姿態下之改變，進而求得其不同姿態下單位吊掛重量之內力及內力矩，以及翻覆力矩對應之臨界吊掛重量，將內力及內力矩代入大臂及小臂的有限元素模型進行應力分析，得到機器結構之材料強度所能承受的吊掛重量限界，本文未考慮風荷重、慣性力、衝擊負荷以及油壓缸能力，經此初步探討得到吊重能力在大部分區域內，機器傾覆先於結構破壞，但鄰近機器的某些區域傾覆比結構破壞有較大的吊掛能力，此外，本文也將分析結果與挖掘機製造商所提供之吊掛能力相互比較，試圖以本文模擬結果分析廠商的數據。

關鍵字

挖掘機 ； 吊掛能力 ； 應力分析 ； 穩定性

並列摘要

The paper investigates in stability and structure strength for excavator hanging work. Advanced countries have admitted the regulation to use excavators for hanging work. In practice, the excavator in the construction field is necessary for lifting materials to avoid excavator tip or permanent damage, it needs to investigate the safety of excavators implementation of hanging basis in the operation from the engineering view. The paper use analytical method to investigate the excavators mechanics and structure strength for hanging work. The change of gravity centers in various attitudes can be obtained from kinematic analysis, the internal forces and moment per unit lifting weight can be used to determine the corresponding critical capacity. Substituting internal forces and moment into the finite element model of joints for stress analysis gives stress distribution in components. The critical load for material strength of excavator structure can be obtained. Wind load, inertial force, impact, and hydraulic ability are not taken into consideration in this preliminary study. This paper results that the lifting capability due to stability is less than that due to structural strength. However, lifting ability due to tipping can be larger than that due to structural failure in some regions neighboring to machine and the excavator is particularly vulnerable to overturning in other regions. Also, this paper compares analytical results with capability provided by the manufacturer of excavators to analyze physical means of his data.

並列關鍵字

Excavator ； Lifting capability ； Stress analysis ； Stability

參考文獻

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Construction Plant-hire Association(2010).Mini Excavator Safety Instructions.London:The Association.

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