Article

Research on Impact Stress and Fatigue Simulation of a New Down-to-the-Hole Impactor Based on ANSYS

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Abstract

In the present work, a down-to-the-hole electric hammer driven by linear motor is reported for drilling engineering. It differs from the common hydraulic or pneumatic hammers in that it can be applied to some special occasions without circulating medium due to its independence of the drilling fluid. The impact stress caused by the reciprocating motion between stator and rotor and the fatigue damage in key components of linear motor are analyzed by the ANSYS Workbench software and 3D model. Based on simulation results, the hammer’s structure is optimized by using special sliding bearing, increasing the wall thickness of key and multilayer buffer gasket. Fatigue life and coefficient issues of the new structure are dramatically improved. However buffer gasket reduces the impactor’s energy, different bumper structure effect on life improving and energy loss have also been elaborated.

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... This paper is aimed to design the structure of electromagnetic hammer to meet drilling requirements, the pipe limitation and electric-mechanic requests. For example, the structure design must consider the request of structural strength and fatigue life [11]. ...
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  • PZ Xu
Dynamic analysis method of impact problem
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