【毕设用---外文翻译来源】ANSYS英文论文 (124).pdf

Analysis for Distortion Control C Machine
Rajan Khakhar
M. T. Rane
R. V. Kulkarni
Larsen & Toubro Limited, Mumbai, India
Abstract
The Machine Shop of Larsen & Toubro Limited has C controlled, vertical spindle machining center
for high accuracy machining. It is a dual spindle machine, which is presently used for deep-hole drilling
operation.
The gantry of this machine was reported to undergo lateral distortions (200-400 microns) at slave end with
respect to time. For a special high precision job, machining with this distortions of the machine was not
meeting the tight tolerance requirements.
The reasons for these distortions were investigated and measurements were carried out. The effects of
variation in environmental conditions on machine distortions were analyzed by finite element method using
ANSYS package. The trend of the analysis results closely matched with the actual measurements. This
provided the clues in providing the proper solution. After implementation of the solution experiments were
carried out to check the effectiveness of the solution. The measurements indicated that the distortions were
controlled and requirement of machining accuracy established.
Introduction
The Machine Shop of L&T has C controlled, dual spindle machining center for deep-hole drilling
application.
The structure of the machine is of gantry type. The sketch of the gantry is shown in Figure 1. The gantry is
mounted on guideways through bearings. For transverse motion along the guideways, a drive is provided
on one side of the gantry. This end is called the master end & the other end is called the slave end. The
motion of the gantry in perpendicular direction to guideways is restricted by bearing arrangements at
master end. At the slave end, the gantry is resting on the guide ways and all other motions are free.
Figure 1. Sketch showing overall view of Machine Structure
The gantry of the machine was reported to undergo late