2014 International Conference on Mechanism Science and Control Engineering (MSCE 2014)
ISBN: 978-1-60595-183-6
The Study for the Impacts on the Position of Heavy Gantry Machine
Tool Tip of Uneven Foundation Settlement
Jian-Hua WANG
1,a
, Ke ZHANG
1,b,*
, Zhi-Feng LIU
1,c
, Yang TIAN
1,d
1
College of Mechanical Engineering and Applied Electronics Technology, Beijing University of
Technology, Beijing, 100124 China
a
wjh@bjut.edu.cn,
b
zkbjut@163.com,
c
lzf@bjut.edu.cn,
d
remlove@163.com
*
Corresponding author
Keyword: Uneven foundation settlement, Heavy gantry machine, Precision, Model
Abstract. The study for the impacts on the machining accuracy of heavy gantry machine of uneven
foundation settlement, there is a heavy gantry machine for study. Assuming the machine base
produce two differential settlement because of the uneven foundation settlement, the whole machine
tool structure deformation caused by the differential settlement let tool tip have an offset position
and angle that affect the machining accuracy. This paper established the model to study the impacts
on the machining accuracy of heavy gantry machine of uneven foundation settlement on the basis of
the overall model of the machine to simplify, can provide theoretical and technical guidance for the
design or the structural optimization or error compensation of heavy gantry machine.
Introduction
In recent years, with the implementation of a number of key special programs of the State
Council, the government continued to increase the input in aerospace, nuclear power wind power,
railway locomotives, marine vessels, transportation and other key project [1]. The key components
of engineering equipment are large-size, heavy-tonnage, high-precision parts. To undertake the
processing, of typical parts like this, we must develop a high level of large, heavy, super heavy-duty
CNC machine tools [2, 3]. With the demanding of machining accuracy increasing, modeling
accurate machining accuracy is critical, especially for heavy heavy-duty machine tools, its own
weight, high load strength and deformation of large parts, more demanding of the carrying capacity,
studying the impacts on the precision of heavy-duty CNC machine tools is very meaningful[4, 5].
At present, the rules that uneven foundation settlem
ent impacts on the Superstructure has been a
lot of research. Chang Liu assumed the foundation to be elastic support, carried on a overall
analysis of the superstructure and foundation [6].Jun Dong did a nonlinear analysis of the damaged
upper steel that uneven foundation settlement caused, that could provide details of structural
damage process and the change of reinforcement [7]. Jian-yong Yue proposed a simplified
three-dimensional finite element analysis model, simulated the complex interactions between soil
and pile cap [8]. Qiang Jia used the finite element program to analyze the rules that the uneven
foundation settlement of a Three-tier framework impacts on the internal forces of superstructure [9].
Machine Uneven Subsidence Model
According to material mechanics, we can know the deflection curve differential equations:
2
2
ω
′′
= =
d M
ω θ
= = =
′
∫
M
ω
∫∫
( )
(1)
The simplified model shown in Fig.1: