scholarly journals Assessment of the safety of use of portable machine tools

2018 ◽  
Vol 189 (3) ◽  
pp. 192-205
Author(s):  
Monika Nowak ◽  
Agnieszka Terelak-Tymczyna
Keyword(s):  
Machine Tool ◽  
Working Conditions ◽  
Machine Tools ◽  
Numerical Control ◽  
Milling Machine ◽  
Safety Issues ◽  
Large Size ◽  
Score Method ◽  
Characteristic Features ◽  
Risk Reducing

The article presents safety issues related to on-site machining with the use of portable machine tools. Their advantage is the possibility of machining elements at places in which they are used. This especially refers to large-size constructions, welded elements and any items whose disassembly is technically difficult. The authors present tasks performed by the operators of portable machining equipment, working conditions, construction and characteristic features of portable machine tools on the example of a portable boring machine, milling machine and flange facing machine. The presented characteristics can influence the safety of work with these machines. The information given in the article were used to asses risk at the position of a portable machine tool operator. The assessment was conducted using the Risk Score method taking into account four stages of using portable machine tools, i.e. transport, assembly/disassembly, machining and maintenance. The result of the conducted risk analysis is the proposal of possible risk reducing actions. Due to the specificity of the operation of portable machine tools which significantly impedes the development of a machine tool which would be safe in and of itself, the proposed actions refer mainly to organisational solutions. The work presents also the thesis that it is possible to decrease the risk at this position thanks to the use of numerical control in a portable machine tool. Such a solution may reduce exposure to some identified threats. The issue is presented on the example of a prototype of a portable flange facing machine developed in the Institute of Mechanical Technology ZUT in Szczecin.

Dynamics Analysis of Milling Machine Spindle

2013 ◽  
Vol 345 ◽  
pp. 137-140
Author(s):  
Yan Ru You ◽  
Hong Bin Liu ◽  
Li Gao
Keyword(s):  
Working Conditions ◽  
Machine Tools ◽  
Numerical Control ◽  
System Structure ◽  
Dynamics Analysis ◽  
Milling Machine ◽  
Processing Quality ◽  
Spindle System ◽  
Machine Spindle ◽  
Specific Working

The paper takes the numerical control milling machine xk8140 as the research object. The machine tools spindle system digital model is established in UG. The spindle systems natural frequency is obtained throng dynamics analysis of milling machine spindle under specific working conditions, as well as the relational of vibration and error in harmony response situation. In view of the result the rational appraisal to the spindle system structure rationality is made. Accordingly, the irrational causes removed, that noise increasing, processing quality reducing obviously and so on attribute to the irrational structure of the spindle system machine tools when the spindle rotational speed achieve 4000rpm or higher.

Research on Modal Analysis of Precision Micro Slitting Turn-Milling Machine Tool Based on Hammer Experimental Method

2019 ◽  
Vol 295 ◽  
pp. 67-72
Author(s):  
Zhong Peng Zheng ◽  
Xin Yang Jiang ◽  
Xin Jin
Keyword(s):  
Machine Tool ◽  
Modal Analysis ◽  
Experimental Method ◽  
Machine Tools ◽  
Processing Parameters ◽  
Milling Machine ◽  
Vibration Model ◽  
Vibration Modal ◽  
Turn Milling ◽  
Machine Structure

In order to improve the dynamic stability of precision micro slitting turn-milling machine tools, reduce or avoid the vibration problem during the cutting process, optimize the machine structure and processing parameters, the modal analysis of precision micro slitting turn-milling machine tool based on hammer experimental method was researched. In this paper, by analyzing the mechanism of precision micro slitting turn-milling machine tools, the multi degree-of-freedom mathematical vibration model of precision slitting turn-milling machine tools is constructed. The precision micro turn-milling machine tool is analyzed based on the hammer experiment analysis. The modal analysis obtained the first five natural frequencies and resonance speeds of the precision micro slitting turn-milling machine tool,including ST26, NN-25UB8K2 and NN-20UB87. The research results show that hammer experimental method can evaluate the vibration modal analysis of precision micro slitting turn-milling machine tools to some extent. The experimental modal analysis results guide and optimize the structural design and processing technology of precision micro slitting turn-milling machine tools.

Mathematical Approach for Geometric Error Modeling of Three Axis CNC Vertical Milling Machine

2016 ◽  
Vol 842 ◽  
pp. 303-310 ◽  
Author(s):  
Widyanti Kwintarini ◽  
Agung Wibowo ◽  
Yatna Yuwana Martawirya
Keyword(s):  
Machine Tool ◽  
Machine Tools ◽  
Machining Process ◽  
Cnc Machine Tools ◽  
Milling Machine ◽  
Cnc Machine ◽  
Geometrical Errors ◽  
Vertical Milling ◽  
Vertical Milling Machine ◽  
Accuracy And Repeatability

The aim of this paper overviews about to find out the errors that come from three axis CNC vertical milling machine. The errors come from, the CNC milling machine can be modelled into mathematical models and later on these error models will be used to analyse the errors in the measured data. Many errors from CNC machine tools have given significant effects toward the accuracy and repeatability of manufacturing process. There are two error sources come from CNC machine tools such as tool deflection and thermal distortions of machine tool structure. These errors later on will contribute to result in the geometrical deviations of moving axis in CNC vertical milling machine. Geometrical deviations of moving axis such as linear positioning errors, roll, pitch and yaw can be designated as volumetric errors in three axis machine tool. Geometrical deviations of moving axises happen at every axis in three axis CNC vertical milling machine. Geometrical deviations of moving axises in linear and angular movement has the amount of errors up to twenty one errors. Moreover, this geometrical errors play the major role in the total amount of errors and for that particular reason extra attention towards the geometrical deviation errors will be needed along machining process. Each of geometrical error of three axes vertical machining center is modeled using a homogeneous transformation matrix (HTM). The developed mathematical model is used to calculate geometrical errors at each axis and to predict the resultant error vector at the interface of machine tool and workpiece for error compensation.

scholarly journals Active vibration control for a CNC milling machine

2013 ◽  
Vol 228 (2) ◽  
pp. 230-245 ◽  
Author(s):  
DG Ford ◽  
A Myers ◽  
F Haase ◽  
S Lockwood ◽  
A Longstaff
Keyword(s):  
Control System ◽  
Tool Wear ◽  
Machine Tool ◽  
Vibration Control ◽  
Surface Finish ◽  
Machine Tools ◽  
Active Vibration Control ◽  
Milling Machine ◽  
Cnc Machine ◽  
Active Vibration

There is a requirement for improved three-dimensional surface characterisation and reduced tool wear when modern computer numerical control (CNC) machine tools are operating at high cutting velocities, spindle speeds and feed rates. For large depths of cut and large material removal rates, there is a tendency for machines to chatter caused by self-excited vibration in the machine tools leading to precision errors, poor surface finish quality, tool wear and possible machine damage. This study illustrates a method for improving machine tool performance by understanding and adaptively controlling the machine structural vibration. The first step taken is to measure and interpret machine tool vibration and produce a structural model. As a consequence, appropriate sensors need to be selected and/or designed and then integrated to measure all self-excited vibrations. The vibrations of the machine under investigation need to be clearly understood by analysis of sensor signals and surface finish measurement. The active vibration control system has been implemented on a CNC machine tool and validated under controlled conditions by compensating for machine tool vibrations on time-varying multi-point cutting operations for a vertical milling machine. The design of the adaptive control system using modelling, filtering, active vibration platform and sensor feedback techniques has been demonstrated to be successful.

A Reliability Analysis of NC Machine Tools Based on the Weibull Distribution

2015 ◽  
Vol 741 ◽  
pp. 763-767
Author(s):  
Hui Liang Li
Keyword(s):  
Weibull Distribution ◽  
Machine Tool ◽  
Machine Tools ◽  
Interval Estimation ◽  
Point Estimation ◽  
Numerical Control ◽  
Control Machine Tool ◽  
Failure Data ◽  
Nc Machine ◽  
Nc Machine Tools

In this paper, a series of numerical control machine tool truncated failure data collect.The data are assumed to be two parameter weibull distribution and related parameters is obtained and relevant inspection and test of hypothesis, it is concluded that the mathematical model of batch of nc machine tool failure interval time distribution.Relevant indicators to determine the reliability of nc machine tools, machine tool's observations, Machine tool observations, point estimation and interval estimation index value provide a theoretical basis for the research on reliability of machine tool.

Machine Tools Mechatronic Analysis

2006 ◽  
Vol 220 (3) ◽  
pp. 345-353 ◽  
Author(s):  
R Maj ◽  
F Modica ◽  
G Bianchi
Keyword(s):  
Machine Tools ◽  
High Speed ◽  
High Performance ◽  
Dynamic Behaviour ◽  
Traditional Approach ◽  
Optimization Technique ◽  
Numerical Control ◽  
Milling Machine ◽  
Mechanical Structure ◽  
High Speed Machine

High-speed machine tools show close interaction between the dynamic behaviour of the mechanical structure, drives, and numerical control. In order to support the designer of high-performance machines, a new analysis based on an integrated holistic mechatronic optimization technique is proposed and compared with the traditional approach. The proposed approach is applied to a three-axis milling machine for dies and mould production.

scholarly journals Modular design research of computer numerical control machine tools oriented to customer requirements

2020 ◽  
Vol 12 (4) ◽  
pp. 168781402091657
Author(s):  
Fei Li ◽  
Xudong Li ◽  
Hualong Xie
Keyword(s):  
Machine Tool ◽  
Machine Tools ◽  
Quality Function Deployment ◽  
Modular Design ◽  
Computer Numerical Control ◽  
Mapping Method ◽  
Numerical Control ◽  
Control Machine Tool ◽  
Control Machine ◽  
Customer Demands

In order to study the modular design of computer numerical control machine tools oriented to customer demands, the customer demand information model was established based on rough analytic hierarchy process and information entropy by analyzing and transforming customer demands. Based on the domain mapping method of axiomatic design and quality function deployment integration, the product function model and structure model of computer numerical control machine tools are established. Based on fuzzy clustering analysis, the module division of computer numerical control machine tools is studied, and the dynamic clustering diagram of computer numerical control machine tools is formed with MATLAB as the operating environment. Based on Technique for Order Preference by Similarity to Ideal Solution method, the scheme of computer numerical control machine tools module division is evaluated. Taking the horizontal computer numerical control machine tool products of Shenyang Machine Tool Group as an example, the module division is carried out. The example design and the result analysis prove that the module division system is very effective and fast.

Research on the 840D NC Machine Tool Production Process Monitoring and Management

2014 ◽  
Vol 577 ◽  
pp. 421-424
Author(s):  
Le Ping Chu ◽  
De Ming Xiao ◽  
Zai Yu Chen ◽  
Cheng Rong Pian ◽  
Nan Wu ◽  
...  
Keyword(s):  
Machine Tool ◽  
Production Process ◽  
Machine Tools ◽  
Numerical Control ◽  
Nc System ◽  
Nc Machine Tool ◽  
Nc Machine ◽  
Nc Machine Tools ◽  
Plc Program ◽  
Status Data

According to the communication principle of 840D numerical control (NC) system and internal data structure, the PLC program is developed to make 840D system state data transmit to the PC with the MPI channels; production status data real-time monitoring system based on 840D NC machine tools is developed, meanwhile, the monitoring and data management for NC machine tool production process status is realized.

Correct Use and Maintenance of Nc Machine Tools

2014 ◽  
Vol 651-653 ◽  
pp. 676-679
Author(s):  
Quan Fang Sun ◽  
Jun Ling Zhang
Keyword(s):  
Control System ◽  
Machine Tool ◽  
Machine Tools ◽  
Numerical Control ◽  
Numerical Control System ◽  
Nc Machine Tool ◽  
Important Index ◽  
Nc Machine ◽  
Nc Machine Tools ◽  
Reasonable Use

A country's level of Nc machine tool and ownership, is to measure the level of manufacturing and industrial modernization level of important indicators, is also an important index to measure national comprehensive competitiveness. Therefore, how to better use and maintenance of Nc machine tool is an important issue. This paper introduced how to reasonable use of Nc machine tools, as well as the use of the numerical control system and inspection.

Data acquisition and data mining in the manufacturing process of computer numerical control machine tools

2017 ◽  
Vol 232 (13) ◽  
pp. 2398-2408 ◽  
Author(s):  
Wei Wang ◽  
Hai Li ◽  
Pu Huang ◽  
Xinyu Zhang
Keyword(s):  
Machine Tool ◽  
Data Acquisition ◽  
Manufacturing Process ◽  
Machine Tools ◽  
Numerical Control ◽  
Process Data ◽  
Communication Architecture ◽  
Machine Performance ◽  
Five Axis ◽  
Siemens 840D

Networks of five-axis machine tools produce huge amounts of process data. These data directly reflect the running condition of the machine tool but are seldom used to examine the machine performance. This study proposes a new data acquisition method based on the Object linking and embedding for Process Control protocol without any additional monitoring equipment. The data collection principle is explained, and a client is developed based on the SIEMENS 840D system. Considering less influence on the manufacturing process, a communication architecture for the machine network is designed with a special computer transmitting the data to the server. A compression algorithm is applied to reduce the storage capacity of massive amounts of data. Finally, a method for predicting the future performance of the machine tool is proposed using similarity analysis of the time series. A Petri net model is also established to diagnose possible failure causes. These methods significantly improve the machine tool reliability and find potentially important information from the data in the manufacturing process.

Sign in / Sign up

Export Citation Format

Share Document