Do you really master the online diagnosis, offline diagnosis and remote diagnosis technologies of machining centers?

“Detailed Explanation of Online Diagnosis, Offline Diagnosis and Remote Diagnosis Technologies for CNC Machine Tools”

I. Introduction
With the continuous development of the manufacturing industry, CNC machine tools are increasingly important in modern industrial production. In order to ensure the efficient and stable operation of CNC machine tools, various advanced diagnostic technologies have emerged. Among them, online diagnosis, offline diagnosis and remote diagnosis technologies have become key means to ensure the reliable operation of CNC machine tools. This article will conduct in-depth analysis and discussion on these three diagnostic technologies of CNC machine tools involved by machining center manufacturers.

 

II. Online Diagnosis Technology
Online diagnosis refers to automatically testing and inspecting CNC devices, PLC controllers, servo systems, PLC inputs/outputs and other external devices connected to CNC devices in real time and automatically when the system is in normal operation through the control program of the CNC system, and displaying relevant status information and fault information.

 

(A) Working Principle
Online diagnosis mainly relies on the monitoring function and built-in diagnostic program of the CNC system itself. During the operation of CNC machine tools, the CNC system continuously collects operation data of various key components, such as physical parameters such as temperature, pressure, current, and voltage, as well as motion parameters such as position, speed, and acceleration. At the same time, the system will also monitor the communication status, signal strength and other connection situations with external devices. These data are transmitted to the processor of the CNC system in real time, and compared and analyzed with the preset normal parameter range. Once an abnormality is found, the alarm mechanism is triggered immediately, and the alarm number and alarm content are displayed on the screen.

 

(B) Advantages

 

  1. Strong real-time performance
    Online diagnosis can detect while the CNC machine tool is running, find potential problems in time, and avoid further expansion of faults. This is crucial for enterprises with continuous production and can minimize the losses caused by downtime due to faults.
  2. Comprehensive status information
    In addition to alarm information, online diagnosis can also display the status of NC internal flag registers and PLC operation units in real time. This provides rich diagnostic clues for maintenance personnel and helps quickly locate fault points. For example, by checking the status of the NC internal flag register, you can understand the current working mode and instruction execution status of the CNC system; while the status of the PLC operation unit can reflect whether the logical control part of the machine tool is operating normally.
  3. Improve production efficiency
    Since online diagnosis can perform fault detection and early warning without interrupting production, operators can take corresponding measures in time, such as adjusting processing parameters and replacing tools, thereby ensuring the continuity and stability of production and improving production efficiency.

 

(C) Application Case
Take a certain automobile parts processing enterprise as an example. This enterprise uses advanced machining centers to process automobile engine blocks. During the production process, the running status of the machine tool is monitored in real time through the online diagnosis system. Once, the system detected that the current of the spindle motor abnormally increased, and at the same time, the corresponding alarm number and alarm content were displayed on the screen. The operator immediately stopped the machine for inspection and found that the serious tool wear led to an increase in cutting force, which in turn caused an increase in the load of the spindle motor. Due to the timely detection of the problem, the damage to the spindle motor was avoided, and the production loss caused by downtime due to faults was also reduced.

 

III. Offline Diagnosis Technology
When the CNC system of a machining center malfunctions or it is necessary to determine whether there is really a malfunction, it is often necessary to stop processing and conduct inspection after stopping the machine. This is offline diagnosis.

 

(A) Diagnostic Purpose
The purpose of offline diagnosis is mainly to repair the system and locate faults, and strive to locate faults in as small a range as possible, such as narrowing down to a certain area or a certain module. Through comprehensive detection and analysis of the CNC system, find the root cause of the fault so that effective maintenance measures can be taken.

 

(B) Diagnostic Methods

 

  1. Early diagnostic tape method
    Early CNC devices used diagnostic tapes to perform offline diagnosis on the CNC system. The diagnostic tape provides the data needed for diagnosis. During diagnosis, the content of the diagnostic tape is read into the RAM of the CNC device. The microprocessor in the system analyzes according to the corresponding output data to determine whether the system has a fault and determine the fault location. Although this method can realize fault diagnosis to a certain extent, there are problems such as complex production of diagnostic tapes and untimely data update.
  2. Recent diagnostic methods
    Recent CNC systems use engineer panels, modified CNC systems or special test devices for testing. Engineer panels usually integrate rich diagnostic tools and functions, and can directly set parameters, monitor status and diagnose faults of the CNC system. The modified CNC system is optimized and expanded on the basis of the original system, adding some special diagnostic functions. Special test devices are designed for specific CNC systems or fault types and have higher diagnostic accuracy and efficiency.

 

(C) Application Scenarios

 

  1. Complex fault troubleshooting
    When a relatively complex fault occurs in a CNC machine tool, online diagnosis may not be able to accurately determine the fault location. At this time, offline diagnosis is required. Through comprehensive detection and analysis of the CNC system, the fault range is gradually narrowed. For example, when the machine tool frequently freezes, it may involve multiple aspects such as hardware faults, software conflicts, and power supply problems. Through offline diagnosis, each possible fault point can be checked one by one, and finally the fault cause is determined.
  2. Regular maintenance
    During the regular maintenance of CNC machine tools, offline diagnosis is also required. Through comprehensive detection and performance testing of the CNC system, potential problems can be found in time and preventive maintenance can be carried out. For example, perform insulation tests on the electrical system of the machine tool and precision tests on mechanical parts to ensure the stability and reliability of the machine tool during long-term operation.

 

IV. Remote Diagnosis Technology
The remote diagnosis of machining centers is a new type of diagnostic technology developed in recent years. By using the network function of the CNC system to connect to the machine tool manufacturer through the Internet, after a CNC machine tool malfunctions, the professional personnel of the machine tool manufacturer can perform remote diagnosis to quickly diagnose the fault.

 

(A) Technology Implementation
Remote diagnosis technology mainly relies on the Internet and the network communication function of the CNC system. When a CNC machine tool fails, the user can send the fault information to the technical support center of the machine tool manufacturer through the network. Technical support personnel can remotely log in to the CNC system, obtain information such as the running status and fault codes of the system, and perform real-time diagnosis and analysis. At the same time, communication with users can also be carried out through methods such as video conferences to guide users to troubleshoot and repair.

 

(B) Advantages

 

  1. Fast response
    Remote diagnosis can achieve fast response and shorten the fault troubleshooting time. Once a CNC machine tool fails, users do not need to wait for the manufacturer’s technical personnel to arrive at the scene. They can obtain professional technical support only through network connection. This is particularly important for enterprises with urgent production tasks and high downtime costs.
  2. Professional technical support
    The technical personnel of machine tool manufacturers usually have rich experience and professional knowledge, and can diagnose faults more accurately and provide effective solutions. Through remote diagnosis, users can fully utilize the manufacturer’s technical resources and improve the efficiency and quality of fault removal.
  3. Reduce maintenance costs
    Remote diagnosis can reduce the number of business trips and time of manufacturer’s technical personnel and reduce maintenance costs. At the same time, it can also avoid misdiagnosis and misrepair caused by technical personnel’s unfamiliarity with the on-site situation, and improve the accuracy and reliability of maintenance.

 

(C) Application Prospects
With the continuous development and popularization of Internet technology, remote diagnosis technology has broad application prospects in the field of CNC machine tools. In the future, remote diagnosis technology will be continuously improved and optimized to achieve more intelligent fault diagnosis and prediction. For example, through big data analysis and artificial intelligence technology, the operation data of CNC machine tools is monitored and analyzed in real time, possible faults are predicted in advance, and corresponding preventive measures are provided. At the same time, remote diagnosis technology will also be combined with emerging technologies such as intelligent manufacturing and industrial Internet to provide strong support for the transformation and upgrading of the manufacturing industry.

 

V. Comparison and Comprehensive Application of Three Diagnostic Technologies
(A) Comparison

 

  1. Online diagnosis
    • Advantages: Strong real-time performance, comprehensive status information, and can improve production efficiency.
    • Limitations: For some complex faults, it may not be possible to accurately diagnose, and in-depth analysis in combination with offline diagnosis is required.
  2. Offline diagnosis
    • Advantages: It can comprehensively detect and analyze the CNC system and accurately determine the fault location.
    • Limitations: It needs to be stopped for inspection, which affects the production progress; the diagnosis time is relatively long.
  3. Remote diagnosis
    • Advantages: Fast response, professional technical support, and reduced maintenance costs.
    • Limitations: It depends on network communication and may be affected by network stability and security.

 

(B) Comprehensive Application
In practical applications, these three diagnostic technologies should be comprehensively applied according to specific situations to achieve the best fault diagnosis effect. For example, during the daily operation of CNC machine tools, make full use of online diagnosis technology to monitor the machine tool status in real time and find potential problems in time; when a fault occurs, first perform online diagnosis to preliminarily judge the fault type, and then combine offline diagnosis for in-depth analysis and positioning; if the fault is relatively complex or difficult to solve, remote diagnosis technology can be used to obtain professional support from the manufacturer. At the same time, the maintenance of CNC machine tools should also be strengthened, and offline diagnosis and performance testing should be carried out regularly to ensure the long-term stable operation of the machine tool.

 

VI. Conclusion
The online diagnosis, offline diagnosis and remote diagnosis technologies of CNC machine tools are important means to ensure the reliable operation of machine tools. Online diagnosis technology can monitor the machine tool status in real time and improve production efficiency; offline diagnosis technology can accurately determine the fault location and perform in-depth fault analysis and repair; remote diagnosis technology provides users with fast response and professional technical support. In practical applications, these three diagnostic technologies should be comprehensively applied according to different situations to improve the fault diagnosis efficiency and accuracy of CNC machine tools and provide strong support for the development of the manufacturing industry. With the continuous progress of technology, it is believed that these diagnostic technologies will be continuously improved and developed, and play a greater role in the intelligent and efficient operation of CNC machine tools.