Field Diagnosis on CNC System Faults
Abstract
With the advancement of modern industrial production and development, CNC system technology has become an increasingly important part among different industrial production processes. As the core technology, an excellent cnc system can support the production process with high output and high efficiency. However, once CNC system fault occurs, it will interfere with the whole production process. Therefore, it is of great significance to have a clear understanding of the causes of CNC system faults and analyze a way to effectively diagnose and recover them. This article will provide a systematic analysis of CNC system fault, analyze the possible causes and countermeasures, and provide some effective recovery solutions.
1 Introduction
Computerized numerical control (CNC) system is a kind of sophisticated control system and has been widely used in industrial production methods. CNC machining is a process used to make custom parts on a computerized machine by automatically controlling cutting tools. It is widely adopted in many production systems, such as manufacturing of industrial components and machines, and has become the mainstream of modern industrial production. The CNC system is composed of CNC machine, CNC system software and numerical control devices. The CNC machine includes components like bed, column, spindle, protective cover, high speed brushless spindle motor and its drive unit, etc. On the other hand, the CNC system software consists of CNC language processor, CNC operating system, CNC transfer system and NC machine graphical display. In spite of its many advantages, the CNC system may fail for various reasons and this will lead to the error of the whole system. It is important to repair the CNC system promptly and accurately to avoid the interruption of production and keep the high yield. Therefore, in this paper, the causes of CNC system faults, the ways and methods of field diagnosis and recovery solutions are discussed.
2 Causes of CNC System Faults
In order to diagnose and rectify CNC system faults, it is necessary to understand the possible causes of such type of fault first. Generally, the faults may be caused by the materials, equipments, hardware, and programming.
2.1 Material Faults
Material faults refer to the material quality or structure of CNC components, such as low rigidity or unqualified material of cutting tools, insufficient lubrication, unsuitable pressure and medium form. In production, if the materials of the installed parts are not qualified, it not only results in poor machining precision, but also cause CNC system faults.
2.2 Equipment Faults
Equipment faults refer to the operation and maintenance of equipment, such as installation inaccuracy, too much residual stress, gap between the parts and too rigid or too loose parts. As a result, malfunctions of parts will occur, thus increasing the failure rate of the system.
2.3 Hardware Faults
Hardware faults refer to the damaged operating components in CNC systems, such as motor, motor drive, guide rail and machine tool head, etc. Once the hardware components are damaged, the system will be faulty.
2.4 Programming Corrections
The principles and processes of programming mistakes will also lead to CNC system faults. Program errors will bring serious consequences once they occur.
3 Field Diagnosis of CNC System Faults
In order to diagnose and repair the CNC system, certain diagnosis methods and skills are needed. Generally, the diagnosis processes should mainly include process analysis, fault description, on-site observation and elimination processes.
3.1 Process Analysis
In the analysis of CNC system faults, the analysis of production process is needed in order to find the root cause of the faults. Make a clear process program list, and pay attention to the parameter settings. Off-line testing can be conducted to reproduce the fault.
3.2 Fault Description
Fault description refers to the detailed information of the failure point of the CNC system, and it is carried out through the interaction between the field operator, engineer and other personnel. Generally, some questions may be asked, such as when the machine start up and stop, what is the machine rest position, what is the frequency of fault occurrence, what is the process of fault occurrence, after the repair of the fault, what is the recovery time, etc.
3.3 On-site Observation
This involves the testing of equipments, such as whether the operation power is at normal pressure, whether there is damage to the wiring, whether the operation voltage is appropriate, whether the connection is loose and whether the operation current is in the normal range.
3.4 Elimination Process
Elimination process of CNC system fault includes component replacement, component assembly and testing, etc. After the fault is confirmed, replacing the damaged components is the most direct way to repair the fault or replace them with qualified components. During the component assembly process, attention should be paid to the environmental conditions, installation order and effect of the component assembly. During the testing, the static and dynamic parameters of the components and systems should be tested to determine whether they can function normally.
4 Recovery Solutions
In order to avoid the CNC system fault, it is necessary to have a clear understanding of the whole aystem and take some practical measures to reduce the fault rate of the system.
4.1 Keep Spare Parts
In order to reduce the downtime due to CNC system fault, it is important to ensure the availability of the spare parts in the system. To ensure the replacement of components, some spare parts should be stored for quick replacement when necessary.
4.2 Implement It Properly
The improper implementation of CNC systems may easily lead to CNC system fault. To reduce the occurrence of such fault, it is necessary to ensure the correct implementation for the CNC systems. For example, the choice of materials and components, the performance of the oil film, the fixed connection and clamp of components and the consistency of the oil path should all be strictly assured.
4.3 Testing Regularly
Regular testing and maintenance of the CNC system can help to maintain the good performance of the CNC system and reduce the possibility of CNC system fault. Besides, it is important to check the status of the machine and spare parts regularly to prevent the unexpected downtime and reduce the damage of CNC system.
5 Conclusion
CNC system is a kind of sophisticated control system that plays an important role in modern industrial production. With the advance of it, CNC system failure has become a considerable factor that affects the production process. It is important to diagnose CNC system faults and provide some effective recovery solutions. This article has thoroughly discussed CNC system fault causes, diagnosis methods and recovery solutions. It is expected that this paper can provide some help to those with the same field of research.
