How to fix CNC machine tools, CNC repair experience

CNC machine tools are well-known contemporary high-tech machines, electricity, light, gas integration of the crystallization of complex electrical, pipe cross-proliferation of all kinds of NC system, products from the 70's to 90's, are not interchangeable, fault is the strange phenomenon, different, especially for large, heavy-duty CNC machine tools, which is very expensive, about several million dollars each, the installation time to adjust length (l a few months to over a year). Large-scale NC machine tools, there are hundreds of thousands of components, if one of has has a component failure will cause the abnormal phenomenon of machine tools, as well as wire connections, the pipe coupling with each other, it will neglect the problem, In addition, large, heavy-duty CNC machine tools are huge in size and in the absence of plants under conditions of constant temperature use, environmental impact can easily lead to failure. To this end, the NC machine tool, "difficult to repair" the problem on the U.S. before.
The introduction and manufacturing of our country for so many of CNC machine tools, how to quickly identify the failures, dangers, and promptly ruled out of? How can repair these expensive equipment? First of all, in my opinion to have a high degree of responsibility and the spirit of fearing no difficulties; Second, we must strive to master digital technology, contact my CNC machine tool repair for more than a decade of practice, in my opinion to watch many, many ask, many in mind that many thought practicing (over 5), and gradually improve their own technical standards and repair capabilities, to adapt to a variety of more complex situation, to solve difficult problems, repair of CNC machine tools.
First, it is necessary to watch many
1. To watch many of NC data
Many look to, to understand a variety of numerical control system and PLC programmable logic controller of features and functions; To learn more about CNC system alarm and troubleshooting; To learn more about NC, PLC machine parameter settings meaning; To learn more about PLC's programming language; To learn more about NC programming methods; to understand control panel operation and the contents of the menu; to understand and take the knife spindle motor drive performance and characteristics and so on, often a lot of numerical control information, look how? In my opinion we should give prominence to the main focus, to understand the origin and development, focusing on a thorough grasp of numerical control system are the basic composition and structure, master block diagram. The rest can "tour" and read, but every part of the contents must be focused on understanding, grasp. Because of numerical control system is a complex internal circuit diagram, and manufacturers do not provide. Therefore there is no need to find out in detail. Such as NX 1 154 five axis machine tools even the rotor blades using A 1 B10 system, we should focus on understanding the role of each part, the board's function, the destination interface, LED lights, such as the meaning. Now many models of CNC system, faster updates, different factories, different models often vary widely. To learn more about their similarities and individuality (uniqueness). Generally familiar with the CNC system SIEMENS repair person will not necessarily rule out the A-B skilled system failure, therefore, it is necessary to watch many, and constantly learning, updating our knowledge.
2. To watch many electrical diagram, electrical diagram digestion
For each electrical component, such as: contactors, relays, time relays, etc., as well as PLC input and output, to indicate electrical diagram 11. Let me give a simple example, such as 1A1 start for hydraulic pump motor contactor 1M generally in Fig bet its normally open, normally closed contacts of the future. Therefore, its corresponding page in a normally open or normally closed contacts 1A1, specify the content for the hydraulic pump motor to open for large-scale NC machine tool has dozens of electrical map pages, or even hundreds of pages. To understand that the function of each component should be of a very long time. Sometimes, one, the second look may also not sure the role of the components, it is necessary to watch and so many after the digestion and then write. Therefore, the startup has also mentioned that the hydraulic pump motor 1M, should also be clearly marked PLC of which are outside the output contactor Driven 1A1 action, to do the whole story, clearly. Electrical circuit diagram of some of the block diagram, such as the drive for each axis, only a block diagram, as long as the understanding of a certain control conditions (on-off situation), for detailed time and other things such as further study and consider. Individual countries are not the same as electrical symbols, they must first clearly understand. Factory prepared for the thick layer of several PLC STL, but also many look to master its programming language, in the read on the basis of Chinese Notes. This can be reduced substantially after the troubleshooting time, and if such failure happened again to become familiar with the electrical diagram, PLC STL, it is bound to cost a lot of time and often lead to wrong judgments.
3. To watch many hydraulic, pneumatic diagram, and depth of digestion
CNC machine tools for mechanical milling machine, hydraulic, pneumatic diagram, it is necessary to clarify its role and context. And 11 in the drawings indicate, such as Germany COBURG CNC gantry milling attachment, tool installation more complex, it is necessary to break down their plans, such as locking tool which moves the solenoid valve? Corresponding PLC exports, imports which are? Stated in the chart, so that the electrical to the mechanical action from the one pole in the end, while particular machines, electric part relatively close to the focus of understanding, such as Italian INNSE CNC Boring Milling Machine using electro-hydraulic proportional valve technology, we should focus on understanding its role and function, in particular, to understand and adjust adjust its data, static and dynamic when the proportional valve current and the corresponding equilibrium pressure pump, knows also understand electric machines, mechanical and electrical integration, have a variety of skills, such problem-solving skills on larger.
4. To watch many foreign languages, it is necessary to improve their professional ability of foreign language reading
Do not know foreign languages, especially English. Will not be able to read a large number of foreign technical information, simply relying on the translation, often are not very satisfactory. Watch foreign-language version of the technical information, the beginning of relatively difficult vocabulary many, many more look in mind, the commonly used word professional is the only way many future looks smooth, and a competent maintenance personnel to the basic tools to master the language.
Second, it is necessary to ask many
1. To ask many foreign experts
If you have training opportunities abroad or foreign experts to come to your factory installation and debugging tools, you'd better have the opportunity to participate. This is a best opportunity to study, because a large number of first-hand access to information and method of debugging tools and techniques. Such as in laser precision determination of the axis, the electric how to approach such an amendment. To many question, do not have to find out. Through this period of time will be of great benefit, be able to get a lot of internal information and manual (the user is confidential). When the machine into formal production, should also be frequent contacts with foreign experts maintain close ties. Through FAX, E-MALL, asked whether the problems were resolved Machine Fault further solutions and related information, can also be a special, special spare parts, which are very useful, while the CNC system agents, such as SIEMENS, FANUC, etc. Companies should also maintain good relations, many asked, could also be timely step in the numerical control system of deep information and related spare parts, also have the opportunity to participate in the NC system thematic study classes.
2. Malfunction, the master asked the operator to the failure of the entire process, and will not question, or just look like a question, so often fail to get the correct information at the scene will cause wrong judgments, so that complicating the issue, Therefore, in order to ask many, that question in detail and understand the entire process of fault occurred (beginning, middle, end), resulting in what the police number, then what components to operate, come across what to turn over what and how the external environment? To fully investigate the scene gain first-hand material on the basis of questions put fault correctly listed, in fact has solved half the problem, then analyze the solution for the experienced and skilled master operator, they are familiar with machine operator and processing procedures are familiar with, machine tools is very common understanding, close cooperation with them, for rapid troubleshooting very favorable.
3. To ask many other maintenance staff
When the other maintenance staff in the maintenance of machine tools, and you do not go when they came back, many should also ask, just what happened wrong? Is how to exclude him? Asked him to rule out the introduction of its methods. This is also a good learning opportunities. Others studying the correct troubleshooting skills and methods, in particular, to repair the old, experienced staff study,put their skills to improve their knowledge and standards.
Three, it is necessary to remember many
1. To record the various parameters)
Record machine adjust the focus after a good variety of parameters, such as NC machine tool parameters, PLC machine parameter, PLC program (more than the existence of disks), as well as the spindle and the tool motor current, voltage, speed and other data. Would also like to note the electric cabinet relays, contactors, such as in processing power and formal status (pull-in or disconnected) and the PLC for all input and output state of light-emitting diode LED (light dark, shining) or record the screen PLC state of IB (input bit), QB (output bit) is 0 or 1, such as IB1 =: 00000001, that is, I1.0 = 1, I1.1-1.7 = 0. This record for later analysis to determine the benefits of a great fault. Such as Germany SCHIESS happen CNC Vertical Lathe Z axis motor current relay action, we check the Z-axis motor normal working hours of the PLC state (0,1) and non-normal compared to the situation quickly find the cause of the malfunction, because one has Comparing the state of not only the relay, through adjustment, failure to immediately rule out the possibility.
2. To Record hydraulic, pneumatic state
Record same hydraulic, pneumatic or not in the formal processing of processing all kinds of pressure gauge, barometer pressure, the suction solenoid valve fault state, which adjust to judge is also a great help. Such as the United States keep out INGERSOLL OPENsIDE MASTERHEAD CNC milling machine hydrostatic dual-film technology, has more than 100 pressure measurement points, its high and low pressure machine features a direct impact on the normal action or not, the record of static and dynamic pressure is very important.
3. Carry a notebook, put the failures happen every day, how to exclude the process of record each and every human brain has been a long time easy to forget that "good memory, it is better written rotten," the benefits of a great record. CNC machine tools we have found some fault will often repeated, but always a few failures, as long as the check was how to resolve, and a few minutes troubleshooting, fast and good. Our company has a "running diary of CNC machine tools" and a "CNC machine tools ranked it the Record" to record information on these two, this is a CNC machine tools complete archives.
Fourth, it is necessary to think of many
1. To think of many, it is necessary to broaden our horizons
Often sometimes repair is not calm, not a good analysis, go to a dead end. COBURG remember that Y-axis gantry milling in the processing of a sudden shutdown, the screen on several occasions appeared dirty 1361Y-axis grating alarm, when we clean things Grating and grating the first 2 times and the results or downtime. Of a few days yet to be resolved, and finally found the real reason is because the Y-axis grating head to the wire between the amplifier EXE have questions, because Y-axis movement of long-term snakeskin tube bending, one of a position feedback lines well, to a certain location of the fracture caused by machine downtime. At that time, we only pay attention to static, neglecting the dynamics of 1321, there were once open-loop control police, but did not cause us enough attention. Therefore, we should put what happened alarm, fault conditions list them all, through, judge and integrated screening, prediction of the greatest possibility of failure, and then take actions to remove. "Exhausted suspect a blind alley and prospect", many think, give you a clear direction.
2. To think of many, it is necessary to know
Often when we are troubleshooting, and sometimes not find the real reasons for failure, after the failures continued to occur. Ingersoll remember to cotyledon root groove milling machine, spindle Sl happened 2 hours after the operation of "automatic stop" the failure of foreign experts at the time the order for a piece of board, seems to solve the problems, but after more than a month after they committed In other words, the order of a prepared plate or board, but did not find out the reasons for its damage. We have carefully inspected through the use of oscilloscopes and found that the "start" command the corresponding optocoupler particularly high anti-peak voltage, the addition of a separate grounding line, and its anti-optocoupler greatly reduced peak voltage, Since then, there have been no "automatic stop" failures, the reasons are because of the anti-peak voltage is too high, after a long time to optocoupler due to the gradual failure.
3. To think of many consider to be one step ahead
According to the frequency of failures happen, repeatability, life expectancy of electrical machinery, spare parts do a good job seriously. This is the machine to ensure continuous, the normal operation of an important job, non-do not. At the same time, some devices, as time delayed, eliminated, the market has been unable to buy tickets or buy very expensive, how do? Prior considerations, such as have a early 80's CNC machine tools used in photoelectric readers read with LOOP way into the processing procedures, may also use the opt-SPOOL way the original tapes (machine settings data), the event does not get sent, then the entire machines will become "dead" machine, with very serious consequences, because we are one step ahead to consider, in cooperation with relevant units, after numerous tests, using a floppy disk processor solves this problem to ensure that the machines can use so far. Many think, it is necessary to consider in advance, give leadership to rationalize the proposals, efforts to improve the external environment for CNC machine tools, from the temperature, dust, humidity, etc. want to approach several aspects, the use of retro-power voltage regulator, the installation of electric air-conditioning cabinets small house and other measures to enable the machine tool failure greatly reduced.
Friday, it is necessary to train many, that is, the practice of many:
1. To the practice of many, should have the courage to do, good hands
For maintenance personnel who will have to bold but cautious, we must dare to do, it will only talk about, not his fists, not CNC machine tool repair. However, the situation should be cooked no longer do, do not blindly, or else they will expand the fault, resulting in accidents, the consequences would be unthinkable. At the same time we still have good hands, first of all to familiar with the machine tool on the machine operation panel and the contents of the menu and do a good job operating ease, because the various models and system operation are the same. At the same time must also take full advantage of self-diagnosis of CNC machine tool technology to quickly solve the fault treatment. CNC technology is now more developed, it has since more and more consultation capacity. 1 A system such as B10, have special diagnostic software, Internet diagnostics.
2. To many practices, develop their own practical ability and mastery of experimental skills
Fault sometimes seem very vague, are hard to mechanical failure or electrical fault, such as gantry milling COBURG such a fault happened, which means that the Z-axis, whether to increase or to decrease, Z-axis ram always down and alarm. We have adopted a "separation of law", the electrical part of the control and completely separated from the original circuit, the Z-axis DC motor terminals on the line removed, and the other pass DC (220V power supply can communicate through the regulator, after four rectifier diodes give) received the electrical two-terminal and found that motor in accordance with the polarity of the DC transform change the rotation direction, remove the electrical fault, re-examination revealed that films are playing because of mechanical friction caused by ptosis pillow. There are a lot of other methods, such as "isolation method", "displacement method", "contrast", "percussion Act" and other methods can be used as an effective means to help us find and remove faults.
3. To many practice and learn the use of the device
Such as oscilloscope, multimeter, on-line detector circuit, short circuit tester, computer, programming, etc. can help us determine the specific circuit, inspection, in particular the PLC programmer, computer, it is necessary to skillfully use, be free to import, export machine parameters online test on the state, such as system initialization. This analysis of failures, especially for complex fault, has a lot to help solve the problem.
4. To many practices, the "small改小reforming"
Often happen in the normal work of a particular component damage (such as choice of switches, buttons, relays, etc.) and no spare parts, they do as far as possible, stick with the legitimate use of such means as the repair or temporary special ways in which machine tools can continue to work , to wait until after the restoration of spare parts. VDF CNC carts such as Germany's No. 2 in the Blade has five clamping pressure with micro-switch, one of two micro-switches accidentally damaged, no spare parts, we have adopted a "short connection" so that the touch pressure switch point in line with the PLC input conditions for the machine tool is not the normal work of the police can go on. Sometimes long after the use of machinery, worse positioning accuracy, positioning alarms generated in the machine tool can not re-adjust the circumstances under which a temporary amendment to machine parameters, to increase "tolerance" zone, so that it can work properly, in a word, such an approach also much.
5. To the practice of many, it is necessary to do-it-yourself repair board
CNC machine tools in general the reliability of the circuit board, and the failure rate is extremely low, go check the CNC machine tools in general, do not question the board first suspected. Such as the Siemens 850 system, sometimes 41NC-CPU alarm or 43PLC-CPU alarm, not the board has in fact a fault can be removed Stubbs Law, NC initialization methods such as hot and cold start the PLC can generally be excluded from trial and error. If indeed proved to be circuit board problem, it is necessary to make repairs. These plates (usually without the drawings) is expensive, there are generally a few thousand dollars ─ few million, for each enterprise "hard parts", the price too expensive, preparedness can not afford, so CNC machine tools is extremely good or bad circuit board important, once the circuit board without damage to spare parts, at other times, they repair bad shutdown is bound to seriously affect production. Sometimes only a very small circuit board failures, as long as careful inspection, it is not difficult to discover problems, we have repeatedly found that individual capacitor leakage, board, short-circuit fault, etc., some more complex circuit board failure, but as long as time, through inspection instruments, or be able to repaired; but there are some circuit boards in serious condition, especially the large-scale integrated circuits, maintenance difficulties, coupled with the original device no spare parts, can only be prepared in advance to buy board or send out repair. Do-It-Yourself repair board, has a great advantage, on the one hand, enterprises can reduce costs and solve the immediate needs, on the other hand, "Anatomy of Sparrows" familiar with the electronic circuit, develop their own analysis and practical ability is very useful.
Through the repair more than a decade of practice, we are foreigners designed CNC machine tools, especially large-scale NC machine tools are not perfect, there are also many problems and shortcomings. Through our study of NC machine tools, and deepen, to find out where the problem is one of boldly to improve on some issues, and achieved good results. VDF CNC carts such as Germany, the original design of two hydrostatic power bracket on one job, hydrostatic pump continuous operation, so that also charges electric pump also shortens the life span of imports. We modified PLC, an increase of two switches, only dozens of yuan, so that hydrostatic two brackets can be arbitrarily open or stopped, so that imports of extended pump life, a full year saving more than 20,000 degrees. Ingersoll Milling impeller shafts are the original design, the main head and deputy head only reverse milling, milling in the same direction without. High and medium pressure in the processing section 20 impeller rotor, the impeller because of the distance between the small and should not reverse milling, it can only be a first for processing. Through our research, subtly altering the limit two-way connection, an increase of PLC program, the result of almost no money, to achieve the same milling. 2 heads are now available at the same time processing, improve efficiency doubled, advanced 3 ─ 4 days processing rotor task. Therefore, we should further tap the potential of CNC machine tools, and better exert its power for the production of services.
Despite the numerical control machine tool fault complex, ever-changing, as long as we take seriously and cultivate a high-quality repair of mechanical and electrical integration team, look through the many, many ask, many thought, many training and accumulated experience and repair techniques, together, we must be able to rely mainly on their own strength, the CNC machine tool repair and make good use of, possession of a good.