Must be an excellent craftsman
CNC machine tools integrate drilling, milling, boring, reaming, tapping and other processes. The technical literacy requirements for craftsmen are very high. The NC program is the process of using computer language to embody the processing technology. Craft is the foundation of programming. If you don't know the craft, you can never say you can program.
In fact, when we choose the profession of mechanical cutting, it means that the early stage of employment is hard and rough. Machining engineers are, to some extent, experienced engineers. Therefore, it is necessary to spend time in the workshop, drying lathes, milling machines, grinding machines, machining centers, etc.; and then in the office to compile processes, estimate material consumption, and calculate quotas.
Must be familiar with the performance of various machine tools and the skill level of workshop masters. In this way, after 2-3 years of practice, you can basically become a qualified craftsman. You must learn from the workers with an open mind. Their decades of experience can save you a lot of detours. These experiences cannot be learned in books, and the choice of process is a choice that comprehensively considers equipment capabilities and personnel technical capabilities. Without the support and trust of employees, it is impossible to become an excellent craftsman. After such a long period of study and accumulation, you should meet the following technical standards and requirements:
1. Familiar with the structure and process characteristics of drilling, milling, boring, grinding and planing machines.
2. Familiar with the properties of processed materials.
3. Solid theoretical basic knowledge of cutting tools, master the conventional cutting amount of cutting tools, etc.
4. Familiar with the company's process specifications, guidelines and general requirements that can be achieved by various processes, and the process route of conventional parts. Reasonable material consumption and man-hour quota, etc.
5. Collect a certain amount of information on cutting tools, machine tools, and mechanical standards. In particular, be familiar with the tool system used in CNC machine tools.
6. Familiar with the selection and maintenance of coolant.
7. Have a common-sense understanding of the relevant types of work. For example: casting, electrical processing, heat treatment, etc.
8. Have a good fixture foundation.
9. Understand the assembly requirements and use requirements of the processed parts.
10. Have a good measurement technology foundation.
Proficient in CNC programming and computer software application
There are only dozens of programming instructions, and the various systems are similar. It usually takes 1-2 months to become very familiar with it. The automatic programming software is a little more complicated, and you need to learn modeling. But for people with good CAD foundation, it is not difficult. In addition, if it is manual programming, the basics of analytic geometry are also good! In practice, the criteria for a good program are:
1. Easy to understand and organized, everyone can understand the operator.
2. The fewer instructions in a program segment, the better, for the purpose of simplicity, practicality and reliability. From the perspective of programming, I think the commands are only G00 and G01, and the others are auxiliary commands, which are set for the convenience of programming.
3. Easy to adjust. It is best not to change the program when the machining accuracy of the parts needs to be fine-tuned. For example, if the tool is worn out, if you need to adjust it, just change the length and radius in the tool offset table.
4. Easy to operate. The programming should be compiled according to the operating characteristics of the machine tool, which is conducive to observation, inspection, measurement, safety, etc. For example, if the same part and the same processing content are processed separately in the vertical machining center and the horizontal machining center, the procedures must be different. In machining, the easiest way is the best way. As long as you have practical experience in the industry, you must agree with this sentence!
Proficiency in operating CNC machine tools
This requires 1-2 years of study, and the operation is all about the feel. Beginners know how to do it in their hearts, but their hands just don't listen to them. In this process, you should learn: the operation mode of the system, the installation of the fixture, the alignment of the part datum, the tool setting, the setting of the zero offset, the setting of the tool length compensation, the radius compensation, the installation and removal of the tool and the tool handle, and the blade of the tool. Grinding, measurement of parts (can skillfully use vernier calipers, dial gauges, dial indicators, dial gauges, inner diameter lever gauges), etc. The ones that can best reflect the level of operation are: horizontal machining centers and large gantry (moving beams, top beams) machining centers.
The practice of operation requires understanding! Generally speaking, the process from the processing of the first part to the qualified processing accuracy is required to be completed by the NC programming technician. If you can't operate the machine tool proficiently, you can't pass this level.
Must have good fixture foundation and measurement technology level
Fixtures and measurement technology play an important role in the quality of parts processing as well as the accuracy of machine tools, and are one of the symbols that reflect the level of craftsmen. The entire process system: the accuracy of the machine tool is guaranteed by the machine tool manufacturer, and the tools and cutting parameters are provided by the tool manufacturer. Generally, there are no major problems. Only the tooling and fixtures are specially designed by the craftsman for specific parts. Generally, the parts on the CNC machine tool are There is a certain degree of difficulty, so there are often unpredictable problems.
During debugging, the processing of the first part was unqualified, and more than half of the reasons were due to the unreasonable positioning, clamping point and clamping force of the fixture. The difficulty of analyzing the cause of the fixture is that it can only be qualitative, and it is difficult to quantify. If you have no experience in fixture design and parts clamping, it will be very difficult. For learning in this area, it is recommended to consult senior technicians who make precision coordinate boring machines. Accurate measurement level is one of the basic skills in machining. It is necessary to be able to skillfully use vernier calipers, dial gauges, dial indicators, dial gauges, inner diameter lever gauges, calipers, etc. Sometimes parts processing, coordinate measuring machine is not expected. Must be measured by hand.
Proficient in the maintenance of CNC machine tools
The so-called familiarity with CNC machine tools should:
1. Familiar with CNC electrical components and control principles. Can tell the name and function of each component in the electric box, and can understand the electrical schematic diagram. According to the electrical alarm number, the alarm content can be found out.
2. Understand the structure and transmission principle of the ball screw. Know which factors have a greater impact on the accuracy of machine tools.
3. Understand the structure of the bearings at both ends of the screw rod of the machine tool and its influence on the accuracy of the machine tool.
4. Understand the lubrication system of the machine tool (bearings, spindles, various kinematic pairs, gearboxes, etc.), and know the distribution of each lubrication point. The brand of machine tool lubricating oil and the normal weekly or monthly oil consumption.
5. Understand the cooling system of machine tools: cutting (water, air) cooling, spindle cooling, electric box cooling, etc.
6. Understand the main transmission structure of the machine tool, and the specific data characteristics between the speed and torque of each machine tool.
7. Understand the characteristics of the guide rail of the machine tool: is it a line rail or a slide rail, and what is the rigidity (carrying capacity)?
8. It can eliminate common operation failures (such as: exceeding the limit, wrong tool number in the tool magazine, etc.).
9. Proficient in various accuracy (static, dynamic) indicators and detection methods of machine tools.
10. Familiar with the mechanism of tool magazine and the principle of tool change.
It is difficult to meet the above requirements without more than 3 years of exercise.
