Discussion on the teaching reform of the hottest N

Discussion on the reform of NC practical training teaching

Abstract: This paper aims to cultivate practical talents who meet the actual needs of enterprises, and integrates the "NC programming and processing practical training" project and the "cam practical training" project of Fujian Institute of information technology as an integrated comprehensive practical training project, guided by the training of students' intelligent ability and guided by the working process; Take the actual task as the carrier and drive the training content with the project; Adopt behavior oriented teaching methods, introduce product processing into the training process, and build a "production practice based" training mode. It realizes the zero distance connection between NC teaching and NC post requirements

with the enhancement of comprehensive national strength, China is gradually becoming one of the world's manufacturing centers. As a representative of advanced manufacturing technology, numerical control technology has become more and more prominent in China's manufacturing industry, and the corresponding training of numerical control technology talents has also been included in the scope of China's scarce talent training. A considerable number of students and parents flock to this major because of its easy employment and promising development prospects. In this environment, colleges and universities are competing to set up numerical control majors. How to complete the training of students in just 2-3 years, so that they can meet the needs of employers as soon as possible, practical teaching is the key. As an important practical teaching link of higher vocational education, Fujian Institute of information technology highly values practical teaching. In recent years, it has not only invested a lot of funds and manpower to build a "national numerical control practical training base" with complete functions and advanced equipment, but also has been committed to various integrated teaching reforms and practical teaching reforms. In the cultivation of high skilled applied technology talents, Made active exploration and innovation.

1. Requirements of enterprises for NC talents

according to a series of training and research conducted by the education and development center of mechanical industry and the national NC system engineering technology research center of Huazhong University of science and technology on the demand for NC technical talents, enterprises have the following three levels of demand for NC talents, and the knowledge structures they need to master are also different

1.1 blue collar level

talents at this level refer to technical workers who undertake the specific operation and simple maintenance of CNC machine tools in production positions, that is, CNC operation technicians. It is required to master the knowledge of machining and NC machining process, the operation and manual programming of NC machine tools, and understand the automatic programming and simple maintenance and repair of NC machine tools. Most of these talents are organized and trained by secondary vocational schools, and many of them are trained from ordinary machine tool operators in factories

1.2, Gray Collar level

talents at this level refer to technicians who undertake NC programming and maintenance and repair personnel of NC machine tools in production positions

numerical control programmers: they are required to master the operation of numerical control and numerical control machine tools, be proficient in numerical control processing technology (such as process route selection, tool path selection, cutting parameter setting, etc.), master the professional knowledge of complex mold design and manufacturing, be proficient in 3D CAD/CAM software, and enter pro to specially develop needle catheter/E, UG, Mastercam, etc; Master CNC manual and automatic programming technology; This kind of personnel is in great demand with high treatment, and most of them are trained by higher vocational colleges

maintenance and repair personnel of CNC machine tools: they are required to master the mechanical structure and electromechanical joint training of CNC machine tools, master the operation and programming of CNC machine tools, be familiar with the characteristics of heterogeneous CNC systems, software and hardware structures, PLC and parameter settings, and be proficient in the mechanical and electrical training and maintenance of CNC machine tools. The demand for this kind of personnel is also large, and it is very scarce before the project, and its treatment is also high, which is one of the training objectives of higher vocational colleges. However, it is very easy to cultivate this kind of personnel, with wide requirements for knowledge structure, strong ability to adapt to NC related work, and requires a lot of accumulation of practical experience. At present, some of them are cultivated by higher vocational colleges, and most of them are cultivated by NC equipment manufacturers and flow into other enterprises

1.3 golden collar level

talents at this level refer to CNC generalists in production positions. Have and be proficient in the comprehensive knowledge required by NC operation, NC process programming, fixture design and NC machine tool maintenance and repair, and have accumulated a lot of practical experience in practical work, with a wide range of knowledge. It pays a high salary to be able to complete the selection of CNC system, the installation, training, maintenance and precision optimization of CNC machine tools. This kind of talents are cultivated from undergraduate and higher vocational schools, but they must be promoted by providing special training measures and guidance from famous teachers

according to the needs of enterprises for NC talents, with the existing conditions of higher vocational colleges, we can cultivate a large number of NC operation technicians and NC programmers, and a small number of NC generalists (NC maintenance talents have nothing to do with this article, which is not the scope of this article). CNC operators are excluded by some students because of their low entry threshold and low salary. Therefore, with the existing conditions, higher vocational colleges should put NC programmers and NC generalists as the primary training objectives. As the last training link leading to enterprises, it is worth discussing whether the current training system conforms to the training objectives of NC programming and NC general talents

2. Current CNC teaching system and existing problems

the current training system is arranged in the form of one-to-one, that is, one course corresponds to one course training, so as to strengthen the teaching effect of the course. For example, our college arranges two six week training programs for numerical control programming and processing technology, which mainly focus on the level of numerical control certification to train students' hands-on operation ability. This course training enables most numerical control students to master the basic operation and manual programming of numerical control milling machines and numerical control lathes through the certification of numerical control milling machines or numerical control lathes; A two-week "cam training" is arranged for the (MasterCAM) course, mainly for MasterCAM drawing, tool path and automatic programming, so as to strengthen students' understanding of the lessons

this training system is not ideal. Through NC programming and processing training, although most NC students master the basic operation and manual programming of NC milling machines and NC lathes through NC textual research, this operation skill is far from the actual requirements of enterprises. In enterprise production, NC milling machine processing generally adopts CAM programming, which requires operators to be skilled in parts clamping, calibration, program transmission and simple manual programming. In fact, as an advanced automation equipment, the operation of CNC machine tools is relatively simple, and manual programming has great limitations. The talents that employers really need are "engineering quality" who are proficient in CNC processing technology (such as process route selection, tool routing selection, cutting parameter setting, etc.), CAD/cam and CNC automatic programming, maintenance and repair of CNC machine tools. NC machine tool training because many students are surrounded by a machine tool, students with strong consciousness may learn some basic operation skills. Students with poor consciousness often drift away from the practice, and the practice effect is poor; Due to the influence of time, the number of machine tools, preparatory work, etc., and students' different work, a large number of students often fail to complete the processing or can't get the machining operation. Some students are quite complete. Several students use the same program to process workpieces to cope with the inspection, which leads to the reduction of the internship effect, and some students actually fail to achieve the internship purpose. Therefore, this kind of practical training system has not formed a comprehensive experimental training system with the main line of cultivating students' practical ability, analyzing and solving practical problems and innovation ability, and can not cultivate NC programming and NC general-purpose talents needed by enterprises. Therefore, the teaching reform must integrate numerical control training according to the needs of enterprises

3. NC Practice Teaching Reform -- integrate with the needs of enterprises

NC practice

according to the needs of enterprises for NC talents, taking into account the requirements of skill identification and certification, integrate the "NC programming and processing training" project and the "cam training" project of our college, arrange targeted practice step by step, and set the training content with different assessment objectives to meet the training requirements. For the first time, we arranged two-week internship for basic NC training, focusing on the operation of NC machine tools and manual programming. The second is the practical training of numerical control examination, which is arranged for two weeks of internship. This internship is mainly aimed at strengthening the training of numerical control examination. The third time is the comprehensive training of CNC machine tools and cam. Four weeks of internships are arranged to carry out productive comprehensive internships, introduce product processing into the training process, and build a "production practice based" training mode

3.1 NC basic training

due to the limitations of the types and number of NC machine tools, the "flow teaching method" training is advocated, that is, a class is divided into two large groups and several groups, a large group of NC lathes and a large group of machining centers. After a week, the training takes turns to reduce the per capita number of machine tools and improve the training efficiency. This training pays attention to the cultivation of students' professional skills, focusing on the operation of CNC machine tools and manual work, which will lead to high cost of programming. NC milling machine week requires students to master the two-dimensional drawing function of Mastercam, and train the two-dimensional programming and program remote transmission function of MasterCAM

3.2 NC certification training

after the tomb foundation training in the previous period, most students have been able to skillfully operate NC machine tools and carry out manual programming, so this internship is mainly aimed at strengthening the training of NC certification. Before the internship, let students choose the type of work they want to verify (it is best that half of the students in each class take the exam of CNC milling machine and half of the students take the exam of CNC lathe, so as to increase the utilization rate of machine tools). Integrate the key points and skill examination requirements of "numerical control programming and processing technology" into the training process. At the end of the training, students must take the vocational skill appraisal examination

3.3 NC comprehensive training

NC machine tool and cam comprehensive training is guided by cultivating students' professional ability; Training students' work process oriented; Adopt the behavior oriented teaching method, take the actual task as the carrier, introduce the product processing into the training process, and construct the training mode of "project driven training content"

this internship is completely guided by the working process, that is, each student is required to complete product programming and machine tool processing parts independently, and students are also required to cooperate with each other. The machine tool cannot be idle due to programming time, and the whole process is completely carried out according to the working process reference of the enterprise. The internship project can be that the students study the topics they are interested in by themselves and send them to the old commander for approval, or the old commander selects typical examples through enterprises and other tujing. The internship project Fuxin is determined and assigned by the old commander for approval two weeks before the comprehensive training, while the students can use their spare time to make process arrangements, formulate process documents and prepare procedures in these two weeks; Materials,/J tools, measuring tools, etc. can also be prepared in advance, which can minimize the problems of idle machine tools due to preparation and congestion during use, which is conducive to the continuation and connection of the whole training. Since students can study topics of interest by themselves and send them to the teacher for approval, students' interests and enthusiasm can be fully trained, and "I want to learn" is changed to "I want to learn". In addition, the internship will be arranged from two-dimensional to three-dimensional at the same time. Typical examples of enterprises will be selected as problem sets, and each student will complete

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