Development analysis of process design standard for optical window sheet machining

First, the development of optical cold processing

Cold processing of optical components in China was rare in the period of the Republic of China. By 1950s, optical processing technology was introduced almost from the Soviet Union and the socialist countries in East Germany. The optical cold processing is used for coarse grinding, fine grinding and classical polishing. At the same time, the processing efficiency is low, and the technical requirements of the operator are high. Each operator has to pass the technical post training for many years to get the job. Better skilled workers can finish the whole line from processing blank to polishing. At this time optical cold processing mainly relies on the skills and experience of technical workers to process parts, and the role of process design is not very important in this period. There was no strict technical standards, usually only in the processing requirements given in the process of size, surface accuracy and appearance requirements, and the processing parameters can be adjusted to not be prescribed by the operator according to each person's personal experience of self - adjustment process, as long as the production of parts that meet requirements of the drawings can be. Usually, every enterprise has a surplus of labor, and it is much less concerned about the efficiency of production than the demand for political ideas.

With the introduction of the spherical milling machine and the plane rough mill, the labor strength of the rough mill operator is relieved, and the processing efficiency of the rough mill is greatly improved. The process requirements have also been improved, but due to the low precision of the equipment, the demand for the post process has not changed, and the role of the process standard has not changed obviously. After the quasi high speed polishing ball, optical cold processing production efficiency increase rapidly, the workers clearer division of labor, the standard effect is obviously improved. The role of the craftsmen plays a decisive role in the production process. Operation standardization becomes the main content of the daily work of the enterprise. The "handicraft" of the old worker has become a supplementary role from the past domination. "According to the standard operation", "according to standard operation", "according to the standard production" and other slogans, become the basic of every modern enterprise production. The craft method, process route and process standard formulated by the technician play an important role in the production of the enterprise.

Two. The role of window processing technology

Process documents are the main technical documents that guide the processing of optical parts. Reasonable process rules are based on the correct process principles and practices, and are the crystallization of science and technology and practical experience. Therefore, it is a technical guarantee for obtaining qualified products, and all production and management personnel must strictly abide by it. For a large number of large production plants, due to the strict production organization, meticulous division of labor, and more detailed technical regulations, can the organization and command production. For a factory produced in a single small batch, the process regulations can be simpler. But no matter the scale of production, there must be process regulations, otherwise production scheduling, technology preparation, key technology research and equipment configuration can not be arranged, and production will be in chaos. At the same time, process regulations are also the basis for processing production problems, such as product quality problems, and the responsibility of each production unit can be defined according to the process regulations. The production in accordance with the process regulations is easy to ensure the quality of the products, to obtain higher production efficiency and economic benefit.

The process is gradually processed according to the steps of the process regulations. It is processed and inspected according to the requirements of the specified size. The production level and technological level of an enterprise can be reflected from the condition of the technical regulations. It is a measure of the level of the enterprise's technical level. Reasonable process rules can ensure the quality and efficiency of production, and also reflect the manufacturing level of the products, the state of the production equipment and the operation skills of the operators. However, the process regulation is not fixed. It is a summary of the practice of workers and technicians in the production process. It can be modified according to the actual production situation, making it continuous improvement and improvement.

At present, optical parts processing has entered the era of high speed machining. The output of optical components is large, and a large number of operators are needed. Most of the operators are from rural youth. They are usually unskilled, with a low level of culture and a lot of liquidity. If it is impossible to carry out long-term normative training, only brief basic training will be laid off. In order to deal with this situation, we usually decompose the process into a series of simple processing steps, so that each operator can only do one of them, and only if we strictly follow the requirements of specification. As long as the operator action is accurate, it was cooked, so as to solve the problem of staff training cycle. The adjustment of the machine and equipment for each process in the process of processing is adjusted by a special person. Thus, the shortage of technical workers was solved, and the production was carried out smoothly.

The formulation of processing technology has become very important. The process standard formulated by the technician directly affects the quality of the product. The technician is the maker of the processing technology, the equipment adjusts and the operators are the executors of the processing standards. After making process standard, the technician adjusts the state of the equipment by the equipment adjusts, and then operates by the operator.

In the whole process of processing, the process standards between the various processes are interrelated and must not be considered in isolation. In some enterprises, process design is carried out separately according to process and work steps, which can compensate for the defect that the technician only grasps the process technology and has no comprehensive understanding of the whole process. But doing this will inevitably lead to the problem of no connection between process design and process steps. The slight changes in the front process may change the process behind. Therefore, the process design must be coordinated, and a complete process design system should be established.

When the processing technology is designed, it is necessary to determine the processing method that needs to be used first. A plate processing can improve the processing efficiency, reduce equipment and personnel, but the fixture manufacturing cost is higher, is mainly used in large quantities and the upper plate number; single machining fixture manufacturing relatively low cost, convenient loading and unloading equipment parts, but take up more personnel. Before choosing, take a careful cost calculation and make a decision.

In the process of design to fully consider the following factors: the processing of parts of the glass properties, machining technical requirements, the enterprise existing processing equipment characteristics, fixture design and manufacturing level, can choose the auxiliary material characteristics, enterprise existing processing technology, the operator's skill. These factors should be taken into consideration, and they are complementary and mutually restrictive.

Three. Requirements for the technologist

As the designer of the process regulations, the role of the technologist must be in control of the whole process of processing, and the technologist must have many comprehensive qualities. Optical processing technician is the application of optical processing technology to solve various specific problems in optical processing and improve technology, research and application of new processing methods, new materials, new auxiliary materials, new technology and so on.

The skills to be mastered by a optical processing technician:

1. basic operations, experiments, optical mapping, mechanical design and other skills. Using modern mathematical methods and computing tools (such as computer operation, operation procedures), to solve practical problems in optical processing; be able to independently accomplish the optical machining process design, operation of mechanical equipment and analysis of machining results finishing; can accurately and skillfully draw optical parts drawing; in all kinds of engineering design, can use the modern engineering design methods, made creative achievements.

2. practical operation skills. Have certain equipment and instrument operation skills.

3. technological innovation skills. Through the actual processing experiments, a new understanding of the optical processing technology is formed and a new process is developed.

4. computer use skills. Mastering the use of computers, operating skills, and common applications, the computer can be used to solve technical problems independently.

5. expression skills. It is able to express technical opinions clearly and accurately in written and oral forms for technical guidance. A standardized technical document can be written in accordance with the prescribed format for the content of different processes.

6. economic analysis and evaluation skills for the process. The correct cost analysis and evaluation are made for the problems arising in the process of optical processing.

7. intelligence use skills. To grasp the methods of searching and utilizing technical information, we can make full use of the enterprise and the external information system, and get useful technical information in time.

The knowledge surface to be mastered by the optical processing technician:

In optical processing, processing principle engineer must master optical parts, familiar with all kinds of processing methods for optical components, standards and requirements for a comprehensive understanding, the performance of various glass properties and auxiliary materials of knowledge through practice, analysis of measurement method, familiar with optical parts measurement precision, operation methods and characteristics of proficiency in a variety of detection tool.

To master certain mechanical knowledge and understand the machining principle, mechanical structure, machining precision of various machine and equipment, and the skillful and accurate design of fixture and fixture.

There are some chemical knowledge to help improve the processing efficiency and prevent the surface corrosion of optical parts.

To understand the basic knowledge of economic accounting, to calculate the cost of the process, and to compare the economy.

In order to master the change of the processing technology level of the enterprise, the influence of the significant change of the workers on the processing process can be predicted and the corresponding countermeasures can be made.

Four. The influence of product quality fluctuation on process design

In the process of processing optical parts, the quality of the product often fluctuates. There are many factors that affect quality. It is difficult for us to accurately analyze the real cause of quality fluctuation at the moment. Most of the technicians choose to constantly change processing methods or other process conditions, and find a way to stabilize quality through various experiments. This solution often gets a significant effect, so this method is often introduced in many factories. As a part processing plant, we must first ensure the delivery of products, and then ensure subsequent product orders, so this is also a feasible method, which requires less energy and convenient use. However, if this phenomenon occurs frequently in the production process, enterprises must invest a large amount of manpower and material resources to correspond, and the technological capabilities of enterprises will be challenged. Managers and technicians run around like firefighters, disrupting the normal working order of enterprises, and daily work becomes a quality tracking after changing their working conditions, making it difficult to make long-term work plan and reduce work efficiency. The quality of products fluctuates frequently, and it also brings great pressure to the majority of direct authors. This situation makes the phenomenon of personnel turnover more serious, which further affects the process execution of enterprises, and the phenomenon of quality fluctuation is aggravating.

The craftsman should take more responsibility if it is determined to resolve the frequent fluctuation of quality. Most of the reasons for this phenomenon lie in the following aspects: the environmental changes in the processing, the changes of operators, the changes of raw materials, auxiliary materials and production batches, the changes of tooling and moulds, and the execution of process disciplines. Most of the quality fluctuation is regular, such as the annual spring rainy period, the most prone to corrosion marks on the glass. Therefore, in the process of design, it is possible to advance the fluctuation of quality in advance, and make process plans at different times in order to prevent the fluctuation of quality. In daily work, we monitor the process factors, record the influence of process factors on the quality of products and the effect of various process plans, and summarize the ways to deal with the problems. In the process standard design, standardized design is adopted, according to the characteristics of enterprise processing technology, all kinds of processing parameters are calculated by empirical formula, so that the process design shows a clear regularity. Therefore, we can make use of the regularity of processing technology and the regularity of product quality fluctuation, choose the appropriate process plan, improve the defective rate of products, and improve the production efficiency.

Five. Standardization of processing technology design

Process design standard, the parts to be machined material and technical specifications, business processing equipment, all kinds of auxiliary materials, processing level and processing environment as independent variables, calculate the process size selection process route, parts and precision machining allowance (in each process, the shape accuracy and surface roughness the degree of collocation), blank size and precision, the selected auxiliary materials, tooling and fixture structure and size, selection of processing equipment and equipment adjustment parameters and test methods for parts, from which to compare, finally make the best technology solutions. In this way, the prototype of the process design standard has been formed and the foundation for the follow-up work has been established.

Standardized manufacturing process design is not static. With the improvement of enterprise processing technology, the introduction of new materials and new equipment and the development of new processing methods, the design of processing technology must also change, and the design standard of processing technology should be revised. Through summarizing the practical experience of the operators and technicians in the production process, we should make modifications according to the actual production conditions, so as to make continuous improvement and improvement. In the process of the whole process design and correction, the effects of the modified content on the quality are quantitatively compared and recorded in detail.

Through the continuous revision of the process design, the technologist should revise the design standards. The revision of standards requires engineers to master a wide range of technical knowledge. Besides optical processing technology, they also need knowledge in mechanics, mathematics, statistics, computer operation and so on.

Darwin pointed out: "science is to organize facts, to find laws and to make conclusions. "

The optical processing technology is also a part of the science. After a long period of work practice, we have also realized that the process is also regular. Through a variety of technological phenomena, we can see the nature of it. The influence of the change of the technological conditions on the production results is summarized, analyzed and summarized, and the regularity of the change is found. Through the summary of the regularity, the technologist revised the design standard and improved the optical processing design standard. To solve the common problems in production process by regular way, most of the technicians and managers save a lot of time and energy, and do normal and orderly work. On the basis of the existing technological level, the quality of the products can be improved, and the methods to improve the production efficiency and reduce the labor intensity are found.

In the production process, there are still some factors that are influential, which are unknown to us. We can find it in this way, so as to determine the objective of solving the problem and improve the level of technology.

The standardization of processing technology design can be implemented after the technological level of the enterprise reaches a certain level. It needs the joint efforts of all the technological personnel in the enterprise and the assistance of production management staff to achieve it. It can be said that the standardization of processing technology and design must be supported by the whole management system. Standard process is not a short duration of time work, it requires the enterprise internal process design experience, from the processing technology of the enterprise developed, because the process of each enterprise, technological level, so as to move from not from outside standard. Therefore, enterprises should accumulate experience by bit by bit, and rely on unremitting efforts to achieve their own standardized design. The overall technology of the enterprise determines the success or failure of the standardization of manufacturing process design. Solidarity, mutual cooperation, mutual promotion and mutual improvement are the key to technological development.

The standardization of processing technology design is an indispensable process for enterprises to develop to a higher level to promote the development of enterprises. It can reflect the level of production and technological level of an enterprise, and it is a ruler to measure the technical level of an enterprise. In the actual production process, we constantly improve the manufacturing process design standard, making it more suitable for production needs, promoting the technical level of technicians and operators, improving production efficiency, reducing the defective rate and enhancing the economic benefits of enterprises.