Machine tool industry must-see: strengthen quality awareness and improve machine reliability

"The appearance can be imitated, the structure can be imitated, the function can be imitated, only the reliability can't imitate."

On September 2nd, at the annual meeting of the National University of Technology for Manufacturing Technology and Machine Tool Research held in Shenyang in 2010, Professor Zhang Genbao from the School of Mechanical Engineering of Chongqing University lost a blockbuster when he took office. He said that the reliability was poor and the frequency of failure was low. Export has become a key issue that restricts the development of China's machine tool industry.

Why can't the reliability problem be solved for a long time? In Zhang Genbao's opinion, it is still a question of consciousness.

Raising awareness is the key

"Why China's planes, satellites, rockets can ascend to heaven, but machine tool oil leakage has become an insurmountable problem? The fundamental reason is that the quality of leadership of the company's leaders is not enough!"

Jang Genbao said that all walks of life in the industry have realized that there is still a big gap between the level of China's machine tools and foreign advanced countries. Where are the gaps? For example, the accuracy of our products is high, but the accuracy of processing is poor; accuracy is poor; Less detailed analysis; poor user maintenance, these aspects increase the probability of machine failure.

All of these are poor performance.

"The function determines what the product can do. The performance determines the quality of the product's function. The reliability determines whether the machine's function can be completed in quality and quantity!"

According to Zhang Genbao, the main reason for the poor reliability lies in the fact that companies do not pay enough attention to reliability issues. For example, the design and R&D department only controls the function, while the manufacturing only controls the accuracy, and the reliability is not controlled.

In addition, in terms of performance, there is no reliable design method, no reliability analysis is performed, and no reliability test method is used. Of course, there is no accumulation of reliability basic data in the early stage.

It is understood that if a large-scale automobile factory loses one day's worth of production, it will lose more than 10 million yuan in output value. Therefore, for automotive manufacturers, the reliability of the machine tool is equivalent to efficiency. The important data for evaluating the reliability index of the machine tool is the average time between failures. The majority of foreign machine tools exceed 10,000 hours, and domestic machine tools are far below this figure.

It is no wonder that important customers are willing to spend several times more to buy imported machine tools, and there are doubts about domestic machine tools.

Jang Genbao believes that the reliability of domestic machine tools has reached a point where it cannot be resolved. In particular, the acceleration of the revitalization of the machine tool industry and the further improvement of the reliability level of domestic machine tools have become the unanimous cries of the industry.

Now many industry companies have also established the "customer first" business philosophy, to explore new technologies for reliability growth, and effectively improve the reliability of domestic CNC machine tools.

To satisfy customers, it is imperative to increase the competitiveness of domestic machine tools. Currently, CNC equipment users generally reflect that, except for special high-end numerical control equipment, most domestic CNC machine tools can meet the needs of users in terms of functions and performance, but in terms of product reliability, customers are worried. When users purchase products, they pay more attention to the maintenance of the machine performance or function, that is, the reliability of the product. No matter how advanced the CNC machine tools are, if they have frequent faults on the production line, they will not be favored by customers. Of course, they lose their market competitiveness.

Intensive testing is a means

How to solve? Because reliability cannot be imitated, even if there are drawings and process documents, others cannot be reliable. Therefore, improving reliability depends on the company's own lean management.

Zhang Genbao said that the reliability of CNC equipment involves various departments within the plant such as the design, manufacture, assembly, supply, and after-sales service of the host manufacturer; suppliers and collaboration vendors involved in matching parts and outsourcing; and various types involved. Machine operator user, maintenance personnel, and equipment management department. This is a systematic project that requires multiple departments and multiple companies to cooperate with each other. This collaborative environment is not only coordinated by various departments within the host plant, but also coordinated by the host plant and a number of suppliers and suppliers of external components, as well as collaboration between the host plant and a number of typical users.

As a "working machine" modern CNC machine tools, its reliability is more special. Must combine the domestic machine tool function and the operating environment as well as the reliability exists the specific question, studies the coordinated environment the high efficiency reliability technology of the numerical control engine bed, provides the technical support for the effective promotion domestic China numerical control machine bed reliability level.

Although in recent years, China has conducted basic research on the reliability of CNC machine tools, and conducted on-site tracking and reliability assessment of CNC lathes and machining centers, and achieved phased results. However, due to the introduction of high-tech CNC machine tools, new failures and failure modes have emerged. In order to further improve the reliability level of domestic machine tools, it is necessary to develop and apply emerging high-efficiency reliability technologies to solve the new problems of the reliability of CNC machine tools.

However, in any case, to ensure the reliability of products, we must do more reliability tests.

Zhang Genbao said that the research on reliability test technology includes the development of early fault excitation devices; the development of testing platforms for complete machines and functional components; the testing of stress and deformation of complete machines and functional components; the study of machine tool running status and fault information collection and processing technologies; Retention testing technology research.

Guaranteed reliability

According to the division of Zhang Genbao, the machine tool production modes are mainly divided into three types, which are nearly single piece production, mass production and multi-variety small batch production.

For nearly single piece production, the typical processed products such as aircraft and rocket parts products have small quantities and are almost single pieces, and the requirements for products are the first to be cost-reliable. For this reason, the accuracy of the machine tool is very high.

The mass production of products such as automobiles, due to the large volume of production, is generally the production line flow operation, the process is mature, and the consistency of the required parts is good, which requires the processing equipment reliability is very high.

Most of the parts processed by machine tools now belong to many varieties and small batches, such as steam turbines and generators. The volume of products is small, about 100 pieces. Due to the variety of varieties, it is required that machine tools be manufactured on demand, which also makes reliability control difficult. At the same time, due to the user's "extensive" use, it also increases the chance of machine failure.

According to Zhang Genbao statistics, more than 40% of product failures are caused by purchased parts. Therefore, companies must increase the reliability of their products. First, they must have a check on the reliability of purchased parts.

He suggested that the reliability control of purchased parts should be moved forward and the supplier should be supervised to build reliability capabilities. Reliability should be used as an entry condition to specify the supplier's reliability value and the failure information should be fed back to the supplier.

However, all of these are based on the premise that companies have increased their sense of reliability. Therefore, Zhang Genbao concluded that in order to improve reliability, awareness must be given first, competence is the core, design is the source, outsourcing should not be ignored, assembly is the key, trials are the basis, and use is the guarantee.