Six Sigma was born in the United States: the US economy developed rapidly in the 1950s, and its products could meet consumer needs. However, in the 1970s, Japanese products entered the US market with excellent quality and low prices, which had an impact on American companies. Such as Motorola's TV, audio, mobile phone business, etc., prompting American companies to explore Six Sigma management to improve product quality.

Motorola ignited the 6SIGMA spark: Motorola recognized the key issues of product quality, and was inspired by Panasonic's application of Deming's quality management principle to reduce defect rates, and invested in research. In 1981, Motorola proposed to reduce bad products by 10 times within five years and use part of its sales profit to improve quality. Bill Smith, an engineer in the company's communications department, submitted a 6SIGMA mechanical design tolerance document to reduce or eliminate product defects. The company's communications department stated that the goal could be achieved within 6 years, so Motorola named the 6-year plan "6σ solution" and officially implemented it in 1985. 6SIGMA management. At that time, Motorola's quality level was 4SIGMA, that is, there were 6,800 defects in every million opportunities. The 6SIGMA solution set specific quality improvement goals. Two years after implementing 6SIGMA management, Motorola became the first company to win the National Quality Award in the United States, and won the NIKKEI Award in Japan's manufacturing industry the following year. In 1994, Six Sigma achieved great success in Motorola, achieving the 6σ target in many fields, with the manufacturing industry being about 5σ and the input-output ratio being 1:6.2.

"Wildfire" burns all over GE: GE led by Jack Welch implements 6SIGMA management, making it a competitive, agile and flexible company of excellence. In 1995, GE's quality level was between 3SIGMA and 6SIGMA, and due to quality problems, it caused an additional US$7 billion to 10 billion in scrap, rework, etc. Welch was determined to launch the quality revolution and announced the launch of the company's 6SIGMA quality behavior in early 1996, proposing to achieve the goals that Motorola has achieved in 10 years in five years. GE not only learns from Motorola's experience, but also enriches and develops the applications of 6SIGMA, such as applying variance tools to improve efficiency, focusing on helping customers win market competitive advantages, and carrying out many projects that help customers improve their production processes. 6SIGMA management method has achieved significant benefits in GE, with revenue of US$750 million at the end of 1998 and approximately US$1.5 billion in 1999. Analysts believe that the company's revenue will reach US$5 billion by 2010. GE also applies 6SIGMA to customer management, supply chain management, network management and other fields, continuously expanding its application scope.

Sigma (Chinese translation of Sigma and Greek letter σ) represents the degree of dispersion of data in statistics, that is, standard deviation; in the field of quality management, it is used to measure the level of quality control. > - If controlled at 3σ level, it means that the product pass rate is not less than 99.73%; > - If controlled at 6σ level, it means that the product pass rate is 99.99966%, that is, for every 1 million products produced, the unqualified products shall not exceed 3.4 , close to zero defects, is equivalent to an enterprise having extraordinary competitive advantages and excess profits. The meaning of quality management is "no matter what you do, there are only 3.4 mistakes in a million operations", which is a pursuit of perfect quality concepts and excellent management methods.

6SIGMA is a concept, philosophy, culture, method and tool that uses statistical methods to discover and find the laws of development of things, reflecting the corporate culture of continuous improvement, boundlessness and lofty learning.

6SIGMA - a symbol of high quality level and perfection: In terms of quality management, 6SIGMA requires product quality characteristics and services to meet customer needs and avoid defects in the production process. The σ value measures the quality level of the product or service. The error rate of the 6σ quality level is much lower than 2σ and 3σ. Mr. Dever said that 6SIGMA can achieve breakthrough performance levels and provide perfect services to customers.

Volatility is the real focus of quality: In the field of quality management, "average" often conceals "volatility", and "volatility" is the main problem in quality management. 6SIGMA regards solving "volatility" as its core problem, because "volatility" will lead to a large number of rework and repairs in the production department, causing cost losses. σ represents the standard deviation of the normal distribution and is used to characterize the magnitude of fluctuations in mass characteristics.

6SIGMA and processing capability: The CP value of the process (process) capability index is the predecessor of SIGMA. The CP value of 1.33 is equivalent to the effectiveness of 4σ, and the CP requirement of 6σ is equivalent to the CP value of 2.0. CP value is the result of comparing the variance requirements after data measurement, and is mainly used in manufacturing or engineering; 6σ management is the result of comparing the variance (customer satisfaction) after data measurement, and is more widely used. [Formula] In the 6SIGMA management method, the upper or lower limit of product quality and the enterprise's production capacity or processing capacity $B = 6\sigma$, so the processing capacity index $CP = T / B = T / 6\sigma$ ( $T$ is the product quality requirement). Usually the product quality distribution center does not coincide with the processing distribution center, and the average offset is 1.5σ, then the offset degree $K = 1.5\sigma / (T / 2) = 1 / 4$, and the actual processing capacity index $CPk = ( 1 - K)CP$. The processing capability index is a parameter that measures the equipment processing capability of an enterprise under the optimal control conditions. The defect rate calculated based on this parameter is the lowest defect rate that an enterprise can achieve and is the best value.

6SIGMA and defects: 6SIGMA uses three indicators: DPU, DPO, and DPMO to represent defects: > - DPU represents the average number of defects per unit product; > - DPO represents the average number of defects per opportunity, $DPO = $Total number of defects $/ $Total number of chances; > - DPMO represents the average defects per million chance (number of million chances).

DPO and DPMO are the same concept, and it is easier to judge a higher product quality level with DPMO. 5. Evaluation of 6SIGMA performance——Evaluation of circulation pass rate: Performance of the commonly used circulation pass rate KTY evaluation process of 6SIGMA method. Since each process of the production line may have defects, the final pass rate cannot reflect the losses caused by rework and repair of the intermediate process. Therefore, the concept of circulation pass rate is proposed. It is the product of the pass rate of each process, expressed by RTY (R is procurement, T is processing , Y is assembly). [Case] ​​For example, the product has three key links, the pass rate of raw material procurement is 95.5% (waste of 45,000PPM), the pass rate of personnel operation is 97% (waste of 30,000PPM), and the assembly pass rate is 94.4% (waste of 56,000PPM), so the product's The circulation pass rate is: $RTY = 0.955×0.97×0.944 = 87.4%$ (a total of 131,000PPM wasted). This circulation pass rate accurately reflects the efficiency and cost of production, and also reminds of waste problems in production.

6SIGMA quality management method almost perfectly meets customer needs, with a defect count of only 3.4PPM, which is a high-level and high-standard quality management.

It is a win-win approach for customers and organizations, starting from the entire business perspective, focusing on customers and businesses at the same time to obtain greater profits and stronger competitiveness.

6SIGMA quality management method is a flexible and comprehensive system approach that requires understanding customer needs, standardizing the use of facts and data, conducting statistical analysis, and focusing on management, improvement and business process reconstruction.

It is a management method that reduces the cost and risks of operating resources, aiming to reduce the risk of customers purchasing and the risks of products or service providers, and improve performance in all aspects.

6SIGMA Quality Management Method emphasizes the combination of quality improvement and economic accounting. Each quality improvement project must have financial results to improve customer satisfaction and corporate efficiency with minimal consumption and resource investment.

The 6SIGMA Quality Management Method is also known as the 6SIGMA Process Method. It uses process improvement projects as units to conduct project selection, design, assessment, implementation monitoring and financial cost analysis. When GE promotes 6SIGMA, it selects a large number of improvement projects and implements them in a team form.

The implementation of 6SIGMA can achieve high quality levels. For example, Motorola was awarded the National Quality Award, and GE's defects have been greatly reduced after implementing 6SIGMA, becoming an excellent company in the world.

With customer-centricity, we meet customer needs, enhance customer satisfaction, retain old customers, strive for new customers, increase market share, and increase operating profits. For example, GE's operating profit rose from 14.8% in 1996 to 18.9% in 2000.

Reduce inferior costs and increase returns: Dever, director of the Julan Institute of the United States, pointed out that inferior costs account for a large proportion of sales costs. 【Table 1: Inferior Cost Table】

It can be seen from the table that the proportion of inferior cost increases with the decrease in Sigma level. According to data, companies that implement 6SIGMA can reduce costs and increase revenue. For example, Motorola implemented 6SIGMA, saving $700 million in cost in 1991, and saving $2.4 billion in cost from the start of implementing 6σ. 4. Create a backbone team of the company. Through 6SIGMA's knowledge training and practical experience, cultivate a backbone team of employees with high quality, good skills and strong sense of responsibility to ensure the successful implementation of 6SIGMA. 5. Implementing 6SIGMA can achieve considerable benefits, such as Motorola's employee productivity increases by 126%, and shareholder share value increases by 4 times; General Electric (GE) implements 6SIGMA, achieving Motorola's 10-year target in 5 years, improving quality levels, revenue and profits , Revenue per share increased, shareholders' investment return reached 45% annually, plastic factory production capacity doubled, becoming the world's most valuable company.

1.1.1. Key Activities

1.1.2. Process improvement mode—DMAIC

Leadership is the key to the success of 6SlGMA management: 6SIGMA management adopts a top-down implementation method, and leaders need to play a core role in the whole process, and personally plan, commit, practice and implement it. For example, Motorola President Galvin and GE's Jack Welch, their decisions and actions play a key role in the implementation of 6SIGMA management. The leadership responsibilities include setting goals and requirements, ensuring resource supply, selecting outstanding personnel to participate, and taking strong measures. Measures to ensure the realization of 6SIGMA, etc.

Create a large number of 6SlGMA backbone teams: continuous education and training of employees are necessary factors for career success. Motorola pays about 4% of its salary each year to familiarize key employees with quality management concepts and tools, requiring employees to accept and implement 6SIGMA. GE invested $500 million in the first two years for quality training for all employees. Professionals completed 6SIGMA training for green belts or black belts. The black belt training lasted 4 months, and practiced while learning, and followed up learning to master it. Latest technology.

There must be a strong organization to ensure that 6SIGMA management is a systematic improvement of activities and corporate culture, and requires an effective organizational system and excellent talents to promote it. Its organizational form is generally divided into three levels:

Another organizational model can also be constructed from the perspective of human resources, resources and technology, and the members of the organization involved in the implementation of 6SIGMA have clear responsibilities and authority. 4. To implement the 6SIGMA Management Law, we must have a good corporate foundation: the 6SIGMA Management Law pursues the goal of excellent quality and is a scientific system with rich content, covering many aspects such as management specification system, employee quality, mathematical statistical analysis tools, etc. It is a major system project of the enterprise. . Implementation requires a certain overall quality and ability of the enterprise. Motorola has lasted for ten years and GE has been in use for five years to achieve significant results. However, 6SIGMA can first select advantageous projects in the department or process, and then accumulate experience before expanding to the entire enterprise. 5. 6SIGMA is linked to rewards and promotions: Motorola announced that employee rewards are related to the realization of 6SIGMA goals. GE President Jack Welch stipulates that managerial personnel promotion is linked to 6SIGMA, adjust the company's reward and punishment plan, link some funds to 6SIGMA results, and also Send most of the gifted stock options to employees participating in black belt training, which fully mobilizes employees' enthusiasm and trains a large number of 6SIGMA-type leaders.

[Picture: 6SIGMA Team Picture] The 6SIGMA team includes different roles, each with clear functions: > - Champion: The number of people is generally smaller than that of the Black Belt Master, most of which are part-time jobs. The main function is to supervise and guide the entire 6SIGMA activities, set goals, and select Black Belt Master and black belt. > - Black Belt Master: Full-time positions, the number is about 0.1% of the total number of employees in the company. The main function is to teach Black Belt 6SIGMA's strategies, skills and tools, check the progress of Black Belt and its team's activities, formulate plan goals for the team, and train Black belt. > - Black Belt: Full-time positions, with a total number of about 1% of the company's total number. It is the core resource and backbone of the company's continuous implementation of 6SIGMA management. Its main function is to select and guide team members to form a boundless team, and train team members to use 6SIGMA tools , training green belt. > - Green Belt: The number of part-time employees is about 10% of the total number of employees in the company. It is an important resource and backbone for the implementation of 6SIGMA management. Its main function is to select projects that have a direct impact on the current work and implement them, and train yellow Belt or leucorrhea. > - Yellow belt or leucorrhea: Part-time staff, mostly low-level managers or operators, and their main function is to participate in the specific implementation and cooperation of the project.

6SIGMA management core toolbox is based on the tools that black belt should master, including statistical tools at different stages:

Definition (D) stage tools: questionnaire method, histogram, hierarchy method, arrangement method, causal graph, bar graph, random sample and random sampling, hierarchy method (AHP), and quality function expansion (QFD).

Measurement (M) stage tools: process flow chart, causal chart, control chart, arrangement chart, scatter chart, measurement system analysis (MSA), failure mode analysis (FMEA), process capability index, and customer satisfaction index.

Analysis (A) stage tools: brainstorming method, multivariate graph, confidence interval for determining key quality, hypothesis test, box graph, histogram, arrangement graph, multivariate correlation analysis, regression analysis, analysis of variance (ANOVA).

Improvement (I) stage tools: Quality function expansion (QFD), experimental design (DOE), orthogonal test, response surface method (RSM), expansion operation (EVOP).

Control (C) stage tools: control chart, statistical process control (SPC), fault prevention program (Poka - Yok), process capability index (Cp, Cpk), standard operating program (SOPS), process file (program) control.

6Sigma management methods are suitable for all types of organizations and management fields, but not all organizations are suitable for immediate implementation. Only organizations with a fairly standardized management foundation and with good quality personnel can have the basis for implementing the 6Sigma management method. Currently, most of the first-class international or domestic enterprises that promote and implement 6Sigma management methods are promoted and implemented.

Birth time, origin and historical background: ISO9000 was formulated by the International Organization for Standardization in 1978 to summarize the experience of supplier quality assurance system for Western industrial countries, and is a product of the development of the world economy and trade; 6SIGMA was approved by Motorola President Galvin in 1978 to implement the " The 6SIGMA solution was born under the background of fierce competition in market quality that affects the survival and development of enterprises.

Purpose: ISO9000 aims to meet the requirements of customers and laws on product and service quality, with a business activity color; 6SIGMA pursues excellent quality, provides customers with defect-free products and perfect services, and improves corporate economic benefits.

Coverage: ISO9000 does not cover corporate finance; 6SIGMA emphasizes the combination of improvement and finance, and improves results through financial evaluation and analysis.

Training and education: The depth and breadth of ISO9000 are limited; the training and education of 6SIGMA has a long time, wide knowledge and rich content to ensure the effective implementation of 6SIGMA.

Function: 6SIGMA is a major business management strategy for the enterprise and has a breakthrough and improvement effect on the enterprise; ISO9000 has failed to achieve major breakthrough improvement.

Inheritance and development relationship: 6SIGMA is the inheritance and development of TQM.

Characteristics of the times: 6SIGMA is the product of the development of the times, and is adapted to the background of the continuous improvement of product and service quality requirements for modern life and economic activities.

System Method: 6SIGMA is a scientific and complete system method, with clear ideas and rich content, effectively integrating various tools, giving full play to the value-added role of tools on enterprises; TQM is difficult to achieve this.

Organizational form: TQM carries out work with QC group activities; 6SIGMA carries out work with team activities for improvement projects. Team members include highly qualified black and green belts that have been strictly trained, attaching importance to data analysis, problem-solving process and goal determination.

Application scope and effectiveness: 6SIGMA has a wide range of applications and focuses on effectiveness, and pursues maximization of economic benefits, which can enable multiple personnel to integrate with common goals; TQM application scope is relatively narrow, and its economic benefits are not as good as 6SIGMA.

6SIGMA, ISO9000 and TQM all emphasize continuous improvement and carry out the next round of improvements according to the PDCA cycle. However, ISO9000 is less used in enterprises, and the TQM improvement is not as strong as 6SIGMA. The improvement of 6SIGMA has undergone a fundamental change and is welcomed by more and more companies.

Understanding of Six Sigma Quality Management:

Implementing Six Sigma Management: Shanghai Mobile explores and summarizes the Six Sigma promotion and application method of "two major strategies and three stages".

The results of applying Six Sigma:

Directions for promoting the application of Six Sigma Management: In view of the successful practice of Six Sigma quality management method at Shanghai Mobile, the company will continue to carry out the Six Sigma project. According to the selection of project strategies and SERVQUAL service quality characteristics, select key departments and key processes to promote, such as improving signal coverage in Shanghai, shortening account managers' attendance time and business hall queuing time, improving billing accuracy and timely bill delivery rate, and providing business The department’s self-service inquiry terminal, etc.

1.1.3. Conceptual meaning

1.1.4. Implement application