Just In Time (JIT) was first proposed by the Americans and later spread to Japan. It was a production method implemented by Japan's Toyota Motor Company in the 1960s. It was created by Mr. Naichi Ono, who was once the deputy general manager of Toyota Motor Company, after 15 years. Based on the idea of ​​eliminating waste and reducing costs, it is a product that adapts to the market demand of "multi-variety and small batches". This production method helped Toyota overcome the first energy crisis in the 1970s, and then gradually promoted it in Japanese and global enterprises, becoming a highly anticipated production management technology.

On-time production is a management model that aims to accurately determine the operating efficiency of each process link in the production process, and to accurately plan according to orders and eliminate all invalid operations and waste. It is also called zero-inventory production. Simply put, it is to send the appropriate raw materials and parts to the right place at the right time in the right quantity. JIT technology changes the traditional idea. In the production system, the demander decides the relevant elements of the supply of materials. The supplier supplies materials on the order of the demander and ensures the quality of the materials. This idea of ​​supplying according to the demand can improve work efficiency and economic benefits.

On-time production method originated from Japan's Toyota Motor Company. The basic idea is to "product the required products only when needed, as needed". It pursues a production system with no inventory or a minimum inventory. The core is production planning and control. and inventory management. JIT takes on time production as the starting point to expose waste in production, and then adjusts equipment, personnel, etc. to reduce costs, simplify planning and improve control levels. In terms of production site control, its basic principle is to produce the correct quantity of parts or products at the right time. The core control technology is the Kanban system, but JIT is not just Kanban management.

The basic principle of JIT production method originates from the supermarket management method that requires fixed supply, that is, the supplier delivers the goods to the required location at a specified time according to the order subpoena (kanban). Applying to manufacturing is to "production of required products as needed when needed," and pursue a production system without inventory or minimum inventory through production planning and control and inventory management. Toyota's JIT production method has the following important supporting technologies, means and methods:

"Inverted" production method: Unlike the traditional "promotion" production method, JIT is a reverse pull-up management method. Starting from customer needs, the production process is promoted in reverse. The previous process accurately meets the next process in terms of time and quantity. The demand for products can effectively curb blind overproduction, reduce the volume of products in production, improve productivity and production system flexibility.

Eliminate all forms of waste: The core of JIT production mode is to pursue a production system without inventory or with a minimum inventory, and the basic principle is to "eliminate all forms of waste." Toyota defines seven types of waste, including overproduction, handling, inventory, waiting, process, action, and waste of product defects. JIT believes that overproduction is the root of many problems, and reducing inventory can help expose problems, promote continuous improvement, and reduce production costs.

Respect human nature and mobilize people's enthusiasm: corporate activities cannot be separated from human participation, and the success of JIT production methods depends on cooperation and coordination among personnel. Toyota has cultivated people with knowledge, ability, motivation and professionalism, eliminates adverse factors in production and operation, and achieves the flexibility of on-time production and production systems.

Good external collaborative relationship: In modern industrial society, division of labor and cooperation is crucial to improving labor productivity. The unique "reverse" production organization method of Toyota's JIT production method requires the understanding, cooperation and joint improvement of collaborative enterprises. Good external collaboration relationships are an important support for the on-time production method.

JIT is an ideal production model. It sets the highest standard of zero inventory, provides direction for enterprise improvement, and provides a continuous improvement approach to "reduce inventory - expose problems - solve problems - reduce inventory".

The JIT production method takes "geting maximum profit" as the ultimate goal of corporate operations, takes "reducing costs" as the basic goal, and strives to achieve this goal by "completely eliminating waste". Toyota believes that factors that do not bring additional value are waste, such as overproduction, handling, inventory, etc. The specific production goals of JIT include:

Quality objectives: The minimum amount of waste is required. JIT requires the elimination of various unreasonable factors to ensure that every process in the processing reaches the optimal level.

Production objectives: The lowest inventory, JIT regards inventory as a proof of problems in the production system; reduce parts handling, reduce handling volume, save assembly time and reduce assembly problems; reduce machine damage rate; and minimize production batches.

Time goal: The preparation time is the shortest, and the preparation time is related to batch selection. If the preparation time tends to zero and the preparation cost also tends to zero, it is possible to use extremely small batches; the production lead time is the shortest.

JIT production is not only a production technology, but also a new management model, involving product design, production planning, equipment improvement and other aspects. The following three principles need to be followed to realize JIT:

Process assembly line: The product does not stagnate within and between processes, and is produced like an assembly line. The process is arranged in the processing order within the process to realize the processing and assembly of single-item products.

Determine the beat by the quantity of necessary products: The production speed of the product is determined by the quantity of necessary products. The time for producing a necessary part or a necessary product is called the beat. The formula is: beat = daily labor time / daily necessary products. Focusing on the beat, focusing on people's effective labor, the "standard operation method" is used for efficient production. When the production rhythm changes, adjust the number of workers to make the workload full. Because workers are multi-tastic, they can fully utilize the labor force.

The latter process drives the production of the pre-process: the latter process receives the necessary quantity of products from the previous process when necessary, and the previous process only produces the quantity of the received part of the product. This production method is controlled by receiving kanban boards and indicating kanban boards, which is also called a post-supplement production line.

JIT's eight management projects aim to detect bad links on site, improve them through full participation, and eliminate obvious and hidden waste, including:

Production performance management table: record the differences and abnormal contents of each process and production line in each time period, and make the abnormality superficial and promote the improvement of problems. Managers need to conduct investigations, analysis and formulate improvement plans.

Improvement plan: clarify the specific projects, responsible persons and completion dates of the improvement activities, establish a traceable ledger, formulate plans to effectively promote improvement and display them on site, so that on-site personnel can record problems and propose improvement plans, and match them with the production performance management table. use.

Standard operation table: reflects the will of on-site managers, stipulates the operating sequence of operators and the standard operating time of each process, and allocates the work content with beats to ensure stable and efficient production of high-quality products in a waste-free order.

Abnormal display board: When an abnormality occurs on the work site, the abnormal conditions of the process and the speed of production progress are displayed as soon as possible, and relevant personnel are notified by lighting the lamp to achieve rapid response.

Production progress board: The production progress is divided into three categories: normal, too fast, and too slow. The production progress status is judged based on the inventory in the storage area. During implementation, judgment standards must be formulated to detect problems in a timely manner and grasp the production progress.

In inventory quantity control: set inventory period and control inventory, clarify inventory stacking methods, period quantity and operation methods, and distinguish between normal and abnormal situations. Implement first-in, first-out and product classification management in the warehouse to facilitate finding the causes and seeking countermeasures when abnormalities occur.

Equipment utilization table: Record the equipment utilization with curves, investigate and analyze the reasons for low utilization and improve it, thereby improving production efficiency.

Work hours management curve table: Based on the benchmark monthly working hours, compare and evaluate the actual working hours that occur in the month (the same day), grasp the daily performance situation, and aim to reduce working hours, it can be matched with production performance management tables, standard work tables, etc. use.

Reducing costs is the basic goal and starting point of JIT production system: the market's demand for diversified and personalized products challenges traditional mass production methods to reduce costs. To survive and develop in competition, enterprises need to organize multiple varieties and small batch production at high quality and low cost. The JIT production system is based on the purpose of reducing waste and reducing costs. It is committed to eliminating excess products and personnel in the factory and organizing flexible production according to market demand.

Timely production and reduced human consumption are the essence of JIT production system: timely production refers to "production of necessary products in necessary quantities within necessary time", and the production process and inventory management are controlled through the "Kanban method" to complete the assembly process As a starting point, the latter process is ordered to the front process to effectively stop excessive production waste and avoid inventory waste. By setting up U-shaped mechanical devices and cultivating multi-capacity workers, the number of workers increases and decreases the number of workers according to the output changes, reducing idle work waste and reducing costs.

Balanced production and standard operations are important means of JIT production system: Balanced production requires the same production line to produce multiple products at a balanced daily basis. Not only should the production quantity and variety be balanced, but the planning should also be balanced and flexible. Achieve production balanced requires shortening the production cycle of components, which can be achieved through single-piece flow production or shortening the transformation time of small batch production operations. Standard operations are to standardize a series of work contents that an operator is responsible for within standard time, including three elements: cycle time, operation procedures, and standard survival capacity. They are an important prerequisite for achieving single-piece mobile production.

The self-discipline and creative thinking system are the guarantee for the implementation of JIT production system: the JIT production system is self-disciplined to create an environment. If the equipment can automatically detect bad products and stop running, workers can promptly detect and deal with defects. Enterprises need to implement the "people-machine" self-discipline management system that needs to be improved. The creative thinking system uses the proposal (rational suggestions) system to encourage operators or quality management teams to propose improvement measures, which plays an important role in solving on-site problems, improving operational transformation methods, and revising standard operations.

The preparations for timely production involve multiple aspects, and the specific content is as follows: [Table 1: Preparation for timely production]

JIT production methods are rich in content and have strict requirements in variety, quantity, time and quality configuration. "Kanban" management is an important tool, but the role of Kanban requires process integration, production balance, and production synchronization. Effective implementation of JIT production methods requires matching internal and external environment and conditions:

A perfect market system: JIT production mode requires a developed macro environment such as commodity market, labor market, capital market, information market, etc., and "less people" relies especially on a perfect labor market. With the development of China's economy and the improvement of the market economic system, better macro conditions will be created for the implementation of JIT production mode.

Establish supply chain management concepts and awareness: Enterprises should integrate internal and external resources and establish long-term strategic alliances with suppliers and users. For example, Dell's direct sales model works closely with suppliers and customers to share information in real time, creating a favorable external environment for JIT production methods.

Shaping an effective organizational culture: Corporate culture is the soul of the enterprise and the fundamental guarantee for the realization of management methods. Enterprises should advocate a cultural atmosphere suitable for JIT production methods, so that employees can accept their values ​​and code of conduct. For example, GE's Jack Welch transforms the company's culture. If Chinese companies want to implement JIT production methods and ensure product quality, they also need to pay attention to culture. Renovation.

Entrepreneurs should have a strong sense of crisis: JIT production mode arises in the context of crisis, and enterprises are currently facing challenges such as scarcity of resources and internationalization of competition. Entrepreneurs should have a sense of crisis and realize that corporate competition is ultimately a competition for talents.

Employee training: Employees’ knowledge and skills are the main source of competitive advantages for enterprises. Companies that successfully implement JIT production methods often have excellent "all-rounded" employees. Enterprises should establish JIT concepts within the organization and train employees to become "all-rounders" with a variety of skills. At the same time, they should study the experiences and lessons of related companies and promote production synchronization and balance.

Modern information technology that supports JIT production methods: JIT production methods require efficient information exchange between internal and external organizations, and various information systems support and cooperate with each other. Computer technology, network technology and communication technology are the basis for ensuring smooth logistics, capital flow and information flow, achieving rapid response to customers, and effectively implementing JIT production methods.

3.3.1. Basic means

3.3.2. Specific means to achieve timely and appropriate production

3.3.3. Management tools for realizing timely and appropriate production—Kanban

3.3.4. Important means to realize JIT production—Kanban management

The effective implementation procedure of JIT production system can be divided into the following six steps:

Determine goals: Corporate leaders need to have determination and a global perspective, determine specific reform goals that are small but not big, and ensure that the goals are approved by the highest leadership (organization).

Formulate reform plans: carry out research, including on-site visits, interviews with employees, collecting information and information, predict prospects and conduct customer needs surveys, formulate reform strategic plans, covering the introduction of medium- and long-term plans and annual implementation plans.

Establish an effective work organization: establish a steering committee composed of unit leaders and top management personnel, formulate relevant charters, select pilot content, scope, time, and employee objects, determine implementation plans, task instructions, and evaluation standards, and promote the sharing of experience and lessons , provide support and guarantee for the pilot.

Develop an implementation plan to ensure the successful pilot:

Comprehensive education or training: hire experts to conduct full-staff training to let employees understand the relevant content of the "JIT production system", such as what it is, its relationship with itself, benefits, requirements, and how to coordinate work, coordinator training, etc., so that employees can participate in the implementation of the reform .

Formulate regulations: Prepare relevant regulations to change the systems and guidelines for employees' work, make the "JIT production system" a part of the corporate culture and create greater benefits for the company.

Although the principle of JIT is simple, it requires multiple guarantees when implementing it. The following issues should be paid attention to when applying:

Implementing production streamlined means "moving the warehouse into the factory": production streamlined may lead to messy entrances and exit storage, making it difficult to find products and raw materials, causing production interruptions and safety hazards, so the "5S" for on-site management “The activity is very important.

Reliable resource guarantee: On-time production requires the establishment of an effective system in an environment with sufficient resources. Adequate resources not only refers to the number and type of content, but also requires delivery to the specified location in the right form at the specified time.

Small-scale production: JIT production method pursues zero inventory, produces according to market demand, and requires small-scale production. This requires that the production schedule is flexible, can be adjusted according to demand, the production line has flexible production capacity, and the switching procedures are simple and easy to operate and fast when changing product combinations.

Long-term and reliable partnership with suppliers: On-time production requires suppliers to ship in small batches and frequently, strictly abide by delivery time, provide high-quality parts, and be able to respond to order changes in a timely manner. Therefore, enterprises must select a few excellent suppliers, establish long-term and reliable cooperative relationships, share information, and jointly solve problems.

Complete logistics platform: The basic social logistics platform (transportation lines, nodes, traffic management, etc.) must ensure smooth transportation, and on-time logistics also requires high-efficiency and low-cost transportation loading and unloading methods.

Reliable quality assurance system: On-time production requires seamless connection between supply and production lines. It is necessary to establish a complete quality management system covering suppliers, manufacturers, agents and retailers to ensure that raw materials are qualified, high-quality production, safe transportation, supply and Good after-sales service and pursues zero defects in the product.

Attention to human resource development: JIT production mode requires everyone to participate and improve together. Therefore, we must attach importance to human resource development and utilization, be people-oriented, conduct education and training, give the personnel on the work site the power and responsibility to deal with problems, cultivate team spirit, enhance cohesion and collaboration Problem-solving ability.

As a service industry, the strategic goal of implementing the JIT method is to provide satisfactory services to customers and strengthen competitive positions rather than reduce inventory. The process of applying JIT is as follows:

Design work flow: The work flow of foreign trade enterprises includes multiple links such as customer inquiries, establishing work files, and inquiring suppliers. Before the transaction is completed, shortening the quotation response time is the key, and basic data management is required to understand product-related information; master the movement of the airline in the delivery stage and select the best shipping route; strengthen contact with relevant departments in the foreign exchange settlement stage to shorten the foreign exchange collection time.

Total quality management: Strengthen the quality awareness of business personnel, improve the accuracy of documents, adopt a secondary audit system, and establish a quality auditor to conduct a secondary review of important documents. Establish a problem coordination team, composed of all department personnel, and communicate and coordinate weekly to resolve problems encountered in JIT implementation.

Introducing demand-driven plans: Establish a demand-driven plan based on the characteristics of the service industry, and accurately predicting customer needs is the key. By analyzing the supply and demand situation of international market products and customer ordering rules, preparing the supply can shorten the delivery time and prepare necessary inventory for goods with insufficient supply.

Cooperation with suppliers: Strengthen contact with suppliers, understand their production and inventory status, regard them as upstream stations during the implementation of JIT, and manage them in accordance with JIT requirements.

Simulated Kanban control within the company: According to the business process chart, each department of the company is regarded as different workstations, and a business contact form is established according to the relationship between upstream and downstream workstations. Business personnel will write down the work and time requirements that require cooperation from other departments on the contact form to hand over to the upstream station, so that all departments of the company can organically contact the business.

After the implementation of this method in a foreign trade enterprise in the chemical industry, it achieved good results, improved the management level of the enterprise, shortened the quotation and delivery time, strengthened customer awareness, improved service quality, strengthened internal contacts of the enterprise, reduced costs, improved business processing process, and formed a Team spirit.