VSM
Value Stream Mapping (Value Stream Mapping, VSM) Toyota Lean Manufacturing (Lean Manufacturing) under the framework of the production system is used to describe the logistics and information flow visualization tools. VSM can serve as managers, engineers, manufacturing personnel, process planners, suppliers, and customers find waste, looking for a waste of the root causes of the starting point. From this point, VSM is a communication tool. However, VSM is often used as a strategic tool for change management tools. VSM vividly describes the logistics and information flow in the production process, to achieve the purpose of the above tools. From the moment of purchase of raw materials, VSM start working, it runs through all process steps in manufacturing, warehousing leave until the end products.
Introduction to Value Stream Mapping
Value Stream Mapping (Value Stream Mapping, VSM) using lean manufacturing tools and techniques to help companies understand and streamline production processes. The object of the value of the flowchart in order to identify and reduce waste in the production process. Waste here is defined as any activity not be able to provide value-added end products, and is often used to illustrate the total reduction in the production process "waste".
Value Stream Mapping
VSM cycle time of the manufacturing process, when the time machine in process inventory, raw materials flow, information flow tracing and recording, to help visualize the active state of the current process, and is conducive to the production process guidance toward idealized direction.
VSM usually include tracing the "current state" and "future state" status, as the basis of the lean manufacturing strategy.
Value Stream Mapping (VSM) analysis of the two processes: the first one is the information (intelligence) process, that is, from the marketing department received customer orders or market forecast customer demand has begun to make it into a procurement plan and production plan the process; physical processes that start from suppliers for raw material storage, a library then the manufacturing process, product storage products out of the library, until the hands of customers served. In addition, physical processes, including product inspection, parking and other sectors.
The enterprises in Value Stream Mapping (VSM) analysis, first of all to pick out a typical product as in-depth investigation and analysis of the object, to draw out the diagram of information (intelligence) processes and physical processes of the status quo, then the status quo map information (intelligence) compared ideal condition map and physical processes, found that the problems existing in the current organization of the production process, and thus improvement measures are proposed to tackle the problem point.
Flow chart of historical value
In the 1980s, Toyota's chief engineer, Taiichi Ohno sensei Shigeo Shingo, the first use of place for production wasteful method to obtain a competitive advantage, their starting point is to improve production efficiency, rather than to improve product quality. The reason for this is because they believe that productivity gains will help lean manufacturing, to be able to expose deep waste problem in the system and quality issues. Therefore initiated a systematic attack on the waste problem is, the underlying causes of the quality problems attack to attack the fundamental management issues. Identified seven common waste of the Toyota Production System (parentheses Jones representation):
Value Stream Mapping
1. Overproduction (faster than the speed necessary);
2. Wait;
3. Transport (Handling);
4. Improper processes;
5. Unnecessary inventory (excess inventory);
6. Unnecessary action;
7. Defective (correct mistakes).
Value Stream Mapping seven tools
1. Process activity diagrams (Process Activity Mapping). Origin: industrial engineering.
2. Supply Chain reaction matrix (Supply Chain Response Matrix). The origins: Time Acceleration and logistics.
3. Production diversity funnel (Production Variety Funnel) Origin: operations management.
4. Mass filter Figure (Quality Filter Mapping).
5. Needs expand Figure (Demand Amplification Mapping). Origin: system dynamics.
6. Decision Point (Decision Point Analysis). Origin: Efficient Consumer Response / Logistics.
7. Physical structure diagram (Physical Structure Mapping).
Value Stream Mapping (VSM) analysis
Shorten the production cycle of the product is the key to quickly adapt to market demand, Value Stream Mapping (VSM) analysis method is the effective tool for the production cycle. VSM (Value Stream Mapping, Value Stream Mapping) analysis method was born in the mid-1990s, the United States, is an energy system to improve information (intelligence) processes, the methods of physical processes.
VSM analysis of the two processes
Value Stream Mapping (VSM) analysis of the two processes:
The first is the flow of information (intelligence), from the marketing department received customer orders or market forecast customer demand has begun to process into the procurement plan and production plan;
The second is the physical processes that start from suppliers for raw material storage, followed by the manufacture of the library, finished product storage, a library, until the products are delivered to the customer's hands in the process. In addition, physical processes, including product inspection, parking and other sectors.
The enterprises in Value Stream Mapping (VSM) analysis, first of all to pick out a typical product as in-depth investigation and analysis of the object, to draw out the diagram of information (intelligence) processes and physical processes of the status quo, then the status quo map information (intelligence) compared ideal condition map and physical processes, found that the problems existing in the current organization of the production process, and thus improvement measures are proposed to tackle the problem point.
VSM analysis objects: a waste
VSM analysis thrust is immediately exposed to the presence of the waste problem, and to exclude completely wasted. The reason why only identify the problem, in order to improve, many are not familiar with lean manufacturing will encounter a lot of problems, because they did not find the problem point. Therefore, to improve the waste in the production process of the business organization, we must first recognize wasted.
What a waste of JIT production, meaning wasted commonly referred to as a waste differ. For JIT speaking, beyond any increase part of the value of the product of the absolute necessary minimum amount of materials, equipment, manpower, space and time are wasted. Therefore, the waste of not only refers to the non-value added activities, activities also include the resources used for more than "absolute minimum" boundaries. Which the boundaries of "absolute minimum" With the gradual improvement of the enterprise management level, is declining.
2 value stream analysis focuses on eight wasted
Value stream analysis focuses on eight waste including: adverse / repair the waste of over-processing waste, the waste of the action, handling the waste, the waste of inventory, manufacturing excessive / premature waste, waiting for a waste management waste. These wasted are contrary to the JIT production. Eight wasted not after VSM, Toyota enterprises as early as in the 1960s proposed the concept. Which the management of the waste until the 90s of the last century really get people's attention.
Lean production management focus and goal orientation
The focus of the Lean Production Management
The focus of one of the lean production management is to create value, not value, but consume enterprise resource business process areas (Intelligence), physical delete all process areas. To find the problem by addressing the phenomenon of repetition, pause, and maximize the value of the management process. Therefore, the implementation of JIT to the value of the focus on innovation activities.
Another focus of the lean production management is to shorten the time. Shorten the time from market demand until production planning, procurement planning, the organization of production, warehousing, and manufacturing and finished products shipped L / T is shortened, thereby reducing the cost and increase the reaction rate. Therefore, in the case of increased resources, in order to shorten the information / operating time is the focus of improvement, looking for a fast way to complete the business and production to shorten the L / T as improving the driving force of change.
Goal orientation of Lean Production Management
The goal of lean production management orientation that is constantly set higher goals in order to reach a. As shown, were concerned about the production of lean production organization
Goal orientation of Lean Production Management
The process time and the value of the loss of the abscissa and ordinate, visible, the high value of the loss of the old process, the process of the production organization a long time, and the time and value of the new organization of production processes loss has greatly reduced. Lean production management to solve the problem is how to create value and to shorten the time. Improvement activities should be used to guide the day-to-day operations of the enterprise, the time, the loss is small, the next time is shorter, loss smaller as continuing management objectives.
Value flowchart application of common errors
1. Chosen the wrong track objects
The procedures do value stream mapping, select the object tracking product or service. Assuming he is a product, process flow and observe what changes in shape, function, packaging will. In the general manufacturing process, as the physical form of raw materials, semi-finished and finished products are still relatively clear, not prone to error. Services or administrative office environment, and sometimes it will make mistakes. Because in some aspects of the service industry environment, people will leave or transfer, the "product" has actually happened to change or transfer, but we will still adhere to the track of the original object.
2. on paper
No actual products or services go on to do value stream mapping. Sometimes not always production, or happen to be the most recent production, or the production cycle is too long, but the need to analyze the value stream (sometimes pressure from customers, sometimes the pressure from management). So someone does not "see" the case, relying on existing operating data and engineering standards (for example, data provided by the production department or IE department) completed a value stream mapping. What is more, this calculation a project made by the so-called "income"! They have forgotten some of the basic principles of lean production. First, if there is no actual inspection process inventory, they actually get is the flowchart (Process Map), instead of the value stream map. Secondly, there is no observed value flow diagram of the time measurement is how to, all of them can not be determined which the presence of waste, and improvement opportunities. Furthermore, the value of the stream behind closed doors is often ignored by some of the details of the actual operation, with the actual differences in the operation will lead to front-line operators are very confused, lost due guiding value.
Value stream mapping, I suggest to have done at least once a month in order to observe the actual situation in the different cases, and for comparison
3. hearsay
It is somewhat similar to the second point, is to stay in the office and no depth to the scene to observe the complete value stream mapping. I coached many businesses cadres, they are generally in middle management positions, and found that they often are less willing to practice in-depth. The widespread use of computers today, a lot of data will be stored in the computer. Depicts the value stream map, some people do not want to go deep into the workshop first line to observe, and would rather stay in the office call the computer data (such as stocks). Another case is like listening to others to provide field data (for example, called subordinates to find data, and then come back to report), but the data itself unconfirmed, with a great deal of difference. From a technical point of view, some data can be obtained from the data files or computer storage, the general flowchart patchwork. For example, a process the number of processes, the number of operating workers, warehouse inventory workshop layout, walking distance.
Technically correct does not mean that the actual situation is also true, in fact the situation may be very different. People do value stream mapping depth workshop site, mean the loss of a lot of wasted observed.
4. Double counting time.
In when the observed ready to fill into the data frame (information box), be sure to carefully consider what process steps, what should be put into the data box, and what should not. Such as the occurrence of the change over time (Changeover time), we all know to put into the data frame, because the books are about this. There are people still do not understand why is not listed separately, the lead time (Lead time) on a separate record. Walking another example, suppose spent 15 minutes walking time between the two processes, it is not on the value stream map should be a separate draw a data frame? Mentioned earlier, the two time not flow processing time? Do not put the data frame?
The key here is resulting in inventory accumulation causes and process of the actual product or service should leave, should not be confused. Inventory accumulation, as cited above, is too long breaks and walking distance, often resulting in the process somewhere / post inventory of the various forms of enterprises are, in fact, we have implemented lean manufacturing to eliminate . This is not a real process of the products or services. When we check the inventory actually put these factors include production lead time (Lead time).
Value stream mapping analysis clearly what is the reason for the backlog of inventory, what is the actual process steps of the processing of the product or service.
5. Ignore the shared resources
In many cases, the flow in the existence of shared resources. Shared resources is support / service more than one product family resources, there may be people, it may be the entire assembly production line, there may be a machine. For example, an injection is mainly the production of mobile phones and MP3 painting workshop in a machine dedicated to all the small parts spray, these small pieces of products including mobile phones, MP3 gadgets. Transceiver area of the warehouse, a wide variety of goods and raw materials have been here to do receiving or sending processing. In the above two examples, spraying machines and receiving area belong to the shared resources, further comprising where employees. If you forget them, it is easy to draw the wrong conclusions.
Transceiver to the above area for a simple comparison, it is assumed that the region to provide services to the two heavy-duty workshop, each the shop average daily production of 80 products, and received a total of 160 a day, on average receive 20 per hour , workshop 10 each. If a transceiver member of one hour to complete the work of 10, there is a clear need the two transceivers members work in this post. If the error in the value stream mapping to calculate the workload of a product family, it will give the impression that only one person in this role. Perhaps this example is too simple, but when you are faced with many of the hundreds of products in the product family, an error may occur, missed or ignored some of the product family. So be sure to pay attention to is not a shared resource.
Please remember correctly identify shared resources, otherwise it will lead to some important calculation error, such as takt time and cycle time will miscalculate.
6. Product family (series) confused.
Marking enterprise value stream mapping submit, I sometimes found on the main value stream mapping, a small value stream and out, it looks very complicated, and increase the difficulty of the analysis. The occurrence of this problem is that the analysis did not do a good job before the start diagram analysis product family. Some product family is very evident, for example, the different models of television sets, microwave ovens, refrigerators and other home appliances production, to see that; others not obvious, such as electronic parts production enterprises, the product of hundreds, even over thousands similar types of products, complex product manufacturing processes, ranging from more than a dozen road, many dozens, including many of the branch and confluence. Is generally believed that the study of process treatment process to achieve more than 80% of the same can be sentenced for the same product family. During the analysis, if there is no good in the identification process of shared resources, but also do not have a good track usually appropriate product or the flow value stream map is very complex, and can not reflect the real situation of the product family, even in farther and farther on the wrong path.