Today's short note: Exploration of the operation instruction manual in a sunny mood
Today, the weather is sunny. The sunlight pours down unreservedly, illuminating the whole world brightly. My mood is just like this weather, full of joy. This kind of pleasure stems from an in - depth discussion about standardized operations in the late night the day before yesterday.
That night, the production site became quiet, and everything was resting in an orderly manner. I seized this rare opportunity to consult a team leader about the relevant knowledge of standardized operations. In the past, I was not completely ignorant of standardized operations, but my understanding was not detailed enough and only remained at a general level. Standing in the huge production workshop and looking at the compact and orderly arrangement, I often felt confused. I was full of admiration for the wisdom in organizing production and also ashamed of my own shallow knowledge.
After a thorough conversation with the squad leader, I more profoundly realized my own ignorance. The squad leader's words are like a bright lighthouse, which made me understand that I can't be divorced from the actual situation at the site. The site is the treasure trove for obtaining answers. This also strengthened my determination to deeply learn standardized operations.
Next, I'll have a detailed chat with you about the specific steps for preparing the standardized work instruction (WI).
I. Accurately determine the workstation name
To determine the names of workstations, one needs to start with the assembly line in the workshop. Based on the actual requirements of the work and combined with past experience, the entire assembly line should be reasonably divided into different sections. This is like planning a highway, where different road sections need to be set according to the driving needs and destinations.
It is also crucial to determine the length and time of each workstation. We can calculate based on the total length of the assembly line and the estimated number of workstations. For example, if the total length of the assembly line is 100 meters and it is expected to install twenty components, then the interval length for each component is approximately 5 meters. If the line speed of the production line is further adjusted to 5 meters per minute, then the installation time for each workstation should theoretically not exceed 1 minute.
After determining the length of the workstations, it is also necessary to arrange the materials reasonably. Taking the material rack as an example, the storage positions of materials should be scientifically arranged within the specified distance of 5 meters to ensure the convenience of operation. Finally, according to the specific requirements of the process, assign an accurate name to each workstation, just like giving each child a suitable name, so that the workstations have clear identity labels.
II. Determine the action elements meticulously
In a workstation, it is crucial to accurately identify the action elements. These elements are usually distinguished by walking time. We need to list each action element in detail.
Assume that the above assembly line has 60 components and is divided into 20 workstations. Then, a simple calculation shows that each workstation is responsible for 3 components. When compiling the work instruction manual, the action elements of these three components need to be carefully distinguished. Generally speaking, the operation process of each component includes steps such as material picking, assembly, and inspection. These actions need to be repeated for different materials. It's like a well - choreographed dance, where each movement has its specific sequence and meaning.
III. Scientifically determine the assembly time
Determining the assembly time needs to be based on the motion elements determined in the previous step. However, this time cannot be determined by mere imagination but should be obtained through actual operations. Actual operations are like a precise ruler that can measure the approximate time required for assembly at each workstation.
With these time data, we can optimize and adjust the production line. For example, it takes 30 seconds to assemble three parts at Station I, while it takes 80 seconds to assemble the same number of parts at Station II. At this time, we can try to move some materials from Station II to Station I for installation, so as to balance the overall time of the production line and improve production efficiency.
IV. Comprehensively summarize all types of time
It is an essential step to the value-added time, non-value-added time, and walking time of each workstation. The value-added time refers to the time spent on changing the characteristics of materials, which is the part that truly creates value in the production process; the non-value-added time is the time consumed without changing the characteristics of materials, and this part of time can often be optimized.statistically analyze countstatistically analyzeIt is an essential step to statistically analyze the value-added time, non-value-added time, and walking time of each workstation. The value-added time refers to the time spent on changing the characteristics of materials, which is the part that truly creates value in the production process; the non-value-added time is the time consumed without changing the characteristics of materials, and this part of time can often be optimized.
We need to re - allocate time based on the statistical results. The goal is to shorten non - value - added time and walking time. Just like tidying up a room, we should clear out those useless sundries to make the room neater and more orderly, and the production process will thus become more efficient.
V. Carefully formulate the position-frequency diagram
In the position-frequency diagram, "frequency" represents the frequency, and "position" represents the location. On the work instruction sheet, we need to draw the shape of the material and divide it into several areas. Through specific markings, clearly define the assembly position of the material during assembly and the installation frequency at that position.
Normally, the frequency is consistent with the action elements. Taking the installation of buckles on a certain flat plate as an example, there may be three operations in Area A, two operations in Area B, and one operation in Area C. When compiling the position-frequency diagram, these information should be clearly marked on the work instruction sheet, and the number of operations of each workstation in each area should be clearly specified. In this way, operators can clearly know the specific requirements of each action and avoid operational errors.
VI. Carefully draw a mobile sketch
The movement sketch is a bit like a process flowchart, which can intuitively show the action elements determined in the first step. Although the drawing process is relatively complex and needs to be carefully completed step by step, once it is successfully drawn, the entire operation process will be clear at a glance. It is like a map, guiding the operators forward and enabling them to clearly know the sequence and positional relationship of each action.
VII. Clearly draw a periodic schedule
The last step is to draw a cycle time schedule. We need to clearly represent the value-added time, non-value-added time, and walking time statistically analyzed earlier in different colors and mark the specific time of each stage. Through this schedule, we can intuitively identify the value-added and non-value-added time, and then make targeted adjustments to shorten the manufacturing cycle and improve production efficiency.
The process of compiling standardized work instructions is indeed complex, but each step is of great significance. Even if the work instructions may not mark all the content in detail, all these contents should be fully considered during the compilation process. I don't have a deep enough understanding of lean production. I wonder if operating according to such work instructions can meet the requirements of lean production. This requires me to keep exploring in future study and practice.