A post-Corona, field-driven system – The Kanban Method and Scheduler

2020/06/23

インドネシアでのオンラインとリアルの融合を意識したビジネス体験

Introduction.

[Yamamoto]

So, ladies and gentlemen, thank you for taking the time out of your busy schedule to join our webinar today! . My name is Yamamoto from PT.Bahtera Hisistem Indonesia.

Today's webinar is titled "A post-Corona, field-driven system" and I would like to propose an approach to production management after the corona epidemic that successfully combines the pull-type kanban system, which is good at adjusting production onsite, and the push-type scheduler, which issues production instructions based on demand.

This webinar is meant to be a study session for both parties, and we would like to continue the series in the future, and we would love to hear your frank opinions about things that are systematically possible, but not possible in the field.

If you have any questions, please send us a message using the Q&A button and we'll be happy to answer them at the end.

Introducing Asprova Corporation

[Yamamoto]

Today's speaker, Mr. Kamimura from Asprova, would you please give us a brief introduction of your company?

[Kamimura]

Yes, I live in Japan, but usually once a month or so in Indonesia, Thailand, Vietnam I used to travel to Malaysia, Singapore and other Asian countries on business, but now I'm teleworking. I'm working from home and I'm happy to join the webinar from home today. Now, about our company....

Introduction of PT.BAHTERA HISISTEM INDONESIA

[Kamimura]

Mr. Yamamoto from Bahtera, please introduce your company to us.

[Yamamoto]

Our company is a manufacturing systems company in Bekasi that does production management systems, MES systems and IoT implementation for the manufacturing industry.

I myself have been working on systems in Indonesia for more than 16 years and have more than 10 years of experience in implementing the production scheduler-Asprova in particular.

Currently, I am using our own development tool called Hanafirst to develop an execution management system that works with Asprova.

Changes on the manufacturing floor as a result of the Corona pandemic

[Kamimura]

So, Mr. Yamamoto, how do you think the manufacturing site for corona pandemic is changing?

[Yamamoto]

The number of automobiles produced in Indonesia in April fell by as much as 80% compared to the same month last year, and it will take a year or two for the country to produce the coronavirus vaccine, which will depend on fluctuating demand.

Also, some plants have begun to produce masks, shields, respirators, etc., different from their original products, and I think that the standardization of manufacturing processes is becoming more difficult.

Mr. Kamimura, in terms of systems, what kind of new problems do you think have emerged with the corona vortex?

[Kamimura]

That's right, the demand for shortages and excess inventory is increasing more than ever before.

If the demand fluctuations were predictable to some extent, we may have been able to respond to them based on the intuition of our experts, but for demand fluctuations that we have never experienced before, it may be difficult to respond to them using our experts' intuition alone.

In addition to the Corona, the supply of materials is interrupted due to natural disaster and other factors, and it seems that every year some sort of problem arises not only for the company itself but also for its suppliers.

In Indonesia, many plants are using the Kanban system, which is the Toyota production system, and many of these plants are using Toyota's Kanban system, but there may be some people in charge who are concerned about whether the Kanban system is working as well as it has in the past.

The situation on the factory floor is changing in some respects as follows.

  • With unprecedented changes in demand and the need to produce new products, it is becoming increasingly difficult to respond to this demand using only the intuition of conventional skilled workers.
  • If workers are unfamiliar with the project, progress is not constant, and a flexible response is required.
  • The Kanban has been one of the most effective means of production adjustment, but the prerequisites for its operation have been broken.

When demand changes greatly, it is difficult to equalize monthly production, and pull-type "Kanban" alone cannot be used.

However, with push-type production instructions, if the instructed quantity is produced unconditionally, the problem of "overproduction" will occur.

Therefore, I think that a hybrid production system is required, one that allows flexible production instructions for each process in accordance with demand changes, and another that prevents overproduction by adjusting the production of "Kanban" as an operation.

Example: Komatsu Seiki Works


【Kamimura】

The key to Corona pandemic is information sharing and collaboration.

As various information changes, which operations are affected by this information and whether it needs to be addressed immediately. I think we need indicators that can be judged objectively.

Although this is not the case of the corona vortex, this case also shows that the scope of the response will expand if it is recognized early.

Therefore, the system required today, with its high level of demand fluctuations, is one that requires early recognition and communication to the relevant departments. Isn't that a requirement?

Also, there have been recent news stories of secondary infection clusters in food plants in Germany and China, but there have been no other reports of the same. It may not be a personnel matter.

Unnecessary on-site adjustments should be avoided as much as possible, even at the factory, due to unnecessary measures to be able to split the three nectars, and For example, if a product is in short supply, we rush to the site to look for materials, or adjust the plan with the site many times by manpower and sea. I think we should reduce what we do.

For this reason, a system that can be adjusted without going to the site is changing from necessary to essential. For example, during the flooding in Thailand, each plant promoted its flood countermeasures in its BCP.

For example, during the flooding in Thailand, each plant appealed for flood countermeasures in their BCPs, and even in the corona vortex I believe that the BCP will be required to present a corona measure for the BCP.

【Case Point.】
<Request>

  • Improve planning accuracy for reliable supply of parts to manufacturers.
  • Respond in detail to urgent items, delivery date changes and quantity changes.
  • Eliminate gaps between purchasing, planning, manufacturing and sales departments to improve operational efficiency.

<Background>

  • They are rigid in their approach to express products, delivery schedule changes, and quantities that occur on a daily basis and do not match their actual business. There were problems such as.

<Task>

  • The introduction of performance input (POP) requires improved planning accuracy to close the "gap" between planning and production.
  • In the machine manufacturing department, we have to deal with a wide range of constraints, such as the availability of machines, over and under staffing, and differences in processes depending on the type of processing. It had to be addressed.

<Effect>

  • Daily plans and progress of items can now be shared between departments, and the planning, production control, and manufacturing departments The company is now able to check on progress from the standpoint of the sales department, etc.
  • A large monitor can be placed at the site and can be used for reference from various angles such as equipment, processes, parts, orders, etc. It's said that we have a lot of leeway.

<Results>

    • We have set a large amount of safety stock to ensure that there are no shortages, so we cannot drastically reduce inventory. By maintaining a constant inventory through coordination and by reducing the amount of coordination between people in different departments, each department has the freedom to It is said that the level of motivation has increased.

Flow of Kanban

[Yamamoto]

This is a general flow of Kanban system. A take-back box is replaced with a take-back kanban inserted in the box, and a certain number of take-back cards are stored in the kanban post. Kanban is replaced with a Kanban in progress that is inserted in a box in the assembly yard and the box is shipped After being taken to the assembly area and accumulating a certain number of Kanban in progress at the Kanban post, the assembly area will be opened. The flow is as follows.

In a lot production process such as molding, a certain amount of intermediate stock is stored in the storage area and the inventory is reduced to a minimum. By the way, it is a signal Kanban that provides work instructions for the molding area.

[Kamimura]

This is a general flow of the Kanban system, but in order to autonomously adjust the shortage of items on site, it is necessary to have a system in place that allows for the production of the products. The feature of this system is that there is no under-production or over-production.

Even in a plant that uses the Kanban system, when the front-end process is a molding or press process, the assembly and press work in the back-end process is not carried out. Because the tact time and lot size are very different from those of the processes, Asprova has been installed in the front-end process and is used for the production process. In some cases, production is carried out with MRP-based work instructions and only the post-processes are operated with the "Kanban system".

In addition, since there are many molding machines and presses, it is important to consider which equipment to use for production and how to reduce the number of steps. In addition, a plan for allocating equipment that takes into account manufacturing efficiency is also necessary, such as whether to use a "Kanban" or a "tumbler". I think there are some aspects of the instructions that cannot be issued.

Production of Kanban

[Yamamoto]

Yes, the Kanban method requires that the work time between processes be equalized and that the monthly Since the number of Kanban units is determined by production volume, daily demand fluctuations are assumed to be limited to fine tuning.

Therefore, it may depend on the plant, but at the present time, when the day-to-day demand fluctuations change significantly due to the corona pandemic, It's getting harder and harder for us to keep up with the same Kanban operations as before.

[Kamimura]

Yes, there are a few conditions for the introduction of the Kanban system.

  1. Repetitive production.
  2. Leveling of production items
  3. High and stable production yields
  4. Low demand fluctuations.
  5. Establish a store behind each process.
  6. The number of boxes should be as small as possible.

Since the kanban system is to produce only the required number of products, the number of boxes should normally be limited to Ideally, the ideal is to reduce the number of pieces, and ultimately to have one piece of equipment flowing through the machine, but the production speed of the machine and the work efficiency of the shop floor should be reduced. Considering this, the box size is set to a certain number of units.

However, in reality, productivity is not good in box unit production, so even if a Kanban is not in progress, it is still "Kanban". Many factories set local rules, such as producing only after a number of "bangs" have been accumulated.

The calculation of the number of Kanban units is becoming more and more difficult due to changes in demand. It may further complicate the operation if you even need to adjust the number of units in the backlog.

Scheduler Flow

[Yamamoto]

Mr. Kamimura, we have been talking about the challenges at the corona vortex production site, but with the scheduler What exactly will the operation be like?
[Kamimura]

Yes, the scheduler will issue the appropriate work orders to meet demand, as well as complete the work in the previous process. The work in the process is indicated in green to indicate that the process is ready to be started.

In addition, a yellow color is shown on the work that exceeds the maximum stock to stop the process, which is the same as the Kanban system. In addition, the system allows us to adjust the timing of production on site.

In addition, the status of the front-end and back-end processes are signaled so that we can know in advance what to produce next, which allows us to adjust the production timing at an early stage. preparation and batch production will also be expanded.

In addition, we are also able to transfer equipment in accordance with changes in demand and to change the order of work depending on the delivery status of materials in a timely manner. It can be adjusted to

[Yamamoto]

In the Kanban system, the number of Kanban sheets is often adjusted based on monthly demand, but It looks like a scheduler with an MRP function will be able to calculate the number of Kanban units according to demand changes ?

[Kamimura]

Yes, it is possible to calculate the number of Kanban sheets even with Asprova if you can equalize the demand on a monthly basis However, Kanban is not able to respond to day-to-day fluctuations in demand or to assess the impact of demand fluctuations on each department. This can be difficult.

In addition, some factories have multiple in-process kanban, take-back kanban, MRP work orders, etc. Some aspects of the system may be more complex because of operating with instructions.

Scheduler operation with a single sheet of instructions and automatically remove the Kanban in the situation of the previous and subsequent processes. It could be a simple operation if the instructions could also be managed.

Demand fluctuations and work orders (demonstrations)

[Yamamoto]

What happens to the scheduler when demand changes?

[Kamimura]

Yes, the system will automatically adjust the number of work orders if there is a simple difference in the number of shipments in response to demand fluctuations.

For example, if demand increases, additional work orders are added, and the additional work orders increase the load on the equipment and cause it to start work. If the date is delayed, work that used to be stopped by Max inventory will be green and can be started. The scheduler will update all relevant information.

Scheduler operates with a single set of instructions, so all the information is concentrated in one set of instructions and the information is stored in one place. Management can be centralized.

Equipment load leveling (demonstration)

[Yamamoto]

I think the biggest advantage of Asprova is that it levels the equipment load and allocates work to it, but So the Kanban system can't handle it.

[Kamimura]

Since the Kanban system is a method of operation in the field, whether or not it can actually be produced in advance is another matter. By the way, you have to make a decision, and I think the scheduler can fulfill that role. In fact, we can see if production is leveling off between processes in plants where Asprova has been implemented.

In fact, it's important to know whether or not production between processes is being equalized in the factory where Asprova has been installed, and whether or not the facility capacity is being used. before operating Kanban to determine whether there is enough or no need for overtime. There are also examples of scheduling in Asprova.

Eliminate delivery delays (demonstration)

[Yamamoto]

I see, I'm not so sure about the feasibility of the Kanban system, but I'm not so sure about the actual manufacturing site. So you're saying that verification is important?

[Kamimura]

Once in operation, the system will operate autonomously using the Kanban system, so production can be carried out without delay in advance to meet demand. To see if it is possible, you should use the scheduler to set up the conditions and then simulate.

As I mentioned in the previous chapter, in a process where there are dozens of molding machines and presses, there are many molds, jigs, and workers. There are many equipment constraints, such as the following, and a plan for allocating equipment is also necessary.

Work Instructions/ Bill of Materials Progress Instructions (Demonstration)

[Kamimura]

Green indicates that the previous process is complete, yellow indicates that the stock has been exceeded and is pending, and gray indicates that the previous process has not been completed. As in the case of "start work," we coordinate the start of work while checking the progress of the previous process and the subsequent process. You can do this.

No matter how much work-in-process inventory is adjusted in the plan, if there is a delay in the progress of the previous and subsequent processes, it cannot be controlled as planned.

Therefore, the work instructions are used to indicate to the work site the start of the previous process and the extent to which the work can be carried out in accordance with the actual results.

[Yamamoto]

I see, so you're giving instructions to ensure that the item does not exceed your max inventory based on actual performance.

[Kamimura]

Yes, but also, as I mentioned before, you can inquire about the work that can be done in your process upon completion of the previous process. Which of the local rules in "Kanban" is to be produced together (stay in the Kanban post) Before the Kanban is turned, you can decide at the stage of completion of the previous process whether you want to make a decision on the number of sheets to be produced (the number of Kanban pieces) or not.

As mentioned in the case study, the early detection of the process allows us to prepare in advance (promotion of external setup), to organize the work, and to make a decision on which work to do.

Reduce shortages and line stoppages, arrange materials and adjust inventory allowances (demonstration)

【Yamamoto】
We have talked about production up to this point, but in the case study at the beginning of this article, we discussed the importance of information sharing and Collaboration'' and 'Ability to objectively determine which operations are affected by the information and whether they need to be addressed immediately. 'We need indicators', but when demand fluctuations cause a shortage of materials, even if the 'kanban' comes around It's going to cause you to not be able to produce.

[Kamimura]

Yes, if the delivery date changes due to fluctuating demand, the draw with material inventory will need to change as well.

If you use inventory on express items, other operations will be affected, but which operations will be affected and have problems It is necessary to make timely decisions on whether or not to.

It is also necessary to reflect the rules of each plant, such as not transferring materials from important customers to express orders.

Appropriate purchasing plans, delivery changes, and arrangements at the point of demand and order (demonstration)

【Yamamoto】

There are various conditions for material quotations, which are also difficult to manage with Kanban alone. Right.

Also, due to the planning of a pile of fixed lead times in the MRP of production management, the actual timing of production It is very difficult to source materials for the same type of product, so a scheduler is needed.

Now, when demand changes, not only do materials have to be allocated, but purchases also change on a daily basis. How does the scheduler deal with the differences in ordering methods for different lead times?

[Kamimura]

Yes, purchase shortages are automatically generated by MRP, so which items are ordered and when You can determine if it is necessary.

In case of over-purchase, you can decide whether to change the quantity or not by displaying the inventory information at the end of the period on the purchase order. It is also possible to output a list of over-purchases. In addition, if you clear the flag of purchase that has already been ordered, you can recalculate it with Asprova and eliminate the over-purchase. It is also possible to purchase items with a short lead time.

In addition, for items with a short purchasing lead time, the scheduler can turn the MRP based on demand to plan purchases. but the type of material that has a long lead time and keeps some stock in the warehouse. Create a purchase plan at the point of order where the scheduler will place an order at a time when the inventory is below the MIN. It is.

Conclusion

That's all for the presentation, but if you have any questions, please click on the Q&A button and send us a message Could I have it, please?

We'll send you a link to the survey later, and we'd appreciate it if you could help us out.

With that, we will conclude today's webinar with this one. Thank you very much.