CHANGEOVER COSTS …

How many of you reading this know what your changeover costs are?
 
A survey in an FMCG company shows that probably less than 20% or so know how much a minute of changeover, or any other kind of downtime is worth. When we say “know” we do not mean a number that is basically pulled “out of the air” or even a value calculated by manufacturing or engineering. No, to be useful in planning and cost justification, the cost must be established by the Finance or Accounting Departments. Only if it comes from them is it “official”. Only if it comes from them will management accept it. Too many times people are seen trying to justify dollars spent with minutes saved. This is apples and oranges. Costs may only be justified by comparing dollars spent with dollars.
 
The cost of downtime can be calculated in various ways depending on the company’s fiscal philosophies and operational situation. Some may count just the cost of labor. Others may count the impact on output or capacity. Still others will look at impact on inventory. Most will look at a combination of these three. In addition to these tangible or quantifiable costs, there will be other, intangible costs. The biggest among these is likely to be the ability to provide the service levels your customers demand.
 
No matter how it is calculated, changeover is expensive. It is typically thousands and tens of thousands of dollars. Of those companies in which I know the “official” cost, the lowest we have seen is still over $2,000/hr. Even when it is only hundreds of dollars, it can still add up. E.g. One company that typically did 3  1-hour changeovers daily assumed a cost of $1,000/hr and was amazed to find that they were spending $750,000/yr on changeover.
 
(Three quarters of a million dollar$ does tend to open people’s eyes!)
 
So how much is changeover reduction worth? We also looked at it this way in the spreadsheet. For every minute that could be cut from the average changeover time, this company saved $12,500/yr.
 
I think that there are 3 reasons that many companies do not get serious about changeover.
 
First, there are still too many people out there who think like that it is impossible to make a serious dent in changeover so they do not see the point of going to a lot of effort to accomplish relatively little.
 
Second, they think that the monetary benefits of changeover are not significant. Even companies that make less than one changeover a day and consider their costs in the hundreds rather than the thousands are still spending fairly significant amounts of money over the course of the year.
 
Finally, they are afraid that in order to reduce changeover they will need to spend huge amounts of money. We all know that this is false. Significant reductions in changeover time can be had for little of no out of pocket expense. A great deal of reduction can be had from operation issues. Eliminate the time waiting for materials from the warehouse by having it staged ahead of time. Small things like fixed gauges, multiple photo-eyes, tool elimination can be done using in-plant resources and a few dollars from the maintenance budget. Even where capital expenditures are necessary, such as for custom change part racks, the total amounts compared to the dollars saved are peanuts. It is typically found that reductions of anywhere from 25-50% can be had for little or no capital cost.
 
We have to know our costs. It is the only way we will be able to justify a changeover reduction program. It is the only way that you will able to motivate the people who need to be involved: everyone.

SMED Implementation Step by Step

by Enrique Morar

http://www.leanexpertise.com/

From my point of view and 20+ years of experience, this has been by far the most productive and quick-results rendering tool of all the Toyota Production System arsenal.  

SMED or “Single Minute Exchange of Dies” created by Shigueo Shingo and his group, and inspired by the car races’ pit-teams is a very applicable strategy and the more we use it the more applications we will find for it.  

The purpose of SMED is to create more flexibility and reduce WIP (Work in Process) inventories that have many devastating effects.  

I will try to describe SMED here Step-By-Step. This information does not substitute for a professional consulting-training service that may help you implement in a shorter period of time and especially for the first project, give you more effective results. It is convenient to make everyone aware that in a SMED setup we will most of the time use the help of more associates than in the traditional mode, but for periods of time that will continuously get shorter, increasing machine uptime. 

OK let us get started… 

1. One important consideration in any Kaizen Event even for a minimal improvement project, is taking pictures of the current condition. I don’t know how many times I have used the “before and after” pictures to make the motivation contagious to other associates even if they did not participate in that particular project.  
2. Find a strategic location for a video camera so you can take a timed video recording of the current setup procedure. Start recording at the time of finishing the last piece of the previous run. Keep recording until the first acceptable piece of the new run is completed. Measure precisely the total machine downtime. If your video camera does not have time recording, no problem, have a stop watch started and show it in front of the camera once in a while.Educating time.  
   1. Now we will bring together all the actors of the setup including the operators of the equipment even if they did not intervene in the setup process. The team must be comprised of the machine operator(s) and if available, setup experts or maintenance technicians. Add to your team a couple of outsiders. Sometimes administrative people can be of great help. 

1. Now we will explain to them the basic principles of SMED: 
   Internal and External operations of the Setup.
    

    

   1.  Usually, in the traditional Setup processes, all kinds of operations start taking place only after the machine has stopped, and continue all the way until they are finished, then the machine is re-started and hopefully in the first few cycles the output is completely acceptable and in compliance with specs. That is when the setup can be declared “Finished”
   2. This is not acceptable in the Lean Manufacturing environment; therefore the SMED process was developed. We all understand that there are a good number of those operations that we could group as “Preparation”, meaning they can be performed even while the machine is still working on the ending run.
   3. Some examples of these preparation operations:

                         i.      Bringing all the tools and materials (rags, cleaner fluids, spatulas) that we may need to perform the setup, close to the machine

                        ii.      Having handy all new parts, components, dies, cutters, etc, that need to be installed for the next run.

                       iii.      Have all the team members who will intervene in the setup prepared and made aware of which actions each one will perform. In some cases of complex setups, a rehearsal is convenient. Even professional pit teams do that before each and every race.

                      iv.      Have the members of the team discuss and then write on flipchart pages in detail and best possible order each of those preparation operations, step by step. Use as many pages as needed. We want those to be easily read from every seat in the classroom.

1.  
   1. These preparation operations will be considered “External”, since they do not need for the machine  to stop in order to be performed. 

1.  
   1. Now, let us think of the operations that can and must be done only when the machine is out of service.

                            i.      Now have the team list all those operations in clear detail, step by step, on one or more new flipchart pages.

                           ii.      For now do not try to put any pressure to reduce times.

                          iii.      These operations will be called “Internal”

1.  
   1. Finally, we will go through the series of operations that can and should take place after the machine is ready to run, these can be clean-up the area, putting back in place the tools, parts, components that were removed. All these operations will be grouped as “After-Setup” and are also considered “External”, since the machine can be back in operation with the new run while they are performed.
   2. Just as in the two previous groups, have the team discuss and list in flipcharts these operations.

1. Make sure they all are having fun as they do all of the above. Now, if possible have some popcorn prepared to bring in for the next step:

1. Viewing of your video recording…

1.  
   1. This part of the workshop is critical as they all will be able to realize how much time they could have saved in downtime, especially now that they have learned about External and Internal Operations.
   2. Remember to prevent any criticism or bad comments against any individual. All problems are due to the system, not the person.
   3. Have the members decide how the next setup can be prepared and staged, if needed make marks on the floor to decide where the tools, materials, parts should be staged in advance to the new setup.
   4. Same thing about the parts and tools being removed, they must find an appropriate spot where to be put while the machine can get started.
   5. For c. and d. we have found appropriate to use carts. If heavy parts will be handled make sure the cart is strong and stable enough to assure safety for everyone.
   6. At this point we need to decide if some of the Internal Operations can be simplified, coordinated to be done by more than one person, even eliminated. Feel free to skip or Fast-Forward the video when no relevant observations can be done.

General Ideas, Tips, and Practices… 

Some times we will discover that there are more bolts and nuts than necessary. 

In Forming, Stamping, Cutting Presses one helpful strategy is to create “Common or Standard Plates” for all the die sets.  

These plates will all be the exact same size required by the biggest set of dies that enters the press. All the sets of dies will then be aligned and permanently mounted in those “Common or Standard Plates” which will have perfect rail guides, location pins, and/or stop sets in the press. Obviously this will let us drastically reduce the time spent in “adjustments and measurements” each time we change dies. The front side of these plates can be used to write information that will give us the reference of stroke adjustment and some other data that our team members feel they may need or find useful.  

Other very useful advice: if covers and protections are involved, think of possible simplification in their way to fit on the machine. Gravity is a good friend here; some covers can be hung in L or U shape hooks instead of bolts and nuts. Also many nuts can be replaced with wing-nuts. Analyze any component that is mounted with bolts and nuts, most of them can be replaced with creative alternatives. One very important thing to keep in mind: Never compromise with the improvements the safety of the people, the product, the machine, and the facility.

Quick disconnect fittings for air, water, oil, electric devices, are also an important factor for reduction. Also power tools may come handy. Try to eliminate multiple sizes of bolts and nuts, even if in some cases you may be using too strong or long a bolt. Same size bolts and nuts can be removed and replaced much faster.  

Pre-Mounting of some tools and other parts in fixtures or chassis that we can duplicate is very convenient. Pre assemblies are also a good alternative.  

6.   We are now ready to write our first optimized “Standard Work Sheet” for the setup. Review step by step all the 3 groups of operations: Preparation – Setup – Post Setup.

7.   Discuss with the team any changes in the sequence of operations that may be sensible and ease the operation.

8.   Make sure the three groups of operations are clearly separated in the Process Sheets. The people who have been doing the Setup in the past will help the other members of the team understand the purpose and method of each operation, and the team must discuss and agree on the sequence, and if necessary, the process.

9.   Rehearse the whole setup in the classroom with imaginary machine, tools, obstacles, etc. Assure that people are not in the way of each other. Have each one understand the importance of the minimal operation. In some cases we can have physical parts and tools for people to become familiar with them.

10. After a few rehearsals the team is ready to apply the new setup in Real World.

Notice: At this time we have discovered that Not All the participants will be working Hands-On in the Setup operations. Only the number of people who in the rehearsal showed to be necessary to do the job fluently without stumbling on each other. The rest of the participants are acute assessors and will be taking notes that will help us evaluate the effectiveness of the process. Also from these observations we may find the opportunity to make more improvements.

Hands ON – Go to the Gemba and Do It!  

On the Job Training Time…

 

 

11. Get ready for the next setup. Make sure everyone has the information, training, tools, materials, and parts they will need.

12. Bring them to the floor with enough time in advance and start the preparation operations.

13. Have the video camera ready for the “New” Setup without deleting the previous one. Start by recording the preparation stage; that time of course does not count in the Setup Downtime.

14. The Setup Downtime must be measured with precision.  

Pit Stop Time! Now every second counts…

Make sure power is off or machine is in “Setup Mode” and all supplies are under control: Flowing Raw Materials, Compressed air, Water, and any other. Internal Setup is now ON!

15. During the whole process, but especially in these “Internal Setup Operations”, you want to have the standard process sheet handy. One person (if you have more than you need to perform the different Internal Operations), should be following the process and reading the Standard Process Sheet to assure correct sequence; another person may be of help by observing safety measures. People doing new things can get into risky behaviors without noticing.

16. As soon as possible, produce the first part(s) of the new run until the part or product is acceptable. Stop counting the Setup Downtime. Re-Start the normal operation.

Post Setup External Operations

17. Make sure everything is completely finished, cleaned up, put everything in the right place before leaving the area.

18. When doine, register the end of the Setup. Notice: this is Not the Setup Downtime.

19. Having measured exactly the amount of machine downtime you are ready to prepare a report about the improvement achieved. It should typically be less than half the traditional Setup Time; in some exceptional cases you may be able to cut off up to 90% or more.

20. There is a possibility that many new opportunities for improvement show up when we review the first SMED – Setup. If there is time enough, try to put together one more SMED – Setup with at least some of those new improvements.

21. Some improvements will probably have to wait for changes on installations, parts and tools acquisitions, some fabrications and alterations. Set a future date to do a follow up SMED – Setup and keep everyone informed of the achievements, including top management of course. 

Time to Prepare Presentation

Produce a graph that shows: the difference between the before and after downtimes. Estimate the profit produced by the machine per minute or per cycle, multiply the saved downtime – [additional productive time] – by the number of setups the machine may have in a year.

Quantify in the final presentation the potential for savings and/or Increased Productivity. Emphasize how the faster setup can help serve customers promptly and avoid excess (Just in Case) WIP inventory. Credit every participant either for their individual initiatives or for the team achievements. Make sure participants are listed in one slide of the presentation in last name alphabetical order; have them verify the spelling of their names before the presentation to management.  

Install a billboard near the machine showing a picture of the team along with a description of the improvement achieved. 
Note: Billboards always need an owner who will make sure they are kept up to date.

Produce certificates of participation thanking each of them for their contribution to the success of the event and encourage continuous contributions in the future.  

At the time of presenting the best way is to have the participants present the information to management, even if it is all in your PowerPoint presentation.  

The coordinator must keep following up on the teams to assure that the setups continue to shorten.

LEAN Trong Ngành Công Nghiệp Sản Xuất Hàng Tiêu Dùng

Bài viết này hy vọng mang lại cho đọc giả một ví dụ cụ thể về một dự án Lean tại một nhà máy sản xuất hàng tiêu dùng tại Mỹ. Có lẽ đọc giả cũng đã biết rằng, một trong những đặc điểm chính của nền công nghiệp sản xuất hàng tiêu dùng là sản xuất số lượng lớn với giá thành thấp nhưng vẫn phải đảm bảo chất lượng. Là một nhà máy được chọn làm “hoa tiêu” cho cả tập đoàn, nhóm dự án Lean đã xác định rằng một trong các tiêu phí lớn nhất hiện nay là lượng tồn kho quá lớn. Lý do chính cho lượng tồn kho lớn này, ngoài việc có nhiều loại sản phẩm, khối sản xuất luôn mong muốn có chu kỳ sản xuất thật dài nhằm giảm thiểu tỷ lệ ngừng máy và hao phí cho mỗi đợt chạy.

Khi đặt ra mục tiêu giảm chu kỳ sản xuất trung bình từ 7 ngày, cho tất cả sản phẩm như hiện nay, còn 3.5 ngày vào cuối quý 2, ước lượng số tiền “tiết kiệm” được sẽ tương đương 4 triệu USD. Để có thể đạt được con số rất đáng kể này, số lượng đổi sản phẩm trung bình từ hơn 80 lần trong một tháng sẽ trở thành gần 400 lần, tức hơn 10 chuyển đổi trong một ngày! Với số lần đổi sản phẩm như thế này, mỗi phút ngừng máy cho cho một lần chuyển đổi, mỗi sản phẩm lỗi được sản xuất ra khi khởi động lại máy và cả việc duy trì tốc độ máy thấp trước khi tăng dần đến tốc độ mong muốn, … đều trở nên rất quan trọng. Điều này dẫn đến một yêu cầu bức bách cho khối sản xuất là làm sao phải thực hiện chuyển đổi thật nhanh và hiệu quả: thời gian ngừng máy ngắn, sản phẩm lỗi trong quá trình khởi động thấp và quy trình tăng tốc sau khởi động thật nhanh.

Bên cạnh chương trình quản lý thông số vận hành truyền thống, cả khối sản xuất đã được trang bị thật nhiều kiến thức và kỹ năng cho SMED – Single Minute Exchange of Die, hay còn gọi là Quick ChangeOver – chuyển đổi sản phẩm nhanh. Với các kỹ năng được trang bị cùng với hệ thống phát huy sáng kiến cải tiến, rất nhiều thao tác chuyển đổi sản phẩm đã được rút ngắn đi nhiều lần. Điển hình là bộ phần đóng thùng, thời gian chuyển đổi hiện nay chỉ còn 5 phút thay vì hơn 30 phút trước kia. Các khái niệm của 5S cũng được vận dụng triệt để trong việc sắp đặt vị trí các dụng cụ, phụ tùng và tài liệu cho việc chuyển đổi… Tất cả đã tạo nên một dự án Lean thành công, giúp nhà máy nâng cao vị thế cạnh trang với giá thành thấp nhưng vẫn bảo đảm chất lượng vượt trội.

Hình trên là  một vVí dụ về việc rút ngắn thời gian tìm tihiết bị: những thiết bị thường xuyên sử dụng được đặt tại nơi sản xuất.