“Whenever there is a product for a customer, there is a value stream. The challenge lies in seeing it.”

-Learning to See, Lean Enterprise Institute

Since starting our series on value stream mapping we have discussed what a value stream is and how to identify the product or products to initially focus our VSM efforts on. To read about these topics in more detail please follow the links below.

In this third installment we will discuss how to go about creating a current state value stream map.

**It is what it is**

The key to creating an excellent current state VSM is to document what you actually see with your own eyes. We are not interested in how the process is supposed to work, or was designed to work.

Instead, we are interested in how the process is performing today. Will the process change a bit tomorrow? Sure. But that’s OK.

**Fun with Icons**

I remember the first time I saw a value stream map. I wondered how anyone could benefit from it. It was a bit messy, and I didn’t know what any of the little shapes and icons meant. In short, I was a bit intimidated by the whole experience.

Luckily, I had some great instructors and I did quite a bit of self study to get past my initial fears.

So, the only way you will not be a bit intimidated (assuming you have never seen a VSM before that is) is to study a bit and practice, practice, practice. There are really only a hand-full of icons you will always use. And for the rest, you can use a cheat sheet like I do!

**It’s time to create the map!**

OK, let’s learn how to create a current state value stream map. To help you visualize things I have created a fictitious example of a peanut butter and jelly sandwich factory.

Our PB&J manufacturing company goes by the name of KB&R Inc. For those interested, that’s the first letter of each of my three kid’s names!

**Step 1: Calculate takt time.** Don’t proceed until this step is done. If you don’t remember how to calculate takt time this **free resource** should help you along.

In our example, we have a daily demand of **700 pieces** with the following arrangement.

- Hours per shift: 8
- Break minutes per shift: 30
- Shifts per day: 1
- Days per week: 5

I recommend you practice punching this out. But in case you don’t, I’ll tell you the takt time is 39 seconds per piece. In other words, we need to produce a completed PB&J sandwich every 39 seconds in order to satisfy customer demand.

**Step 2: Get a pencil and BIG eraser.** The best value stream maps have eraser marks all over them. Please, I beg you; don’t use a pen when drawing these.

**Step 3: Have a big piece of paper ready.** Your standard 8.5”x11” piece of paper won’t cut it. Personally, I prefer the 11”x17” paper size. It’s big, but not too big to carry around.

Finally, while I will be drawing the value stream map using software in this article, I recommend you always draw the map on paper first. Then, when you are ready to share your masterpiece with senior management you may choose to go for the software.

**Step 4: Walk the process front to back.** Quickly walk the process with your team in order to understand the general flow. It’s important to also define the start and stop point of the process. Don’t attempt to take on too much. Remember, we eat an elephant one bite at a time.

**Step 5: Draw in the customer box / details.** In the top right hand side of the paper we draw the little saw topped box representing our customer.

We also note their monthly and/or daily demand along with the takt time as calculated in step 1. Click to enlarge the picture to see what this looks like.

**Step 6: Go to the end!** Next, we start at the END of the process and begin drawing the map back to front. And don’t forget about that eraser. You will need it. I recommend you nominate a scribe and have them draw the map for the team.

Another trick is to ask each person on the team to map it out so you can compare and consolidate when you get back to the room. Yet another trick is to have the team divide and conquer as you send some off to map the beginning section, some to the middle, and some to the end.

There are many ways to do this. Experiment and do what works best for your situation.

**Step 7: Focus on the material flow first.** Focus on the material flow side of things first (bottom portion of the map). This includes the process boxes and data boxes.

Regarding the data boxes, if you don’t have all the data perfectly collected on the day of the mapping exercise just do the best you can. You can always assign homework to go back and validate the figures later.

In fact, even if you think you have solid data, the six sigma side of me urges you to validate your measurement systems to make sure we can trust the data. If you want to get really tricky state both a measure of central tendency and dispersion. You won’t see this advice in most lean VSM books… I guarantee it!

After studying the KB&R manufacturing process for an afternoon we learned that each process step is staffed with 1 operator. We also collected cycle time information at each step. Additional “homework” will be to collect information such as defect rates and changeover times.

**Step 8: Add the Inventory/Wait Times.** Once you have all the process and data boxes in, it’s time to add in inventory and/or waiting times. These are the little yellow triangles with an “I” in the middle.

For inventory, we simply count the number of pieces in between the processes and note them under the triangle.

We also want to convert these pieces into days’ supply. To do this, we divide the number of pieces by the average daily demand (which we used to calculate takt time).

So, if your average daily demand is 10 pieces and you count 20 pieces of inventory in between process step A and process step B you have 2 days’ supply (20/10) in between the two processes. We will note this number on our timeline (to be added in a future step).

Lastly, don’t attempt to map every part number! Choose one or two key components to start with. You can always add more to the map later.

In our example, we chose to simply count two pieces of bread as one subassembly since they move together down the production line.

Also, we are not accounting for the peanut butter and jelly “raw material” at this point since KB&R’s expert supply chain team negotiated a killer consignment stock deal with Sam’s Club so this inventory is quite low on the line.

During the study, we learned that, as one example, there were 486 sub-assemblies (972 pieces of bread) in between the jelly application and packaging stations. This equates to 0.69 days’ supply (486 units / 700 daily demand).

Lastly, during the walk through of the process we noticed that each process step seemed to be working in isolation. In other words, the lady working at the peanut butter application seemed to produce as many units as she could and then pushed them along to the jelly application process.

This “push” process is found in just about every mass production process known to man kind. When we see this pushing action we note it on a VSM with a dashed line through the yellow inventory symbol.

**Step 9: Draw in the information flow.** This step is what really separates a VSM from traditional process maps in my opinion. You see, in addition to learning about how material flows we also want to understand how information flows.

For example, we want to know it is moves about electronically? If so, we use a lighting bolt looking arrowed line. Is it communicated manually? If so, we use a straight arrowed line.

During this step we also draw in our production control box. For many, this box will include the letters “MRP” in it. In most mass production systems we typically see several manual information (straight) lines coming out of the MRP box aimed straight at each process step box.

In our example, we learned that production schedules each process step in isolation. In other words, each work station gets its unique production schedule. We draw this using straight “manual” information lines.

We also add in the information flow from our customers as well as to our suppliers. In our example, we learned that PB&J’s customer sends 30 days electronic forecasts as well as electronic daily orders. Conversely, PB&J sends its bread supplier an electronic weekly forecast.

**Step 10: Add in the timeline.** We can now add the timeline to the bottom of the value stream map. This saw tooth looking line helps us separate the value added cycle time (taken from data boxes) from the non value added time (days’ or hours’ supply info).

The last step in the process is to sum up all the “value-add” cycle times and note them at the end of the timeline. Likewise, we also sum up the “inventory” times and note that on the timeline.

In our example, the total value add cycle time sums to 97 seconds and the total non value add “inventory” time sums to 2.39 days! We call the total inventory time the **production lead time** (PLT).

To calculate the process cycle efficiency (PCE) we divide the value-add time by the PLT. When we do this we get a PCE of 0.15%. To see exactly how this was done **please read this article**.

**Summary**

And that’s it my friends. You just created a current state value stream map. This may seem a bit daunting initially, but with just a little practice you will be a current state VSM drawing machine!

Up next, we will see what improvements we envision for this process as we draw up a future state value stream map. If you have a thought to share or question to ask please don’t hesitate to leave a comment below or **contact me**.

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**Keep Reading**

Read the next article in this series: **Let’s Create a Future State Value Stream Map!**

Ron, thank you so much for all this free information! I am amazed you don’t charge for this stuff. Most websites only offer cursory glances at topics. But you really dig into things. Thanks so much!

Why thank you, Alan. I truly appreciate your kind words. Please be sure to come back as I have lots more to share with you and everyone else. All the best my friend.

Instead of drawing it with pencil and paper, I’ve found that (especially with groups), post-it notes and a whiteboard can work very well. Draw your process steps onto post-its (you can even re-arrange them easily if need be) and draw arrows/connectors on the whiteboard. Then, take a digital picture of the map (if you’re going to then digitize it into Visio or some other software).

I’ll disagree, in a friendly way, that you can’t go through the mapping process without understanding takt. In many hospital environments, there’s no data on volumes or demand. That doesn’t mean you can’t go ahead and start observing, mapping, and kaizening the process anyway.

Great idea with the post it notes Mark. I have also seen people use pieces of paper that look like data boxes. This is great since you can write done the key metrics on the paper.

I take your point on takt. However, I will say that I have heard “we can’t calculate takt” so many times… even in highly engineered “job shop” type environments.

But after some questioning and digging in these same people came to realize they too could calculate takt. Now was it as straight forward as in this example? No. But it can be done.

Have I done this in a hospital? Nope. But I’d sure love to take a crack at it one day!

Right…. I hear what you’re saying. But, I’d maybe come back and look at takt *after* doing the VSM, rather than letting it be a roadblock

I’ve seen (but never used) post-it pads that were especially made for VSMs (had the data box fields pre-printed). Me, I just use plain post-its.

thanks Ron, but how could we calculate the TAKT time in an front office Process?

Great VSM. Just a silly question but is the waiting time measured when walking the process or was there a calculation applied to determine the waiting time for each step?

Hi Jarod, in this example the waiting time is actually “inventory time” meaning we converted the inventory into days of supply.

From the text above:

We also want to convert these pieces into days’ supply. To do this, we divide the number of pieces by the average daily demand (which we used to calculate takt time).

So, if your average daily demand is 10 pieces and you count 20 pieces of inventory in between process step A and process step B you have 2 days’ supply (20/10) in between the two processes. We will note this number on our timeline (to be added in a future step).

Hi Ron,

First of all, thank you for the info you’ve posted about the VSM, but I’m still facing some issues regarding the way you calculate the “inventory time”.

For instance, if you have 2 different types of pieces waiting before a process, would you consider it like only one type (for the total number of pieces waiting there) considering the fact that you’ll need both in another process as “assembly”?

Also, same case : you have for example, 2 types of pieces that go through the same process but the operation done is not the same, how do you represent it on the VSM ( 2 process boxes ?) and also how do you calculate the “value add time” (C/T(1) + C/T(2)) ?

I hope i’ve been clear enough and thanks you in advance for your answer.

Thank you very much for your clear explanation on how to make a VSM. I have to make one for a presentation I have within two days. Your explanation has help me to get a better understanding on how to do it.

Our company, Grand River Rubber, is in the process of implementing a 6S program (the 6th S is for safety). Although we already implement lean strategies we are constantly looking for ways to improve our processes. As a newer Lead Supervisor with very little Assistant Supervisor experience I am very interested in VSM. I found your articles to be very informative and well laid out. I can’t wait to create my own VSM. Thank you much. This kind of information can’t be found anywhere else for free.

A few comments:

1) The calculation of the inventory time, should not be done on a one-time manual count, but should be done by calculating average for a day. In the first inventory (700 pieces) the inventory time would not be one day if you do an average. The peanut butter application is 25 sec. meaning 144 pieces an hour. Then it follows: eg. 700 hour 0, 556 (700-144) hour 1, 412 (556-144) hour 2 etc.. Then you end up with these values:

Hour Inventory

0 700

1 556

2 412

3 268

4 124

5 0

6 0

7 0

8 0

So, we add the values (700+556+412+etc.) and then divide it with 8 (which is the total working day hours) then we get roughly 258 pieces, which is closer to the real average inventory.

2) In one phrase you say that peanut woman ‘seemed to produce as many units as she could and then pushed them along to the jelly application process’. Later on you say that she is disciplined by an MRP…. thats contradictory.

3) We need information about shipping frequency in order to calculate inventory time of finished goods.

Thanks for the excellent comment, Kenneth!

Regarding inventory, there are indeed a number of ways to go about this and a lot of it will depend on your industry. Since VSM’s are dynamic we must always remember to be careful with thinking we’re ever “done” or “correct” since – even if you average things – inventory levels may vary dramatically a week later for a mass producer. The key is to get a snap shot of where we’re at, understand why we’re there, and then figure out how to improve the situation.

My point in mentioning MRP systems is that while she may have gotten a specific work order or requirement she will complete this work at her own pace, pushing it to the next process even if they are not ready for it. In other words, MRP systems often promote a “process island” mentality.

Yes, you’ve got a point. However, you calculate lead time to be app. 2,5 days. If we did a snap shot of the factory 5 minutes before closing time, we would probably have no raw material inventory and WIP would be lower. Then the lead time could easily be around 1 day instead of 2,5 days. That could have a strong argumentative impact against leaning the operations.

But I certainly agree, on fluctuations in general.

It is very clear it will be possible to include tips for example team work analisys for detect opportunities before creat future map?

It is really helpful material but I need more details regarding calculations of:

1. cycle time

2. defect rate

3. changeover time

I would ask if these information can be calculated as average over a period of time?

Regarding inventory levels, I agree with kenneth comment about the average but I think it is better to collect such data over a longer period (days) and then calculate the average inventory. what do you think?

Moreover, the wait time should include transportation time in order to reflect the layout of the factory (distances between sequencial processes).

Finally, the changeover time and other planned or unplanned stoppages (down times) do not appear in the timeline. how we consider it for improvement?

Hi there Ron,

Well i am no expert in VAMs but i intend to understand as much as i can. Now let’s say we had set up times for equipments and non-conformance of certain products. Where would that fit into in the current state VSM?

Mr O.A.U – Thanks for the question. You can, and should, note things like setup times, defect rates, etc. in the data boxes below each process step. If you’d like to learn a lot more about VSM please check out what we have to offer over at Gemba Academy (http://www.gembaacademy.com).

Hi, nice article, Ron, thanks!

Here is a short video showing the basic VSM idea:

http://www.youtube.com/watch?v=3mcMwlgUFjU

Haven’t found anything that gives this level of details anywhere else on the web. As a newbie your writings are tremendously useful. Thanks for putting it out. A silly question though. How did you arrive at the 0.15% PCE? Is it 97s over 2.39 days (converted in secs)? It does not seem to give me 0.15%. What am I missing? Thanks in advance.

With regards to Nader’s question, i also noticed that the PCE i obtained is somewhat different from 0.15%. The value added ratio has always been VAT/Lead Time. Your total lead time is 2.39 days and value added time is 97s. The PCE i obtained was 1.11%. Please could you help us clarify this misunderstanding.

Hi Nader and Mr O.A.U, rather than attempt to answer your questions in these comments… I decided to write a new article and post a short video explaining how the 0.15% PCE is calculated.

Please check it out at: http://blog.gembaacademy.com/2010/04/15/how-to-calculate-process-cycle-efficiency/ and let me know if you have any other questions.

Check out http://blog.gembaacademy.com/2010/04/15/how-to-calculate-process-cycle-efficiency/ for an explanation on how the PCE was calculated.

This Stuff is really very helpful with deatailed steps ………Thanks Mr Ron , the stuff provided by you is very helpful……………………..it will be more

This Stuff is really very helpful with deatailed steps ………Thanks Mr Ron , the stuff provided by you is very helpful……………………..it will be more

helpful if some examples are also provided parallely……………thankx Mr Ron

Hi Ron,

I am confused about the days of supply calculation in case of multiple operators. Should we use

Inventory / (tatk time * number of operators) since if the inventory is being processed by 2 operators it will get over faster (half the time) than if it was being used by 1 operator.

Hi Akshhay, the number of operators does not impact the days of supply calculation since all we are doing with the DOS calculation is dividing customer demand to the number of pieces of inventory on hand.

So, if we have a daily customer demand of 50 widgets… and we count 100 pieces of inventory between process 1 and process 2 we know we have 2 days of supply between those stations since 100/50 is 2.

Make sense?

I think I got it.

I was thinking of days of supply for the next process. Hence I thought that the inventory will deplete faster if there are more operators consuming the inventory.

BUT

Since the customer is only going to buy so much (through takt time), it doesn’t matter how many operators consume the inventory. The days of supply for the customer will remain the same.

Right?

Hi Akshay,

If you have to operators instead of one at one station, then the incoming inventory will everything equal be lowered. This will therefore decrease inventory days at that specific place of inventory. However, if the subsequent work station is/becomes a bottleneck then the inventory will instead pile up in front of that next work station.

The consequence and the morale is that total lead time will not go down if you dont elevate the bottleneck activity.

Friends can anyone help me for this doubt regarding VSM. Actually my company has 12 different part numbers. of those 6 part Nos. follows 10 operations, and within the 10 operations there is some cycle time changes for some part Nos. Suggest me whether I have to map all the 6 Part Nos by taking an average cycle time or I have to put 6 VSM for all the 6 different parts.

Hi Balaji,

That depends on the purpuse of your VSM. If you want to compare lead time between all part Nos. then you have to map all part nos. However, if you want to compare the 6 part nos. going through the 10 operations with the other 6 part nos. going through other operations, then you can settle with an average. Then you have grouped in product families.

But dont forget that a VSM has a lot of limitations. For example, it does poorly in visualizing monuments (operations that multiple part nos. share)

Thank you Sir for your response.

Now i came with a conclusion to map all the part numbers (i.e. 12 VSM’s ), So that i can derive different lead time for different part numbers and accordingly I can suggest the inventory to be maintained between the work stations. Am I correct?

I want to join

I’m trying to implement vsm in the food production company I work for through self study, mainly using the internet. Your website and explanation is very helpful in this process! Thank you for that.

While collecting the first data for my current state map I’m confused by the different definitions of ‘C/O’ that I find on the internet. It is not really important for understanding vsm, but I want to understand completely in order to explain others correctly in the future.

C/O, to me, is likely to be ‘Change Over time’ which I would define as the time needed to change your machine settings in order to start producing a product from a different product group (for example this website: http://www.strategosinc.com/value-stream-mapping-3.htm confirms this thought).

In practice, and also in your example, I see the space tagged ‘C/O’ in the databox used for the time it takes one product to walk through the specific process linked to that databox.

It seems to me that the second definition is the one to use making the current state map. I just don’t see how this has anything to do with change over time.

I hope you can help me clarify this vsm-mystery.

Kind regards,

Joost

The Netherlands

Hi Joost, let’s assume we are talking about two products – A & B. In this case, the definition of a C/O is the total time between the last good A and the first good B. So the total time between this is in fact the C/O.

As it relates to VSM… we normally note this C/O time for that process as you suggest. One thing to keep in mind is that a VSM is only a snap shot of the process. There are other tools like the Process Capacity Table that can and should be used in harmony with VSMs.

As a small commercial (sorry) we do cover all of these topics (VSM, Changeover, Standard Work, and much more) in our Gemba Academy courses. You can register for a free trial account to get a flavor of what it’s all about at http://www.gembaacademy.com/amember/signup.php.

I hope this helps! Great question.

Hi Ron, thanks so much for your fast and helpfull reply. When I master the basics of lean I will consider signing up for one of the offered courses.

Thanks again,

Joost

Thanks Ron for how to start a value stream mapping.

I do have a doubt though.

Supposing if I have got a machining line that is shared for some 20 part numbers and I am going to plot the VSM for 4 part numbers, how do I go about calculating the takt time? Even if I calculate takt time for these 4 part numbers based upon customer demand, how do I correlate it with a VSM.

Do we need to factor in the time available at each machine for processing these part numbers?

Is my question clear?

Thanks in advance for the clarification.

Hi Nishant, your VSM should focus on Products. You should use the PQPR tool (see previous article on this) to help select the right Product line to focus on. You may also decide to start with the most expensive part number in that product to map assuming product flow for all part numbers in the product is similar.

Now, to be sure, shared equipment can be tricky… but, in the end, you need to do your very best to keep things simple with respect to calculating takt time.

Remember, Takt Time = Net Available Time / Average Daily Demand. So, if the factory is “in operation” for 480 minutes each day and the demand is 240 units… takt time will be 2 minutes per part. Don’t make that harder than it is and don’t attempt to massage the net available time based on what you believe to be availability of your equipment… otherwise you will lose your mind as that availability will constantly change.

If you are consistent when calculating takt time for every Product you produce you will quickly learn whether you have constraints (waste, not enough people, non capable equipment, etc.) within your system allowing you to identify countermeasures accordingly.

Thanks once again Ron.

Perhaps I should have elaborated.

As an example, assume that 4 part numbers run on a machine and I am mapping the VS for 1 part number whose takt time is 60s. In the data box, I specify the cycle time for machine is 20s. In the first glance it would seem that there is apparently no big problem with the cycle time as cycle time is 20s against a takt time of 60s for that particualr product. But on the contrary, if I map the process for all 4 part numbers, the takt time would come well below 20s, around 13s.

How to proceed in such a case?

I think you are confusing cycle time and takt time. Takt time is calculated and cycle time is measured.

So, in your example, I assume each “part number” is from a different product family, right? If so, then each of those products will have their own takt time that is calculated as follows: Available Time / Customer Demand. The available time has nothing to do with how many machines or people you have. It is simply the amount of time your company “keeps the lights on”. In other words, if a shift operates for 8 hours then 8 hours (480 minutes) is what you use in the takt time calculation for all products.

With this said, some companies do in fact manipulate their net available time based on the availability of shared equipment. Personally, I am not a big fan of this… but I have seen it work if the scheduling department is consistent.

So, in this case, let’s say your 4 different products have equal demand meaning in an 8 hour shift 2 hours would be dedicated to each product family using the same production line. In this case, takt time would be calculated as 2 hours (120 minutes) / customer demand. This is referred to as mixed model production and can be very complicated so care must be taken.

Hope this helps.

VSM was one of those fields i always lacked confidence. I tried a lot to dig in the net for Study material for VSM and found less informative ones mostly. But then I came across this page and must say that this was the most informative, easily understandable material I’ve ever come across. A big thanks to Ron for I am more confident when it comes to VSM now.

Dear Ron, thanks a lot for such and informative article. I am doing my project on VSM and other lean tools. Your all other articles are really useful for manufacturing management students like me

Hi Ron.

Thank you so much for the information!.

I have a doubt, when i am calculating the inventory time, i have to take as reference the takt time or the cycle time from the next operation?. Because the cycle time to the next operation is which define the rate of production for the previous inventory.

I hope that you can help me in this topic.

I´m working in a logistics company.

Best regards.

Fantastic work keep it up. I am currently doing a course in Lean Sigma Six and am currently using a VSM with a PFEP in a timber frame factory and have found this very useful.

all the best neil

Hi !!!

Initially i thought i will have to break my head for learning VSM

but the way you have presented it was like spoon feeding (which i think is the best way to learn and teach )

Thank you

Thank you Ron for this article.

I read it long time ago, but I reviseted recently and wanted to drop a line.

In my experience, I like to have a multidisciplinary team draw down a first draft of the VSM before “walking the process”. I find out very exciting when, in most cases, they discover that what they believe the process did, does not match 100% what the process actually does.

For this reason, I like to have the team draw the first VSM in a big piece of paper that we can take to the shopfloor. Once the team walks the process, we are ready to go bak to the war room and complete the VSM. This is specially useful for teams which have never drawn a VSM before as part of their training.

Regarding comments that Mark (Graban) mentioned about Takt, I will have to agree with him. But not because it cannot be calculated, but because I found out several times that some Senior Management believes on the power and need of VSM, but do not feel the same way about what actually Takt time represents. Therefore I have found most usefull to go ahead to VSM at first and calculate Takt and understand what it really means at the end, but always before attempting to start Future State.

Once again, great article. Thank you.

Hi Ron,

Thanks a ton for this detailed article on VSM. I have a doubt on calculating Takt Time when we have overlapping shifts.

For ex: In our company we run 3 shifts (7am-3pm), (12pm-9pm) & (9pm-7am). We have three shifts we three different working hours and first shift and second shift overlaps. In second shift we have more online orders coming in so we have more staff on the shop floor.

In such a scenario how do I calculate the Takt Time. You help is really appreciated.

Thanks

Suhas

Hi Suhas, takt time isn’t impacted by number of people. The only thing that matters is net available time and average demand. You can calculate takt every hour if you’d like or just average it out over an entire shift.

When you have more people available you can obviously produce more… but, again, when it comes to takt the number of available people or machines or whatever doesn’t impact the calculation.

With this said, in your case, you could adjust the “demand” figure for one shift during your takt calculations if you know you have more people available.

In the end, make the tool/concept work for you. Takt time simply helps us understand what the customer wants so we can set our processes up to meet them.

Make sense? Check out our Transforming your Value Streams course for much more info on this topic if you want to dig deeper:

http://www.gembaacademy.com/products/school_of_lean.html#transforming_your_value_streams

Hi Ron,

I really appreciate your effort in taking time and replying to the posts. Thanks!!

I was using the Takt Time calculator worksheet that you have provided in the article. As explained in my previous post our customer demand is about 1200 pcs a day (starting 7am-7am next day) in 3 shifts. Should I calculate Takt Time for 3 different shifts taking Customer Demand as 1200 pcs each shift. By doing this I received 3 diffrent Takt times 23secs, 20secs and 17secs for three different shifts. Should I take the average of these three and considered that as my actual Takt time?

Kind of lost, Please help!

Thanks for your reply.

Suhas

Hi Ron…

Im implementing VSM in foundry. But I’m confusing in loading and unloading time calculations. can we add this loading n unloading time in cycle time or in C/O ??

Hi Er. Vinayak, make the VSM work for you… the power of the map is in how it helps you see waste. So don’t worry so much about all the technicalities… make the tool work for you… not the other way around. So if it makes sense to you to add to C/O or C/T do it. Just be sure to explain what you did to your team so everyone is on the same page. Make sense?

Dear Ron,

I am becoming your fan on this site. appreciate your efforts in making these thing easier for people to apply.

I have been trying to use VSM in my process. I have trouble in understanding how to use VSM where I do not have exact pieces. I would like to state my process briefly, shall request you to please give some time to this much…

We produce a sort of glass wire continually in one process from one ingot (16 hours run). When one ingot finishes, process set up takes 4 hours. It runs in range of 200 km in one reel. Several such identical machines are in this process. These reels goes to another process where these are converted to smaller lengths say 15- 50 kms each. These small reel goes to testing and then for dispatch.

Only one product family of this wire with one variation that either it is sold in natural color or with colored (11 colors). Coloring is optional many times and most production goes natural.

The production is “make to stock” i.e. we just guess from market trend and for the month we take a target. currently it is full capacity.

I have started making VSM roughly and to arrive at product pieces, I take no. of reels (smaller which shall be shipped) on the basis of average length.

can you advise me what and how would be your approach in this case. I should share with a flow diagram to explain, if u give me your email, I can share that too.

Your guidance shall help me for sure.

Thank u very much for your precious time.

Hi!

I just finished my first CSM creation thanks to this article! One thing I’m pondering here still: Our product is a paper press product so in one sheet there are multiple units of product. At the same time there are several sheets involved into the finished goods. The thing that bothers me is that as we run the same sheet pass one machine several times I’m already a bit lost in calculations: should I include 1 sheet as a 1 product or count as 1 sheet containing several final products? This is also tricky in the sense that the cycle time calculation is based on either the cycle time divided by the number of products or the single cycle time. I’m struggling between two and probably ending up making 2 different versions just in case…

Hi Juho, you may want to consider calculating and using a metric called “pitch.” Pitch is derived as follows: take time x batch size. So, if your case, if your takt time is 30 seconds and each sheet has 4 “products” in it your pitch would be 120 seconds (30 x 4). This may make more sense then simply attempting to balance all your process cycle times to take… instead, you’d balance them to pitch. Make sense?

Thanks Ron! This was actually one of my thoughts, so yes it makes sense. Then I guess I would need to use the same multiplier to calculate the stocks as well. To recap this: no matter which way I choose I just need to keep it consistent through the line so whether or not it seems to make sense in some points I just need to keep up with the same idea.

…oh and about the cycle time: sometimes it’s mentioned to be the time that it takes for one product to run through a machine. In our case of course there are multiple products in the machine at the same time. This makes me wonder whether to measure the time it takes one product to run through the machine or the time between two consecutive products to come out of the machine. I think that the later here is something else… please correct me if I’m wrong!