Monday, October 31, 2011

Sometimes We Remove Technology

I consulted in a plant that had a large machine that cut rubber tubing into pre-determined lengths. Next to the machine, I spotted a large wire container with cut tubing lengths.  It was labeled with a red tag with the word REJECT visible from twenty feet away.  The detail on the tag revealed that the tubing contained in this container had been cut too short.  It was probably going to have to be scrapped.
I asked why the tubing had been cut too short.  Probably human error in setting the machine, I was told.  The specs were not entered correctly and no one noticed until a full container had been cut.  We formed a work group to find a way to prevent this problem from every happening again.
We discovered that the internal customers for these products were two assembly lines.  Tubing that was too long could easily be cut down to size.  Tubing that was too short could not be used because it did not reach the two points in the assembly that needed to be linked. 
We quickly came to the idea that the tubing was quite easy to cut, so why not cut it just-in-time.  The team designed a guillotine (actually a small paper cutter), mounted it on a bench with a channel and a stop that measured the tubing to the required length, making it easy to cut just one piece when it was needed.  The roll of tubing was too large to have on the assembly line.  We cut off enough to supply the line for one day and rolled it onto a smaller reel.  Our arrangement worked well for a week on the first line. After that we duplicated the process on the second line.
Later the company negotiated with the supplier and was able to get tubing in smaller rolls suitable for putting directly on the assembly line.  Within the company there was some resistance to taking a “perfectly good” machine out of service, when it was still being paid for.  When I toured plants in Japan that were practicing lean manufacturing and continuous improvement, I saw several yards filled with equipment covered by tarps.  We were told that this was equipment taken out of service by efforts to make processes lean and reliable.

Thursday, September 8, 2011

Unemployment and the Economy

I have talked to a few "small business" owners over the last month.  I've asked them what most affects their hiring decisions.  Is it taxes?  Is it regulations?  Is it demand?

These are owners of businesses with 100 to 200 employees, focused on manufacturing and importing.  The answer is always demand.  Some noticed a clear drop in demand when gas prices last went up.

They would like lower taxes, and there are regulations that are onerous.  Some regulations seem stupid.  Others make sense and the fact that they apply to everyone in a particular market is seen as a good thing.  A lot of regulations are complex and require hiring consultants to help assure compliance.

But it comes back to the need for demand.  Without demand there is no growth.  Without demand there is a need to reduce labor or reduce hours.   Sometimes both are required.  Construction companies have been particularly hard hit with the real estate collapse.  Hiring requires orders to build.

I come down on the side of government efforts to stimulate demand, through creating jobs that our society needs to have done.  Rehabilitating existing infrastructure and developing new infrastructure are real needs. They offer the opportunity to hire people who in turn will purchase goods and services from others. We should also look at simplifying our tax system and at revising and sometimes simplifying regulations that are onerous.

Tuesday, May 31, 2011

Whose Responsibility Is It?

 I have a reflexive reaction when workers get blamed for problems in the workplace.  I have found that the vast majority of workers in a wide variety of workplaces do the best they can with the material, methods, machinery, and measurements that they are given to do the job.  Often they are severely lacking.  Material is of poor quality and doesn’t meet the specifications (sometimes the specifications don’t even meet the requirements). Machinery frequently jams, malfunctions or breaks down. They are not adequately instructed in the methods required or the reasons to follow them. Insufficient data, or the wrong data, is collected to give them the feedback that they need.

Often workers struggle.  Sometimes they get fed up. Instead of solving a problem or seeking help to solve it, the merely wait for someone else to do it.  They may have even been told that thinking about solving problems or improving the work is not their job.  If this goes on for long, bad habits develop. I have been in plants were it seems that most workers are chatting, drinking coffee, or reading a newspaper, rather than doing productive work.

Edwards Deming said often that the responsibility for solving problems and providing all the resources needed for work lies squarely on management. I agree.  Masaaki Imai points out that fixing blame does little to solve problems and much to interfere with problem solutions. People who risk being blamed are more likely to hide problems.  The manager who asks to understand what went wrong will get a lot more useful information than the one who wants to know who to blame.

If kaizen and lean practices are going to be successful, the bulk of the responsibility falls to management.  This isn’t to say that management knows how to do it. When I have involved General Managers and company Presidents in kaizen workshops (something which can be pretty hard to do, because they are too busy to devote that amount of time  to a workshop), I have often heard them say, “I had no idea.”

So, what do managers have to do?  They need to understand that their organization is a system.  There are flows of material in the system, with a lot of waste between one spot that adds value and another. A big waste is in-process inventory, often not including the material that is actually needed at the moment, because more than necessary of a different material has been produced.

The value adding stations require support around the Five Ms (People [formerly Manpower], Machines, Methods, Measurements, and Material.  Value adding fails, doesn’t get done, gets done wrong, produces poor quality, because one or more of these support systems have been inadequate.  The wrong person has been assigned to the job with inadequate training, or compensation has fallen down and affected morale.  The machines don’t work the way they are supposed to work because their is not an adequate preventive maintenance system.  When machines break down it takes a long time to get them up and running again. Standard methods (the best, easiest, safest ways) have not been developed, communicated, or improved, leaving an untrained worker to use her best judgment.  The worker is expected to “make do” with material that is of poor quality, of insufficient quantity, or not located conveniently.  Wrong things or no things are measured to inform everyone of how we are doing.  The worker does not know what is expected.  The supervisor can’t tell who needs the most help to get back on track.

I have barely scratched the surface here of the kinds of inadequacies that the support systems can present.  Some companies manage all of the support systems quite well.  An awful lot struggle from crisis to crisis, leaving no time to pay attention to the systems issues.

Tuesday, March 29, 2011

Quick Changeover Workshop - Part 2

In the last posting I listed the following techniques to reduce the time it takes to  changeover a machine from one product to another.
1.     A verbal written record of every action of the people doing the changeover
2.     A spaghetti diagram of the changeover operators’ movements.
3.     A measurement of the distant walked, either using a pedometer or counting the operators’ steps.
4.     A written capture of ideas for improving the changeover, as these come to mind.

This is the form that I use make a written record of what people are doing during the changeover that is being observed:

We record the activity of the operator being followed in detail. We especially want to be able to distinguish among the activities that could be done before the machine stops producing or after it is producing again, those that must be done while the machine is stopped, and those which are simply waste or muda.
In the example, the operator could have had the lock and tag ready before shutting the machine down.  This could be “external” time.  The actual act of locking out must be done after the machine is shut down.
Walking to the opposite side of the press adds no value to the changeover process.  If the lever were next to the electrical panel where the lockout is placed, the walking could be eliminated.
The operator must hold the lever down for 56 seconds to release the pneumatic pressure.  We again have waste.  A different release mechanism would allow him to pull the lever or push the button once and go on to the next element of activity.
Now the operator goes to fetch a hand truck. Accumulating product in a container is waste, leading to the additional waste requiring a hand truck to move it.  If the next operation were performed immediately, on an adjacent machine, there would be no need to move these parts with a hand truck.  For immediate purposes, we can think of this activity as potentially external.  The hand truck could be put close at hand before the machine was shut down.
In the workshop we typically leave the three right-hand columns blank until after the changeover is complete, focusing instead on keeping track of the running time at the start of each new activity, in the left-hand column.
Normally, we will fill many pages of this form in one changeover.  After the observation is complete, we categorize each item as Internal, External, or Muda, putting the time for the element in the corresponding column on the worksheet.  We then add up the times in each column and calculate their percentage of total time. The time that must be internal will be a small fraction of the total time, revealing that we spend most of the changeover doing things that are wasteful or could be done before after the period during which the machine is not producing.
The spaghetti diagram of the operators movement gives us a visual representation of the amount of activity that is wasted in movement without adding value.  Here is a typical first spaghetti diagram:

As we make improvements and repeat our observations we can see the impact dramatically by comparing spaghetti diagrams.
Data from a pedometer or by having an observer count the number of steps the operator takes is provides a measure of the potential for improvement and actual improvements obtained in the workshop.  The number of steps and distance traveled should drop dramatically.
Throughout the changeover the members of the team  will have ideas about ways the changeover can be improved.  If all nuts were the same size, we could work with a single wrench instead of the half-dozen sizes we use now. We would waste less time hunting for the right wrench.  If we chance the design of a clamp, we can eliminate a tool altogether.  These ideas should be written down as they come to mind.  Some teams have each observer keep his own notes.  Others have a single recorder to whom all observers give their ideas to be written down. It is useful to note the running time on the note, to place it in context for later discussions.
After the first changeover has been observed, the team gathers to discuss their observations and select improvements that can be done quickly to reduce the time it takes to changeover the equipment, writing the ideas on a flip chart. The Detailed Activity Log is completed by identifying  those activities that could be external and those that are muda.  The team considers what simple changes might eliminate the muda or make internal activity external.  These ease of doing this will vary widely, but there is always much that can be done quickly and inexpensively. 
Tool boards can be installed, on which all of the tools needed are in a designated location and within reach.  The first versions can be done with a magic marker on a piece of cardboard.  In fact they should not be made too permanent and pretty, as we often find ways to eliminate tools, requiring the tool-board to be changed.
Is hunting for fasteners taking up time?  We can pre-stage the exact fasteners that are needed, where they are needed.  Are we spending a lot of time spinning down nuts because bolts are longer than they need to be?  Let’s select bolts of optimum length.  Are we wasting time because small parts fall and must be retrieved?  What can we do with small parts trays to prevent this from happening.
In some types of changeovers we discover opportunities to standardize that will he contribute to reducing the times they take.  Standardizing die heights  can make changing stamping presses quicker.  When there are problems to standardize to a single height, we can we at least minimize the variation by standardizing to two or three heights instead of a half dozen or more.  Often we can we standardize clamps and bolts. Generally we ask, where can we eliminate variation through standardization?
A changeover improvement workshop can be exciting and inspiring.  It is not unusually to reduce the time it takes to conduct a particular changeover in half with one or two iterations, implementing low-cost / no-cost improvements after each observation.  Getting to SMED (Single-Minute-Exchange-of-Dies) will take more work, but the workshop will provide good indications of where that work needs to be done.
There is a danger that the necessary changes will not be standardized and maintained.  While the team was working, everything was meticulously pre-staged, but we did not then put the procedures into place so that the pre-staging is always done.  While the machine is running, who is going to get the tooling and material ready, so that the internal time can be kept to a minimum?  The operator may or many not be able to do it.  If not, who will?  This will require a change in the operating processes in support of changeover.
Quick changeover is not independent of equipment maintenance.  An unreliable machine can be difficult to changeover in a reliable time. 
As with a lot of lean processes, if the quick changeover is to be sustained, it requires a vision of how it fits in the overall system.   This vision must be translated into leadership that helps others see the big picture and understand all of the changes that are required.

Monday, August 30, 2010

A Step-By-Step Process for a Changeover Workshop (Part 1)

Changeovers take time. Different models need different dies, different fixtures, and different settings. Usually, all of these have to be changed. During the changeover process, I’m making nothing. I am very tempted to make more than I need when I have everything set and ready to run.  I may only need 100, but I will go ahead an make 500 or 1,000 units, because at least the machine was productive, and I can put the extra pieces on the shelf, ready for when they are needed.
Then they sit on the shelf.  I didn’t need them when I made them. I t can turn out that now that I have made them, I won’t need them for a long time.  Depending on what “they” are they can get dirty or damaged just from sitting.  The can rust or otherwise deteriorate.  In any case, I’d better keep track of them, because I need to know where I put them when I need them.  So someone will have to keep (or enter into the system) an accurate record of how may I stored and where I put them.
When I need some again, I need to remember to look up how many I have already and where I put them.  Sometimes we go ahead and make a fresh batch because we forget that days, weeks, even months ago, we made some of these.