Lean

Mar 4 2013

Questions from an Industrial Engineer in an Automotive Machine-Shop

I received the following questions from an Industrial Engineer (IE) who has recently moved from vehicle assembly to the machining of car engine parts, blocks, heads, crankshafts, etc., activities that all new to him:

  1. Any reading material you would recommend?
  2. Is takt based off the slowest machine or the machine in the line that makes the least parts?
  3. Knowing cycle times and uptimes of a 30 machine line how do you calculate system uptime?
  4. Should there be more overspeed for machines at the beginning half of the machine line?

Following are my answers:

Any reading material you would recommend?

Industrial Engineering, as taught in universities, is generically about how people work, and gives you no process-specific knowledge. Manufacturing Engineering (ME), on the other hand, is heavily focused on metal working, as if these were the only processes worthy of the name “manufacturing.” To be effective as an IE in a machine shop, you need some familiarity with whatever processes are performed in your shop, such as turning, milling, drilling, reaming, broaching, grinding, or heat treatment. You don’t need to master them, but you need to know them enough to have a meaningful conversation with specialists. And you also need to know about the key operational issues of the machines used to perform these processes, such as lathes, machining centers, drill presses, etc. including how parts are loaded and unloaded, jigs and fixtures, cutting tools, and NC programs.

You will find more than you need to know in books written for MEs, like Degarmo’s Materials and Processes in Manufacturing. I would not attempt to read it cover to cover but instead use it as a reference, to cram on any process you are actually working on. There are other similar books, but this one was co-authored by J.T. Black, who was quite possibly the first American academic to recognize the significance of Lean and make it central to his teachings. My own book Working with Machines is about all types of manufacturing activities that involve the interaction of people and machines which includes automotive machine shops. It includes discussions of takt time, OEE, and availability.

The two main industrial applications of machining are automotive and aerospace, and the two are quite different. In automotive, you remove small amounts of metals from many parts that have been cast or forged near their final shape, in commonly available alloys and in high volume; in aerospace, by contrast, you remove 90%+ of the metal from slabs or forging that look like caskets in exotic alloys and in low volumes. Your needs are in automotive, so don’t waste your time studying approaches that are only used in aerospace. The literature does not always make this distinction obvious, so you have to be on the lookout.

Is takt based off the slowest machine or the machine in the line that makes the least parts?

The takt time is not based on machines but on demand and net available production time. If you have a line that puts out completed parts one unit at a time at fixed intervals, the takt time is the length this interval must have in order to meet the demand within the net available production time, which is the time you can count on the machine actually processing parts. It is not a parameter of your slowest machine but a requirement that even it has to meet.

Knowing cycle times and uptimes of a 30 machine line how do you calculate system uptime?

As you know, uptime ratios are multiplicative, so that, if you have a line of 30 machines, each of which is up 85% of the time, you line is up 85\%^{30}= 0.7\% , which is obviously not workable. But 99% uptime on each machine still only gives you 99\%^{30}= 74\% , which is still too low. So what do you do?

First, you don’t put 30 machines in line. machining cells usually have 5 to 10 machines, including simple, auxiliary machines that rarely break down. And you have buffers between cells that are managed by pull. A cell of 10 machines with 99% uptime will be up 90% of the time. With 5 machines, 98% uptime on each machine is enough to give you 90% on the whole.

Second, you work on improving the machines and customizing them to your needs so that they have fewer breakdowns and can be changed over faster, and you use these improvements to increase the number of machines in line.

Should there be more overspeed for machines at the beginning half of the machine line?

The takt time is set for the entire line. The line meets this requirement if, and only if, the last machine puts out one unit of the product in question like clockwork at the end of every takt interval. For this to happen, you must not only make sure that this last machine is up and running but also that it has a part to work on, and one way to ensure this is to give all the upstream operations a modicum of slack. This strategy, however, works better in manual assembly, where much of the work can be reassigned backwards and forwards among assembly stations in minuscule increments, where you cannot ask a lathe to do milling and vice versa.

The minimum takt time a machining line can support is determined by the capacity of its bottleneck machine, which is usually not last in line.

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Mar 1 2013

Lean in administration at St. Luke’s Internal Medicine | David C. Pate

See on Scoop.it – lean manufacturing

TEAMwork is St. Luke’s application of lean principles. It’s our management operating system. TEAMwork stands for timely, effective, accountable, measureable work. And it’s making its way through St. Luke’s Health System as we gain on our Triple Aim of better health, better care, and lower costs.

Starting last summer, SLIM embarked on a top-to-bottom examination of how it conducted its work. They wanted to eliminate waste by tapping into the potential and knowledge of every member of the clinic team and build a culture of continuous improvement.

 

 

Michel Baudin‘s insight:

The improvements described are all about supplies and the handling of patients by nurses and administrative staff.

There is not a word about any changes to the work of doctors themselves or involvement by doctors in the improvement process. What form might that take? I don’t know, but, the last industrial engineers to work on health care before Lean were Frank and Lillian Gilbreth 100 years ago, and their focus was the work of surgeons inside operating rooms, not patient handling before and after they see a doctor.

The result of their work was the now standard mode of operation in which the surgeon calls for tools that are handed to him by nurses. It seems hard to believe today but, earlier, surgeons would actually leave patients to fetch tools.

Following in the Gilbreths’ footsteps today would mean for Lean Health Care to get involved with the core of the activity: what doctors do with patients.

In manufacturing, successful Lean implementations start with the work of production on the shop floor, not with the logistics upstream and downstream from production. First you worry about line layout, work station design, and the jobs of production operators. Then you move on to keeping them supplied and shipping their output.

See on drpate.stlukesblogs.org

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Feb 28 2013

2nd Tour of Toyota in San Antonio, Texas | Mark Graban

Toyota Tundra powertrain assembly in San Antonio, TX
Toyota Tundra powertrain assembly in San Antonio, TX

See on Scoop.it – lean manufacturing

Blog post at Lean Blog :

“…The plant has performance measures, safety crosses, Kaizen improvements, training schedules, team pictures, and all sorts of information posted everywhere. Our tour guide said, “We love visual management here” — and that includes information sharing.  The boards were all labeled “FMDS”  – or “Floor Management Development System” (see a quick description of it here from a book). That label seems to illustrate Toyota’s focus on developing people… interesting thought that what some people might call “metrics boards” aren’t just for managing and improving company performance, but they’re also for improving people….”

See on www.leanblog.org

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Feb 26 2013

Toyota, Respect for People and Lean | Mark Graban

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Blog post at Lean Blog : A principle that has been often discussed (and hopefully practiced) in the Lean community over the past few years is usually described as “respect for people.” A certain British rabble rouser recently said at a Lean conference “all this respect for people stuff is horse sh*t,” and that it is a “conventional Western management interpretation.” He mocked the idea of “respect for people programs,” although I’m not sure where such a standalone program has ever been attempted.

Michel Baudin‘s insight:
Great post, Mark. In concrete terms, I have found disrespect easier to explain than respect.For example, giving a person a job that requires doing nothing 50% of the time is saying “your time is worthless,” and therefore “you are worthless.”  Many managers do not realize how disrespectful this attitude is, particularly where labor is cheap.
Ignoring complaints about minor safety issues, like sharp edges on a cart, is also showing disrespect.There are many such issues that must be addressed before asking people to participate in improvement and contribute ideas.The Frank Woollard quote in Bob Emiliani’s comment explains why you should pay respect to your people. It’s not about being nice. In the long run, you cannot compete unless your organization fires on all intellectual cylinders.

See on www.leanblog.org

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Feb 22 2013

Why doesn’t Lean work? | A discussion started by Norman Bodek

Norman Bodek asked this provocative question on the TPS Principles and Practice discussion group on LinkedIn, and elaborated as follows:

“Lean is a total system of continuous improvement with everyone involved.

A few years back, I visited Toyota’s plant in Georgetown, Kentucky with the group of executives from various construction corporations. One member of our team asked Gary Convis, then president of Toyota, ” What do you expect from your workers?” Gary answered, “Only two things: come to work and pull the cord.”

Simple, but how many of you attempting to do Lean allow your employees to pull the cord, stop the line, and have everybody, literally everybody in the plant, wait until that one person resolves the problem. I would guess only 1% or less of you that are attempting to implement lean allow your workers to stop the line. Why?

Lean is a very powerful process that has allowed Toyota to grow from a company that made junk in 1952 to one of the largest most successful corporations in the world producing some of the highest quality automobiles available. And the essence of Lean is to empower every employee to become a problem solver, to make every employee self-reliant. But how do you do this? How can you begin to trust your employees that they will make the right decision for the company? I say “simple”, because if Toyota can do it so can you.

Yes, you are running your kaizen blitzes and they are wonderful. Yes, you are doing Six-Sigma and that is wonderful. Yes, you are doing value stream mapping and it is wonderful. Yes, you are doing 5S, setting up cellular manufacturing, doing TPM, Hoshin Kanri, and using many of the wonderful Toyota tools, but you are, for some strange reason, not empowering your employees to be self-reliant.

Toyota probably fearful to build plants in America, suggested to General Motors to set up a joint venture and Toyota would teach them how to use the Toyota production system and be able to transfer it to all General Motors plants. GM, laughingly, selected their worse plant in Fremont, California, NUMMI, and gave it to Toyota to run. One year later, NUMMI became the best plant in the GM system but GM never really learned how to implement properly in their other plants and GM went bankrupt.

I recently came back from Japan, my 81st trip, and was told that Toyota is still the best model to follow. I strongly recommend that you learn how to emulate them and get every single employee involved in continuous improvement. Find a way to let everyone in your company walk on two feet. But, I ask you, ‘How are you going to do it? How are you going to make lean work?'”

There have been 70 comments, as of today, from Sid Joynson, William Botha, Thomas Ligocki, Philip Marris, Anthony Mangione, Peter Winton, Carlos Hernández, and others. My own response was as follows:

Norman’s diagnosis that Lean isn’t working is correct if you are discussing what passes for Lean in the US, and it’s not just an impression. A few years ago, I did my own analysis, the results of which were published as a Viewpoint in Manufacturing Engineering in 2006 . I chose 40 winners of the Shingo Prize and searched Hoovers Online, for comparative performance data with their 400 top competitors. On the average, the data did not show that the Shingo Prize predicted any advantage in profitability, market share or employment growth.

Fundamentally, most Lean programs today are to serious implementations as cheap imitation shoes are to the training of Usain Bolt.

Norman, however, goes one level deeper when he says “Lean is a total system of continuous improvement with everyone involved,” which implies that the key to making Lean successful is to get everyone involved in continuous improvement, and I don’t think that is the case. Don’t get me wrong. It is no doubt a wonderful and useful thing. I just don’t see it as the key.

I find it always enlightening to compare the literature on Lean published in the US with what you find in Japan, which Norman is certainly familiar with, from having organized the translation of several classics in the 1980s. I have in my hands a newer book that I picked up on my last visit to Japan, that has not been translated yet. It is from 2009, by Mikiharu Aoki, a 25-year Toyota alumnus who became a consultant in 2004. The title means “The heart of introducing the Toyota Production System” (トヨタ生産方式導入の奥義), and it is heavily technical.

By contrast, the bulk of the American literature is shockingly light on technical content, which is dismissed as a tactical toolbox you shouldn’t worry about too much. Instead, the literature you should focus strategic issues like change management, motivating people, and calculating metrics.

Crispin Vincenti-Brown identified four dimensions to manufacturing:

  • The engineering of production lines.
  • Logistics and production control.
  • Organization and people.
  • Metrics and accountability.

In the US, the engineering dimension is ignored. Logistics receives some attention, but Lean programs are overwhelmingly focused on the last two: organization and metrics. It is out of balance, and I believe this is the reason these programs fail.

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Feb 19 2013

Oppama Style | Dumontis

See on Scoop.it – lean manufacturing

A look at production behind the scenes at Nissan’s Oppama Plant, where everyday the Nissan Juke, Cube, Sylphy and 100%-electric LEAF roll off the lines

Michel Baudin‘s insight:

I did visit the Oppama plant(追浜工場), in 1980. Then it was making the Nissan Leopard for the Japanese market, the company’s cars were sold in the US under the Datsun brand, and they used Kanbans, which they called “workplates” to avoid borrowing the vocabulary of archrival “Company T from Aichi Prefecture.”

Times have changed. No one then could imagine that Nissan would ever fall under the control of a “second-rate” company like Renault, and even less that this odd couple would actually work while other seemingly better matches — like DaimlerBenz with Chrysler — would fail. And the Oppama plant soldiers on.

In this three-minute video of an 8-hour process, you catch glimpses of stamping, welding, painting, and assembly. The first thing that struck me was to see the superintendent, who was guiding the video tour, wearing a suit and tie. Perhaps it was for the camera but, in other Japanese plants I have been in, it would have been a faux-pas, as executives make a point of not standing out from shop floor operators by what they wear.

The little we see of the operations is as expected, frome the body welding robots  to the “pirate-ship” carts of parts that move along with the line in final assembly and the different types of engines lifted into the car bodies.

The plant has a densely-packed, lived-in look. It has been around for a while, and looks like a place where people make cars. By contrast, some of the newer plants in Germany like Porsche in Leipzig or Volkswagen in Dresden, look like showrooms.

And a hat tip to Dumontis for calling it Oppama Style.

See on www.youtube.com

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