How To Combat the 7 Deadly Wastes
There’s a great article that was written in 2014 by Industry Week titled, “The Hardest Part of Lean is to See the Waste.” It discusses the famous American industrialist Henry Ford and his remarkable ability to identify wastes in areas his counterparts were blind to. The types of wastes Mr. Ford identified were often hiding in plain sight and easily overlooked as part of the process. The piece quotes Mr. Ford: “Time waste differs from material waste in that there can be no salvage. The easiest of all wastes, and the hardest to correct, is this waste of time, because wasted time does not litter the floor like wasted material.” The article cites a case study in which a fabric-dyeing factory doubled its output by a simple workplace rearrangement. The reorganization reduced the number of steps employees were making by half, and that alone was enough to double production.
This waste is one type of waste we discuss below, called “Motion.” It took a great deal of time to identify this type of waste because there weren’t glaring problems, such as fabric being dyed improperly or shipping errors, staring employees in the face. The job was getting done satisfactorily. But just because the job gets done doesn’t mean it’s getting done the best and leanest way possible. Like Henry Ford said in 1926, “Pedestrianism [competitive walking] is not a well-paying line of work.
Let’s fast forward to the present. Most of us are trying to implement the leanest type of production possible with the least amount of wastes. But most of us end up ignoring a few imperative principles of lean manufacturing.
What Is Lean Manufacturing?
So what do we mean when we say lean manufacturing? Simply stated, the purpose of lean manufacturing is to eliminate all waste from the complete manufacturing system. By complete we mean from the beginning of the manufacturing cycle to the end: how a product is designed, engineered, marketed, sold, entered as an order, processed, delivered, installed, and finally, serviced.
Let’s learn about the seven major contributors of waste in any manufacturing operation. You’ll see that many of the wastes listed below are linked to other forms of waste. It’s possible that fixing one area of waste, in turn, fixes a second area and so on. Take note if your shop has any of these problems! Not only do we help point out the 7 Deadly Wastes, we offer solutions to combat these detrimental wastes.
1. Overproduction
Overproduction occurs when a factory produces more than what’s actually needed to meet demand. What’s so bad about that? This typically leads to accumulated work in other areas. Parts must be stored (and storage costs money), and steps are wasted physically moving over-produced pieces around the factory trying to make room for them. Overproduction can occur when you think you may need more of a part or component to compensate for potential future errors.
So how can we eliminate Overproduction? By simply not making extras. This sounds a bit too simplistic, but if your operation aims at a one-piece flow (moving one piece at a time between work cell stations), you eliminate a lot of headaches. Stop planning for errors. If you’re planning to compensate for human errors, there’s a greater problem in your process.
*TigerStop Tip: Automate your machinery to eliminate human error and to quickly produce the exact number of parts needed, not more. Make what you want when you need it.
2. Waiting
Waiting occurs from a poor balance of work. Idle time is abundant when materials aren’t available when needed. This can arise from defected parts or from work-center downtime. Regardless, it means there’s a problem with the karmic balance of your shop.
Combat Waiting by ceasing all batch-and-queue processing—producing more than one piece of an item and moving it to another operation before it’s needed. Eliminate the waste of materials moved from one process station to the next only to wait in a queue for the next operation. Materials frequently spend 80 percent of their time in the manufacturing process waiting for processing.
*TigerStop Tip: Put automation machinery close to one another at the point of use. Don’t wait for parts to be transported across the factory from one machine to the next.
3. Transportation
Transportation waste occurs when materials are moved in stacks from department to department. Too many long moves open the material to risks, such as being misplaced or damaged. The longer materials are transported, the longer zero value is being added to that material. Value is actually being subtracted from the material in terms of the time and labor to transport it.
You can eliminate Transportation by tackling the previous waste Overproduction. Don’t create excess production that must be moved through your facility and stored. Organization is also a way to combat transportation. Create product work cells and organize your shop in a logical flow so you don’t have to move parts from one end of the building back to the next and on and on. For instance, kanban squares are helpful in creating a logical organizational layout.
*TigerStop Tip: Another great way to fight Transportation waste is to source components locally. Support your local economy and reduce shipping costs for parts. Buying “cheap” components from China won’t save you any money in the long run. Especially when those parts arrive with defects and need to be returned.
4. Inventory
Inventory carrying costs can be 20 to 30 percent of the inventory value per year. That’s huge. Inventory is expensive, takes up precious shop floor room, and is a massive drain on cash flow.
The elimination of Inventory waste can be achieved by making only what’s needed when it’s needed. Aim toward one-piece flow so you don’t have to spend precious time and effort stocking shelves with extra parts. The customer isn’t paying for your extra movement on the shop floor, and it doesn’t add any value to the service or product. Establish Economic Order Quantities (EOQ), or simply, determine the optimal number of units to order that in turn minimizes holding costs. (There’s an EOQ formula to help you calculate this: Q* = √2DK/h.)
*TigerStop Tip: Eliminate set-up time. If you’re worried your machinery set-up time takes too long, you’ll produce more products to compensate. Installing automation with zero set-up times allows you to be in control of when you produce and how much you produce so parts don’t have to be stored in inventory.
5. Motion
We discussed this type of waste at the beginning of this post (the fabric-dyeing factory). There’s a reason walking isn’t a well-paying line of work. When employees have to take too many steps, they’re compensating for an inefficient process, such as a factory layout problem or using outdated equipment. Motion takes time and adds zero value to the end product.
Combat Motion by investing in tools that save time and steps. Reorganize your shop floor to deter additional walking to get tools, materials, and information. Reduce inventory to eliminate extra stacking and lifting of boxes. Make accurate parts the first time to eliminate extra Motion reworking parts.
*TigerStop Tip: Automate the tools in your shop that require the most amount of walking. For example, if you’re walking around your sliding table saw adjusting a manual fence, you’re wasting hours upon hours of time and effort each day. Increase machinery productivity and eliminate unnecessary motion. Learn how to solve this issue with a TigerFence.
6. Work In Process (WIP)
Partially completed work, or WIP, is a large source of waste with zero return on investment. When work enters the production process and is not yet a finished product, it becomes, well, another source of inventory. Valuable time and energy go into making pieces of unfinished goods that must wait and be stored. Furthermore, these are parts the customer hasn’t even paid for yet. It isn’t costing the customer a dime, but it’s costing your operation valuable time and money. And what happens when, upon inspection, those WIP parts are flawed in some way? Now that’s money spent moving and storing parts that end up in the rework station or the scrap bin. Producing too many WIP parts ahead of process hides problems that your organization will have to deal with somewhere in the manufacturing process.
Fight WIP by shifting your operations toward a one-piece flow. Identify the holdups in your operations that cause your team to produce partially completed work and reorganize work cells to produce complete products.
*TigerStop Tip: Automate your machinery to quickly produce single pieces that are accurate. Make to order to eliminate batching and unfinished goods taking up precious shop floor space.
7. Defects
Defects occur when material or labor is wasted and parts or processes must be reworked. They can occur from inaccurate tools (tape measures and manual fences) as well as human error, and cause capacity to be lost.
All defects are expensive, especially if you’re working with costly materials. In your scrap bins, defects are one of the largest sources of waste. So stop looking at scrap bins as garbage; look at scrap bins as a measurement of process failures! Was there some preventative measure you could have taken?
Defects also arise due to Transportation wastes, either internally, a material-handling forklift stab to a piece of aluminum, or externally, damage or defects that occur during shipping.
But the scariest part of Defects is that they may not be detected in the factory. This can be detrimental to your business when found by a customer. Not only do Defects slow down processes and cause bottlenecks in your manufacturing processes, but you can lose customers because of them. Now, all of the marketing money and sales dollars spent acquiring and nurturing leads is fruitless.
We can eliminate Defect waste with process improvements. Such as putting in place quality controls and SPC practices and identifying the source of defects. Do Defects result from human error or inefficient or outdated tools?
*TigerStop Tip: Use equipment designed to eliminate human error and rework. Automating processes and existing machinery makes rework a thing of the past. It also eliminates Motion waste while producing bad parts, which in turn must be corrected and remade. Ultimately the goal is 100 percent accuracy.
Results
Finally, how can we tell if we have been successful in ridding our factories of the 7 Deadly Wastes implementing lean manufacturing principles? Here are six metrics for determining your success:
- Productivity Increase or Cycle Time Reduction
- Floor Space Reduction in Square Feet
- Travel Distance Reduction in Feet
- Quality: Internal Scrap Reduction, Rework Hours Reduction, % Yield Increase
- Inventory: Cost/Turns
- Resources, Proper Use of People, Overtime Hours Reduction
Resources:
Levinson, William A. Industry Week, Dec. 29, 2014. “The Hardest Part of Lean is to See the Waste.” Levinson Productivity Systems.
Making the Numbers Count: The Accountant As Change Agent on the World Class Team, by Brian H. Maskell
Real Numbers: Management Accounting in a Lean Organization, by Jean E. Cunningham, Orest J. Fiume
LEAN World Class Manufacturing: The Lessons of Simplicity Applied by Richard J Schonberger
The Complete Productivity Press Shopfloor Series by The Productivity Press Development Team