By Shannon Wetzel, Managing Editor, and Shea Gibbs, Senior Editor

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You’ve seen presentations on it. You’ve heard your peers talk about it and your customers push it. Your competitors have splashed it on their brochure and website, and you’ve probably Googled it. Lean manufacturing. It’s the religion of the industrial sector—everyone has an opinion and a definition.

Put simply, lean manufacturing is a method of improving your processes so that you are creating more value with less work. “If you’re not doing something to add value, you are creating waste,” said Theodore Schorn, general manager of corporate quality, Enkei Corp., Columbus, Ind. “If you want to save money, you can benefit from lean manufacturing.”

While “lean manufacturing” is really a generic term for improving the efficiency of a plant, engineers have developed distinct systems and tools that describe specific techniques for achieving better efficiency, each with their own labels, terminologies and measuring systems. Many in the industry agree that modern lean manufacturing philosophy is based on the Toyota Production System, which some argue was inspired by Henry Ford and his assembly line.

Various lean experts will point to value-stream mapping, 5-S initiatives, kaizen events, and other tools to achieve a lean company. But whatever the method, most will tell you the basic tenets are the same: eliminate waste and streamline product flow.

“You can do lean manufacturing without the jargon,” said Frank Peters, associate professor of manufacturing/industrial engineering at Iowa State Univ., Ames, Iowa. “It just takes the effort of defining your facility’s flow path and identifying where the delays are.”

Use the following answers to frequently asked questions about lean, and take the mystery out of manufacturing’s hottest buzzword.

1. Why Would My Plant Want to Go Lean?

The benefits of lean manufacturing in high volume shops are relatively obvious because the tasks are repetitive. It can be more difficult to see why lean would be useful in metalcasting facilities that produce a variety of parts in low to medium volumes on any given day.

“In some businesses that have batch operations, it is hard to make an assembly line. It’s not easy to connect all separate processes feeding into the main one,” said Jay McCreary, partner at Flow Vision, Dillon, Colo., a lean consulting firm. “A lot of people in the metalcasting industry view metalcasting as a black art. But it’s not a black art, it’s just a manufacturing process with predictable causes and effects.”

McCreary likened starting a lean program to metalcasters giving themselves their own stimulus check. One of the goals of lean is to eliminate inventory, which ties up cash flow. Inventory on your shop floor is an investment your company has made that won’t be returned until the customer pays for its delivery. More inventory sitting in the shop means more money tied up in the process and less money available for regular operation costs or capital investments.

“If you had $20 million in inventory and eliminated $10 million of it, that’s cash flow for the metalcasters’s pocket,” McCreary said. “Everybody’s looking for a bailout right now. Well if you want cash, realize that you have it invested in your own factory. There’s your bailout.”

Applying lean initiatives to your facility also can help improve quality, safety, lead times and efficiency. Trimming the excess out of the metalcasting process reveals hiccups in your organization that routinely lead to errors and downtime. In a lean operation, members of your organization can investigate the root causes.

For example, say castings are piling up behind a trim press in a permanent mold facility. In a lean operation, this will be clear, whereas in a non-lean operation, the buildup of castings is assumed to be part of the proper work flow. Once the visual determination of a bottleneck has been made in a lean operation, management can begin asking why it has occurred.