Mass Production & Lean: What’s the difference?

Assembly line of mass production

Mass production is not considered to be a Lean production method. At the height of its innovation however, it did effectively lower the unit cost of many goods and improved the efficiency of facilities. In the spirit of Lean and continuous improvement, it’s important to keep finding ways to improve the organization and over time, it was clear a better solution may exist.

What is mass production?

Since Henry Ford’s assembly line, mass production has long been a popular production method for manufacturers. With the introduction of the moving assembly line, products were no longer made by just one worker, but rather products moved around the facility while employees would work on different steps of the process. When set up, a facility rapidly produces a very high quantity of the same product; copies of the same exact product are manufactured and travels around the facility in a large batch.

When sending large batches through the production line, production is based off a forecast of customer demand. This is not an exact science, and changes in demand may not always be accurately predicted. Because of this, mass production typically results in overworked machines, excessive inventory, and a number of products that must be reworked.

What is Lean manufacturing?

The methodology of Lean was born out of necessity. While rebuilding the economy after World War II, many Japanese manufacturers learned about production strategies emerging from America like Training Within Industry and Statistical Process Control. One company that took particular notice to these teachings was the Toyota Motor Company.

At the time, Toyota Motor Company was already practicing Jidoka (autonomation) and leaders adap

ted some of the new practices including Kaizen, Gemba, Quality Circles, and more to build the foundational tools of the Toyota Production System. As the automobile manufacturer’s wastes quickly depleted and their production line ran smoothly, other companies began to notice. Soon, organizations all over the world started to implement the same strategies, and philosophy of TPS evolved to Lean manufacturing.

Lean manufacturing addresses the major wastes that results from mass production, defined by Toyota as the 7 Wastes of Manufacturing: Transportation, Inventory, Motion, Waiting, Overproduction, Over-processing, Defects.

When a company is producing at a rate higher than customer demand, they are losing money, time, and other valuable resources. Lean manufacturing operates a JIT production method using Kanban cards. Instead of sending large batches down an assembly line, production only begins when there is actual customer demand. So, instead of making enough “just in case”, businesses are manufacturing exactly how much is needed to meet demand on time.

A visual cue, typically a Kanban card of bin, is sent down the line to trigger the next production step. For instance, a customer orders hat online and submits the order online. The person in charge of tracking orders would then send a Kanban card to the production line, alerting them a new product must be started. This card will then travel with the item until it leaves the facility for delivery. This kind of system ensures facilities are only using the resources needed to meet the demand of customers.

Lean manufacturing encompasses a wide range of tools and strategies. There is organization in the workplace, the empowerment of employees, the philosophy of continuous improvement, and the Lean production method of just-in-time manufacturing. When implemented together, an organization can begin cutting out the wastes and improving their efficiency.

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