The focus on value is central to the success of TPS. TPS designates waste as muda in Japanese. One of the principal ways to reduce waste is to ask whether the customer is willing to pay for the feature in question. If the answer is "no," then TPS designates it as waste. TPS identifies seven wasteful activities that consume time and can be eliminated once identified:
- unwanted transporting
- inappropriate processing
- unnecessary inventory
- excessive movement
- defects in the product or process that require reworking or repair
Although TPS might look distinctive and original at first glance, it closely resembles the concept of lean manufacturing, which originated with the American automobile industry during the time of Henry Ford.
A direct connection exists between "lean manufacturing" and waste (muda). Lean manufacturing aims to reduce variables related to inventory, delivery, cycle, and setup time. Furthermore, it endeavors to elevate quality, boost customer satisfaction, and encourage employee participation and esteem within the organization.
Lean manufacturing also achieves benefits such as eliminating waste by creating a culture of constant improvement that centers on the needs of the customer. It features a set of key principles, as shown below:
Cellular manufacturing involves the stationing of manufacturing units, equipment, and crew members as "cells," allowing for an unbroken and even movement of inventory and material from start to finish. This usually entails a single process/product flow line.
Pull scheduling involves setting up effective and inexpensive methods of managing production and inventory. Many manufacturers also use the Japanese system of Kanban to implement pull scheduling.
Six Sigma and total quality management involve the application of an effective quality-control system to eradicate product and system defects from the production process.
Rapid setup is also known as single-minute exchange of die (SMED) and calls for quick and predictable setup. It helps reduce setup costs and allows production of smaller lots. It also rationalizes the flow of material during the manufacturing process.
Lean manufacturing complements TPS in many ways, as both focus on the customer and attempt to understand future market trends. Both systems require a top-down management approach and the capacity to allow employees to make local decisions. Both systems require the willingness, persistence, and faith that are in many ways counterintuitive to conventional learning systems. If they implement lean manufacturing properly, companies stand to gain by blending the core principles of these highly regarded philosophies.