The foundation of lean manufacturing includes the following tools:

• 5 S’s - Various housekeeping activities are often used first in adopting the continuous improvement way of life and are:
— Sort out what is unneeded
— Straighten what must be kept
— Scrub everything that remains
— Stabilize - spread the clean routine and provide employees with training and time to improve their work areas
— Standardize - establish a cleaning schedule; this requires self-discipline

• 5 Why’s - When a problem is found ask "why" five times. Repeating why five times helps find the root cause of the problem rather than merely responding to symptoms.

• Visual factory - Information is made available and understandable at a glance for each operator to see and use in achieving continuous improvements.

• Focus groups - Process improvement teams are trained and responsible for detecting waste. Departmental barriers are eliminated and replaced with cross-functional teams that study a process and then immediately implement improvements.

The remaining lean manufacturing tools include:

• Quality tools - Typical quality tools are flow charts, frequency histograms, Pareto diagrams, cause and effect diagrams, and control charts.

• Poka yoke - Poka Yoke are simple, low-cost devices that prevent defective parts from being made or passed on in the process. Poka Yoke eliminates defects by eliminating mistakes.

• Seven wastes - Ohno defines waste as all elements of production that only increase cost without adding value the customer is willing to pay for. The seven wastes of manufacturing are:
— Waste of producing more product than needed
— Waste of inventory - any supply in excess of required to produce product
— Waste of waiting - idle operator or machine time
— Waste of motion - movement of people or machines which does not add value
— Waste of transportation - any material movement that does not directly support value-added operations
— Waste of making defective parts
— Waste of processing - any process that does add value to product

• TPM - Total Productive Maintenance consists of a company-wide equipment maintenance program that covers the entire equipment life cycle and requires participation by every employee.

• SMED - Single Minute Exchange of Dies is a system that allows the mixing of production without slowing output or creating higher costs from waste of setup.

• Work balancing - Work balancing maximizes operator efficiency by matching work content to Takt time. Takt time is the rate at which the customer requires the product and is computed as:
Takt time = Available work time per day divided by Daily required customer demand in parts per day

• Cells - Proper placement of machines is essential. Benefits of good cell layout are reduced inventory, balanced work, less walking time and an improved work area.

• One-piece flow - To minimize work-in-process, operators should focus on one part through the process before starting the next part.

• Kanban - A kanban system is an information system that controls (pulls) the required parts in the required quantities at the required time.

Source: University of Alabama-Huntsville

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