Pull Systems and Kanban

Pull is a key principle of lean thinking.  We often think of pull and kanban synonymous terms; however, they are not.  Kanban, which means "sign" or "signboard" in Japanese is the signal that makes a type A pull system work.  In this video, kanban and pull systems are explained.

A Type B Pull System - Sequential Pull Systems and FIFO Lanes

When people talk about pull systems, they are often referring to a replenishment pull system, sometimes called a type "A" pull system.   What is often missed is that there is an alternative to a type "A" pull system.  We call this a sequenced or sequential pull system.  This type "B" system works well when maintaining a sequence of work but controlling the time and quantity between operations is important.  Unlike a replenishment pull system, a type "B" pull system does not require storing inventory by part number between operations.  Instead, jobs, parts, or information is stored in FIFO (First In First Out) lanes that limit the quantity and maintain the sequence of work between operations.  Both type "A" and type "B" pull systems are excellent, and each has its place within a manufacturing, healthcare, or other service organization.  And, in case you were wondering, there is a type "C" pull system, but this is really a mix of "A" and "B" in which some products are utilizing replenishment pull and some are utilizing sequential pull through the same value stream.  Following is our new video on the topic of sequential pull.