Continuous Improvement and Lean
Kaizen, 5S and SMED, and the Lean tools built on them: Gemba, the 8 wastes, JIT, push vs pull, Kanban, Jidoka, poka-yoke and Heijunka.
Real case
At a pharmaceutical plant in Barranquilla (Colombia), changing over a soft-capsule encapsulating machine to a new product took 240 minutes, with about 20 changeovers a month. With SMED, 9 activities (91 minutes) started to be done while the machine was running, and the time with the machine stopped fell to 150 minutes: 37.5% less, about 30 hours of capacity freed per month without buying equipment.
Source: Thesis, Universidad Nacional Abierta y a Distancia (UNAD), Colombia. See the article
11 articles
Gemba and Genchi Genbutsu: going to see where things happen
Gemba is the place where value is created and problems show up. Genchi Genbutsu is the Toyota principle of going to see it with your own eyes before deciding. A walk through the Gemba, with questions and respect, is a Kaizen tool.
Heijunka: production leveling
Customer orders go up and down, but a factory performs better at an even pace. Heijunka takes the order volume for a period and spreads it out as the same quantity and the same product mix every day.
Jidoka and Andon: stop the line when something goes wrong
Jidoka is the second pillar of the Toyota system: giving machines and people the ability to detect a defect and stop, so they do not keep producing errors. Andon is the light board that signals what is happening and where.
Just in Time (JIT): produce only what is needed, when it is needed
Just in Time is one of the two pillars of the Toyota system: each process produces only what the next one needs, at the moment it needs it. It demands defect-free quality, quick changeovers and a leveled flow.
Kanban: cards, containers and how many are needed
Kanban is the visual signal that tells a workstation what to produce and how much. The number of cards in circulation sets how much inventory is allowed between workstations, and it is calculated from demand, replenishment time and a safety margin.
Poka-yoke: designing so the error cannot be made
Poka-yoke are devices and designs that prevent an error or catch it instantly. It is the cheapest form of quality: instead of asking people not to make mistakes, you design the workstation so that making a mistake is hard.
Push vs. pull system: producing by forecast or by consumption
In a push system each workstation produces and pushes to the next one according to a plan; in a pull system each workstation produces only when the next one asks for it. The difference decides how much material piles up between workstations and how quickly problems show up.
The mudas: the 7 (or 8) wastes of Lean
Muda is the Japanese word for waste: any expense that does not help produce value. Learning to see it is the first step of Lean, and the list has seven classic wastes plus an eighth that several authors add.
What 5S is and how to implement it step by step
5S organizes the workstation in 5 stages: sort, set in order, clean, maintain and discipline. With red tags, audits and an example applied to a maintenance tool crib.
What is Kaizen: origin and philosophy of continuous improvement
Where the word Kaizen comes from, how it differs from a big overhaul, and how a Kaizen event is applied in maintenance.
What is SMED: how to reduce changeover time
SMED separates what can be done while the machine is running from what requires stopping it. With the method's 5 steps and a real case of a pharmaceutical encapsulation machine that cut its setup from 240 to 150 minutes.