看板 Lean Architect · Tyshchenko Lean Academy

Kanban — a Pull System

“Make only what is needed — only when it is needed”

The history of Kanban — from Toyota to the whole world
1940
1940s
Taiichi Ohno — the source of inspiration
Taiichi Ohno, a Toyota engineer, studied American supermarkets and saw something revolutionary: shelves are restocked only after a customer takes an item. No forecasts. No “pushing” inventory. A signal from the consumer → replenishment. Ohno realized production could work the same way.
1953
1953
Toyota launches the first Kanban system
The first production Kanban system goes live at a Toyota Motor plant in Japan. Cards (看板 = “signboard”) travel between processes as official “production permits.” No card — not a single part gets made. Inventory drops several-fold. The Just-in-Time era begins.
1963
1963
Spreading across Toyota
The Kanban system is rolled out to every Toyota Group plant and to tier-one suppliers. It becomes part of the Toyota Production System (TPS). Kanban turns into the shared language between Toyota and 300+ suppliers: a request for parts arrives exactly when it’s needed.
1984
1980s
The West discovers Kanban
American and European manufacturers, impressed by Toyota’s quality and efficiency, start studying TPS. Richard Schonberger’s book “Japanese Manufacturing Techniques” (1982) brings Kanban to the West. Ford, GM, and Bosch begin adapting it. The concept of Lean Manufacturing is born.
2004
2004
David Anderson — Kanban for IT
David Anderson at Microsoft applies Kanban principles to software development. Physical cards are replaced by a digital board. Parts are replaced by user stories and tasks. WIP limits keep the team disciplined. In 2010 he publishes the book “Kanban” — and digital Kanban conquers the whole tech world.
2024
Today
Kanban — a universal tool
Jira, Trello, GitHub Projects, Azure DevOps — all are built on Kanban principles. Toyota still uses physical cards on some lines. Kanban is used everywhere from Honda plants to Silicon Valley startups. The principle is the same: make only what was requested — only when it was requested.
4 types of Kanban cards
🏭
Production Kanban
A permit to produce a specific quantity of parts. Triggered when the consuming process takes product from the supermarket
📦
Material Kanban
Requests a material delivery from the supplier. When stock hits the minimum, the card goes to the supplier as an order
🚚
Withdrawal Kanban
Authorizes and governs delivery between processes or areas. Controls how materials move around the plant
🏷️
Location Kanban
Labels storage locations. Defines “what goes where” and “how much” — ties in with 5S (Set in Order)
SAMPLE PRODUCTION KANBAN CARD:
Production
Bearing housing — Line 2
Part number
BRG-2240-L
Qty
50 pcs
Supplying process
Stamping D3
Consuming process
Assembly B1
Lead time
4 h
Card no.
3 / 5
Formula for the number of cards
K = (D × LT × (1 + SS)) ÷ Q
Number of cards in the system
K — number of cards
D — demand per day
LT — replenishment time
SS — safety factor
Q — lot size
Example: D=100 pcs/day, LT=2 days, SS=10%, Q=50 pcs → K = (100×2×1.1)÷50 = 4.4 ≈ 5 cards
Benefits of a Kanban system
🚫
No overproduction
We make only what the next process has taken. Not a single extra part
🎯
Easier prioritization
The cards form a queue — it’s always clear what to work on first
📊
Control over the real flow of materials
Every card is a permit. No card — stop. The system won’t let WIP pile up
👁️
Visual management
Number of cards = allowed inventory. More cards on the floor = an alarm signal
📦 Example 1 — Corrugated shipping cases at a snack packing line (illustrative example)
THE SITUATION BEFORE KANBAN:
A packaged-snacks line at a mid-size food manufacturing plant. Corrugated shipping cases for the case packer were ordered once a week from a forecast. Pallets of cases blocked the aisles — and the case packer still ran short whenever the product mix changed. About once a week, the end of the line stood waiting for cases.
CALCULATING THE CARDS:
D=40 bundles/day · LT=2 days · SS=20% · Q=16 bundles (1 pallet)
K = (40 × 2 × 1.2) ÷ 16 = 6 cards
HOW THE SYSTEM WORKS:
①Every pallet of cases carries a Kanban card with the item number, quantity, and supplier contact
②When the case packer operator opens a new pallet → they drop its card into the “order box” next to the line
③Twice a shift the material handler collects the cards → the order goes to the supplier through the portal
④The supplier delivers within 2 days → new pallets with new cards
BEFORE KANBAN
📉 ~1 case shortage a week
📦 Stock: 20 pallets (8 days)
💰 ~$12,000 tied up
😤 Blocked aisles and rush calls to the supplier
AFTER KANBAN
✓ 1 shortage in 4 months (a supplier delay)
📦 Stock: 4 pallets on average (1.6 days)
💰 ~$9,600 freed up
✓ Clear aisles, ordering runs on its own
🔩 Example 2 — A two-bin system for furniture hardware
THE SITUATION BEFORE KANBAN:
A furniture assembly line uses 150+ kinds of hardware (screws, hinges, handles, drawer slides). The stock keeper can’t keep track of what’s left. The line stops because small parts “suddenly” run out — 6–10 times a month.
THE SOLUTION — A TWO-BIN SYSTEM:
🟠 BIN A (active)
The operator takes parts from here. When it’s empty → puts it back and switches to bin B
🟢 BIN B (reserve)
An empty bin A = a Kanban signal. The stock keeper sees it → orders a refill
Key benefit: The operator doesn’t think about logistics. They see an empty bin → set the signal → keep working. The system manages inventory on its own.
BEFORE KANBAN
📉 6–10 stoppages/month
🕐 ~20 min of downtime each
😤 Constant “firefighting” mode
📊 Manual tracking of 150+ items
AFTER KANBAN
✓ 0 stoppages from shortages
✓ +1.5 h of productive time/day
✓ The stock keeper works to a plan
✓ Automatic signal for all 150 items
🖥️ Kanban in IT projects — a digital Kanban board
THE SITUATION — product development
A team of 5 developers. Without a system, everyone juggles 3–5 tasks at once, nothing gets finished, and the PM can’t see the real status. With a Kanban board and WIP limits, the flow of tasks becomes visible and manageable.
THE TEAM’S KANBAN BOARD (tap a card for details):
📋 Backlog
no limit
Google SSO sign-in
Feature5 pts
OEE report by machine
Report8 pts
Push notifications for audits
Feature3 pts
⚡ In Progress
WIP ≤ 2
Packing line KPI dashboard
Feature13 pts
ERP API integration
Intgr8 pts
✓ WIP = 2 / 2 — limit reached!
👁️ Code Review
WIP ≤ 2
Takt time calculator
Tool5 pts
🧪 Testing
WIP ≤ 2
Time study module
Feature8 pts
✅ Done
Sprint 3
SOP builder v1.0
Feature13 pts
Sign-in and roles
Auth8 pts
WIP LIMITS — THE KEY PRINCIPLE OF IT KANBAN
WIP (Work In Progress) is the number of tasks in one status at the same time. A WIP limit of 2 means no more than 2 tasks “In Progress” at once. Once the limit is reached, a new task can’t start until an old one is finished. This forces you to finish, not to start.
WITHOUT KANBAN
🔄 Everyone juggles 3–5 tasks
❓ The PM doesn’t know the real status
💀 “Almost done” — for weeks
📉 Average task time: 3 weeks
WITH KANBAN + WIP
✓ Focus: 1–2 tasks at a time
✓ Status visible to the whole team
✓ Blockers surface right away
✓ Average task time: 4–5 days
Where it’s used: Jira, Trello, GitHub Projects, Azure DevOps, Linear — all built on Kanban principles. Today more than half of the world’s tech teams use Kanban or Scrumban (Scrum + Kanban).
From Toyota’s shop floor to IT boards — 70 years of Kanban
1
1953
Taiichi Ohno and the supermarket
Taiichi Ohno studied the American Piggly Wiggly supermarket and saw the principle: a shelf is restocked only when an item has been taken. That became the idea behind Kanban at Toyota. The first card in place of a production order — 1953, at the Koromo plant.
2
1970s–80s
Toyota extends Kanban to all its suppliers
Toyota requires all its suppliers to adopt a Kanban system. JIT (Just-In-Time) becomes the standard of Japanese industry. The West first learns about Kanban from Taiichi Ohno’s book “Toyota Production System” (1978).
3
2004
David Anderson — Kanban for IT and software
David Anderson at Microsoft adapts Kanban for IT teams. Cards = tasks. Columns = work stages. WIP limits = a cap on unfinished work. IT Kanban is born — and in 2010 the book “Kanban” comes out and becomes a software development classic.
4
Today
Jira, Trello, Azure DevOps — Kanban everywhere
Millions of teams around the world use Kanban boards: from Toyota and BMW plants to Silicon Valley startups. The principle hasn’t changed in 70 years: do only what is needed now — and only when it is needed.
Fun fact: Ohno came up with Kanban by watching an American supermarket. The irony: an American self-service idea → a Japanese production system → back to the US as Lean Manufacturing.