Post on 12-Sep-2014
description
KANBAN SYSTEMS
SHUBHAM GUPTA
11bme1100
https://www.youtube.com/watch?v=ku5D9TqTvrc
• It’s a scheduling system for just in time production.
• First used in Toyota in 1953 in their machine shop.
• Kanban refers to the posting board (and the inventory control cards posted there) where the evolution of the manufacturing process would be recorded.
• The Kanban system is a manual information system that relies on various types of inventory control cards.
• It’s development is closely tied to the development of SMED: Single Minute Exchange of Dies, that allowed model changeovers to take place in minutes rather than hours.
• The Fundamental Idea of JIT – and Lean Manufacturing Systems in General (an Americanization of the Toyota P. S.) – is to empower the workers to make decisions and eliminate waste wherever it is found
What is Kanban system?
How it works?• Idea is similar to one used in supermarket
• A small stock of every item sits in a dedicated location with a fixed space allocation
• Customers come to the store and visually select items
• An electronic signal goes to the supermarket's regional warehouse detailing which items have sold
• The warehouse prepares a replenishment of the exact items sold.
• Kanban uses the rate of demand to control the rate of production, passing demand from the end customer up through the chain of customer-store processes
• Also called a pull system as demand creates a supply.
Double sided racks.
Stacking bins, when top is empty, remove and start using the bottom bin.
Variable size stackable bins
Double sided racks
Special twinbins, top holds secondinventory, when bottom is empty, pullmiddle lever that allows top inventory
to drop into lower bin, flag pops upidentifying upper bin needs to be
refilled.
Stacked supplyReserve supply behind
Principle
• It works on the principle of demand and not forecast
• According to this system, A company should not make large amounts of stock and then try to sell it. Companies need to be aware of the market place and what the customers wants.
• The pull system uses visuals to signal when parts need to be replaced.
How is signaling done?
• Earlier cards (kanban in japanese) were used to signal the demand for any product
• Nowadays electronic kanbans are used that use sensors and computers.
• Eg: Bar code scanners upload sold items in computer that gives signal to the warehouse
Positive Results
• Employees do not need to be assigned a job, they are allowed to perform work when and where it is needed.
• The skill level of employees is increased and the variety gives them more satisfaction from their work.
• Improves the accuracy of manufacturing schedules
Advantages Disadvantages
JIT PULL
Limited and known Final Inventory Every job is a ‘High Stress’ Rush
orderUnnecessary paperwork is eliminated
Workers effectively consume their time & Raw Materials
on what is actually needed
Balanced systems MUST be in place
Quality MUST be High – each piece has a definite place
to go – else immediate feedback is given
{error is less}
Setup times will greatly impact
throughput
Any problem will lead to unhappy
customers (either internal or
external)Enhances supplier/customer relationships
Focus on The Kanban
• Typically it is a 2-card system
• The P (production) Card and W (withdrawal) Card
• Limits on product inventory (number of P & W cards) are set by management policy
• The count is gradually lowered until problems surface
• The actual target level (card count) is based on short term forecasting of demands
Focus on The Kanban
• So how many cards? –speaking of which, a card is associated with a container (lot) of product so the number of P & W cards at a station determines the inventory level of a product!
is # of Kanbans
D is 'average' demand
L is lead time (proc+wait+travel+others)
w is buffer stock/ set by policy
typically 10% of DL
a is container cap. < 10% of daily demand
DL wy
a
y
In the last few years, systems sending kanban signals
electronically have become more widespread. While
this trend is leading to a reduction in the use of kanban cards in aggregate
In Oracle ERP (enterprise resource planning), kanban is used for signaling demand to vendors through e-mail notifications
A Red card lying in an empty parts cart conveys that more parts are needed.
Three-bin system
One bin is on the factory floor (the initial demand point), one bin is in the factory store (the inventory control point), and one bin is at the supplier's business. The bins usually have a removable card containing the product details and other relevant information — the classic kanban card.
Just PlaY !!!!