This document provides an introduction to Just-in-Time (JIT) and Lean operations principles. It discusses that JIT aims to produce the right part at the right time with no waste. Key aspects of JIT include eliminating waste, reducing variability, and improving throughput. Specific tactics covered include implementing the 5S methodology, using kanban systems for pull production, establishing JIT partnerships with suppliers, and focusing on small lot sizes, reduced set-up times and lead times to minimize inventory levels. The document also contrasts JIT with Lean operations and discusses approaches for implementing JIT and Lean principles in both manufacturing and service industries.

1. JIT and Lean Operations

2. Introduction to JIT
• Just-in-time (JIT) is an approach which aims to produce the
right part in the right place at the right time.
• It is a philosophy of manufacturing based on planned
elimination of all waste and on continuous improvement of
productivity
• It is a Japanese philosophy, firstly introduced by Toyota

3. • Good production systems require that managers address
three issues that are pervasive and fundamental to
operations management
• eliminate waste,
• remove variability,
• and improve throughput

4. 1. Eliminate Waste
 Waste is anything that does not add value
from the customer point of view
 Storage, inspection, delay, waiting in queues,
and defective products do not add value and
are 100% waste

5. Taiichi Ohno’s Seven Wastes
 Overproduction
 Waiting
 Transportation
 Inventory
 Motion
 Over processing
 Defective products
Abbreviation: TIMWOOD

6. The 5 Ss
• 5s is checklist for better housekeeping
• Developed in Japan
• Helps lean operations
1. Structure/Organization(Seiri)
• separating items that are essential to the job from those that are not
• Placing the vital items in convenient locations
2. Systemize/Neatness (Seiso)
• Work area should be neat
• It reduces the time taken to locate the items

7. 3. Sanitize/cleaning(Seiton)
• If the environment is clean, individuals will all start to maintain cleanliness
• Regular thorough cleaning is necessary and specific cleaning
responsibilities should be assigned
• Dirty environment generates negative thoughts and pessimism
4. Standardize(Seiketsu)
• emove variations from processes
• Following standard guidelines, employees better understand the working
environment and work within it quickly and safely
5. Self Discipline/Discipline(Shitsuke)
• Following the defined rules and regulations into the day-to-day working
culture of organization

8. 2. Remove Variability
 JIT systems require managers to
reduce variability caused by both
internal and external factors
 Variability is any deviation from the
optimum process
 Inventory hides variability
 Less variability results in less waste

9. Sources of Variability
1. Incomplete or inaccurate drawings or
specifications
2. Poor production processes resulting
in incorrect quantities, late, or non-
conforming units
3. Unknown customer demands

10. 3. Improve Throughput
 The time it takes to move an order from
receipt to delivery
 The time between the arrival of raw materials
and the shipping of the finished order is called
manufacturing cycle time
 A pull system increases throughput

11. Key Elements of JIT
• Stabilize and level the MPS with uniform plant loading
• Create a uniform load in all work centers through constant daily
production or mixed model assembly (producing same mix of
products each day)
• Reduce or eliminate setup times
• Operations should aim for single digit setup times
• Can be accomplished through better planning, process redesign
and product redesign
• Reduce lot sizes (manufacturing and purchases)
• Manufacture or purchase in small lots
• Requires close tie with the suppliers

12. • Reduce lead times (production and delivery)
• Reduce production lead times by placing work centers closer, using
cellular layout and reducing queue length
• Reduce delivery lead time by making better tie with the suppliers
• Preventive maintenance
• Use a machine and worker idle time to maintain equipment and
prevent breakdowns
• Flexible work force
• Workers should be made versatile
• Require supplier quality assurance and implement a zero
defects quality program
• Quality at source program must be implemented to give worker
personal responsibility for the quality of the work they do and
authority to stop when something goes wrong

13. • Small-lot (single unit) conveyance
• Use control system such as Kanban to convey parts
between work stations in small quantities (ideally one unit
at a time)
Kanban: a visual display board that provides information about the
stock of materials and supplies

14. Just in Time and Competitive Advantage
• JIT is of utmost importance in the cut throat
competition scenario of every industry
• JIT provides competitive advantage by
• Reducing inventories
• Fastening the process of quality monitoring
• Increasing the responsive capability to the demand
• Increase quality and efficiency

15. Contd.

16. Contd.

17. JIT Partnerships
 JIT partnerships exist when a supplier and
purchaser work together to remove waste and
drive down costs
 Four goals of JIT partnerships are:
 Removal of unnecessary activities (like inspection,
receiving, paper works, bidding, etc)
 Removal of in-plant inventory
 Removal of in-transit inventory( by suppliers
locating nearby firm, and consignment inventory)
 Obtain improved quality and reliability

18. Contd.

19. • Layout determines how the raw materials are travelled
before finished goods and services would be created
• JIT lay out reduce wastes in operations
Tactics for JIT layout
• Distance reduction
• High flexibility
• Impact on employees
• Reduce the space and inventory
JIT Layout

20. Distance Reduction
 JIT layout focus on reducing the total length of layout
as much as possible
 Often U-shaped layout for shorter paths and improved
communication
 Often using group technology concepts
group technology: a manufacturing technique in which
functionally-grouped machine(producing parts or products
with similar characteristics) are organized into cells to
achieve high repeatability levels.

21. High Flexibility
 Cells are made highly flexible and
interchangeable
 Applicable in office environments as well as
production settings
 Cells designed to be rearranged as volume or
designs of product change
 Facilitates both product and process
improvement

22. Impact of Employees
 Employees may be cross trained for flexibility and
efficiency
 Highly qualified, skilled, experienced and employees
only handle the operation layout or cell without
creating the waste
 Improved communications facilitate the passing on of
important information about the process
 Workers become their own inspectors, personally
responsible for the quality of their outputs

23. Reduced Space and Inventory
 With reduced space, inventory must be in
very small lots
 Units are always moving because there is no
storage

24. JIT Inventory
Inventory is at the minimum level
necessary to keep operations running
JIT Inventory Tactics
• Reduce or Eliminate Setup Times
• Reduce Lot Sizes (manufacturing and purchase)
• Reduce Lead Times (production and delivery)
• Reduce the Variability
• Reduce Setup Costs

25. 1. Reduce Setup Times
• Aim for single digit setup times through better planning, process redesign,
and product redesign
2. Reduce Lot Sizes (manufacturing and purchases)
• Just in time has also come to mean elimination of waste by reducing
investment in inventory
• Ideal situation is to have lot sizes of one pulled from one process to the
next
3. Reduce Lead Times (production and delivery)
• Production lead times can be minimized by
• moving work stations closer together,
• applying group technology
• cellular manufacturing concepts
• Reducing queue length
• Improving the coordination between successive processes

26. • Delivery lead time can be reduced by
• closer cooperation with suppliers,
• Inducing supplier to locate near the factory
4. Reduce the variability
• Jit eliminates the variability in the production system

27. Reduce Variability
Inventory level
Process
downtimeScrap
Setup
time
Late deliveries
Quality
problems

28. Inventory
level
Reduce Variability
Process
downtimeScrap
Setup
time
Late deliveries
Quality
problems

29. Inventory
level
Reduce Variability
Process
downtime
removed
No scrap
Setup
time
reduced
Late
deliveries
Quality
problems
removed

30. 5. Reduce Inventory
• Reducing inventory uncovers the “rocks”
• Problems are exposed
• Ultimately there will
be virtually no
inventory and no
problems
• Shingo says “Inventory is evil”

31. 6. Reduce Setup Costs
 High setup costs encourage large lot sizes
 Reducing setup costs reduces lot size and
reduces average inventory
 Setup time can be reduced through
preparation prior to shutdown and
changeover

32. Better scheduling improves performance
JIT Scheduling
JIT Scheduling Tactics
Communicate schedules to suppliers
Make level schedules
Perform to schedule
Seek one-piece-make and one-piece move
Eliminate waste
Produce in small lots
Use Kanbans
Make each operation produce a perfect part

33. Level Schedules
• Also called “Jelly bean” scheduling
• Process frequent small batches rather than
a few large batches
• Make and move small lots so the level
schedule is economical

34. Scheduling Small Lots
A B CA AAB B B B B C
JIT Level Material-Use Approach
A CA AA B B B B B C CB B B BA A
Large-Lot Approach
Time

35. Kanban Production Control System
• Kanban is the Japanese word for card
• Many different sorts of signals are used, but
the system is still called a kanban
• I is a pull production control system
• It uses simple visual signals to control the movement of
materials between work centers as well as production of
new materials to replenish those sent downstream to
the next work center

36. Dual Card Kanban
• As used by Toyota there are two types of Kanban
• Production Kanban: signals the need to produce more
parts
• Withdrawal(move or conveyance) Kanban: signals the
need to withdraw parts from one work center and deliver
them to the next work center

37. Dual Card Kanban Rules
1. No parts are made unless there is production Kanban
to authorize production. In absence of production
Kanban, the process remains idle, workers perform
other activities
2. There is exactly one Kanban per container
3. Containers for each specific part are standardized and
they are always filled with the same quantity

38. Determining the number of Kanban cards or
container
• The number of JIT system sets the amount of
authorized inventory
• Number of Kanbans (containers) =
𝐷𝑒𝑚𝑎𝑛𝑑 𝑑𝑢𝑟𝑖𝑛𝑔 𝑙𝑒𝑎𝑑 𝑡𝑖𝑚𝑒 + 𝑆𝑎𝑓𝑒𝑡𝑦 𝑆𝑡𝑜𝑐𝑘
𝑆𝑖𝑧𝑒 𝑜𝑓 𝐶𝑜𝑛𝑡𝑎𝑖𝑛𝑒𝑟

39. Advantages of Kanban
• Kanban helps in meeting schedules reducing the time and
costs required by setups and economical material handling
• Small batches allow only a very limited amount of faulty or
delayed material
• It keeps the operations away from all the pitfalls of keeping
inventory

40. JIT Quality
 There is Strong relationship between JIT and
Quality
JIT cuts the cost of obtaining good quality
because JIT exposes poor quality
Because lead times are shorter, quality
problems are exposed sooner
Better quality means fewer buffers and allows
simpler JIT systems to be used

41. JIT Quality Tactics
Use statistical process control
Empower employees
Build fail-safe methods (poka-yoke,
checklists, etc.)
Expose poor quality with small lot JIT
Provide immediate feedback

42. Difference Between Lean and JIT
• JIT is a tool of Lean where as Lean is a total business strategy
• Lean is externally focused on customer where as JIT is
internally focused
• JIT’s role is to explicitly highlight process problems while lean
aims at eliminating the problems

43. Lean Operations
Different from JIT in that it is externally focused on the
customer
Starts with understanding what the customer wants
Optimize the entire process from the customer’s perspective
Lean operation means identify what customer prefer and make
the necessary arrangement to the creation of value for them

44. Building a Lean Organization
 Transitioning to a lean system can be
difficult
 Lean systems tend to have the
following attributes
 Use JIT techniques
 Build systems that help employees
produce perfect parts
 Reduce space requirements

45. Building a Lean Organization
Develop partnerships with
suppliers
Educate suppliers
Eliminate all but value-added
activities
Develop employees
Make jobs challenging
Build worker flexibility

46. Lean and JIT Operations in Services
• When JIT is used in the context of services, the focus is often
on time needed to perform service
• Focus on inventory reduction
• Emphasis on
• Consistent high quality
• Standard work methods
• Flexible workers
• Close supplier relationship

47. Tactics for Deriving JIT Benefits in Services
• Eliminate disruption
• Workers should not be disturbed while working
• Make the System Flexible
• Though standardization works better but the employees should be
able to perform the varieties of works if needed
• Reduce setup times and processing times
• Eliminate waste
• Minimize work in process

48. • Simplify the process
• When customers are part of the system
• Use of machines like ATMs, vending machines, mobile phone
recharge machine, etc

49. Methods of Minimizing Non-sampling Errors
• Checking the sampling process
• Preparation of questionnaire
• Pilot survey
• Fix procedures
• Use of competent manpower
• Provide information
• Provide training
• Use of experts
• Checking data processing and analysis