2. Introduction to lean philosophy
Avoid all types of waste in an operation, and reduce cost. Thereby increase the profit.
In all operations there are many types of wastes such as:
Spoilage
Overproduction
Excessive materials handling
Scrap
Rework and repair
Accidents and breakdowns

3. JIT ( JUST-IN-TIME)
JIT is the technique used to achieve the goals set forth by the Lean Philosophy. What is JIT? Produce goods and services exactly when they are needed. In other words not before they are needed, because it costs inventory, not after they are needed, because the customers will be in queue.

4. JIT material flow Traditional approach JIT approach buffer inventory
stage A
stage B
stage C
JIT approach
orders
orders
stage A
stage C
stage B
deliveries
deliveries

5. JIT and capacity utilization
JIT approach
focus on producing only when needed
fewer stoppages
low inventory so problems are exposed and solved
no surplus production goes into inventory
lower capacity utilization, but
JIT and capacity utilization
Traditional approach
focus on high capacity utilization
more stoppages because of problems
high inventory means less chance of problems being exposed and solved
extra production
goes into inventory because of continuing stoppages at stages
more production at each stage

6. The lean philosophy of operations is the basis for JIT techniques that include JIT methods of planning and control
The lean philosophy of operations
Eliminate waste
Involve everyone
Continuous improvement
JIT as a set of techniques for managing operations
Basic working practices
Design for manufacture
Operations focus
Small, simple machines
Flow layout
TPM
Set-up reduction
Total people involvement
Visibility
JIT supply
JIT as a method of planning and control
Pull scheduling
‘Kanban’ control
Levelled scheduling
Mixed modelling
Synchronization

7. Eliminate waste
Avoid any type of waste in production. Waste is any activity which does not add value.
There two devices used in lean operations for improving the wastage:
The Seven Forms of Waste
The 5S’s

8. The seven forms of waste
Over-production
Waiting time (equipment efficiency, labour efficiency)
Transport (moving items around the operation costs and creates no value)
Process – some process creates cost and add no value, so proper design should be made.
Inventory – all types of inventory should be eliminated.
Motion – simplify the work and avoid waste of motion. Avoid unnecessary work that add no value.
Defectives – avoid quality waste.

9. The 5 S’s
Sort (Seiri) Eliminate what is not needed and keep what is needed.
Straighten (Seiton) Position things in such a way that they can be easily reached whenever they are needed.
Shine (Seiso) Keep things clean and tidy; no refuse or dirt in the work area.
Standardize (Seiketsu) Maintain cleanliness and order – perpetual neatness.
Sustain (Shitsuke) Develop a commitment and pride in keeping to standards.

10. Methods for eliminating waste
Throughput time.
Throughput time is the key to find out the waste factor in an operation. Throughput time is the time taken for a product to come from a particular production facility.
2. Value stream mapping
It is a technique that maps a product or service production path from start to finish. It records the direct activities and indirect information systems in the production process.

11. ‘Value stream’ mapping
‘Value stream’ mapping focuses on value-adding activities. It distinguishes between value-adding and non-value-adding activities. It is similar to process mapping but different in four ways:
It uses a broader range of information than most process maps.
It is usually at a higher level (5–10 activities) than most process maps.
It often has a wider scope, frequently spanning the whole supply chain.
It can be used to identify where to focus future improvement activities.

12. There are four steps in the value stream mapping as follows:
Identify (process, supply chain,opertion)
Mapping process
Diagnose problems and suggest changes.
Implement changes.

13. The Involvement of everyone
It is an approach to people management. It encourages team based problem solving. Job enrichment Job rotation, multi-skilling The main objective of this approach is to encourage a high degree of personal responsibility, engagement and ownership.

14. Continuous improvement
This approach is to achieve the ultimate goals of lean philosophy over time or step-by-step. The objective is to achieve good quality with no waste, but any operation will be far from the point, so it is continuous improvement process.

15. JIT Techniques 1.Adopt basic working practices
This is same as involving everyone.
It includes the following:
Discipline – standard for safety, environment, quality of product.
Flexibility – ability to expand responsibilities
Equality – treat all the employees at the same level. For example uniform and so on.
Autonomy – give responsibility
Development of personnel – preparing employees competitive.
Quality of working life- involvement in decision making,job security, facilities in working area
Creativity – improve the job every time.
Total people involvement- staff use ability for the benefit of the company .

16. Design for ease of processing
Design improvements can reduce the production cost.
Emphasize operation’s focus
The main objectives are simplicity, repetition and competence. Learn to focus each process on limited, manageable sets of products, technologies, volumes and markets.

17. Use small, simple machines
Small machines process different products and services simultaneously.
Layout for smooth flow
Flow of materials, data, people must be in smooth manner to avoid delay, increased inventory and waste.
In lean philosophy work stations are closer to avoid inventory.

18. 6.Adopt total productive maintenance
This is to avoid unplanned breakdowns. This is achieved by giving responsibility to process owners or staffs.
6. Reduce step times
Setup time is the time required to change the process from one activity to other. Also known as single minute exchange dies. This is achieved by:
pre-select tools so that a complete unit is fixed to machines.
Attaching different tools to a standard fixture.
Facilitate loading and unloading of new tools.

19. 7.Ensure visibility
The more transparent the operation the more will be chances of improvement. 9. Adopt JIT through the supply chain JIT can be used in whole supply chain. Here stages in a process are the whole business.

20. JIT PLANING AND CONTROL
JIT uses the pull scheduling.
Poor inventory timing creates problems in operations. Inventory timing is controlled by two factors:
Push planning and control – parts or material released as it finished.
Pull planning and control – material release is only by request.

21. Methods of JIT planning and control
2. Kanban control(card or signal)
It is a method of operating pull-based control system, where material is released when required.
Three types of Kanban:
The move or conveyance Kanban – it is a signal to the previous stage for withdrawing the materials from inventory.
The production kanban – signal asking to start producing an item to be placed in inventory.
The vendor kanban – signal for suppliers to feed parts or materials.

22. Two procedures for controlling Kanbans:
Single –card systems
Dual –card systems
1.Single –card systems – used when receiving supply of material from an outside source.
2.Dual-card system – uses both production kanban and move kanban

23. 3.Synchronization
It means the pacing of output at each stage in the process to make sure that the same flow characteristics in the whole process. 4. Mixed Modeling Producing steady stream of each item. For example if 200As, 120Bs, 80Cs, to be produced the mixed model will produce it like AABABCABCA…. 5.Levelled delivery schedule Deliver smaller quantities of all the products in a delivery.

24. JIT in service industry
JIT can be used in service industry. Examples of service JIT – PAGE 485 JIT and MRP JIT is pull system of planning and control, while MRP is push system. But it can be combined in many operations. Characteristics of MRP and JIT – PAGE 486

25. How JIT and MRP can be combined?(coexist)
Both JIT and MRP re different approaches, but it can be combined in several ways. The way in which it can be combined depend on the complexity of product structures, the complexity of product routing, the volume –variety charestristics and the level of control needed.