neha.bhonsale
New member
JUST IN TIME PRODUCTION
1. In the new competitive environment as the customer becomes choosy, keeps changing his tastes and demands variety to choose from mass production is inadequate for most of the products. In the days of Henry Ford the cost was the only criteria and customers were happy with an affordable price and there weren’t many suppliers. It was a seller’s market
2. The ratio quantity/variety determines the production system. For large ratio mass production is indicated. As the variety is increased and the ratio comes down we move towards batch production. As the variety further rises the batch becomes smaller and smaller to produce
3. But as the batch size becomes smaller than the EBQ the set up costs rise and production becomes uneconomical
4. If we reduce the setup cost/setup substantially we shall find that the batch quantity can be reduced without increasing the total inventory costs. The EBQ will come down and start approaching one, as the set up cost is further slashed down. As this happens we move towards a new production system called Just In time production system
WHAT IS JUST IN TIME?
1. JUST IN TIME IS A PRODUCTION SYSTEM – a combination of flow system and batch system
2. JIT is producing when the demand is placed on the system in minimum lead time
3. It is producing a variety of products just in time when they are demanded.
PRINCIPLES IN JIT
1. Inventory reduction - Inventory is considered to be a major cause of cost and source of bad quality. When Inventory is high, it hides all the problems like water hides all rocks during high tide. Inventory is controlled in a JIT workplace by Visual Controls. Excess or shortage is made visual by suitable markings in the workplace.
2. Take the defect to source – In JIT as the inventory is very less, defects produced are easily traced to their origins. And corrective actions are applied.
3. No demand no production – material should never be idle. Idle material brings about the doom of an organization
4. Pull as against Push system – In Pull System, production is controlled by the customers pull for the products while in conventional system, production is controlled by a plan made yhe organization anticipating the customers’ demand
5. Flexibility – a JIT company is highly flexible to the changes in the market or the customer preferences
WHY JIT? BENEFITS
1. Minimum inventory cost
2. Defect is taken to the source
3. Better quality
4. Zero breakdowns
5. Lower TPT
6. Reliable Delivery Schedule
7. Clear accountability
8. Total employee involvement
9. Higher productivity
TOOLS AND TECHNIQUES TO SUPPORT JIT
HOW? - TOOLS AND TECHNIQUES
1. T P M
2. SMED
3. Kanban
4. Group Technology
5. Single Piece Flow
6. Pokayoke
7. Andon Lights
8. 5s
TOTAL PRODUCTIVE MAINTENANCE
TPM or Total Productive Maintenance is an initiative in JIT to make the equipment highly efficient. Its objective is to achieve three zeros on every piece of equipment, zero defects, zero breakdown and zero accidents. In TPM maintenance and production are considered to be two wheels of a bicycle, which are inseparable and support each other. TPM addresses following areas on an equipment in order to achieve equipment effectiveness and efficiency
Seven big losses
1. Loss on account of breakdowns – when the machine is unable to respond to production needs due malfunction.
2. Loss on account of change of tools & adjustments – machine is stopped for changing or adjusting tools when the production process is on.
3. Loss on account of changing of dies & tools – setup changes for starting new variety of job
4. Loss on account of start up of equipment – time spent for warming up or make ready
5. Loss on account of minor stoppages – due to small snags between machines like a part getting stuck in a chute between two machines.
6. Loss on account of low speed – machine is being run slowly as at full speed some problems are experienced which may cause harm to product, machine or operator
7. Loss on account of defects and repair – time spent for rework
Eight pillars of TPM
1.Individual improvement for maximization of equipment efficiency. Individuals constantly improving themselves and all the equipment as a part of their culture
2. Establishing an autonomous maintenance System where the operator carries out certain checks and repairs according to a system, which do not call for special training. These jobs are like cleaning, checking oil levels, conditions of belts and gears, tightness of bolts and nuts etc. and carrying out repairs or exposing such problems.
3. Establishing a planned maintenance system by maintenance dept – carrying out planned maintenance jobs based on the inputs of autonomous maintenance and manufacturers instructions.
4. Education and training to increase operation and maintenance skills. Plan and implement training programs for proper use and maintenance of equipment.
5. Establishing a system to control equipment at initial stage (Production Engineering. dept. must design a maintenance free equip. at the design stage and must stabilize the operation of new equipment at the earliest). The feedback collected from production department, customers and service providers is built into the design of the product to eliminate problems later.
6. Establishing a quality maintenance system/program – a program to maintain the level of quality level achieved.
7. Establishing a system /plan for the maximization of efficiency of indirect departments like stores, purchase, HRD etc.
8. Establishing a safety and environment management system/plan to ensure the safety of people and equipment.
SINGLE MINUTE EXCHANGE OF DIES (SMED)
SMED is an initiative to reduce setup time to a single minute level. This is done by following the steps mentioned below
1. Segregate internal ‘I’ & ‘E’ activities 2. Perform ‘E’ activities externally This will straightaway reduce the set up time by about 30%!
3. Identify ‘A’ type ‘I’ activities and convert them into ‘E’ activities and ‘do’ as in previous step. See the result
4. Among the ‘I ’ identify those which can be done parallel and ‘do’.
5. Apply MISER on parallel and sequential ‘I’ activates [Eliminate – if you cant, reduce. - if you cant, improvise (by changing the method) - if you can’t, reduce to a an achievable target- if you can’t, simplify the current method.
6. Apply this step on ‘e’ activities also
7. Check the reduction in set up time and set a new target
8. PDCA till you reach single minute target
KANBAN
1. A Japanese concept to control inventory quantities at minimum level derived from the working of departmental stores in the US
2. Started by Toyota for the first time in their assembly plant
3. Kanban is a signal generally in the form of a card. Kanban is an inventory control tool in JIT. Conceptually it resembles a relay race where a baton is used to control the runners. Principle of the baton from relay race is incorporated in the concept of a two-bin system.
4. A kanban card indicates what item is needed, where it is needed, when it is needed and how it is to be delivered. This signal is delivered to the previous process by the process, which needs the items for production.
5. Kanban is a signal from a process to the previous process to supply parts
6. Previous process produces and supplies the kanban quantity and stops production. If needed sends kanban to the process previous for parts
7. Inventory in the entire value chain is controlled by this system
Pokayoke
Pokayoke is a Japanese word for mistake proofing. Inadvertent errors by people result into bad quality and or accidents. Concept of pokayoke eliminates such errors. Defects chart serves as a good source for pokayoke opportunities. Analysis of prioritized problems yields opportunities for pokayokes, which directly effect QCD performance of the organization.
Some examples of simple pokayokes are visual display boards, use of alarms, use of gadgets and change in method of performing work.
Andon
Andon is communication through lights in a work place. When the work place is lean and JIT, instantaneous communication becomes key to good performance.
Examples of Pokayoke are Traffic lights, lights indicating inventory position at production line, lights in workplace indicating the machine in trouble.
1. In the new competitive environment as the customer becomes choosy, keeps changing his tastes and demands variety to choose from mass production is inadequate for most of the products. In the days of Henry Ford the cost was the only criteria and customers were happy with an affordable price and there weren’t many suppliers. It was a seller’s market
2. The ratio quantity/variety determines the production system. For large ratio mass production is indicated. As the variety is increased and the ratio comes down we move towards batch production. As the variety further rises the batch becomes smaller and smaller to produce
3. But as the batch size becomes smaller than the EBQ the set up costs rise and production becomes uneconomical
4. If we reduce the setup cost/setup substantially we shall find that the batch quantity can be reduced without increasing the total inventory costs. The EBQ will come down and start approaching one, as the set up cost is further slashed down. As this happens we move towards a new production system called Just In time production system
WHAT IS JUST IN TIME?
1. JUST IN TIME IS A PRODUCTION SYSTEM – a combination of flow system and batch system
2. JIT is producing when the demand is placed on the system in minimum lead time
3. It is producing a variety of products just in time when they are demanded.
PRINCIPLES IN JIT
1. Inventory reduction - Inventory is considered to be a major cause of cost and source of bad quality. When Inventory is high, it hides all the problems like water hides all rocks during high tide. Inventory is controlled in a JIT workplace by Visual Controls. Excess or shortage is made visual by suitable markings in the workplace.
2. Take the defect to source – In JIT as the inventory is very less, defects produced are easily traced to their origins. And corrective actions are applied.
3. No demand no production – material should never be idle. Idle material brings about the doom of an organization
4. Pull as against Push system – In Pull System, production is controlled by the customers pull for the products while in conventional system, production is controlled by a plan made yhe organization anticipating the customers’ demand
5. Flexibility – a JIT company is highly flexible to the changes in the market or the customer preferences
WHY JIT? BENEFITS
1. Minimum inventory cost
2. Defect is taken to the source
3. Better quality
4. Zero breakdowns
5. Lower TPT
6. Reliable Delivery Schedule
7. Clear accountability
8. Total employee involvement
9. Higher productivity
TOOLS AND TECHNIQUES TO SUPPORT JIT
HOW? - TOOLS AND TECHNIQUES
1. T P M
2. SMED
3. Kanban
4. Group Technology
5. Single Piece Flow
6. Pokayoke
7. Andon Lights
8. 5s
TOTAL PRODUCTIVE MAINTENANCE
TPM or Total Productive Maintenance is an initiative in JIT to make the equipment highly efficient. Its objective is to achieve three zeros on every piece of equipment, zero defects, zero breakdown and zero accidents. In TPM maintenance and production are considered to be two wheels of a bicycle, which are inseparable and support each other. TPM addresses following areas on an equipment in order to achieve equipment effectiveness and efficiency
Seven big losses
1. Loss on account of breakdowns – when the machine is unable to respond to production needs due malfunction.
2. Loss on account of change of tools & adjustments – machine is stopped for changing or adjusting tools when the production process is on.
3. Loss on account of changing of dies & tools – setup changes for starting new variety of job
4. Loss on account of start up of equipment – time spent for warming up or make ready
5. Loss on account of minor stoppages – due to small snags between machines like a part getting stuck in a chute between two machines.
6. Loss on account of low speed – machine is being run slowly as at full speed some problems are experienced which may cause harm to product, machine or operator
7. Loss on account of defects and repair – time spent for rework
Eight pillars of TPM
1.Individual improvement for maximization of equipment efficiency. Individuals constantly improving themselves and all the equipment as a part of their culture
2. Establishing an autonomous maintenance System where the operator carries out certain checks and repairs according to a system, which do not call for special training. These jobs are like cleaning, checking oil levels, conditions of belts and gears, tightness of bolts and nuts etc. and carrying out repairs or exposing such problems.
3. Establishing a planned maintenance system by maintenance dept – carrying out planned maintenance jobs based on the inputs of autonomous maintenance and manufacturers instructions.
4. Education and training to increase operation and maintenance skills. Plan and implement training programs for proper use and maintenance of equipment.
5. Establishing a system to control equipment at initial stage (Production Engineering. dept. must design a maintenance free equip. at the design stage and must stabilize the operation of new equipment at the earliest). The feedback collected from production department, customers and service providers is built into the design of the product to eliminate problems later.
6. Establishing a quality maintenance system/program – a program to maintain the level of quality level achieved.
7. Establishing a system /plan for the maximization of efficiency of indirect departments like stores, purchase, HRD etc.
8. Establishing a safety and environment management system/plan to ensure the safety of people and equipment.
SINGLE MINUTE EXCHANGE OF DIES (SMED)
SMED is an initiative to reduce setup time to a single minute level. This is done by following the steps mentioned below
1. Segregate internal ‘I’ & ‘E’ activities 2. Perform ‘E’ activities externally This will straightaway reduce the set up time by about 30%!
3. Identify ‘A’ type ‘I’ activities and convert them into ‘E’ activities and ‘do’ as in previous step. See the result
4. Among the ‘I ’ identify those which can be done parallel and ‘do’.
5. Apply MISER on parallel and sequential ‘I’ activates [Eliminate – if you cant, reduce. - if you cant, improvise (by changing the method) - if you can’t, reduce to a an achievable target- if you can’t, simplify the current method.
6. Apply this step on ‘e’ activities also
7. Check the reduction in set up time and set a new target
8. PDCA till you reach single minute target
KANBAN
1. A Japanese concept to control inventory quantities at minimum level derived from the working of departmental stores in the US
2. Started by Toyota for the first time in their assembly plant
3. Kanban is a signal generally in the form of a card. Kanban is an inventory control tool in JIT. Conceptually it resembles a relay race where a baton is used to control the runners. Principle of the baton from relay race is incorporated in the concept of a two-bin system.
4. A kanban card indicates what item is needed, where it is needed, when it is needed and how it is to be delivered. This signal is delivered to the previous process by the process, which needs the items for production.
5. Kanban is a signal from a process to the previous process to supply parts
6. Previous process produces and supplies the kanban quantity and stops production. If needed sends kanban to the process previous for parts
7. Inventory in the entire value chain is controlled by this system
Pokayoke
Pokayoke is a Japanese word for mistake proofing. Inadvertent errors by people result into bad quality and or accidents. Concept of pokayoke eliminates such errors. Defects chart serves as a good source for pokayoke opportunities. Analysis of prioritized problems yields opportunities for pokayokes, which directly effect QCD performance of the organization.
Some examples of simple pokayokes are visual display boards, use of alarms, use of gadgets and change in method of performing work.
Andon
Andon is communication through lights in a work place. When the work place is lean and JIT, instantaneous communication becomes key to good performance.
Examples of Pokayoke are Traffic lights, lights indicating inventory position at production line, lights in workplace indicating the machine in trouble.
