Appunti sulle lezioni del corso di Production Management - Secondo Parziale

La tecnica Kanban

1. TQM: TOTAL QUALITY CONTROL

2. SEKKEI KAURI

3. TPM

4. JUST IN TIME (KANBAN)

KANBAN

Gli inventari sono uno spreco di denaro. Sono necessari quando il fornitore e i clienti non condividono gli stessi obiettivi (prodotti). Più alto è il livello dell'acqua, più mi sento al sicuro.

Problemi: uso più "rocce" quindi inventario per mantenere il livello dell'acqua. MA, questo è OPPOSTO ALLA TECNICA GIAPPONESE. Infatti, KANBAN FUNZIONERÀ COSÌ: ho bisogno di DIMINUIRE il livello dell'acqua, le rocce emergeranno e distruggerò tutte le rocce (problemi). Quindi, anziché investire in scorte, è meglio investire in macchinari, produzione e capacità.

Esempio:

ROCCE: sono problemi

ACQUA: livello di inventario

LA TECNICA KANBAN HA 3 PRINCIPALI PRINCIPI:

1. È UNA TECNICA DI "PULL". È un modo per gestire la catena di approvvigionamento, considerando il mercato. Nell'approccio Kanban, l'Effetto Frusta viene mitigato dalla capacità di produzione.

2. È VISUALE. Consente la gestione visiva della produzione attraverso regole semplici. Basta dare un'occhiata al piano di lavoro.

1. Mailbox (supplier area) to point out (i.e. to signal) that“something” originated downstream consumption.
2. Production kanban is attached to an empty container withdrawn from the storage area and it is sent to the supplier area for processing.
3. As a result, a (new) full container (with the corresponding production kanban attached) is ready.
4. The full container is sent to the storage area.
5. The inventory level is again the same as before downstream consumption took place

Criticism: Zero inventory is unrealistic.

No SS, No Spec. Stocks, BUT you cannot reduce to zero the cycle stocks.

Type of stocks:

• Cycle Stocks
• Safety Stocks
• Speculative Stocks

2 customers —> 2 customers require 2 different Kanban types

The problem arises in the mailbox.

If you receive 2 orders/Kanbans coming from different customers but your production capacity allows you to produce just 1 item per time —> PRIORITISE THE MAIL BOX: It has a specific name: DISPATCHING.

This happens when you have a QUEUE.

PRIORITISING —> DISPATCHING

When we talking about dispatching we mean picking the next one and leave all the other without priority.

SEQUENCING: you have to assign a priority to each Job in order to decide the order itself.

When we talking about sequencing we mean picking the next one and giving priority to the whole line of that job.

FIFO (First In, First Out) is the EASIEST way of sequencing a queue.

So whenever you have more than 1 flow (problem of prioritising) BUT this means RULES and its’ in contrast with the rule of KANBAN “no rules - visual model”

THE KANBAN BOARD

When the supplier work-centre is able to produce more than one product (i.e. very often) a problem arises: How can the supplier work-centre manager prioritise Kanban (of different part numbers) to select the next lot to be processed (i.e. for dispatching purposes)?

Instead of using the kanban mailbox, the kanban board has to be introduced—>To

• GREEN ZONE: Area of idleness and peacefulness. "Do not produce anything".
• WHITE ZONE: Area of planning. "Produce to minimise set-ups etc."
• RED ZONE: Area of urgency and hurry. "Produce as soon as you can, to avoid downstream stock-out"

JIT KANBAN MANAGEMENT

The Kanban rules

1. No parts may be made up stream (in the supplier area) unless there is a production kanban authorising it. Supplier comes to halt rather than making parts not yet asked for- Workers may do maintenance or work on improvement projects when there are no production kanban in the mailbox / on the board
2. There are precisely one conveyance kanban and one production kanban for each container. The number of containers (with kanban) per part number is a carefully considered management decision.
3. Only standard containers may be used, and they always are filled with

the prescribed (small) quantity – nomore, no less.- With such careful control of quantities per container, as well as the number of containers NO per part number,inventory control is simple

KANBAN MANAGEMENT: REMARKS

1. Kanban management is simpler than “push” (MRP) management.- It does not require detailed forecasts and/or a lot of information(e.g.BOMs)
2. The number of production/conveyance Kanbans inherently limit work in process.
3. Bullwhip effect is avoided- The“exact” amount consumed (downstream) is withdrawnand the exact amount withdrawn is produced (upstream)- The downstream consumption immediately (i.e. without delay) triggers production upstream.
4. Kaizen (improvement) is implemented by (progressively) reducing the number of Kanbans- This requires the Kanban board to be updated accordingly.- Kanbans are to be subtracted from the green zone.- This leads to reduce the inventory level.

Executive summary- Kanban (literally signboard) management is one

of the JIT-oriented (pull) techniques in the area of supply chain management useful to reduce (to zero) the overall inventory level.

According to Kanban, no parts may be made upstream (in the supplier area) unless there is a production kanban authorising it

Supplier comes to halt rather than making parts not yet asked for and workers may do maintenance or work on improvement projects when there are no production kanban on the board

Bullwhip effect is avoided, since the "exact" amount consumed (downstream) is withdrawn and the exact amount withdrawn is produced (upstream)

Kaizen is implemented by (progressively) reducing the number of Kanbans, which leads to reduce the inventory level

REVOLUTION AND CHANGES IN THE INDUSTRY

TAYLOR: Split the jobs in very tiny parts, so you do not need to be a craft man to do that. It is made possible to have low skilled workers.

FORD lowered the selling price of cars in order that everyone could afford the price of a Ford car.

CAR: before,

Owning a car was possible only for the richest families. Fiat factory in the '70s was working equal to Ford Industry. Fiat 127, only Black Color, very repetitive work. Now we can buy a traditional English motorbike or a German made camera and so on. But nowadays a lot of companies and industries died. The traditional "Made in Europe" companies have now been replaced by cheaper companies, that provide the same (or lower) quality but made "In SERIE". The "fuori serie" is an Italian coined word to describe special/expensive and customized products. It is in contrast with what is produced in lines by operators. (Lower skills and high degree of automation) DETROIT: The area is called RUSTY BELT. There used to be a lot of Car Industry factories but after the Japanese "invasion" of products, there was a disaster in the US market of cars. -> Nobody used to buy US car anymore. THE BASIS OF THIS REVOLUTION WAS THE WAY OF MANUFACTURING.

KAIZEN (Continuous improvement)

POLICY DEPLOYMENT

INVOLVEMENT AND ENGAGEMENT

The Japanese culture was really different from USA or EUROPE ones. For instance, the factories in EU and US were dirty, dark, defects were % parts per hundred (many factories closed) instead in Japan the factories were clean, light, comfortable environment, and % of defects were parts per millions.

1st thing to do: MEASURE THE PERFORMANCE of the Company.

—> the way you measure performances is relevant for STAKEHOLDERS.

CATEGORIES OF PERFORMANCES:

Quality

Costs

Volume

Delivery

Innovation

Safety

Motivation

Environment

1. Client: without client, no invoices, no cash inflow.

2. Operators: the employees. If the employees are unhappy, company could lose the good ones “the talents” Employees produce quality!

3. Shareholders: Are those who put their savings in a company.

4. Society: We don’t want to have an authority coming to our factory and protesting because of “polluting, and so

2nd important thing to do: MEASURE PRODUCTIVITY

It integrates costs and volumes

Productivity = output/input

1. OUTPUT: Production/ Volume
2. INPUT: Resources
• LABOUR: Direct/Indirect or External
• CAPITAL: Equipment and Stocks
• MATERIAL: Direct, Indirect, Energy

Loss definition: Losses = Opportunities

The losses are always a way to improve, an opportunity to understand.

Volume of the inputs of the process = Production Costs = sum of the money spent to create the output

Losses: difference between the amount of resources used in VALUE ADDED ACTIVITIES (OUTPUTS) and the resources used.

The yield of materials is very important.

MACHINES UTILISATION

OEE= OVERALL EQUIPMENT EFFECTIVENESS

MTBF= MEAN TIME BETWEEN FAILURE

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