Conclusiones parciales

When talking about Lean, this method of classification is surely the most famous and common because it was developed directly by Toyota. In fact, this method helps staff find the root causes of waste by analyzing the flow of the production or service implementation process. The seven relevant types of waste are:

• Overproduction or asynchrony – producing too much, too early or too late to meet the customer’s demand;

• Inventory – raw material, work in process (WIP) and finished products stored;

• Motion – unnecessary movement of the body;

• Defectiveness – non-conforming products and services in general;

• Transportation – unnecessary movement of products between processes;

• Overprocessing – processing beyond what the customer requires;

• Waiting – having to wait before commencing the next activity.

MATERIAL,

- each wrong method that introduces waste

Fig. 2.1 Lean wastes and the 4M

2.3 Classifying the Types of Waste 19

2.3.3.1 Overproduction or Asynchrony

Overproduction is the biggest problem our manufacturing and service industries have to fight; overproducing means, quite simply, producing an amount of products that exceeds the demand too soon or too fast. To begin, a very simple consideration, typical in the manufacturing industry, can be taken into account:

Overproducing means producing when there is no customer order.

Many managers think that, really, all those products stored in the warehouses will eventually be bought, following the forecasts developed, for example, by an MRP. But can the company be sure that these orders will arrive? In the meantime, money has been spent and room taken up, without even mentioning the possibilities of obsolescence, theft, damage and so on. Overproducing leads to many negative consequences, among which are:

• Increase in inventories (second waste);

• The production process slowing down;

• Reduction of planning flexibility;

• Increase of indirect cost such as transport, inspections, and so on.

The reasons for overproduction are often related to:

• Production of oversized economical lots;

• Producing before/after the demand;

• Low speed of setups;

• Creating inventories to make up for defectiveness;

• Unnecessary staff in a process;

• Too many or too fast machines.

The staff can use a simple checklist like the one in Table2.1 to analyze the activity flow and estimate overproduction. This checklist was developed for a Table 2.1 A typical checklist to evaluate excessive production

Overproduction assessment Process: Auditor: Date

# Description of waste Yes No Waste evaluation^a Cause

1 A production control is implemented 2 Production system is balanced

3 Production is synchronized according to schedule 4 Defects within the processes

5 Manual assistance is needed 6 Adequate machine capacity 7 FIFO is applied

Total

a0¼ evident uncontrolled waste; 1 ¼ evident waste, no improvements; 2 ¼ reduced waste, improvements ongoing; 3¼ reduced waste, continuous workshops, positive performance indicators; 5¼ waste eliminated, process stabilized, positive indicators for at least 6 months

specific company, thus the criteria are not exhaustive and should be modified according to the type of organization.

It is interesting to point out that in the evaluation system, the organization pointedly did not include four points, so as to decisively separate a category managed averagely from a best practice performance.

Basically, overproduction can be eliminated by balancing capacity and work-load. Some Lean tools described in Chap.6can be used:

• SMED;

• Production leveling or Heijunka;

• One-piece flow cells.

Overproduction is also present in the service industry and public administration.

This might seem unlikely because there has been a great deal of talk about produc-tivity increase and public employment over the past few years, but low producproduc-tivity and overproduction can cohabit quite peacefully. How often do customers complain about long waiting lists and queues? Among the many obstacles there will probably be unnecessary parts of processes as well as balancing problems.

Example of Overproduction in Service Industry. A hospital department sys-tematically receives medical reports late with diagnostic processes that have been completed but were never requested.

In a local administration department a document may have to wait days to be signed by a director, even though a signature is not legally necessary and was never requested by anyone. This slows down the entire process.

2.3.3.2 Inventory

Inventory is the typical waste that, in manufacturing, is linked to overproducing.

Inventory is any product or raw material that has been stored within or outside the organization for a certain period of time.

Stock can thus be made up of raw material, semi-finished products or finished products; if they represent products waiting to be processed they become WIP. In the service industry the concepts of WIP and stock can also be applied; a pharmacy department inside a hospital will probably be more familiar with these concepts, but an office inside a city council that offers several types of permits and licenses may not immediately pinpoint WIP in its business. In service, as in manufacturing, WIP could be the amount of emails sent by customers/citizens that need to be answered by the office, rather than the requests the department has to evaluate, or the number of patients awaiting chemotherapy. The best way to discover where this waste lurks is to look where products tend to accumulate, and then ask oneself why so much stock piles up. The following are among the most frequent causes:

• Long changeover times;

• Producing big “economic” lots (Shish-Kabob);

2.3 Classifying the Types of Waste 21

• Early production;

• Bottlenecks in the production/service implementation flow;

• Parts of the process that create are inefficient or create defects;

• Processes at the beginning are quicker than those nearer to the end;

• Accepting that excessive inventory cannot be avoided because it means to immediately deliver to the customers.

This last cause is very important when attempting to install a Copernican revolution within the organization; the staff needs to realize and believe that excessive inventory can be eliminated.

Excessive inventory hides problems, it does not solve them.

The paradox for, thankfully very few, organizations is that excessive inventory can help improve assets and thus improve funding by banks. Although this might have been the case in the first years of the new millennium, but now, after the last financial crisis, external investors will surely understand what excessive stock really means. The traditional Lean methods to remove excessive inventory are:

• Better balancing activities;

• U-cells, group technology;

• Quick changeover operations;

• Pull production by using Kanban.

Staff may use a checklist like the one illustrated in Table2.2to analyze activity flow and measure stock. This checklist was developed for a specific company, thus the criteria are not exhaustive and should be modified according to the type of organization.

The third point of the checklist also implies safety at work and performance that integrates every system for Business Excellence.

Table 2.2 A typical checklist to evaluate inventory Inventory assessment checklist

Process: Auditor: Date

# Description of waste Yes No Waste evaluation^a Cause

1 Lots on shelves or on floor

2 Shelves and stock on the floor take up room 3 Product stacks block staff and machine access 4 WIP among process activities

5 WIP among workers’ activities 6 How easy is visualizing WIP quantity?

Total

a0¼ evident uncontrolled waste; 1 ¼ evident waste, no improvements; 2 ¼ reduced waste, improvements ongoing; 3¼ reduced waste, continuous workshops, positive performance indicators; 5¼ waste eliminated, process stabilized, positive indicators for at least 6 months

2.3.3.3 Motion

Wasting time may also refer to the movements of workers. When observing production or service implementation many activities without value added can be noticed: workers looking for tools that are not in their workplace, employees that need to move to be able to load data onto software, workers moved from one department to another to stand in for lack of qualified staff, and so on. Among the causes are:

• Poor layout design;

• Workers with lack of skills and/or poor training;

• Poor staff involvement;

• Increase in staff or work hours;

• Lack of order and cleanliness;

• Activities performed in isolated areas.

To remove unnecessary employee movements the following changes need to be made:

• Gradually move towards production flow;

• Improve workers’ skills and/or training;

• Increase awareness concerning movements;

• Set in order workplace (5S);

• Design U-shaped cells;

• Review instructions and procedures.

Table2.3is an example of waste type assessment.

Table 2.3 Typical checklist to assess waste due to motions Workers’ movements assessment checklist

Process: Auditor: Date

# Description of waste Yes No Waste evaluation^a Cause

1 How far the worker walks 2 Does the worker turn around?

3 Worker’s sideward movements 4 Does the worker have to bend over?

5 Left of right hand not being used 6 Setups that require a lot of movement

7 Repeated movements that have not been standardized 8 Too fragmented operations

Total

a0¼ evident uncontrolled waste; 1 ¼ evident waste, no improvements; 2 ¼ reduced waste, improvements ongoing; 3¼ reduced waste, continuous workshops, positive performance indicators; 5¼ waste eliminated, process stabilized, positive indicators for at least 6 months

2.3 Classifying the Types of Waste 23