Lean production (lean manufacturing) is an approach to the organization management that aimed at improving the quality of work by reducing losses.
This approach applies to all aspects of activity - from design and production to product sales.
Lean manufacturing principles (Lean system) were developed by Japanese companies in the late 1980s and early 1990s.
The aim of Lean approach is to reduce actions that do not add value to the product.
Lean production can be considered both as a philosophy, as a system, and as a tool like most Japanese approaches to the management. The principles of
the Lean system imply continuous long-term work to improve quality and reduce losses. A set of quality tools is used to achieve the goals. The lean
production principles implementation is carried out on the basis of the developed methods.
The lean production principles
It is necessary to understand the principles of Lean Manufacturing in order to implement it. They are quite simple by themselves, but their
implementation requires a lot of effort from the organization.
The basic principles of the Lean system can be formulated as follows:
You should determine what creates the value of the product from the point of view of the end user. It can be to perform many actions in an
organization that are not important to the customer. If an organization exactly knows what the customer needs that it can determine which processes
are focused on providing value to the consumer and which are not.
You should identify all the necessary actions in the production chain and eliminate losses. It is necessary to describe in detail all actions from
the moment of receipt of the order to the delivery of products to the customer in order to optimize the work and identify losses. It is possible to
identify potential opportunities for improving processes due to this.
You should rearrange the activities in the production chain so that they represent a work flow. Actions in processes must be arranged in such way
that there are no expectations, downtime or other losses between operations. This may require redesigning processes or applying new technologies. All
processes should consist of actions that add value to the product.
You should do only what the end user needs. The organization should produce only those products, and in such quantities as the end user needs.
You should strive for excellence by constantly reducing unnecessary actions. The implementation of a lean manufacturing system cannot be a one-time
event. It is necessary to constantly improve the work by searching for and eliminating losses if you have of this system.
7 types of Lean Production Losses
There can potentially be a large number of losses in any organization that lead to a decrease in work efficiency. These losses represent actions that
do not bring value to the end user. It will allow an organization to increase efficiency and thereby reduce the cost of products for the end user if an
organization identifies and eliminates such losses.
The task of an organization implementing a Lean production system is to reduce actions that do not give value. This will significantly reduce the
production cycle and the final cost of products.
Lean Manufacturing identifies 7 types of losses:
transportation – transportation of finished products and in-process inventory must be optimized in time and distance. Each move increases the risk
of damage, loss, delay, etc. and more importantly, the longer the product is moved, the greater the overhead costs. Transportation does not add value
to the product, and the customer is not ready to pay for it.
inventory – the more inventories are in warehouses and in production, the more money is "frozen" in these stocks. Inventories do not add
value to the product.
movements - unnecessary movements of operators and equipment increase the loss of time, which again leads to an increase in cost without increasing
the value of the product.
waiting – products that are in work-in-process and waiting for their turn to be processed increase the cost without increasing the value.
overproduction – this type of loss is the most significant of all. Unsold products require production costs, storage costs, accounting costs, etc.
technology – this type of loss is due to the fact that the production technology does not allow to realize all the requirements of the end user in
the product.
defects – each defect leads to additional costs of time and money.
The types of losses that Lean Manufacturing considers are the same as in the Kaizen approach. Sometimes another type of losses is added to the Lean
system – these are losses from incorrect placement of personnel. This type of loss occurs if the staff performs work that does not correspond to their
skills and experience.
Lean Manufacturing Tools
Lean manufacturing is a logical development of many management approaches created in Japanese management. Therefore, the Lean system includes a large
number of tools and techniques from these approaches, and often the management approaches themselves. It is quite difficult to list all the tools and
techniques. The composition of the used tools will depend on the conditions of the specific tasks of a particular enterprise.
The main management tools and approaches that are part of lean manufacturing tools are:
Just in Time is an approach to production management based on customer demand. It allows you to produce products in the right quantity at the right
time.
Kaizen is an approach to managing an organization based on continuous quality
improvement. Employees regularly and actively work to improve their activities in this approach.
5S is an improvement methodology that is part of the Kaizen approach. It allows you to reduce losses associated with
poor workplace organization.
Andon is a visual feedback system in production. It enables all employees to see the state of production, warns when
help is needed, and allows operators to stop the production process in case of problems.
Kanban is a system for regulating the flow of materials and products inside and outside the organization - with
suppliers and customers. It allows you to reduce losses associated with inventory and overproduction.
SMED (Single Minute Exchange of Die) is a system that allows you to reduce the time loss associated with the
installation of work pieces.
Standardization of work is an element of the Kaizen approach. It allows you to document processes, thereby creating a
basis for improving activities.
Poka - Yoke is a method for modeling errors and their prevention in production processes. It allows you to reduce the
losses associated with defects in production.
Many of these approaches and tools can be used separately, but their combination gives more significant results in the concept of lean manufacturing.
The combination of techniques, tools and approaches supports and enhances each other thereby the Lean system makes itself more flexible.
Lean manufacturing application Areas
Lean Manufacturing was used in automobile factories initially. The approach has been adapted to the conditions of various industries over time. Now,
you can find both industrial, large enterprises, and small enterprises and organizations in the service sector among the companies using lean
manufacturing.
The use of the Lean system can be found in such areas of activity as:
logistics (in this area, "Lean Manufacturing" became known as "Lean Logistics");
banking services;
trading;
information technology (in this area, the system is called "Lean Software Development");
construction (the lean manufacturing system is called "Lean Construction");
education;
medicine (in this area, the system is called "Lean Healthcare");
oil production.
The lean manufacturing approach requires some adaptation to specific conditions. Its application allows you to achieve a significant increase in work
efficiency and reduce losses in any organization.
ISO 9001:2015 Explanations. Interpretation of requirements. Implementation guide.