Skip to main content

What is Lean Manufacturing?

 Lean manufacturing is a system to eliminate waste from manufacturing process to increase benifit. Lean manufacturing focus on removing unwanted process, inventory that is not useful in production and add cost in manufacturing product. Main motto of Lean Manufacturing is to reduce the cost of product, reduce delivery time and improve quality of product.

Lean Manufacturing is first introduced in Toyota, Japan. Ohno Taiichi was a businessman and engineer is considered as father of Lean Manufacturing and he gave concept of removing of waste (this waste is term as Muda) from production system. He gave seven Muda that should be eliminate from production system.

Lean manufacturing is also know as Lean management or just Lean. Initially Lean was used in only manufacturing industries only but after analysing the advantages of this system, it is now widely used in IT industries, medical industries and even financial institutions. This topic is also included in Management syallabus.


Seven Muda(waste) in Lean Manufacturing:

  1. Over production
  2. Inventory
  3. Motion
  4. Defect
  5. Over processing
  6. Waiting
  7. Transportation

1. Over production:

Most of the manufacturing industries things that over production is good for them as when ever customer require they can provide material to customer, but it is considered as most common and serious waste for industries as this creates unnecessary inventory which is not of any use till any demand. There is also waste of all the resources required to made that extra production. This may also lead to shortage of another product as raw material consume to build over production of one part. There may be possibility that excess produce product may got outdated or obsolete, that result to scrap all excess material.

2. Inventory:

Excess Inventory is similar effect that we seen in over production. Over production is considered for the finish product where as excess inventory is considered for raw material and material in WIP. Excess inventory is considered waste as it include extra cost to keep inventory and maintain it. We need extra sources like manpower, space, preventive oils, etc to keep the material. If inventory is not kept properly then material gets rusty and to follow FIFO will become difficult. Excess Inventory also shows that material planning is not proper or systematic. Excess Inventory is just like investment that is not paying anything. Other disadvantages of excess Inventory, material may get obsolete and then complete batch will be scrap. If customer stop buying the product then also there is no use of the excess inventory. It is important that we do not accumulate excess inventory in the plant. 

3. Motion:

Excess motion of man or material will reduce production rate. Material should be arranged in such a way that employee should not move much to get the material to complete his task. 
For example if maintenance team is doing some repairing work on machine and he is going to take tools at maint. area from machine then his movement will increase and effectiveness to repair machine will reduce in place of this his all tool should be well arranged in a box. 
Excess motion of material is also waste as it unnecessarily increase the cycle time of product and hence reduce production. It also increase the maintenance cost of gadget on which material is moved( either automatic, using conveyors or by manually).
Excess motion for man increase the fatigue of the man and reduce the efficiency of man.
Process should be design in such a way that motion of man and material is minimum.

4. Defect:

Defect is one of the major waste which can easily visible and understood by everyone. Defect is any abnormalities that may cause non confirmation in the product, or we can say product is not produce as per customer requirement.  Defect can be differentiated into two type Rework and Scrap. Either product will rework or it gets scrap in both cases company resources will be waste. Defect increased the overall cost of the production of the product. If defect increase in production activity then other activities increase like paper work and rechecking frequency of product also increase.
Nature resources also waste if defect is generated as it consume raw material which is made from natural resources and it not turn into useful product for use. To reprocess rework extra manpower and energy is used. If material got scrap then landfill also increase.
Most importantly if defective product reach to customer we may loose the trust or even customer itself. Defect should be very less and every year there should be plan to reduce the defect in production of products.

5. Over processing:

Over processing means extra process or activity done on product which is not so useful. Over processing activities are those activities that doesn't add value to the product.
For example, colour the car from inside that is not used, as cover is to be mounted inside the car.
Over processing activities increase the cost of product as it require extra manpower, time and material. It also reduce the efficiency of employees as he focus more on non value added activities instead of value added activities. As over processing increase the cycle time of product manufacturing hence decrease overall production, as a result increase delivery time. 

6. Waiting:

Waiting is cause due to the effect of slow cycle of next operation. In a chain of production if first operation is waiting for next operation to complete, in that condition cycle time of complete chain will increase and hence production will reduce. Waiting may be due to man or machine. 
If man is not able to complete the task then extra manforce to be provide or upgrade the skill of man so that he can do faster or he may require some short of tools that make his work faster. 
Waiting is due to machine then that machine is known as bottleneck machine, to improve the production or reduce the waiting time cycle time of bottleneck machine should be improved or we may plan two bottleneck machine can be installed in place of one machine but in this condition make sure that previous machine will not become bottleneck machine.
Waiting time waste resources like electric power, reduce the efficiency of employees, if material is effected the temperature then material may also waste or reject.

7. Transportation:

Transportation means trasfer of material from one place to another, material may be raw material or finished goods. Transportation don't add value to the product but extra transportation increase the cost of product. There should be arrangment that will reduce the transportation of material. 
Most of the big companies are now a days focus on transportation, to keep in that in view they give space to vendors in their premises so that transportation of material produce by vendors will reduce, it also help them to get the material on time. Some build their plant near the availability of raw material so that transportation of raw material will reduce. 
Transportation also waste the nature resources like petrol, CNC gases, etc. Air pollution increase as polluted gases from trucks and other vehicles. It also increase the possibility to delay the delivery of product at right time.

We already discussed seven waste in lean manufacturing but one waste is added now a days i.e non- utilized talent.

8. Non - utilized talent:

Non utilized talent is hidden waste in manufacturing process. It means that employees are not working with their full potential either  because of the following reasons:
  1. They don't have work to do.
  2. They are working on uninterested project.
  3. Commanding seniors, lack of freedom to take decision.
  4. Insufficient trainings.
  5. Poor team work.
  6. Improper communication with employees.
  7. They are working on project below their potential.
It is important to give proper training and freedom to take decision so that production planning will be done in faster way and any abnormalities on the shop floor is easily handle. All above seven points should be eliminate and employees should be able to work with his or her full efficiency or potential.

To make process lean it is important to solve these eight waste from the system. These can be solve by using following methods here we give name proper description will be done next articles:
If possible first try to eliminate the waste. Is elimination is not possible then substitute with something else, if this also not possible provide some engineer control and in the end nothing works then provide industrial control.

If you wish we check and help to reduce waste from your system then please write as on mail. We will try our best to help you.

Comments

Popular Articles

What is FMEA

 FMEA is stand for Failure Mode and Effects Analysis. FMEA is a process analysis tool. FMEA is used to identify all the failures or potential failures that may occur in a process, before any physical error occur in the process and analysis consequences due to failures. It is one of the core tool of IATF16949 . Other core tool of IATF16949 are: APQP: Advance Product Quality Planning PPAP: Production Part Approval Planning MSA: Measurement System Analysis SPC : Statistical Process Control Type of FMEA: There are two type of FMEA: DFMEA (Design Failure Mode and Effects Analysis) PFMEA (Process Failure Mode and Effects Analysis) 1. DFMEA (Design Failure Mode and Effects Analysis): DFMEA is a methodology which is used to analyse the risk or failure during new product or process development, it also used during any change or modification in product or process. 2. PFMEA (Process Failure Mode and Effects Analysis) PFMEA is a methodology which is used to analyse risk or failure during manufact

What is PPAP?

  PPAP is stand for Production Part Approval Proces . PPAP is standard process in automotive and aerospace industries. It is basically written contact between supplier and customer about a product or process through which product will manufacture. It is output of APQP. Intresting thing about pronunciation of PPAP is that is not pronounced as P P A P, where as it is pronounce as P-PAP .   It is one of the core tool of IATF16949 . Other core tool of IATF16949 are: APQP: Advance Product Quality Planning FMEA: Failure Mode and Effects Analysis SPC : Statistical Process Control MSA : Measurement Systems Analysis You can read about above topic by clicking on them. PPAP is very important for supplier and manufacturer, to understand the requirement of customer and also helpful to the customer to know, that, how well product will produce through it's lifetime by manufacturer. PPAP is a risk identification and mitigation process used to provide evident to the customer that there is a relia

What is SPC?

SPC is stand for S tatistical Process Control.   SPC is a tool used for continuous improvement. SPC used to maintain quality by monitoring the process and well detect the possible occurrence of the error before it actually happened and we'll detective. It is one of the core tool of IATF16949 . Other core tool of IATF16949 are: APQP: Advance Product Quality Planning PPAP: Production Part Approval Planning MSA: Measurement System Analysis FMEA : Failure Mode and Effective Analysis   The SPC process is better than other quality tools because it is based on detection and prevention rather than the correction of problems after they have occurred, it means it help us to detect the fault or give indication before error actually occur, which means we can correct the process or the job size before any error occur in our job. It is real time process, so machine operator can easily identify the trend of the job and take corrective action before generation of any NG product. SPC is not only u

What is APQP ?

 APQP is stand for Advance product Quality planning. APQP is a process that is used satisfy product quantity as per customer requirements. APQP is not just a process but it is set of process or framework of process that are used while developing new product or new process. By APQP we ensure that new product or process should well established before product reach to the customer. APQP (Advance Product Quality Planning) is one of the five basic core tool of IATF 16959 . Other four core tools of IATF16949 are: PPAP : Production Part Approval Proces FMEA: Failure Mode and Effects Analysis SPC : Statistical Process Control MSA: Measurement Systems Analysis  Soon we will be writing about these four core tools. In this article we will concentrate on APQP only. There two aims of APQP   Firstly , To increase communication between different departments of the company specially R&D, production, logistics, sales, etc. Most of the work what R&D is doing, is not aware to other departments,

What is LPA?

  LPA is a stand for Layer Process Audit . LPA is Quality technique that focus on how well the process is working or following by the manufacturing Industry at the shop floor. LPA is not just an fault finding audit but it is a process improvement audit as it is audit where changes (Observation Closure) can be done during audit only. By LPA, rejection and other waste is reduced and  work towards continual improvement.  It is one of the important part of IATF16949 (Clause no. 9.2.2.3) and OEM customers (CSR) requirement.  LPA is not only confined with Quality department, rather it include all departments and all level of management and supervisor. Supervisor do LPA at their own function and frequency of doing may be weekly. Middle management do LPA at their function and other functions also but for them frequency of doing audit may be monthly. Senior management do LPA to any one function and frequency is quarterly.  LPA in one of the Audit where supervisor and operator learn about proce