Manufacturing System Analysis Lean Production

Published Date: 02 Nov 2017

"Today, manufacturing companies and plants must operate efficiently and effectively to remain competitive in both cost and time, in the global economy. One of the general approaches that have made this concept successful is lean production.

Lean production refers to do more work with fewer resources. It is an adaptation of mass production in which work is accomplished in less time, in a smaller space, with fewer workers, and with less equipment, and yet achieves higher quality levels in the final product.

The term "Lean Production" was coined by researchers in the International Motor Vehicle Program at the Massachusetts Institute of Technology to describe the way in which production operations were organized at the Toyota Motor Company in Japan during the 1980s." (Groover, pp. 60, 786)

In research report the efforts are to provide brief and concise preamble as well as detail knowledge of the Lean production and implementation to the manufacturing industry.

Table of Contents

1. Manufacturing

1.1. Manufacturing Process

"Manufacturing is defined as the application of physical and chemical process to alter the geometry, properties, and/or appearance of a given starting material to make parts or products; manufacturing also includes the jointing of multiple parts to make assembled products.

The processes that accomplish manufacturing involve a combination of machinery, tools, power, and manual labour, as shown in the above figure. Manufacturing is almost always carried out as a sequence of operations." (Groover, pp. 39-40)

"Manufacturing is also defined as the production of goods for use or sale using labour machines tools, chemical & biological processing, or formulation." (Wiki)

1.2 Methods of Manufacturing

The following are the various different types and methods for manufacturing systems.

Mass production

Just In Time manufacturing

Lean Production

Flexible manufacturing

Mass customization

Agile manufacturing

Rapid manufacturing

Putting-out system

English system of manufacturing

American system of manufacturing

Soviet collectivism in manufacturing

Prefabrication / Fabrication

Packaging and labelling

Computer Aided Manufacturing

Virtual Manufacturing

Nano Manufacturing

Source: (Wiki)

2. Lean Production

"Lean production means operating the factory with the minimum possible resources and yet maximizing the amount of work that is accomplished with these resources. Resources consist of workers, equipment, time, space and materials. It also refers to completing the products in the minimum possible time and achieving a very high level of quality, to achieve customer satisfaction. In short, lean production means doing more with less, and doing it better." (Groover, p. 61)

Lean production works by eliminating the wasteful activities so that only the value adding and auxiliary activities are performed. When it is being achieved, it results in reduction of resources required for the manufacturing process, the work is completed in less time and higher quality standards are presented in the final product.

Ohno developed a number of tools for operating his production format in a systematic framework. He also identified major seven forms of waste in manufacturing that requires to be eliminated for better efficiency which builds the foundation for Lean Production systems. Ohno’s disciples improved his contributions into what is now known as the Toyota Production System. The types of wastes are as:

Production of defective parts

Production of more than the number of items needed (Over production)

Excessive Inventories

Unnecessary processing steps

Unnecessary movements of people

Unnecessary transport and handling of materials

Workers waiting

3. Lean Production - Building Blocks

With the intention of reducing the waste in manufacturing and to have maximum output with fewer resources, Lean production uses many tools which are known as building blocks. The successful implementation of these tools helps to improve the production capacity, also the sequence of implementation to be taken into account in order to have best results.

The ingredients of the Lean Production System can be visualized as a house with a foundation and two pillars holding up a roof. Further, Shingijutsu sense as:

The two pillars of the house, arguably the most important elements, are Just in Time and jidoka / autonomation. The former emphasizes operating with the minimum resources to consistently deliver the product or service. The latter, which is also known as line-stop authority or inline quality assurance, is a system for confirming quality and detecting abnormalities before they can pass further downstream in the process.

The foundation of a global production system incorporates the elimination of waste, which reduces costs and levels production. It is important that Level production is to be achieved to make just-in-time production possible.

The house roof represents the system's goals, the attainment of world-class performance: satisfying customers with high-quality, low-cost products or services that are provided by employees who work safely and enjoy high morale. In detail, providing goods or services the right way.

Source (J. Black)

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Figure: The Global structure of Lean Production System

The main Blocks of Lean production are:

3.1 Just in time delivery of parts:

The manner in which parts are delivered to the downstream workstation immediately before that part is needed at the station. Thus minimizes the amount of work in process inventory between stations and also produce high level of quality in parts that are manufactured.

3.1.1 Pull System of Production Control:

Order to make and deliver parts at each workstation in the production sequence comes from the downstream station that uses those parts. Before the downstream station is about to have parts shortage, it generates request to the upstream station well in advance for the supply. This practice is used throughout the production facility.

3.1.2 Kanban:

Kanban system of production control is based on the use of cards that authorizes at first the parts production followed by parts delivery in the plant. The conventional Kanban system comprises of two cards (1) production Kanbans and (2) transport Kanbans. The former (P-Kanban) authorizes the upstream station to produce the batch of parts, it also prevents the upstream to produce more than mentioned quantity. The later card (T- Kanban) authorizes the transportation of the parts to the downstream station. Modern implementation of the Kanban is in the form of Bar code system and automated data collection technologies to reduce the transaction time and increase efficiency of the job shop.

3.1.3 Set up Time and Batch Size Reduction:

In batch production process various engineering techniques are used in order to minimize the time of change over from one setup to the next. This results in small batch sizes and helps in reducing the amount of work in process in the production facility. Reduce set up time permit smaller batches and lower work in process levels. There are two elements which reduce the set-up time depending upon the nature and requirement. Internal elements can only be done while the production machine is stopped while external elements do not require the machine to be stopped. The internal element gets higher priority as they determine the time in which machine will not be contributing towards production. There are several techniques used for reducing setup time. The setup time reduction methods are devised by Japanese.

3.1.4 Stable and Reliable Production Operation:

This process consists of

Production levelling

On-time delivery

Defect free components and materials

Reliable production equipment

Workforce that is capable, committed and cooperative

Dependable supplier base

3.2 Automation

The main purpose is that machine operates autonomously as long as they are functioning properly and machines and processes are designed to prevent errors.

3.2.1 Stop the process when something is wrong:

Production machines are designed to stop automatically when a defective part is made, or the required quantity has been completed, or some abnormal operation occurs.

3.2.2 Error Prevention:

In order to prevent from errors low cost devices and design features at each work stations are introduced. Common errors in production are omitting processing or assembly steps or use of improper tool.

3.2.3 Total Productive Maintenance

This includes preventive maintenance and other procedures to avoid machine breakdowns that interrupt production operations. The main feature is that worker at the machine perform minor repairs and maintenance procedures.

3.3 Worker Involvement:

Workers in Lean environment assigned great responsibilities and are trained to be more flexible in the works they performed. They exhibit team work in order to cope up the problems faced by the unit.

3.3.1 Continuous Improvement (Kaizen):

This involves an unending search for ways to make improvements in products and manufacturing operations. It is accomplished by workers strong co-operation to develop solutions to production and quality problems.

3.3.2 Total Quality Management (TQM):

This process is used to continuously improve all areas of production. TQM is an integral part of all the processes involved and ensures the quality assurance as well as quality control of the parts and products.

3.3.3 Visual Management and 5S

The main idea of visual management is that the status of the work situation should be evident just by looking at it. If something is wrong, this condition should be obvious to the observer, so that corrective actions can be taken immediately. This methodology enables the visibility throughout the plant and encourages continuous improvement. The steps in 5S provide additional means of implementing visual management to provide a clean, orderly and visible work environment that promotes high morale among workers and also encourages continuous improvement. The 5 steps are (1) Sort, (2) Set in order, (3) Shine, (4) Standardize, (5) Self- discipline

Table: The elements of Just-In time, worker Involvement and Automation in Lean Production

Just-In Time Production

Worker Involvement

Automation

Pull system of production controls using Kanbans

Set-up time reduction for smaller batch sizes

Production Leveling

On-time Deliveries

Zero Defects

Flexible workers

Continuous Improvement (Kaizen)

Quality Circuits

Visual Management

The 5S system

Standardized work procedures

Participation in total productive maintenance by workers

Stops the process when something goes wrong

Prevention of over production

Error prevention and mistake proofing

Total Productive maintenance for reliable equipment

3.4. Lean Production Comparison with Mass Production

The following is the comparison of Mass production with a manufacturing system following Lean production system. The idea is to make manufacturing more effective in terms of time and cost. Thus enable to enhance the efficiency of the manufacturing unit/plant.

Table: Comparison of Mass Production and Lean Production

Mass Production

Lean Production

Inventory Buffers

Just-In-Case Deliveries

Just-In-Case Inventory

Acceptable Quality Level

Taylorism (workers are told what to do)

Maximum Efficiency

Inflexible product System

If it not broke, Do not fix it

Minimum Waste

Just-In-Case Deliveries

Minimum Inventory

Perfect First-Time Quantity

Worker Teams

Worker Involvement

Flexible Product System

Continuous Improvement

Source: (Groover, p. 786)

4. Implementation of Lean Production

4.1.   Toyota Production System

In order to grasp the knowledge about world-class performance in production systems, it is essential to have comprehensive awareness of manufacturing methodologies mainly those which are efficient in time delivery of the product. Japan in particular has pioneered systems that, if used correctly, can increase output while minimizing input. The Toyota Production System defined by Ohno is:

The basis of the Toyota Production system is the absolute elimination of waste.

Cost reduction is the goal.

After World War II, our main concern was how to produce high-quality goods. After 1955, however, the question became how to make the exact quantity needed.

"TPS is a production system which is a quantity control system, based on a foundation of quality, whose goal is cost reductions, and the means to reduce cost is the absolute elimination of waste."

The Two Pillars of the TPS

Ohno describes the TPS as consisting of many techniques that are designed to reduce the cost of manufacturing. The method of reducing cost was through the elimination of waste. TPS, is built on two pillars.

Just In Time

The first pillar is Just In Time (JIT). This is the technique of supplying exactly the right quantity, at exactly the right time, and at exactly the correct location. It is quantity control.

Jidoka

The second pillar is jidoka. This is a series of cultural and technical issues regarding the use of machines and manpower together, utilizing people for the unique tasks they are able to perform and allowing the machines to self-regulate the quality.

4.2. Main Features of Toyota Production System

Reducing the waste as much as possible.

Less movement of the producing labour, leads to less time in producing (just in time).

Every step of the production can be checked, go smoothly and without any mistakes due to (jidoka).

Good quality.

Items properly organized in ascertain way.

Increasing efficiency and productivity.

More accurate and reliable information.

Gives the user information that the company need them to know.

Tracking and reporting of the user performance.

Use of Kanban system, to produce the minimum quantity of parts needed to feed to the next process in sequence.

4.3. Limitations and Issues faced By Toyota

Difficult, high cost to implement.

To implement this system they need to dismantle previous systems, train employees

how to use it.

In lean manufacturing they keep small amount of inventory in hand, so they need a

supplier that they fully trust not to interrupt or delay the supplies and

always stay on schedule.

Ware house management system is costly as well as complex to use.

Takes months to be fully implement and ready to use.

Reduce the possibility for the user to get more explanation if he

didn’t understand.

4.4. Solution to Limitations

In order to have a better solution of these limitations a continuous improvement in the system is necessary.

Reduce complexity of using a system, by applying well defined, easier interface.

Reduce implementation cost, by removing unwanted or unneeded features of the system.

5. SWOT Analysis for Toyota

Strength

Weaknesses

Internal

Brand Name, Toyota Production System

Production in US & Japan only

Toyota Motors has the right mix of products for the market that it serves

Fluctuating economic & political condition of USA & Japan

World 2nd Largest Car maker with *78 Million units

Operational efficiency

Efficient Manufacturing Approaches

High Cost of training & retaining labour

Marketing Techniques

 

Shorter Lead Time

 

External

Opportunities

Threats

Advance technologies

Competitors

Hybrid vehicles as fuel prices increases

Economic Factors

Target Urban Youth Market

Tightening emission standards

Asian Market & new Models

Rising prices in Global

(Toyota - SWOT)

Case Study

Forming cylinder cells

Company: Regina-based Brandt Engineered Products Ltd., boasts the largest and best-equipped machine shop in southern Saskatchewan. Brandt Engineered Products Ltd is a recognized and leading provider of engineered-to-order equipment and machinery for heavy industry throughout North America.

Product: Hydraulic cylinders

Challenge: Increase annual production while reducing customer lead times and internal cycle times.

Project Objectives:

Reduce current lead-time from 23 days;

Reduce input costs per cylinder;

Eliminate delays due to departmentalized production processes.

Primary Actions:

Measured all component parts in terms of time to produce, distance travelled, and machinery/processes utilized to produce these parts;

Designed and implemented a manufacturing cell to include all possible machines including milling, lathe, welding and assembly.

Lesson Learned and Results:

Required production space reduced by 30 percent;

Travel distance between processes reduced by 85 percent;

Lead time for first off production reduced by 80 percent.

TUPPAS - Lean Manufacturing Software

Lean manufacturing software provides a method of boosting production and distribution efficiency. Manufacturers who can better match production to demand, reducing inventories, raw materials and finished goods lower their costs and are better able to respond more quickly to market changes. Lean Manufacturing Software has the following modules of operation:

Production Scheduling

Production Reporting

OEE (Overall Equipment Effectiveness)

Inventory

Total Quality Management

Purchasing

Downtime Reporting

Financials & Accounting

Defect Tracking

Closed Loop Manufacturing/Green Manufacturing

Project Management

CRM Customer Relationship Management

KPI Software

Cost Accounting/Job Costing/Product Costing

Business Apps

Material Requirements Planning

Job Tracking

Scrap Reporting

This process provides the maintenance and support for Lean Manufacturing Software system, and clients pay a monthly fee. The software can be highly customized, as Tuppas has developed a framework tool which allows the system to be tailored to each client's needs. 

Conclusion

Ten Lessons for a Lean, World-Class Production System

People, not technologies, are the key to world-class performance.

If you are going uphill and taking one step at a time, you are headed in the right direction.

Without knowledge and understanding of the Toyota Production System, you are a small ship in heavy fog without a reliable compass.

Employee involvement is the foundation. Without that in place, you can't build a lean, world-class production system.

The methods, revolutions, and thresholds that must be crossed to compete in the global market cannot be accomplished from the bottom up. They have to start from the top down.

The goal of a world-class production system can only be achieved with a Just in Time (JIT) Promotion Office to help promote the process.

If you're not simple, you can't be fast, and if you aren't fast, you can't win.

Hiring consultants to come to your company, collect data, and feed it back to you with a strategy that requires you to spend money, add people, and buy expensive machines and equipment means one thing: You are really stupid.

In measuring progress toward the vision, metrics must be few, simple, meaningful, and directly linked to visual targets in the workplace.

The greatest opportunities to eliminate waste are in the corporate "wasteland:" offices, engineering floors, and service industries.