A lean organization achieves its goals through the application of time-tested techniques and tools, backed by a firm philosophical foundation of continuous improvement and learning. Behind the lean paradigm are a set of management principles that when consistently applied, result in business success regardless of one’s industry.

What is Lean Management?

Traditionally, we expect management to be the function that is involved in the planning, organizing, directing and controlling resources to achieve organizational goals. In lean thinking, management is the systematic approach of enabling the organization to make its lean initiatives in a focused and efficient manner.

Most organizations fail to sustain their lean efforts due to lack of proper direction from management. The traditional approach of “control” does not work in a lean environment because it does not lend itself to the philosophy of empowering workers to find solutions to the business problems through observation, experimentation, and learning.

The old way of doing things sees managers as people who should provide all the answers to workers on the ground. In lean thinking, however, everybody works together with a clear focus on customer value and continuous improvement.

Lean Thinking Management Principles

The following 14 lean management principles which originated from Toyota provide the philosophical foundation required to achieve success in a lean system. Each has a set of tools that can be used to attain the organizational goals.

These tools are meant to assist a company in achieving results and should not replace a common sense approach to problem-solving. The application of lean tools must happen with the underlying principle in mind. In short, the theory drives the tool and not the other way round.

1. Long-term thinking

The most important factors for success are patience, a focus on long-term rather than short-term results, reinvestment in people, product, and plant, and an unforgiving commitment to quality.

—Robert B. McCurry, former Executive VP, Toyota Motor Sales

Lean thinking organizations have a clear vision of where they want to be in the future. They have a clear picture of what needs to be done to achieve these goals and do not get distracted by the expediencies of the moment. The first principle of lean management is: “Make decisions based on your long-term vision even if means making sacrifices in the short-term.”

The lean tools that drive this principle are:

Hoshin Kanri is a strategic planning tool that ensures the whole organization is aligned to a common goal and leaves little room for diversion. Everybody knows where the company’s direction and their responsibilities in achieving these goals.

Nemawashi is a consensus-based decision-making approach that reduces the time taken to achieve results. By the time a formal meeting is held to make a decision, all involved parties have been consulted and have made up their minds on where they stand on an issue.

2. Flow the Customer Value

This principle deals with identifying wasteful activities that do not add any value to the customer. After determining the wasteful activities, have efforts are made to either eliminate or reduce them. You then align all the other steps in a continuous flow which increases productivity, quality, safety, and morale. There is also a marked reduction in costs as it requires fewer resources for achieving the same results.

If some problem occurs in one-piece flow manufacturing then the whole production line stops. In this sense it is a very bad system of manufacturing. But when production stops everyone is forced to solve the problem immediately. So team members have to think, and through thinking team members grow and become better team members and people.

—Teruyuki Minoura, former President, Toyota Motor Manufacturing, North America

The lean thinking tools that support this principle are:

Jidoka means building in quality into machines or process to prevent mistakes that have an impact on quality. This tool aims at capturing and correcting errors before they affect the next operation.

Line balancing is used to ensure that equal amount of work passes through the process to avoid the bottlenecks that hinder smooth flow of value

Cellular manufacturing increases flow by consolidating all the prerequisite steps that are required to assemble a product in one place. It also reduces the amount of time used when sub-assemblies move from one station to another   

3. Produce at the rate of customer demand

“The more inventory a company has, the less likely they will have what they need” – Taiichi Ohno (Father of the Toyota Production System)

Overproduction means “producing faster or more than the customer is demanding.” It is one of the most costly forms of waste as it encompasses all the known wasteful activities in lean manufacturing. By producing at a rate as close as possible to the real customer demand, costs reduce as there is very little unsalable inventory in place.

The tools that support this principle are:

Kanban system is a signalling device that informs a process what to do next whether it is producing a new product or replenishing raw materials.

Takt time is a metric that determines the rate at which the end customer is demanding a product. All the processes must be synchronized with this rate to avoid non-delivery or over-production

4.Level the workload

In general, when you try to apply the TPS, the first thing you have to do is to even out or level the production. And that is the responsibility primarily of production control or production management people. Levelling the production schedule may require some front-loading of shipments or postponing of shipments and you may have to ask some customers to wait for a short period of time.

—Fujio Cho, President, Toyota Motor Corporation

As companies cannot always produce at the exact frequency of customer demand, production must be evened out across production facilities to ensure prompt delivery. The system works by accumulating a good number of customer orders and then scheduling them at even intervals. Levelling reduces the waste and strain of trying to build to an erratic order. The lean tool used to level the workload is:

Heijunka is the balancing of production to mitigate against the unpredictable spikes in demand that occur in a typical organization. Heijunka stabilizes the production process and ensures the optimal utilization of available resources

Heijunka Box

5.Quality right the first time

Mr. Ohno used to say that no problem discovered when stopping the line should wait longer than tomorrow morning to be fixed. Because when making a car every minute we know we will have the same problem again tomorrow.

—Fujio Cho, President, Toyota Motor Corporation

A fundamental tenet of lean thinking is that all methods must produce quality parts so that the end product to the customer is defect-free. This principle states that no process should produce, accept or pass on a defective part to the next step. Inspection is a wasteful process because resources have already gone into the production of faulty parts. The aim should be to capture defects before they occur.

The Jidoka tool is also applied here as a means of capturing and reporting the occurrence of a defect. Another closely related device is the andon which is also a signal to the process that an error has occurred that needs correcting.

Andon System

6. Standardize and Improve

Standard work sheets and the information contained in them are important elements of the Toyota Production System. For a production person to be able to write a standard work sheet that other workers can understand, he or she must be convinced of its importance…. High production efficiency has been maintained by preventing the recurrence of defective products, operational mistakes, and accidents, and by incorporating workers’ ideas. All of this is possible because of the inconspicuous standard work sheet».

Taiichi Ohno

A standard is the best-known way of doing work. The principle of standardization serves as a reference point for further improvement and also as a means of training new workers on how to complete tasks. Without standards, there can be no way of improving in a lean system.

Improvement on the current way of doing things is a continuous process, and once improvement happens, a new standard must result. Rules are not cast in stone and will change through constant improvement. The tool used to support this lean principle is the Kaizen event.

7. Use visual controls

Mr. Ohno was passionate about TPS. He said you must clean up everything so you can see problems. He would complain if he could not look and see and tell if there is a problem.»

Fujio Cho,
Toyota Motor Corporation, 1999-2005

The purpose of visuals in a lean thinking organization is to communicate in a clear and unambiguous manner to the people working in a process as to the state of that process. Visual control is a lean tool used to bring problems to the surface and afford the workforce an opportunity to solve them.

When problems are hidden, there is no chance of solving them, and this leads to stagnation of the lean initiative. With visual controls, deviations from the acceptable standard are visible and countermeasure to bring the system back online can quickly be taken.

Tools used for visual control include:

5S is a systematic program that helps in orderliness and removal of waste

Process control boards show the status of processes and whether or not they are within specified limits

8. Use the right technology

Society has reached the point where one can push a button and be immediately deluged with technical and managerial information. This is all very convenient, of course, but if one is not careful there is a danger of losing the ability to think. We must remember that in the end it is the individual human being who must solve the problems».

Eiji Toyoda,
Challenge and Courage, Toyota Motor Corporation, 1983

Lean thinking organizations do not install technology just because it is the in-thing at the moment. They seriously consider whether the technology will assist them to achieve the goals or whether it will be an impediment to the attainment of value for the customer.

A good example is ERP & MRP systems. While many organizations will rush to install these complex systems, lean thinking firms will first concentrate on the simple problem solving and waste removal tools they have at their disposal. If technology is deemed to be appropriate and relevant to their current issues, the lean thinking firms will surely go ahead and purchase them.

9. Leaders are grown, not bought

Until senior management gets their egos out of the way and goes to the whole team and leads them all together … senior management will continue to miss out on the brain power and extraordinary capabilities of all their employees. At Toyota, we simply place the highest value on our team members and do the best we can to listen to them and incorporate their ideas into our planning process».

Alex Warren, former Senior VP,
former Senior VP, Toyota Motor Manufacturing, Kentucky

This lean management thinking philosophy calls for the development of competent leaders from within an organization rather than always hiring from outside. When this happens, the continuity of business is guaranteed because there is a constant pool of possible leaders who are ready to take over when the time comes.

This constant mentoring of leaders who thoroughly understand the work and live the philosophy of a company is critical in sustaining lean improvements because of maintaining institutional memory.

10. Personal development of people

Respect for people and constant challenging to do better—are these contradictory? Respect for people means respect for the mind and capability. You do not expect them to waste their time. You respect the capability of the people. Americans think teamwork is about you liking me and I liking you. Mutual respect and trust means I trust and respect that you will do your job so that we are successful as a company. It does not mean we just love each other».

Sam Heltman,
Senior Vice President of Administration Toyota Motor Manufacturing, North America (one of the first five Americans hired by Toyota)

Lean continually challenges team members to do their best to solve common business problems. By empowering the workforce to take charge of solving their problems, lean companies improve their skills which ultimately has a significant impact on the business.

The Job Instruction Method perfected at Toyota is one of the essential tools for improving the skills of the workforce in a lean environment.

11. Treat partners with respect

“Toyota is more hands-on and more driven to improving their own systems and then showing how that improves you…”

Toyota is more hands-on and more driven to improving their own systems and then showing how that improves you… Toyota will do things like level their production systems to make it easier on you. Toyota picks up our product 12 times per day. They helped move presses, moved where we get the water from, trained our employees. On the commercial side they are very hands-on also—they come in and measure and work to get cost out of the system. There is more opportunity to make profit at Toyota.

“We started with Toyota when we opened a Canadian plant with one component and, as performance improved, we were rewarded, so now we have almost the entire cockpit. Relative to all lean companies we deal with, Toyota is the best.”

An automotive supplier

Treat suppliers and all other players in the extended enterprise with respect. This principle encourages cooperation and coordination within the extended enterprise which includes suppliers at all tiers. Suppliers and their suppliers are an essential part of the value chain that delivers the needs of the customer.

Lean thinking organizations work with their suppliers and help them to improve for the benefit of all the stakeholders. They understand that their success is dependent on the success of all in a win-win relationship that is defined by mutual respect and cooperation.

12. Gain a first-hand understanding of problems

«Observe the production floor without preconceptions and with a blank mind. Repeat “why” five times to every matter».

Taiichi Ohno,
(as quoted in The Toyota Way document)

This principal focuses on problem-solving that gets to the underlying causes by intimately interrogating the problem at source. The person trying to solve a problem must go to where the problem is occurring and observe the complex interactions of all the parameters before suggesting solutions.

Genchi genbutsu means “go and see” the source of a problem and find out what the exact causes are. It is a lean way of thinking that is not satisfied with second-hand reports but calls for real confirmation at the ground.

13. Build consensus before acting

«If you’ve got a project that is supposed to be fully implemented in a year, it seems to me that the typical American company will spend about three months on planning, then they’ll begin to implement. But they’ll encounter all sorts of problems after implementation, and they’ll spend the rest of the year correcting them. However, given the same year-long project, Toyota will spend nine to 10 months planning, then implement in a small way—such as with pilot production—and be fully implemented at the end of the year, with virtually no remaining problems».

Alex Warren,
former Senior Vice President, Toyota Motor Manufacturing, Kentucky

Because business decisions affect many people, lean thinking organizations use this principle of agreement–building to communicate widely before any implementation. This agreement reduces resistance to lean programs and allows management to focus on the necessary actions required to succeed.

The nemawashi consensus-building approach is the fastest way to gain acceptance of lean initiatives through prior consultations before making final decisions.

14. Become a learning organization

«We view errors as opportunities for learning. Rather than blaming individuals, the organization takes corrective actions and distributes knowledge about each experience broadly. Learning is a continuous company-wide process as superiors motivate and train subordinates; as predecessors do the same for successors; and as team members at all levels share knowledge with one another».

The Toyota Way document 2001,
Toyota Motor Corporation

                   This principle of lean management emphasizes the need for continuous evolution through constant reflection and re-adjustment based on the learning gained in the lean journey. Businesses must not stagnate in the past, but should continuously evolve to meet current and future challenges.

Reference:

https://leanfactories.com/14-lean-management-principles/

The Toyota Way (Book) by Jeffrey K .Liker

Image Source:

https://kanbanize.com/lean-management/hoshin-kanri/what-is-hoshin-kanri

https://www.latestquality.com/andon-in-manufacturing/

https://safetyculture.com/topics/one-piece-flow/

https://www.creativesafetysupply.com/articles/kanban/

Article by: Mohamed Khaleelullah K 

The core idea behind Inventory Management is straightforward always have an adequate level of stock not too much not too less. As Profitability of an organization will directly depend on rightful inventory management since inventory level whether it’s above or below partially affected the cost of manufacturing. Well the idea sounds easy methodology and implementation is a very complicated process and without the use of adequate technology this is more time-consuming activity.

Organizational competitiveness is very important these days Inventory management is one of the key aspects of this as it can diminish the competitiveness of a business organization by increasing the overall operation cost and decreasing margin values. Quality issues such as degradation and potential obsolescence are also results of poor inventory management.

Hence it is very important to have an adequate inventory balance within the organization. Key teams (PPIC, Procurement, Production, Warehousing, Logistics) related to inventory management must work in a synchronized manner to optimize the risk of stocking too much inventory which will cure inventory holding cost or stocking out of buffer level which will result in production loss as well as delay in the deadline and Organizational values.

Inventory Type in Inventory Management

As the article moves ahead, we should get families with the main type of inventories within the organization enlisted below:

1. Raw Material

The core resources required in the manufacturing of any goods are termed Raw Materials. The raw material is the primary requirement of any production system. The feedstock or unprocessed goods are a basic part of the raw materials inventory.

2. Work-in-progress goods

Partially completed or semi-finished goods are part of WIP inventories. These are the goods that are currently in process at any certain department of a manufacturing facility.

3. Finished Goods

Completed products that are in term ready for market or customer or consumer are called finished goods inventory. These inventories are ready for sale to final customers.

4. MRO inventories

Additional spare required for purpose of Maintenance, Repair, and Operations is called MRO inventories. These inventories come in handy to keep organizations running. e.g., Lubrication repair tools, and surplus operation tools.

5. Merchandise

The inventory is bought from the supplier by the seller for retail sales.

6. Transit Inventory

Inventory in the pipeline between one Transit location to another Transit location is called Transit Inventory.

This inventory is with a logistical system. Inventory transfer between supplies and manufacturing firms is an example of transit inventory.

7. Anticipation Inventory

Due to unforeseen demand during different seasons festival organizations will always remain uncertain about the supply and demand of products.

With this seller also buys and manages additional inventories with anticipation of a rise in demand for a certain type of products Hence Anticipation Inventory takes check over that firm didn’t run out of stock while demand rises.

8. Buffer Inventory

Safety Stock kept by a manufacturing firm to overcome any type of delay or quality failure so that due production can be matched on the due date without any delay is called Buffer Inventory.

9. Decoupling Inventory

In continuous running production, there might be a chance of a problem with the machine so to tackle these problems and damage on time organizations use decoupling inventories.

These inventories proved themselves as a backup system for production and didn’t let the system slow down due to damage or breakdown.

10. Cycle Inventory

The component of the total amount of inventory that is for fulfilling the regular demand is Cycle Inventory. It inhabits the material which will be utilized primarily for the fulfilment of customer demand in the standard manufacturing cycle of an organization. The finished product of these inventories has constant sales and they get replenished inside a continuous loop hence embarking the cycle inventory.

Inventory Management Tactics and Methods

Apart from the inventory management system we use, it is also essential to adopt the use of inventory management tactics and methods as it will help in the improvement of the overall inventory management system.

Not only the overall inventory management but the inventory kept in the warehouse and storage area should be properly Vigilance. To achieve proper warehouse, control few tools are suggested below

• Air-free storage
• Bend free
• Count free
• Search free
• Heavy material on the ground
• Fast consumables near the entrance
• Climb free
• Adequate lightening
• Adequate ventilation

Article by:- Sahil

What is Productivity?

Productivity is a measure of how efficiently a person completes a task. We can characterize it as the rate at which an organization or nation produces labor and products (yield), typically passed judgment on in light of the measures of resources (work, capital, energy, or different assets) used to convey that labor and products.

Why is productivity important?

Increased productivity indicates greater output from the same amount of input. It means higher efficiency with which a company or economy can transform resources into goods. Thus, productivity growth is our opportunity to create more from less.

Increased productivity drives economic growth, meaning an economy can produce and consume more and more goods and services for the same amount of work. Every section of society, viz., consumers, workers, and employers, can benefit from a productivity increase. It is vital to individuals, businesses, and analysts.

Looking at the benefits derived from increased productivity in the workplace

• Effective utilization of resources
• Production costs have been reduced.
• Reduced prices of goods and services
• Increased wages for workers
• lower overhead costs.
• Higher profits for businesses
• High per capita income
• Overall, prosperity and growth

How to improve productivity?

According to Eliyahu Goldratt, in his book “The Goal,” he states that to become more productive, you must first know your goal and measure whether an organization is leading towards the goal or being productive day by day or not, given the three measures to track it.

3 key measures given by him are Throughput, Inventory and Operational expense. Where he characterizes each of them as,

• Throughput: the rate at which the system generates money through sales net of variable costs. This corresponds to the value added by the system.
• Inventory: “all the money that system has invested in purchasing things which it intends to sell,” This was later expanded to include all investment such as plant, property, equipment etc. 
• Operating Expense: “all the money the system spends in order to turn inventory into throughput.” These fixed costs like rent and salaries are incurred whether or not throughput increases or decreases costs. This corresponds to the value added by the system.

These 3 measures jointly account for how money flows in, out, or gets stuck in a manufacturing system. The goal is to concurrently increase throughput and reduce inventory and operating expenses.

Factors influencing productivity

The factors that influence productivity can be classified broadly into two categories:

(A) Controllable Factors.

(B) Uncontrollable Factor.

(A) Controllable Factors:

Controllable Factors are considered as internal factors. These are the factors which are in control of industrial organization. They are as follows,

1 Material and Power:

Improved quality of raw materials and increased use of power have a favorable effect on productivity. An effort to reduce materials and energy consumption brings about considerable improvement in productivity.

It consist:

1. Selection of quality material and right material.
2. Control of wastage and scrap.
3. Effective stock control.
4. Development of sources of supply.
5. Optimum energy utilization and energy savings.

2. Machinery and Plant Layout

The size of the plant and the capacity utilization has direct bearing on productivity. Production below or above the optimum level will be uneconomical and will tend towards a lower level of productivity. The arrangement of machines and position in the plant and the setup of the work-bench of an individual worker will determine how economically and efficiently production will be ferried out.

3. Human Factors:

Human nature and human behavior are the most significant determinants of productivity. Human factors include both their ability as well as their willingness.

4. Ability to Work:

Ability to work is governed by education, training, experience and aptitude of the employees. Productivity of an organization depends upon the competence and caliber of its people (both workers and managers).

5. Willingness to Work:

Motivation and morale of people are very important factors that determine productivity. These are affected by wage incentive schemes, labor participation in management, communication systems, informal group relations, promotion policy, union Management relations, quality of leadership, working hours, sanitation, ventilation, subsidized canteen and company transport etc.

6. Organization and Managerial Factors:

Organization factors include various steps taken by the organization towards maintaining better industrial relations such as delegation and decentralization of authority. These factors also influence motivation likewise the existence of group, with higher productivity as their goal is likely to contribute to the organization objectives.

The competence and attitudes of managers have an important bearing on productivity. Competent and dedicated managers can obtain extraordinary results from ordinary people. Job performance of employees depends on their ability and willingness to work.

7. Technological Factors:

Technological factors exert significant influence on the level of productivity.

These include the following:

1. Size and capacity of plant
2. Product design and standardization
3. Production planning and control
4. Plant layout and location
5. Materials handling system
6. Inspection and quality control
7. Machinery and equipment used
8. Research and development

(B) Uncontrollable Factors:

Uncontrollable factors are known as external factors and these factors are beyond the control of the individual industrial organization. They are as follows

1 Economic Political and Social Changes:

There are economic, social and political factors that affect productivity.

2. Economic Factors like Size of the market, banking and credit facilities, transport and communication systems, etc. are important factors influencing productivity.
3. Political Factors like Law and order, stability of government, harmony between states etc. are essential for high productivity in industries. Taxation policies of the government influence willingness to work, capital formation, modernization and expansion of plants etc. Industrial policy affects the size, and capacity of plants. Elimination of sick and inefficient units also helps to improve productivity.
4. Social Factors like Social customs, traditions and institutions influence attitudes towards work and job. For instance, bias on the basis of caste, religion, etc., inhibited the growth of modern industry in some countries. The joint family system affected incentives to work hard in India. Close ties with land and native places hampered stability and discipline among industrial labor.

2. Natural Resources

Natural factors such as physical, geographical and climate conditions exert considerable influence on productivity, particularly in extreme climates (too cold or too hot) tends to be comparatively low. Natural resources like water, fuel and minerals influence productivity.

3. Government Factor:

According to Eliyahu Goldratt, in his book “The Goal,” he states that to become more productive, you must first know your goal and measure whether an organization is leading towards the goal or being productive day by day or not, given the three measures to track it.t.

“Every action that brings a company closer to its goal is productive. Every action that does not bring a company closer to its goal is not productive.” ~ Eliyahu Goldratt

References

https://www.simplilearn.com/what-is-productivity-and-how-to-define-and-measure-it-article

https://www.tocinstitute.org/the-goal-summary.html

https://readingraphics.com/book-summary-the-goal-a-process-of-ongoing-improvement/

https://www.economicsdiscussion.net/management/productivity-meaning-concept-formulas

Image source : https://www.tocinstitute.org/the-goal-summary.html

Article by:- Ritik Darji

1.0 Line Balancing

Line balancing or Assembly line balancing is a technique used to assign work to the workstations in such a way that  optimal continuous production flow is achieved. Line balancing indicates smooth flow of processes where there is minimum WIPs (Work-in-process) for every operation to sustain the production or assembly process. It was introduced by Henry Ford in the early 19^th century. They created an assembly line which was pulled on a continuous basis where the assemble is carried out at each stations. Initially in 1913, they took 12hrs and 8mins to assemble the chassis, but it later in 1914, it took only 93mins to assemble a new Model-T in a moving production line.

2.0 Where to use line balancing?

The Line balancing is used in case where there are multiple work stations in an assembly or production line as well as the cycle time and the production flow is to be balanced with the available takt time.

There are few factors that needs to be considered while performing line balancing.

• The individual processing time of workstations should not vary even if several operators are working parallel in the station.
• Understand the precedence of the workflow

3.0 How to perform Line balancing?

Step 1. Define the tasks

The first step is defining all the steps or tasks in the processes involved in production or assembly line.

Step 2. Identify Precedence Diagram

List the precedence and relationships of the tasks defined. A precedence diagram will represent the flow of the process using nodes and arrows for activities.

Step 3. Find out the number of workstations.

3.1 Sum of all Cycle times

The sum of cycle times of all tasks are calculated from the precedence table. All the tasks identified in the assembly are taken for calculation.

3.2. Takt time

Takt time is the rate at which units or services needs to be processed in order to meet the rate of customer demand. “Takt” is a German word for “heartbeat” or “rhythm”. So takt time is the output rhythm for the process that needs to be achieved to satisfy the customer demand.

3.3 Number of workstation calculation

Step 4. Selection and assigning tasks to the workstation

After identifying the workstations, select the workstation based on the precedence diagram and workstation tasks group.

Step 5. Understand the efficiency of the line

Based on the current cycle time of the workstation, calculate the efficiency of the line. We can further improve the efficiency on a later stage based on demand.

Step 6. Line Rebalancing

The rebalancing can be done for the improved customer demand in future. The same steps will be continued to rebalance the line for improved customer demand.

Assembly line balancing problems

Assigning tasks to workstations is one of the challenges in an assembly line. Each and every tasks will be having different type of cycle time and type of process requirements.

For having an efficient line, the line should be balanced with minimum Mura(unevenness), Muda (waste) and Muri (overburden)

4.0 An Example of Line balancing

A production line has to produce 300 units in a 9hr shift. The company is running in single shift per day with 2 tea-breaks of 15mins each in morning and afternoon and a 1hr lunch break.

The problem can be solved by using the line balancing technique.

4.1. First understand the tasks and prepared the sequence diagram along with cycle time as provided below and plot the precedence diagram.

4.2 Calculate the available time cycle time for the day.

Shift time per day = 9hrs= 9*60=540mins

Breaks = 1hr +(2*15mins) = 90mins

Available time per day = (540-90)*60= 27000secs/day

Demand per day = 300 units/day

Takt time = 27000/300= 90secs

Therefore,1unit must be produced every 90secs in the assembly line.

4.3 Calculate number of stations

Now the least number of machine in the workstations that needs to be balanced with the takt time of 90sec.

We have the total cycle time of all tasks = 270sec

=270/90 = 3stations

Thus the manager need 3 stations to produce a unit in every 90secs.

4.4 Workstation assignment

The longer operation time integer heuristic method to assign tasks to workstation. The Table 1, shows the workstations and their tasks after balancing the assembly line for a takt of 90secs.

Table 2: Cycle time of individual tasks in workstations

4.5 Identify the flow

The cycle time for individual workstations are plotted in Table 2., to get an understanding on how the cycle time is balanced with respect to target takt time.

4.6 The final assembly line

The graph shows how the assembly line is balanced with respect to the takt time. The final assembly line will be as shown in the figure 3, below.

Article  by:- Ansil Rahman

Reference

1. https://www.businessmanagementideas.com/industries/line-balancing-and-its-methods-industries/9218
2. https://theinvestorsbook.com/assembly-line-balancing.html
3. https://detroithistorical.org/learn/encyclopedia-of-detroit/model-t
4. https://www.machinemetrics.com/blog/line-balancing
5. https://www.six-sigma-material.com/Line-Balancing.html
6. https://kanbanize.com/continuous-flow/takt-time

We always look to improve order to delivery time, which is a key to any business. In order to achieve that we need to build robust processes and the network.

There are many proven principles which help to do the same, we may classify them production processes and distribution process.

Let’s have a look on design of the production process

• Layouts
  1. Group Technology
  2. Quality at the source
  3. JIT Production
• Production Schedules
  1. Uniform plant loading
  2. Kanban production control system
  3. Determination of number of Kanban needed
  4. Minimized setup times

Apart from production, Distribution plays a key role

• Supply Chain
  1. Specialized plant
  2. Collaboration with suppliers
  3. Building a supply chain

Group Technology: Group Technology is a philosophy in which similar parts are grouped into families, and the processes required to make the are arranged in a manufacturing cell. Instead of transferring jobs from one specialized department to another, group technology considers all operations required to make a part or groups those machines together. The group technology cells eliminate movement and queue (Waiting Time) between operations and reduce inventory. Since it requires operators to be more flexible to run several machines and processes, it advances operators skill levels, which will have its benefits on job security

Quality at source: Doing right the first time, and when something goes wrong, stop the process or assembly line immediately. Operators become their own inspectors, personally responsible for the quality of their output. Operators concentrate on one part of the job at a time so quality problems are uncovered. If the pace is too fast, if the operator finds a quantity problem, or if safety issue is discovered, the operator is obligated to push the button to stop the line and turn on a visual signal.

JIT: Just – In Time means producing what is needed when needed and no more. Anything over the minimum amount necessary is viewed as waste because effort and material expended for something not needed now cannot be utilized. This is contrast to relying on extra material just in case something goes wrong. JIT is typically applied to repetitive manufacturing, which is when the same or similar items are made one after another. JIT does not require large volumes and can be applied to any repetitive segment of business regardless of where the appear. Under JIT, the ideal lot size or production batch is one. Although workstations may be geographically dispersed, it is important to minimize transit time and keep transfer quantities small – typically one-tenth of a day’s production. Vendors even ship several times a day to their customers to keep lot sizes small and inventory low (If adequate source of supply is not available nearby, we may consider setting up of vendor part, It’s a topic of another discussion)

Production Schedule: We always plan but not schedule, it is a problem we need to acknowledge. Planning without proper scheduling is like fishing in a desert. We know we want to fish, but have no clue when to fish

In typical production environment the order level changes, which leads to overburden in some cases and lack of work in other cases. To mitigate this, we need to create a stable schedule over a long horizon. This is accomplished by level scheduling, freeze windows and underutilization of capacity. A level schedule is one that requires material to be pulled into final assembly in a pattern uniform enough to allow the various elements of production to respond to pull signals. It does not necessarily mean that the usage of every part on an assembly line is identified hour by hour for days on end. It means that a given production system equipped with flexible setups and a fixed amount of material in the pipelines can respond to the dynamic needs of the assembly line

The term freeze window refers to that period of time during which the schedule is fixed and no further changes are possible. And added benefit of the stable schedule is seen in how parts and components are accounted for in a pull system. Here, the concept of backflush is used where the parts that go into each unit of the product are periodically removed from the inventory and accounted for the based on the number of units produced

Uniform plant loading: Smoothing the production flow to dampen the reaction waves that normally occurs in response to schedule variations is called uniform plant loading. When change is made in final assembly, the changes are magnified throughout the line and the supply chain. The only way to eliminate the problem is to make adjustments as small as possible by setting a firm monthly production plan for which output rate is frozen

Kanban: A Kanban control system uses a signaling device to regulate JIT Flows. Kanban mean “Sign” or “instruction card” in Japanese. There are many two types of Kanban which is flowed that is production Kanban, Withdraw Kanban.

On the top of the Kanban for visual management we can use these possible approaches

• Kanban Squares: Some companies use marked spaces on the floor or the table to identify where material should be stored. When the square is empty, the supplying operations are authorized to produce, when the square is full, no parts are needed
• Container system: Sometimes containers itself can be used as signal device. In this case, an empty container on the factory floor visually signals the need to fill it. The amount of inventory is adjusted by simply adding or removing containers
• Colored golf balls: When a part used in a subassembly is down to its queue limit, the assembler rolls a colored ball down a pipe to the replenishment machine center. This tells the operator which part to make next. Many variations have been developed on this approach.

Determining number of Kanban Card Needed: Setting up a Kanban control system require determination of the number of Kanban cards needed.

We may use the below formula to determine the number of Kanban card needed

Here,

k = Number of Kanban Card

Expected demand during lead time is a product of Average Number of units demanded per period ( D) * Lead time to replenish an order (L)

Safety Stock (S) expressed as percentage of demand during the lead time

Container Size (C ) is how much the container can hold

Supply Chain: Building a supply chain involves taking a system approach to integrating the partners. Supply must be coordinated with the need of the production facilities, and production must be tied directly to the demand of the customers for products

Specialized Plant: Plant designed for one purpose can be constructed and operated more economically. These plant needs to be linked together so they can be synchronized to one another and to the actual need of the market. Speed and quick response are keys to success of supply chain

Collaboration with Suppliers: Just as customers and employees are key components of lean systems, Suppliers are also important to the process. If a firm shares its projected usage requirements with its vendors, they have long term picture of the demands that will be placed on their production and distribution system. Some vendors are linked online with a customer to share production scheduling and input needs data. This permits them to develop level production systems. Confidence in supplier or vendor’s delivery commitment allows reductions of buffer inventories. Some vendors adopt quality practices where the product need not be inspected and can be delivered directly to the line

Building a supply chain: A supply chain is the sum total of organizations involved – from raw materials firms through tiers of suppliers to original equipment manufacturers, onward to the ultimate distribution and delivery of the finished product to the customer.

We may follow the following guidelines

• Value must be defined jointly for each product family, along with the target cost based on the customer’s perception of value
• All firms along the value stream must make an adequate return on their investment related to the value stream
• The firm must work together to identify and eliminate waste
• When cost targets are met, the firms along the stream will immediately conduct new analysis to identify remaining waste and set new targets
• Every participating firm has the right to examine every activity in every firm relevant to the value stream as part of the joint search of waste

In a nutshell, to establish the successful supply chain every one needs to on the same page. Let us help you out getting on the same page. Follow gembaconcepts.com

Ref.

Richard B. Chase – Supply chain management

Article By:-

Shivam Shrivastav

Overall Equipment Effectiveness (OEE) is a term coined by Seiichi Nakajima in the 1960s to evaluate how effectively a manufacturing operation is utilized.

OEE (Overall Equipment Effectiveness) is the gold standard for measuring manufacturing productivity. Simply put – it identifies the percentage of manufacturing time that is truly productive. An OEE score of 100% means you are manufacturing only good parts, as fast as possible, with no stop time. In the language of OEE, that means 100% Quality (only good parts), 100% Performance (as fast as possible), and 100% Availability (no stop time).

Measuring OEE is a manufacturing best practice. By measuring OEE and the underlying losses, you will gain important insights on how to systematically improve your manufacturing process. OEE is the single best metric for identifying losses, benchmarking progress, and improving the productivity of manufacturing equipment (i.e., eliminating waste). OEE measurement is also commonly used as a Key Performance Indicator (KPI) in conjunction with lean manufacturing efforts to provide an indicator of success.

TEEP (Total Effective Equipment Performance) is a performance metric that provides insights as to the true capacity of your manufacturing operation. It takes into account both Equipment Losses (as measured by OEE) and Schedule Losses (as measured by Utilization).

TEEP is calculated by multiplying four factors: Availability, Performance, Quality, and Utilization.

Let’s briefly contrast OEE and TEEP:

• OEE measures the percentage of Planned Production Time that is truly productive.
• TEEP measures the percentage of all time that is truly productive.

Total Effective Equipment Performance (TEEP) measures OEE against all calendar hours, i.e., 24 hours per day, 365 days per year. TEEP, therefore, reports the ‘bottom line’ utilization of assets.

The 4 underlying metrics provide understanding as to why and where the OEE and TEEP gaps exist:

• Utilization: The portion of the TEEP metric that represents the percentage of total calendar time that is actually scheduled for operation.

• Availability: Availability takes into account Availability Loss, which includes any events that stop planned production for an appreciable length of time.

• Performance: Performance takes into account Performance Loss, which accounts for anything that causes the manufacturing process to run at less than the maximum possible speed when it is running (including both Slow Cycles and Small Stops).

• Quality: Quality takes into account Quality Loss, which accounts for manufactured parts that do not meet quality standards. The portion of the OEE metric that represents the good units produced as a percentage of the total units started.

Utilization Losses: –

TEEP (and utilization losses) indicate how much capacity is waiting to be unlocked in your ‘hidden factory’. It shows how much potential can be increased with current equipment. In many cases, reclaiming time from your hidden factory is a faster and less expensive alternative to purchasing new equipment. Utilization losses are usually grouped as plant not open or production not scheduled.

Examples of plant not open losses include:

• Breaks/meals if the production in manual in nature (continuous plants carry on running).
• Night and weekends.
• Public holidays.

Examples of production not scheduled include:

• Lack of market demand.
• Unfavourable economics, e.g., raw material prices too high.
• Lack of feedstock/storage.

Availability Losses: –

Example of unplanned availability losses include:

• Unplanned maintenance.
• General breakdowns.
• Equipment failures.
• Tooling failures.

Example of planned availability losses include:

• Planned maintenance.
• Planned operational downtime, e.g., setup, changeover, cleaning, filter/screen change.
• Warm-up time.
• Major adjustments.
• Material shortages.
• Unofficial breaks or tardiness around shift start/end and breaks.

Performance Losses: –

Example of minor stoppage performance losses include:

• Obstructed product flow.
• Component jams.
• Sensor blocked.
• Delivery blocked.
• Cleaning/checking.

Example of speed performance losses include:

• Under nameplate/design/maximum sustainable rate.
• Low product quality (that requires slower processing).
• Equipment wear.
• Operator inefficiency.
• Operator fatigue

Quality Losses: –

Example of quality losses include:

• Unsellable production such as scrap and rejects.
• Product downgrade.
• Yield losses, possibly fully, partially or not impactable.
• Process upsets/in-process damage.
• In-process expiration.
• Incorrect assembly.

Three methodologies for improving OEE in manufacturing: –

The three most popular manufacturing improvement methodologies are Lean Manufacturing, Six Sigma, and Theory of Constraints. OEE was developed as part of Lean Manufacturing – specifically as part of the powerful and holistic improvement process known as TPM (Total Productive Maintenance).

A Fourth Methodology: IDA

This introduces a simple and universal methodology for driving any improvement activity and shows you how to apply it to OEE. The methodology is known as IDA (Information, Decision, Action).

IDA (Information, Decision, Action) is a simple and highly effective process for improving productivity using information.

IDA emphasizes three factors:

• Information: Information is the foundation and starting point of IDA. Excellent information (i.e., accurate, relevant, and easy-to-understand) is a precondition for effective decision-making.
• Decision: Decisions are the pivot between Information and Action. It is the moment in time when Information is reviewed and a course of Action is decided.
• Action: Action is where theoretical possibilities are transformed into tangible progress; where Decisions are transformed into Results.

IDA is simple and universal. You may have noticed that the equation looks a lot like OEE. Three factors are multiplied together to get an answer:

Availability × Performance × Quality = OEE

Information × Decision × Action = Result

References

www.oee.com

Article By

Tanmay