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Evolution of lean
Lean process principles were discovered at Toyota, Japan to take on the stiff competition from the large size automobile companies from the world especially USA. Toyota was able to provide more value to customers with lesser resources and
thus increasing its market share e.g. they were able to supply vehicle models and colour of customer’s choice within stipulated time frame. The complete model of this type of manufacturing system was termed as the Toyota Production System which was based on the ‘Lean principles’. Ohno Taiichi from Toyota, Japan is known to be the father of the Toyota Production System.
The key focus of Lean is to identify and eliminate waste in the processes, here waste means activity or actions that do not add value to customers in the manufacturing process. Since Lean deals with manufacturing systems from a process point of view, it has been found that the principles of Lean can be readily implemented in other types of processes also, such as services like insurance, IT, medical/ health process and product development process. Therefore, Lean operation principles can be used to greatly improve the efficiency and speed of all sorts of business processes.
Lean deals with balancing multiple value streams i.e. a family of products or services and integrating the work done in operations and in the rest of the organization (be it a production unit, a nursing centre, a software development company, an insurance co. etc.) with a focus on customer satisfaction. The concept is very clear; "Lean" navigates any business process towards almost 100% value added with negligible waste steps or interruptions to the workflow. It encompasses both products as well as services e.g. manufacturing of cars, assembly of medical equipment etc. (as products) or orders, request for information, quotes, etc (as services).
Lean always emphasizes on:
★ Fast responses to customer issues
★ Product and Service offerings in sync with customer demands
★ Reduce cycle times
★ Elimination of waste in all its forms (7 types of waste).
Lean strongly believes in continuously eliminating waste from across all processes within the organization, this is in line with Six Sigma management systems. Also, the Lean approach challenges everything and accepts nothing as unchangeable. There is a complete cultural change observed in doing things once Lean impregnates down the system. Leader of the organization identifies an area best suited for a pilot run for Lean implementation, and slowly spreads it over the whole company. Best results are found when Lean is driven from top to bottom within the organization and becomes a part of the performance index.
Lean in the Office management
Lean in a production plant advocates for single-piece flow, in a process it tends to focus on eliminating wait time. The idea of eliminating wait time and defining single-piece flow also applies to the office and administrative areas of the company. Most overhead departments and activities do not have effective metrics. Standard work does not exist for most tasks. Most overhead departments would score poorly in a 5S assessment.
Many office (administrative/ finance or other transaction type) processes are responsible to handle the most complex transactions. The problems aroused here may cause an excessive amount of rework, delays in processing, resulting in customer dissatisfaction e.g.:
❖ Just think about the HR recruitment process. The cycle time (time elapsed from raising a manpower request to providing the same to respective dept.) will depend on various factors like Job description, Short listing, First round of interview, Second round of interview, Salary finalization, HR formalities etc. Majority of the cycle time consists of ‘Wait time’. Smart organizations have reduced this wait time from months to few days. They have also incorporated changes to avoid rework during the whole process. This is not different from what happens inside the factory. Many of these issues may be resolved by using Kaizen and 5S.
Versatile Lean tools for every need
Kaizen
Kaizen is Japanese word made by combining two words ‘Kai’ (means ‘change the thing’) and ‘Zen’ (means ‘for betterment’) i.e. make changes in the product, processes, systems, workplace etc. (wherever possible) in the organization for a good cause. Generally, these are small improvements where almost all the employees of the organization participate to make it large. Kaizen projects are easily identifiable improvement areas which may be accomplished by small teams of the size 2-3 people with a ‘just do it’ type approach. Because the solutions or fixes are normally known and the team may or may not be cross-functional depending on the nature of the task. The objective behind doing kaizen is to bring a culture within the organization where every employee contributes for enhancing customer satisfaction and eliminating waste from the system.
5 S for workplace arrangement
5S system shows us the path for creating and maintaining an organized, clean, and high performance workplace. There are 5 words starting with S, and every S depicts one of the steps of the 5S system.
5S is the foundation for continuous improvement, defect reduction, cost reduction, and a safe work area. It’s a systematic way to improve the workplace, our processes and our products through production line employee involvement. 5S is used in Six Sigma for quick wins as well as control. 5S should be one of the Lean tools that should be implemented first. If a process is in total disarray, it does not make sense to work on improvements. The process needs to be first organized (stabilized) and then improved.
5 S brief description:
➢ Sort – Clearly distinguish between items ‘needed’ from the items ‘not needed’ and eliminate the latter.
➢ Set in Order – Place the needed items in the right location to allow for easy and immediate retrieval.
➢ Shine – Keep the workplace clean.
➢ Standardize – Develop standardized working methods to maintain the first 3 steps.
➢ Sustain – Put processes in systems like checklist, periodic audit etc. to ensure that the first four steps are well practiced.
Jidoka (Autonomation)
Jidoka, also known as automation with human intelligence, is a principle that creates control of defects inside a business process. Instead of identifying defects at the end of the production line and attempting to trace errors back to a source, Jidoka demands that a process stops as soon as errors are detected so improvements or troubleshooting can happen immediately. For example, a document printer stops immediately after detecting an error and waits for human intervention. At this point of time human intelligence is required to resolve the issue.
For Jidoka to work properly, machines are often equipped to recognize bad outputs from good outputs; the machines are also equipped with a notification of some type to spark human interaction in the process when things go awry.
Just-in-Time Manufacturing
Just-in-Time manufacturing, or JIT, is another Lean concept that originated with Toyota. Originally, JIT took a literal meaning. The goal of JIT manufacturing was to produce an output “just in time,” or “as needed” by the customer. The customer was the person or process that required the output; sometimes, that meant the end customers, and, other times, the customer was a different employee or process within the organization.
In a JIT processing situation, one machine might produce a part required by another machine. JIT manufacturing means that the first machine supplies only the amount of parts that the second machine can process. If the second machine can process one part per minute, the first machine is set to produce one part per minute. You’ll recognize this idea from the sections on muda of inventory and overproduction.
It’s obviously not always possible to run a process just-in-time for the end customer, but most modern companies do try to come as close as possible. Using predictive analytics, companies attempt to estimate how many of each product will sell before they produce those products. In some cases, such as with book publishing, companies run a smaller number of items first. If those items sell well or sell out, the company orders bigger and bigger runs of the product.
Kanban
Kanban is a system that schedules lean manufacturing. It controls the supply chain to realize cost savings through implementing the just-in-time inventory control system.
“All we are doing is looking at the timeline, from the moment the customer gives us an order to the point when we collect the cash. And we are reducing the timeline by reducing the non-value adding wastes.” Taiichi Ohno
The term “Kanban” is a Japanese word that means “billboard,” and it was first coined and applied by industrial engineer Taiichi Ohno in order to improve efficiency at Toyota. Ohno looked at the way that consumers buy goods and the way that supermarkets supply them to develop a more efficient inventory system.
When you go shopping, you don’t stock up with enough supplies for months or years. You buy what you need now, and the supermarket only stocks what it expects to sell now. This doesn’t worry you because you know the supermarket will have what you need next time you shop.
In manufacturing, each process is dependent, either on a preceding process or on materials obtained from a supplier. It’s a bit like shopping at a supermarket. It wouldn’t make sense to take more than you need right now, and when you have taken it, the preceding process or metaphorical “supermarket,” knows that it must stock up again for your next visit.
“Getting the balance right,” means monitoring actual processes and results. How quickly is the production funding responding? We do want to limit stock, but we also don’t want to lose sales. If that’s happening, more Kanban has to go into the system. In other words, inventories must be built up.
Taiichi Ohno soon saw that very strict rules must be applied to the Kanban System to be effective. He stipulated that:
● Each process indicates a Kanban that will be matched by the following processes.
● Kanban indicates both sequence and quantity.
● Without a Kanban, there is no reason to produce or transport any items.
● When goods pass from one process to the next, they must have a Kanban.
● No goods may be passed on if there are any defects to speak of. Thus, Kanban also becomes a quality control system.
● The fewer Kanban there are, the more efficient and demand-sensitive any process will be.
Standard Work
‘Standard Work’ or ‘SOP’ (Standard Operation Procedure) is an important Lean tool. It’s a written work instruction where the sequence of job elements has been efficiently communicated and is repeatedly followed by a team member. It is an important prerequisite for successful implementation of Kaizen and many other aspects of Six sigma.
Standard work should be:
★ A written work instruction with all steps of the process and should have important images wherever possible.
★ Must be done by the persons responsible for the work
★ Periodic audit the process to verify if this is being followed.
Every step in the process should be defined adequately and should be done repeatedly in a similar way. If there are any variations in the process, it would most likely increase cycle time and cause rework/ defects. Some of the good aspects of adopting standardized work are as below:
➔ Get similar output every time
➔ Reduces defects/ rework
➔ Better performance
➔ Employee morale boosting
➔ Employee safety enhancement
➔ A tool for employee training
➔ Visual management- Line in-charge/ managers may verify whether the process is running as desired or not.
Poka-Yoke (or Mistake- Proofing)
Poka-yoke is the most sought tool used by every type of industry. People use it knowingly or unknowingly but it touches our daily life whether we are using a banking transaction through an ATM machine or driving our cars.
It’s a structured methodology for mistake-proofing certain key operations during a process. It is any device or mechanism that either prevents a mistake from being made or ensures that the mistakes don’t get translated into errors/ defects that the customers observe. A Poka-Yoke may be of either preventive type or detection type.
Visual Standards (Visual factory)
★ Visual Control
A visual control is any communication method used in the workplace which guides the user about the actions or activities desired to perform certain task.
These are normally the information related to the flow of work activities such as equipment, safety warnings, actions and methods etc.
Standardization may be adopted so that all standards may be identified by visual controls.
Some examples are Andon boards in assembly shop, Information boards on highways, Traffic signals etc.
★ Visual Communication
These are signs used to pass information e.g. “No smoking zone,” “Don’t honk,” “Don’t use mobile phones,” “Wear safety shoes” etc.
Value stream mapping
Value stream mapping is a lean management tool that helps visualize the steps needed to take from product creation to delivering it to the end-customer. This is a business process mapping method which helps in introspection (understanding your business better), as well as analysis and process improvement.
As we’ve already mentioned, a value stream map allows you to see a top-down overview of your business processes. Then, you can analyze the process or workflow, identifying wastes and inefficiencies. Typically, here are few things you’d want to look for:
➢ Delays that hold up the process
➢ Restraints that limit the process
➢ Excess inventory that ties up resources unproductively
While value stream mapping is usually used for manufacturing processes, the same principles can apply to other industries too.
First up, you need to decide what you want to map. In some businesses, one value stream map can cover just about everything the company does. This is especially true if your company produces a single product.
If you have a complex mix of products or services, however, then you’d have to draw a separate map for each. With which process you’d start is, of course, up to you. Generally, though, you’d want to start off with the highest value areas.
TPM
TPM alias Total productive maintenance is a complete system for maintenance of equipment that aims at achieving an optimal production environment devoid of defects, downtime, stoppages and accidents.
In fact, in a lean production setup that is practicing TPM, you find it difficult to distinguish between normal operators and maintenance staff.
This is because they all are proactively involved in the maintenance of machines which leads to increased productivity, lower costs, improved quality and extended machine lifespan.
5 S is considered as the foundation of the lean TPM program because without it the initiative won’t last long under the weight of disorganization, indiscipline and inefficiency. So, before going for the TPM program the organization must have implemented a 5 S system in the workplace.
TPM Pillars
Once a high degree of stability is established using the 5S program, an organization can start implementing the total productive maintenance in earnest. Total productive maintenance has eight pillars that are aimed at proactively establishing reliability of machines. One point that has to be made here is that people are the centre of this system and must be continuously trained to identify and eliminate waste. There are total 8 pillars of TPM as below:
❖ Jishu Hozen (Autonomous maintenance)
❖ Planned maintenance
❖ Quality maintenance
❖ Focused improvement (Kobetsu Kaizen)
❖ Early equipment maintenance
❖ Education and training
❖ Health, Safety and Environment
❖ Office TPM
Benefits of TPM implementation
❖ No Breakdowns
❖ No Small Stops or Slow Running
❖ No Defects, rework
❖ No Accidents
❖ Reduced inventory
❖ Reduced cycle time
❖ Increased productivity
❖ Enhancement in customer satisfaction
7 Waste in Lean
The seven wastes of Lean Manufacturing are what we are aiming to remove from our processes (also known as Muda).
The Seven Wastes of Lean Manufacturing are;
WORM-PIT;
1. Waiting
2. Overproduction
3. Rejects
4. Motion
5. Processing (Over Processing)
6. Inventory
7. Transport
Pull System
Pull system may be defined as making things as per demand. Traditional systems are based on Push i.e. make items even if not needed by your customer. This causes excess inventory, rework, scrap. However, in a Pull system, we pull work only when needed and that too in the right Quantities. Push systems can be summarized as ‘‘Make a huge stock of things as cheaply as possible and hope customers will take it.’’ On the other hand Pull systems can be summarized as ‘‘Don’t make things if it’s not needed, and make them fast when required.’’
Pull system demands a robust process which can handle overloading and show flexibility. A pull system is in true sense a pull system because it makes things strictly on the demand from the customer or the market, not from forecasts or previous performance. Though most businesses strive to use a pull business model from customer to shop floor, this doesn’t happen at every process of the organization, because there is a likelihood of some weak links in the supply chain which may demand a push system.
Single Minute Exchange of Dies (SMED)
SMED was developed by Shigeo Shingo, a Japanese industrial engineer who was extraordinarily successful in helping companies dramatically reduce their changeover times. His pioneering work led to documented reductions in changeover times averaging 94% (e.g. from 90 minutes to less than 5 minutes) across a wide range of companies.
SMED (Single-Minute Exchange of Dies) is a system for dramatically reducing the time it takes to complete equipment changeovers. The essence of the SMED system is to convert as many changeover steps as possible to “external” (performed while the equipment is running), and to simplify and streamline the remaining steps. The name Single-Minute Exchange of Dies comes from the goal of reducing changeover times to the “single” digits (i.e. less than 10 minutes).
A successful SMED program will have the following benefits:
● Lower manufacturing cost (faster changeovers mean less equipment downtime)
● Smaller lot sizes (faster changeovers enable more frequent product changes)
● Improved responsiveness to customer demand (smaller lot sizes enable more flexible scheduling)
● Lower inventory levels (smaller lot sizes result in lower inventory levels)
● Smoother startups (standardized changeover processes improve consistency and quality)
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