Mistake Proofing (Poka-yoke)-How it save upto one million dollar in industry

Good Morning Friends,

Today's our topic is Mistake proofing/Poka-Yoke.

Generally the most effective way to achieve quality is to avoid having defects in the first place. It is much less costly to prevent a problem from ever happening than it is to find and correct the problem after it has occurred. In this article we can learn What is Poka Yoke, How it helps save the million of money, When to use it, how to use it, benefits of Poka yoke etc.

What is Mistake proofing/Poka yoke?

Poka-Yoke is a Japanese term that means “mistake-proofing”. It is the use of any automatic device or method that either makes it impossible for an error to occur or makes the error immediately obvious once it has occurred.  In other words, the goal is to make an object that prevents the user from messing up. Small design features and visual clues can influence the safety and efficiency of everyday objects.

The main aim of mistake proofing is:

Prevent a defect from occurring and when this is not possible, Detect the defect every time  occurs.

When to use mistake proofing?

Poka-yoke can be used wherever something can go wrong or an error can be made. It is a technique, a tool that can be applied to any type of process be it in manufacturing or the service industry. Errors are many types -

Processing error: Process operation missed or not performed per the standard operating procedure. 

Setup error: Using the wrong tooling or setting machine adjustments incorrectly.                     Missing part: Not all parts included in the assembly, welding, or other processes.
Improper part/item: Wrong part used in the process.  

Operations error: Carrying out an operation incorrectly; having the incorrect version of the specification.

Measurement error: Errors in machine adjustment, test measurement or dimensions of a part coming in from a supplier.

How to use mistake proofing?

Step by step process in applying Poka-yoke:

1. Obtain or create a process flow chart also Pareto chart of the error. Review each step, thinking about where and when human errors are likely to occur.
2. For each potential error, work back through the process to find its source.
3. For each error, think of potential ways to make it impossible for the error to occur. Consider:  Elimination—eliminating the step that causes the error,Replacement—replacing the step with an error-proof one,Facilitation—making the correct action far easier than the error.
4. If you cannot make it impossible for the error to occur, think of ways to detect the error and minimize its effects. Consider Inspection method , setting function and regulatory function.
5. Choose the best mistake-proofing method or device for each error. Test it, then implement it. Three kinds of inspection methods provide rapid feedback:

• Self-inspection means workers check their own work immediately after doing it.
• Successive inspection is done at the next step of the process by the next worker.
• Source inspection checks, before the process step takes place, that conditions are correct. Often it’s automatic and keeps the process from proceeding until conditions are right.

Practical Example of Poka yoke:

1. Sensors

Proximity sensors emit a high-frequency magnetic field and detect an upset in the field when an object enters it. They can be used to detect the presence or absence of an object.

Applications

• Sensing of tank or bin level
• Confirmation of part or object passes by
• Detection presence or absence of object
• Positioning of work piece

2. Error Detection & Alarms

In general, an error detection device can provide a visual alarm such as a flashing light or an audible alarm such as a horn or siren.These devices signal that a problem is either about to occur or has just happened. With a warning effect, the response is not automatic; someone has to take action.

Applications

• The signal must be triggered by something in the process, usually a sensor.

3 Some bad and good Poka Yoke

Here we can consider example of credit card

bad Poka yoke- credit card slot requires card to be slid in only one (of four possible) directions
better Poka yoke -credit card slot accepts card either direction, but only on correct side
even better Poka yoke - credit card slot accepts card slid no matter how you do it
poke-yoke = chip in credit card, just get it anywhere near card reader


Ideally, poka-yoke ensures that proper conditions exist before actually executing a process step, preventing defects from occurring in the first place. Where this is not possible, poka-yoke performs a detective function, eliminating defects in the process as early as possible. Don't allow defects to occur in your processes by neglecting to prevent mistakes in your work. Use poka-yoke to make the work easier and mistake proof your process


Thanks friend for reading, I welcome for any comments or feedback about post.
also please reply for any details information.
Thank You.

How to do process mapping -Value stream mapping

Good  Morning Friends,

Today's Our topic is Value stream mapping.

Here some people are confuse about value stream mapping (VSM) and plant layout. in layout we are mentioning only plant or machinery layout, flow from inside the plant but in VSM we are taking care of parts and information flow. its not only related to equipment flow  but also information & parts from customer to supplier end. we can see in details how it works & helpful to industry.

Below we will go through

What is VSM

VSM Symbols

Defining the process boundaries

The Process Steps

Information Flows

Process Data

Calculating the Time Line

Multiple Suppliers and Customers

Interpreting the Data

Next Steps (Ideal and future state maps)

What is value stream mapping?

Value stream mapping is a lean-management method for analyzing the current state and designing a future state for the series of events that take a product or service from its beginning through to the customer. At Toyota, it is known as "material and information flow mapping".

This enables you to see at a glance where the delays are in your process, any restraints and excessive inventory. Your current state map is the first step in working towards your ideal state for your organization.

Value Stream Analysis-

Planning tool to optimize the result of eliminating waste.

Select the product/family

identify the current state VSM which describe the process as it today

Apply lean technique to reduce the waste.

Create future state of VSM which describe the ideal state based on lean principles

Purpose of VSM & Why its required in Lean?

1) Provide optimum value to the customer through a complete value creation process with minimum waste in:

– Design (Concept to customer)

– Build (order to delivery)

– Sustain (in-use through life cycle to service)

2) Many organizations pursuing “lean” conversions have realized that improvement events alone are not enough

3) Improvement events create localized improvements, value stream mapping & analysis

strengthens the gains by providing vision and plans that connect all improvement activities

4) Value stream mapping & analysis is a tool that allows you to see waste, and plan to eliminate it

VSM Symbol-

The picture to the below shows some of the commonly used value stream mapping symbols and their meanings. It is not necessary to use these specific symbols, if you have symbols that are more relevant / descriptive for your processes then use those.

Guideline to create VSM-

1) Select the product or product family

Firstly we need to decide what it is exactly that we wish to map, in a company with many products there may have to be some initial work done to identify which product or family group of products that should be mapped, we may decide to go with highest volume or value, or take a longer term strategic look at those product ranges that we expect to do more business with in the future or we may be guided by our customers as to what to map.

2)Bound the Process

We need to decide the limits of our map, most value stream maps are conducted from supplier through to customer within an organization and these should be the first boxes placed on your VSM to bound the process. It is possible to map the entire supply chain, in this case the start and end points for your process map would be the raw materials and the final consumer.

3)Process Steps

process flow start from customer to supplier or supplier end. The process steps are the various operations that are performed on the product, these are generally located in a single place with one point that inventory enters and then leaves. We are not breaking down each operation into specific tasks, there are other process mapping techniques such as flow charting that would be a better tool for analyzing to that level of detail.

4)Add Information flow-

One of the things that differentiates a VSM from most other mapping tools is the inclusion of the information flows into the map. We need to include how the customers order product, frequency and method, and how we translate that back to our supplier. We also include how we then communicate requirements to our processes to ensure that we produce what the customer wants.

5) Collect and add data

This where we need to do a little thinking and some work, get the team to collect data regarding the performance of each step of the process; typical types of date to collect are;

• Inventory
• Cycle time (time taken to make one product)
• Change over time (from last good piece to next)
• Up-time (on-demand machine utilization)
• Shifts worked
• Net available working time
• Scrap rate
• Pack size/pallet sizes
• Batch Size

6)Time line & Inventory

We create the time line to give us information about total process times and lead times for inventory through our processes; we use the inventory at each stage and the daily demand to calculate the amount of stock in days and add this to the top of the time line, this will allow us to calculate a total lead time. The cycle time for one product is then placed in the lower portion and this will be added to give a total processing time.
It is usual to at this point to have lead times that are several days to several weeks and processing times that are only a few minutes which highlights just how much waste there is in our system.

7) Multiple Suppliers and Customers in VSM

The map produced above is a fairly simple map with just one customer and one supplier, more often than not we have multiple suppliers and customers and it may be necessary to draw on more than one. In this case the process is still the same but when you calculate your timeline use the worst case for inventory. If you have many suppliers it may be worth concentrating on your most important suppliers or grouping them into similar types such as fasteners.
More often than not you can still show multiple customers as one, or if required as groups with similar requirements such as weekly or monthly demands.

Step by step procedure with case study (Practical example) :

I would like to give live example of my Ex company Tata yazaki. It producing wiring harness, here at production we face some problems as follows.

-Shortage in the supply of harness to the Tata customer

-High level of inventory and safety stock of almost 10 days

-Quality complains are increasing day by day so big problem to Maintain the PPM.

Problem are going to increased day by day so start a Gambia meeting in factory. Action done as follows, guideline help to Improve the VSM.

1) Select your Team

We select the team   that each area or stakeholder of the process is represented e.g. Sales, Purchasing, Warehouse etc.


2) Select process to be mapped

Value Stream Mapping is suitable for most businesses and can be used in Manufacturing, Logistics, Supply Chain and some Service orientated Organizations so we select map based on that.

3)Collect data and produce current map

We collected data of process times, inventory or materials information, customer (or demand)requirement the future state maps will be developed using information captured here so it’s imperative

4) Critic current stage

we have big problem in our process flow also Layout so change that accordingly also done brainstorming process to get the idea.

-Challenge the current thinking, encourage your team to make suggestions, look for areas of waste.

5)Map future state

-Compile the future state map on the base of current state of map and the critiques

6) Create action plan and deploy it

Taking a future state map consider an action plan that could be implemented to change the current process to the future state

7)Measure the benefits

as per problem check, we got benefits in inventory, also less material handling, no shortage in demand of supply to the customer also customer satisfaction level increased and our factory rating change from B+ to A .

Key Tips  for VSM:

• Experience directly. You (or your team) should follow the whole value stream yourself. Don’t rely on impressions, assumptions, or conversations about how things “usually” happen. If it’s a physical thing, walk it, use a stopwatch to time various steps, and experience it all as directly as possible. At least one team member needs to walk the whole stream. If you rely on subteams to walk different portions, and nobody walks the whole thing, you will miss an essential perspective to VSM.
• Sketch an initial VSM by hand. Start by sketching in pencil as you document the steps. Later you can use chart-drawing software to communicate and collaborate better and map out a future/ideal state.
• Do initial walk-through. You might start with a quick walk to experience it at an overview level, and then do it again in more detail.
• Try doing it in reverse, from end product or service to its origins. Various items could become more clear and meaningful with that perspective. Many veteran VSM practitioners do it this way.
• Keep asking why. In Lean Six Sigma, it’s sometimes called the Five Whys. The idea is to simply ask why something is done as it is. To the response, another why is asked. This continues until you drill down to the ultimate basis for the action.

 If you have any doubt or query about value stream mapping creating or overview please reply me.

Thanks

Lean manufacturing principle-step by step principle

Good Morning Friends,

 Lean manufacturing principles-Implementation

There are several key lean manufacturing principles that need to be understood in order to implement lean. Failure to understand and apply these principles will most likely result in failure or a lack of commitment from everyone in your organization. Without commitment the process becomes ineffective. This page reviews some of the more critical lean manufacturing principles and should help you get started. Consider these to be the "guiding principles" of lean manufacturing as there are others that have not been included.

The five-step thought process for guiding the implementation of lean techniques is easy to remember, but not always easy to achieve:

1. Specify value from the standpoint of the end customer by product family.
2. Identify all the steps in the value stream for each product family, eliminating whenever possible those steps that do not create value.
3. Make the value-creating steps occur in tight sequence so the product will flow smoothly toward the customer.
4. As flow is introduced, let customers pull value from the next upstream activity.
5. As value is specified, value streams are identified, wasted steps are removed, and flow and pull are introduced, begin the process again and continue it until a state of perfection is reached in which perfect value is created with no waste.

 Lean Manufacturing Principles-

Elimination of Waste

One of the most critical principles of lean manufacturing is the elimination of waste (known as muda in the Toyota Production System).

The Seven Wastes of Lean Manufacturing are;

• Transport
• Inventory
• Motion
• Waiting
• Over-Processing
• Overproduction
• Defects

Although the above mentioned types of waste were originally geared toward manufacturing, they can be applied to many different types of business. The idea of waste elimination is to review all areas in your organization, determine where the non-value added work is and reduce or eliminate it.

Kaizen (Continuous Improvement)

Kaizen is the strategy where employees work together proactively to achieve regular, incremental improvements in the manufacturing process.

It should truly form the basis of your lean implementation. Without continuous improvement your progress will cease. As the name implies, Continuous Improvement promotes constant, necessary change toward achievement of a desired state. The changes can be big or small but must lend itself toward improvement (often many small changes are required to achieve the target). The process truly is continual as there is always room for improvement.

Continuous Improvement should be a mind-set throughout your whole organization. Do not get caught up in only trying to find the big ideas. Small ideas will often times lead to big improvements.

Respect For Humanity

The next lean manufacturing principle has to do with people. The most valuable resource to any company are the people who work for it. Without these people the business does not succeed. When people do not feel respected, they tend to lose respect for the company. This can become a major problem when you are trying to implement lean.
Most people want to perform well in their jobs. Not only do they go to work to earn a living, but they also want to develop a sense of worth in their work. They want to feel like they have contributed to the company goals, like their work and effort has meant something.
Some of the methods to ensure your people know you respect them is through constant communication, praise of a job well done, listening to their ideas and helping out when necessary.

Heijunka (Levelized Production)

Heijunka is a form of production scheduling that purposely manufactures in much smaller batches by sequencing (mixing) product variants within the same process
As mentioned on the home page, the foundation of lean manufacturing is levelized production. The basis of this principle is that the work load is the same (or level) every day. Most manufacturing companies are at the mercy of their customers for orders. Before producing product, they wait to get orders. This leads to increased delivery lead time which may not satisfy customer requirements.

On the other end of the spectrum, some companies will produce based strictly on a forecast. This may result in excess product that is not required by the customer. it takes into consideration both forecast and history. The key ingredient for this lean manufacturing principle is utilization of a pull system.

 

Just in time

Pull parts through production based on customer demand instead of pushing parts through production based on projected demand. Relies on many lean tools, such as continuous flow, Heijunka, Kanban, Standardize work and Takt time   Working in conjuction with levelized production, this principle works well with kanbans (a pull system). It allows for movement and production of parts only when required. This means components are not used in product that is not required and no time is wasted building unsaleable product.

Just in time helps to maintain inventory level, also due to just in time concept material & money will not stuck, money flow will be fast. also product  quality will increased so customer satisfaction level will increased.

Quality Built In

The last key lean manufacturing principle that I would like to touch on is Quality in built. The idea behind this principle is that quality is built into the manufacturing process. Quality is built into the design of the part. Quality is built into the packaging. Throughout all areas of the product, from design to shipping, quality is a major consideration.
Automation with a human touch falls within this principle. Machines that can detect defects and stop production are an excellent example of this principle. Part profile mistake-proofing, which prevents an operator from mis-orienting parts, is another excellent example. In Lean Manufacturing (or any other system), the focus must be on doing it right the first time.

 

There are some more principle also involve, you get from basic lean manufacturing concept blog. I am happy after looking the there is someone interested to learn the lean manufacturing. this will not direct helpful to implement the lean manufacturing but helpful to understand the fundamental of the lean.

Thanks friends for reading, in the next blog we can see how to implement the lean manufacturing concept in factory.

Thanks and have a nice day!

Inventory Management: Manage Inventories to Manage Cash Flow

Today's topic is Inventory management

First we can understand what is inventory and types of inventory.
What is Inventory &Its Type
- Stock of items kept to meet future demand
- Purpose of inventory management

• What to order
• How many units to order
• When to order

Reasons to hold the inventory-

• Meet variation in Production Demand
• Cater to Cyclical and Seasonal Demand
• Economies of Scale in Procurement
• Take advantage of Price Increase and Quantity Discounts
• Reduce Transit Cost and Transit Times
• Long Lead and High demand items need to be held in Inventory
• 
  

Reasons not to hold the inventory-

• Risk of inventory becoming obsolete
• Risk of item not selling
• Higher storage/space costs
• Risk of natural disasters
• Higher insurance premiums

So how can you keep the perfect inventory balance?

While it is true that there are different ways to get around many of the cons on the list, it is important to keep in mind these very real issues that present themselves when dealing with keeping excess inventory on hand.
In many cases, you will probably find that keeping additional inventory in stock is a good thing. You have probably found that having enough of a hot-selling product is a constant problem. Rather than come up short when a customer is eager to buy, it is wise to keep a few more in the back, in reserve so that your shelves are never empty (which doesn’t look good for any retailer).
One way to help ensure that you always have a good balance of inventory is to use software specifically designed to manage item based businesses. For example, in Flow Inventory will alert you when your stock hits a certain point and allows you to create a purchase order with a few clicks.

Techniques of Inventory Control

There are a number of different techniques employed by wholesale distributors to ensure their inventory control is maximizing efficiency and profitability. Below are six key techniques of inventory control for wholesalers and distributors of durable goods:

1) Establishing Annual Stocking Policies

Management must decide the maximum and minimum level of stocks and supplies that need to be kept in the warehouse or across the network of warehouse locations. Management must also set optimized re-order levels, safety stock levels (below which supply must not be allowed to fall) and an average inventory level to ensure costs are contained.

2) Preparation of Inventory Budgets

Many organizations have an annual inventory budget and they are usually prepared well in advance before inventory is procured. Budgets should include the total cost of ownership to keep inventory on hand during that year’s account period. This includes materials cost, fixed operational costs, carrying costs, logistics costs, redistribution costs and additional miscellaneous costs that contribute to the total costs of ownership.

3) Maintaining A Perpetual Inventory System

Also known as “the automatic inventory system”, this method is designed to keep a constant track of the quantity and value of each stocked item. Many wholesale distributors leverage a combination of an Enterprises resource planning in conjunction with an Inventory Optimization solution, such as easy Stock, to optimize inventory balances. Most ERP and WMS technologies struggle to keep costs low and service rates high, which is why optimization software can be so valuable to operations processes

4) ABC Analysis and ABC Classification

The fastest moving products in your inventory should be located closest to the shipping, staging, and receiving area in the lower-right of the diagram below. As the demand for each product decreases over time, products should be migrated backwards to free up space for items with higher inventory turnover  or for new product introductions that have high demand. Since the majority of your picking activity is performed in a rather small area, your warehouse layout should be optimized to reduce time spent looking for product in the back of the warehouse.

5) Kanban

The word Kanban means card;
It is a card(oradocument) that representsan Order of material from one Customer to one Supplier;
The basic information printed on the Kanban is:

• Material identification(and code).
• Customer identification.
• Supplier identification.
• Quantity to be supplied.

Order to Kanban:
2 types of orders can be transformed in Kanban:

• Customer orders
• Replenishment orders

Kanban help to meet the Pull system. also help to maintain the inventory.

Case Study-

In Tata yazaki big problem was high inventory also safety stock for 10 days so space shortage was problem.

Action-
management has decided to implement Kanban system from raw material store to Finish goods products.

difficulty-Starting very much problem in implementation, just like missing card missing, change management not involve in kanban so wrong wire length cutting, people not ready to change easily

Step by step guide

• Again brain storming meeting from management
• define problem phase
• Current condition
• Solution-Implement kanban
• targets & Goal
• demonstration in one line
• Implement to one line
• Again modify the project
• finally successfully got the result

Advantages-

38% Inventory reduction in yazaki  plant store

safety stock Inventory reduce from 15 days to 2 days

20 % Space save at shop floor

Thanks for reading, give your comments if you need more information or query.

Lean Mnufacturing-What it can do for your company?

Good morning all, I am  Rupesh Deshmukh (Mechanical Engineer)

Today's our topic is the basics of Lean manufacturing.

First why lean manufacturing required to earn profit. Now a days very high competition during modern age of technology. to fulfill the need of Customer very good Quality, lowest Cost, on time delivery. All industries are facing the challenge of reduce cost by improving quality.
All these requirements are fulfill by Lean manufacturing  and industry can earn more profit.




What is mean by Lean?


Lean manufacturing or lean production, often simply "lean", is a systematic method for the elimination of waste within a manufacturing system.
Elimination of Muda-Waste
                        Muri- Overburden
                        Mura-Unevenness
Working from the perspective of the client who consumes a product or service, value added work.

                                                Model of Lean production system




Types of waste-

Transport -(moving products that are not actually required to perform the processing)

Inventory -(all components, work in progress and finished product not being processed)

Motion -(people or equipment moving or walking more than is required to perform the processing)

Waiting (waiting for the next production step, interruptions of production during shift change)

Overproduction (production ahead of demand)

Over Processing (resulting from poor tool or product design creating activity)

Defects (the effort involved in inspecting for and fixing defects)^[

Steps to achieve lean systems

The following steps should be implemented to create the ideal lean manufacturing system:^[37]

• Design a simple manufacturing system
• Recognize that there is always room for improvement
• Continuously improve the lean manufacturing system design

Lean Manufacturing tools:

5S :Organize the work area

• Sort (eliminate that which is not needed)
• Set In Order (organize remaining items)
• Shine (clean and inspect work area)
• Standardize (write standards for above)
• Sustain (regularly apply the standards)

Eliminates waste that results from a poorly organized work area (e.g. wasting time looking for a tool).

Andon::

Visual feedback system for the plant floor that indicates production status, alerts when assistance is needed, and empowers operators to stop the production process.

Acts as a real-time communication tool for the plant floor that brings immediate attention to problems as they occur – so they can be instantly addressed.

Bottleneck Analysis :

Identify which part of the manufacturing process limits the overall throughput and improve the performance of that part of the process.

Improves throughput by strengthening the weakest link in the manufacturing process.

Continuous/single piece Flow:

Manufacturing where work-in-process smoothly flows through production with minimal (or no) buffers between steps of the manufacturing process.

Eliminates many forms of waste (e.g. inventory, waiting time, and transport).

TPM Equipment reliability:

Total productive maintenance is the best tool which help for maintenance of equipment  that  aims  at achieving  an  optimal  production environment  devoid  of  defects,  downtime,  stoppages and accidents.

Kanban:

Kanban means card information. Kanban is an inventory control system to control the supply chain.

Types of kanban systems-

Production (P) Kanban:

Transportation (T) Kanban

SMED: Single minute exchange of die

 It provides a rapid and efficient way of converting a manufacturing process from running the current product to running the next product. This rapid changeover is key to reducing production lot sizes and thereby improving flow.

The phrase "single minute" does not mean that all changeovers and startups should take only one minute, but that they should take less than 10 minutes (in other words, "single-digit minute").

FMEA-Failure Mode Effects Analysis

it is a step-by-step approach for identifying all possible failures in a design, a manufacturing or  assembly process, or a product or service.

“Failure modes” means the ways, or modes, in which something might fail

“Effects analysis” refers to studying the consequences of those failures

Value stream mapping

 It is a lean-management method for analyzing the current state and designing a future state for the series of events that take a product or service from its beginning through to the customer. At Toyota, it is known as "material and information flow mapping".

Poka yoke

It is a Japanese term that means "mistake-proofing" or “inadvertent error prevention”. A poka-yoke device is one that prevents incorrect parts from being made or assembled, or easily identifies a flaw or error.

Kaizen

Kaizen, means  "improvement." When used in the business sense and applied to the workplace, kaizen refers to activities that continuously improve all functions and involve all employees from the top management to operator. It is nothing but change for better.

Advantages of Lean Manufacturing

• Improved quality 

• Improved Visual Management

• Increased efficiency

• Manpower reductions

• Easier to manage

• Total Company Involvement

• Problem Elimination

• Reduced Space

• Safer Work Environment

• Improved employee morale

Thank you All for reading.in the next blog we can go in details with live industry example.