Lean Manufacturing Technique for Textile and Garments Industry | Removal of Wastes Through LeanPosted by Firoz Kabir on Monday, June 16, 20141

Lean ManufacturingLean manufacturing is a systematic approach to identifying and eliminating wastes through continuous improvement by conveying

the product at the pull of the customer in pursuit of production.

Lean Manufacturing is a systematic approach for achieving the shortest possible cycle time by eliminating the process waste

through continuous improvement. Thus making the operation very efficient and only consisting of value adding steps from start to

finish. In simple words lean is manufacturing without waste.

Below are the few steps which are required to implement lean manufacturing

   Identifying the fact that there are wastes to be removed.

   Analyzing the wastes and finding the root causes for these wastes.

   Finding the solution for these root causes.

   Application of these solutions and achieving the objective.

 History of Lean:

Lean vs Traditional Manufacturing Process:For years manufacturers have created products in anticipation of having a market for them. Operations have traditionally been

driven by sales forecasts and firms tended to stockpile inventories in case they were needed. A key difference in Lean

Manufacturing is that it is based on the concept that production can and should be driven by real customer demand.A lean

organization can make twice as much product with twice the quality and half the time and space, at half the cost, with a fraction of

the normal work-in-process inventory. Lean management is about operating the most efficient and effective organization possible,

with least cost and zero waste

 THE LEAN PRODUCTION GOALS:The principal goal of lean manufacturing is to create a continuous flow of Product from raw material to finished goods and on to the

customer – no stoppages, no delays, no Interruptions because of inventory scrap or yield issues, downtime or the other problems

that occur in a typical manufacturing operation.

Maximizing value (give the customer what they exactly need)

Minimizing waste (eliminate anything not needed for delivering value)

Pursuing perfection

Reduce Time

Reduce Total Costs

Cost Reduction by Elimination of Waste

It requires constant effort at cost reduction to maintain continuous profits in manufacturing. The prime way to reduce costs is to

produce only those products determined by sales in a timely fashion, to restrain excessive manufacturing and to eliminate all waste

in manufacturing methods. There are various ways to analyze and implement cost reduction, from the start of designing all the way

through to manufacturing and sales. One of the goals of Lean Manufacturing is to locate waste pragmatically in each process and

then eliminate it. It is possible to uncover a very large amount of waste by observing employees, equipment, materials and

organization in the actual production line from the perspectives of the process itself and the actual work involved. Some types of

waste are obvious, but others are hidden. Waste never improves value; it only increases cost. The thorough elimination of waste

leads to greater employee self-respect and to major cost reductions by preventing unneeded losses.

Creating Conditions to Guarantee Product Quality

To produce a high-quality product is the first commandment of any manufacturing company. The high quality of any product, in

which many component and parts do not fail and are trouble free, must be built into it at every process. Lean Manufacturing has

developed various ways to support the commitment to “build the quality into the process.” This principle gives each operator the

responsibility to check quality thoroughly at every stage of work within the process, and brings product inspection directly into the

process so that good products flow to the following process and defects are extracted at that point. Each operator must be aware

that “the following process is a customer” and must never send a defective product to downstream processes. If equipment is

defective or operates abnormally, either the machine itself or some system must be able to detect the problem and stop operation.

Foolproof devices are often used as simple means for this purpose. This also makes it easier to maintain quality. Lean

Manufacturing has taken many measures and expended much effort to see that, if a defect in quality should occur, we can uncover

the true cause and apply countermeasures to prevent its recurrence.

Creating a Work Site with Operators in Mind

If labor is expended on a product but does not contribute any additional value to it, that labor is of no value. On the other hand, if the

labor expended on a product enhances the product’s value, then that labor is of great value because it is effective. This type of

effective labor use translates into showing respect for human dignity, the dignity of the employee. In the Lean Manufacturing

measures have been taken so that the labor or every employee will

enhance the value of our products. One of these measures is Standardized Work. This is a way to perform the most effective

sequential production without waste by rationally concentrating the work around the Operators’ movement. Some companies use a

system that stresses the performance of equipment and machines. In this case, the equipment is considered to be of prime

importance and the employee mere expansion of the machine. Mutual support is indispensable if each employee, who plays the

leading role for his particular task, is to perform the work and improve the efficiency of the whole production process. In Lean

Manufacturing the implementation of mutual support between the preceding and succeeding processes has affected highly efficient

work. If the Operator discovers some problem in the work for which he is responsible, he or she is permitted to stop the line

depending on the gravity of the problem. This is only possible against

a backdrop of respect for the judgment and intelligence of the employees. A work site, where every employee can fully display his

own ability, can be created with a system in which the work accomplishments of each individual are a matter of public knowledge,

and anyone can propose kaizen for work problems.

Awareness of WasteCost Reduction versus Cost Plus

Lean Manufacturing improves productivity through the principle of Cost Reduction.

With the principle of cost reduction, the sales price of a product is determined by actual market

conditions. A profit cannot be secured, thus, without first reducing cost regardless of increases

or decreases in the production quantity. This type of cost philosophy requires an overall

company effort. Cost reduction is:

Profit = Sales price – Cost

In contrast to cost reduction, there is the cost-plus principle, in which product price is

determined by combining all the costs -- such as those of raw materials, labor and other

expenses needed for production -- with whatever company policy decides is needed as profit.

Cost policy:

Sales price = Cost + Profit

The two formulas above are the same mathematically, but there is a great difference in the

emphasis each one places on the variables. In other words, cost-plus considers that the cost is

fixed. While cost reduction considers, that the cost can be effectively changed by

manufacturing methods.

Main Kinds of WastesSeven main types of wastes were identified as a part of the Toyota Production System. However, this list has been modified and

expanded by various practitioners of lean manufacturing and generally includes the following:

Overproduction

It is unnecessary to produce more than the customer demands, or producing it too early before it is needed. This increases the risk

of obsolescence and the risk of producing the wrong thing. It tends to lead to excessive lead and storage times. In addition, it leads

to excessive work-in-process stocks which result in the physical dislocation of operations with consequent poorer communication

Defects

In addition to physical defects which directly add to the costs of goods sold, this may include errors in paperwork, late delivery,

production according to incorrect specifications, use of too much raw materials or generation of unnecessary scrap. When defect

occurs, rework may be required; otherwise the product will be scrapped. Generation of defects will not only waste material and labor

resources, but it will also create material shortages, hinder meeting schedules, create idle time at subsequent workstations and

extend the manufacturing lead time.

Inventory

It means having unnecessarily high levels of raw materials, works-in-process and finished products. Extra inventory leads to higher

inventory financing costs, higher storage costs and higher defect rates. It tends to increase lead time, prevents rapid identification of

problems and increase space requirements. In order to conduct effective purchasing, it is especially necessary to eliminate

inventory due to incorrect lead times.

Transportation

It includes any movement of materials that does not add any value to the product, such as moving materials between workstations.

Transportation between processing stages results in prolonging production cycle times, the inefficient use of labor and space. Any

movement in the

firms could be viewed as waste. Double handling and excessive movements are likely to cause damage and deterioration with the

distance of communication between 

processes.

Waiting

It is idle time for workers or machines due to bottlenecks or inefficient production flow on the factory floor. It includes small delays

between processing of units.When time is being used ineffectively, then the waste of waiting occurs. This waste occurs whenever

goods are not moving or being worked on. This waste affects both goods and workers, each spending time waiting. Waiting time for

workers may be used for training or maintenance activities and should not result in overproduction

MotionIt includes any unnecessary physical motions or walking by workers which divert them from actual processing work. This might

include walking around the factory floor to look for a tool, or even unnecessary or difficult physical movements, due to poorly

designed ergonomics, which slow down the workers. It involves poor ergonomics of production, where operators have to stretch,

bend and pick up when such actions could be avoided.

Over-processing

It is unintentionally doing more processing work than the customer requires in terms of product quality or features such as polishing

or applying finishing in some areas of product that will not be seen by the customer . Over-processing occurs in situations where

overly complex

solutions are found to simple procedures. The over-complexity discourages ownership and encourages employees to overproduce

to recover the large investment in the complex machines.

The Eighth Waste – Skills

Sometimes in focusing on the elimination of the seven wastes, companies forget about the aspect of Lean that is inherent in the

philosophy as it was originally developed in Japan – respect for people. In other words, the recognition that a company’s most

important assets are its employees. To that end, Lean practitioners sometimes add an eighth waste to the list – skills. This waste

occurs when company does not fully leverage the gifts and talents of its associates. In fact, employees may even decide to leave a

company for the simple reason that they do not feel as though they are being listened to or valued, and, as such, they feel like a

number in a sea of numbers.

THE BASIC LEAN MANUFACTURING PRINCIPLES:

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

achieve:

1.      Value

Specify value from the standpoint of the end customer by product family.

2.       Value stream mapping 

Identify all the steps in the value stream for each product family, eliminating whenever possible those steps that do not create value.

3.       Flow 

Make the value-creating steps occur in tight sequence so the product will flow smoothly toward the customer.

4.       Pull 

As flow is introduced, let customers pull value from the next upstream activity.

5.       Perfection 

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 TOOLS & TECHNIQUES:Here are some of the most important tools of lean, ones that a typical lean practitioner must be

proficient it and capable of applying:

• Value Stream Mapping

• Takt Time

• EPEI

• Leveling (Heijunka)

• Pull Systems

• Setup Reduction

• Pokayoke (Mistake Proofing)

• 5S

• Seven QC Tools

• JIT

• Kanban

Value Stream Mapping

Value stream mapping is the identification of all the specific activities (material and information

flow) as well as the resulting lead times occurring along the value stream for a particular product or

product family, usually represented pictorially in a value stream map.

Takt Time

Takt time is the rate at which product must be turned out to satisfy market demand. It is determined

by dividing the available production time by the rate of customer demand. It is a calculated number,

not a reflection of your capability. It sets the pace of production to match the rate of customer

demand.

EPEI

A measure of how frequently a process can produce all the items assigned to it. For example, if a machine is able to change over

and produce the required quantity of all the high-running part types dedicated to it within three days, then the production batch size

for each individual part type is about three days worth of parts. Thus this machine is making every part every three days.

Leveling (Heijunka)

Leveling is the sequencing of orders in a repetitive pattern, and the smoothing of day-to-day

variations in total orders to correspond to longer-term demand.

Pull Systems

A pull system is a system of production and delivery instructions in which nothing is produced by

the upstream supplier until the downstream customer signals a need. Pull can operate with single

units or small batches. It enables production without preset schedules.

checklists, worksheets, diagrams, area maps, etc., and may pertain to equipment use, operations,

processes, metrics, storage, safety, quality, movement in an area, or general use of the environment.

Setup Reduction (Single Minute Exchange of Dies or SMED)

SMED is a series of operator techniques pioneered by Shigeo Shingo that result in changeovers of

production machinery in less than ten minutes. The long-term objective is always zero setup, in

which changeovers are instantaneous and do not interfere in any way with one-piece flow.

Poka-yoke (Mistake Proofing)

Japanese term used by Shigeo Shingo to mean "innocent mistake-proofing," it is an improvement

technology that uses a device or procedure to prevent defects or equipment malfunction during

order-taking or manufacture. Mistake proofing devices are important to the production line in

several ways: 

(1) enforce correct operations by eliminating choices that lead to incorrect actions,

(2) signal or stop a process if an error is made or a defect created

(3) prevent machine and product damage.

5SFive S (5S) an improvement process, originally summarized by five Japanese words beginning

with S, to create a workplace that will meet the criteria of visual control and lean production. Seiri

(sort) means to separate needed tools, parts, and instructions from the unneeded and to remove

the latter. Seiton (set in order) means to neatly arrange and identify parts and tools for ease of use.

Seiso (shine) means to clean and inspect. Seiketsu (standardize) means to require as the norm that

everyone sort, set in order, and shine at frequent (daily) intervals to keep the workplace in perfect

condition, and also to make use of visual control systems. Shitsuke (sustain) means to maintain the

five S gains by training and encouraging workers to form the habit of always following the first

four Ss. 

SEVEN QC TOOLS:

 Check sheet or tally sheet

 Histogram

 Pareto chart

 Cause and effect diagram

 Process flow chart

 Control chart

 Scatter diagram

JIT (JUST IN TIME):

Just in time (JIT) is a production strategy that strives to improve a business return on investment by reducing in-process inventory

and associated carrying costs. To meet JIT objectives, the process relies on signals or Kanban between different points in the

process, which tell production when to make the next part. Kanban are usually 'tickets' but can be simple visual signals, such as the

presence or absence of a part on a shelf. Implemented correctly, JIT focuses on continuous improvement and can improve a

manufacturing organization's return on investment, quality, and efficiency. To achieve continuous improvement key areas of focus

could be flow, employee involvement and quality.

KANBAN TOOLING:

Kanban is one of most popular tools in lean manufacturing. This is a simple concept, but very effective. Kanban mainly focus on the

reduction of overproduction. There are mainly two types of kanbans. They are

 Withdrawal kanban

 Production kanban

BENEFITS OF LEAN MANUFACTURINGThe implementation of lean manufacturing through trying to make value flow at the pull of the customer (Just In Time) prevents and

eliminates waste in your processes. Waste being categorized as part of the seven wastes: Transport, Inventory, Motion, Waiting,

Over-processing, Overproduction, and Defects.

Many studies have shown that we only add value for around 5% of the time within our operations, the remaining 95% is waste!

Imagine if you could remove that 95% wasted time and effort; what would it do for your operations?

Typically Lean will improve;

Quality performance, fewer defects and rework (in house and at customer).

Fewer Machine and Process Breakdowns.

Lower levels of Inventory.

Greater levels of Stock Turnover.

Less Space Required.

Higher efficiencies, more output per man hour.

Improved delivery performance.

Faster Development.

Greater Customer Satisfaction.

Improved employee morale and involvement.

Improved Supplier Relations.

HIGHER PROFITS!

INCREASED BUSINESS