10.2 Lean Production

Lean production may be summarised by the application of the following principles

Flexibility Visual control aids Market pull processing Managing production flow Waste reduction or minimisation Constantly seeking improvement Strong long term relationships with suppliers Error minimisation and perfect first time quality

Overproduction

Occurs when operations continues awe demand has been met. It can be also occur when products are made earlier than necessary, resulting in excess inventory that requires storage

Unnecessary or excess motion

Refers to movement of employees and tooling due to inefficient workspace design. Motion is another process that adds no value to the product. Within the lean system 'work' is productive movement while motion is defined as moving without working

The 5Ss

Sort, set in order (stabilise), shine, standardise, sustain the practise. 5s is a lean tool used in conjunction with other lean manufacturing approaches to organise and then maximise the efficiency of the workplace. Originally developed in Japan

Sustain

Sustaining concerns itself with the discipline of maintaining systems that address the roots causes of inefficiencies through well trained staff and the use of visual aids. It refers to the commitment required to initiate and maintain the first four of the 5s.

Lean Prodution cost

Cost reduction is achieved through the elimination of wage and costly errors. Strong links with suppliers guarantee the integrity of supply and maintain confidence to keep inventories as close to zero as possible. The workforce is empowered to associate with the company's quality goals and foster an environment of striving for constant improvement.

Disadvantages of lean production

Disruptions in supply chains can have signify the effects on production and ultimately, products supply concerns for customers Lean manufacturing requires a whole new way of thinking foe employees and managers Physical plant and equipment setups often require reworking at significant initial investment cost Lean techniques may be overused, greater returns are evident at the earlier stages of introducing the process and future gains are harder won

Value assisting activity or operation

Does not not add value to the component, however, these operations are integral to the manufacturing process and cannot be omitted. Preventive maintanance, inspection, statistical process control etc. And so on are value assisting operations

Lean production disadvantage

Due to the nature of pressure for constant improvement lean manufacturing may suffer from slow staff morale and additional gains may also be won but at costs that are uneconomical and unsustainable

Typical principles preparing a workforce for effective use of lean strategies To be successful, use in over the following.

Employees should communicate decency and respect in all of their interactions Management implement an instruction program educating the workforce in the skills required to work together effectively Work areas are maintained in a safe, clean and orderly fashion Commutation informs all employees of business goals,molars and achievements Principles of fairness and equity to all are visible The dual principles of honesty and integrity are applied to every aspect of the workplace

Kaizen

Lean production is based in the principle of kaizen or continual incremental improvement. Through kaizen, workers employs analytical techniques, such as value steam mapping and a technique called 'the 5 whys', to quickly identify opportunities to eliminate waste and improve productivity. Kaizen may result in new ways or performing operations, procedures, duties, or involve resequencing of tasks. Kaizen is employed by all workers at every level of the organisation working together towards a common goal- consonant improvement

Role of th workforce

Lean manufacturing leverages the commitment of every employee to drive its agenda of constant improvement. Devolution of power in a fair, respectful and equitable and environment empowers every employee to be an agent of change. A highly trained and skilled workforce is better equipped to identify small, systematic and incremental improvements that accumulate to provide benefits in business practise and greater efficiency in meeting company objectives and goals.

Lean production emphasis

Lean manufacturing's emphas on reducing or elimanating waste and delivering quality products clearly has benefits for the environment. Waste in the view of lean manufacturing extends well beyond the workshop floor and even encompasses administrative operations Reduced excess or unessary material and by products

Advantages of lean production

Lean production naturally bring about efficiency and cost reductions Space saving due to lack of inventory or excess finished product Quality of product is constantly under improvement Better customer satisfaction as product is delivered on time and to the specifications required Competitive advantage over other manufacturers

Set in order

A simple mantra sums up this step: a place for everything and everything in its place. Strategic placement of these tools and holders improve efficiency and workflow. Visual cues through labelling also allows for easy identification of tools and their purpose

Principles of lean Prodution

Are applied to the entire production process, that is, from supply chains through to manufacturing. It is achieved through well designed quality control systems, with production volume and customisation based directly on market demand.

Defects

Are defined as products or services that do not meet customer specifications. Defects detected within the manufacturing phase require reworking or scrapping and are thus wasteful. If th These products or services should travel into the market place they generate customer dissatisfaction and create inefficiencies of their own

Non value adding operations

Are those activities that will not be missed if they are removed from the process. These activities are often categorised as waste. Delays, superfluous material movement, holding inventory or storage are all seen as non value adding operations

Inappropriate operations

Include extra processing, reprocessing to repair duals or handling related damage, and excess inventory generated by over production

Characteristics of lean production

Include extremely limited inventories, highly skilled workers, constant improvement in pursuit of perfection including no tolerance for defects, high levels of product diversity and customisation in an environment seeking cost reductions

Inventory is stock that is not currently required to meet immediate customer demand

Inventory may take the form of raw materials, partly processed product and finished product. Inventory is problematic because it requires additional movement and storage

Product family

Is a grouping of products and their variants that all pass through similar processing steps and common equipment just prior to shipment to the customer. This part of the production is known as the downstream end. Product families often used as the unit for analysis through value stream maps

Value stream mapping

Is also known as end to end system mapping. It is a simple but powerful tool that provides a visual aid to map the relationships between materials, processes, information and time.

Lead time

Is the average time it takes for one product unit to pass through the entire process, from start to finish , including any time waiting between sub processes. Mathematically lead time may he expressed as: Lead time=sum of all process times + sum of all delay or queue times between processes. Reduction of lead time is an important part of lean manufacturing

Transportation

Is the unnecessary motion or movement of materials, including raw materials work in progress (undergoing transportation between processing operations)

Purpose of value stream mapping

Is to identify processes that do not provide value. Processes that do not provide value are designated as waste. Value stream maps may be used to optimise individual processes, whole of factory production or even a age supply chains between multiple organisations. What if scenarios may be simulated to model future production alternatives. In the end, value stream mapping is used to identify areas of production that may be able to be streamlined or improved. This proc so is an integral part of lean manufacturing's philopshy of continuous improvement

Waiting, queueing or delays consume th precious commodity of time

This wasteful practise refers to time told where no value is being added to the product. Queueing or waiting adds to product cycle or lead times. Downstream resources not in use due to delays, waiting or queuing add to inefficiencies

The 7 wastes

Overproduction, transporting, waiting, inappropriate processing, unnecessary inventory, unnecessary/excess motion, defect. Specifically identify a series of wasteful activities found in manufacturing. The 7 wastes principles are deliberately designed to be generic to all manufacturing. The core of the philosophy is that waste occurs in a variety of forms and should be reduced and if possible removed from their manufacturing cycle. Within lean manufacturing there are strategies that exist to deal with each of the wastes, thereby improving overall efficiency, performance and quality.

Workflow analysis

Supports value steaming and classifies all take in a process. Tasks are categorised as value adding, value assisting or mom value adding

Value adding activity or operation

Transforms a component and is an indispensable part of the overall process. These operations are the processes for which a customer is willing to pay. Operations that are not categorised as value adding should be simplified, streamlined, Reduced, integrated into other activities or removed

Product family matrix

The easiest way to simplify and represent reality once the product families are established is to create a product family matrix. A product family matrix simply consists of a grid with the vertical axis listing produce and the horizontal axis displaying manufacturing process steps working backwards form the customer towards the supply of raw materials, that is, from downstream to upstream. Operations are then plotted in the appropriate grid squares, allowing for ease of identification of common product/operation groupings or families.

Standardise

This approach identifies efficient or normal operations and provides best practises on how to deal with abnormal or inefficient conditions in the workplace. These instructions or standards must be clear, easy to understand and easily communicated to workers. Once again, visual cues may be used by employing colour coding as an effective and efficient means of communication

Sort

This phrase concerns itself with the removal of unnecessary items from the workplace. This also involves use of space, and simplification of operations. Items and processes that are redundant to production or even office operations should be removed leaving only that which is determined as necessary

Shine

This refers to the cleanliness of the workplace, tooling, equipment and materials. It is the responsibility of employees at level to maintain the cleanliness of the workplace