Ch. 8 Lean Systems
Seiri/Sort
5-c campaign= clear out intent= red tag suspected unnecessary items. after a monitoring period, throw them out
Transportation root causes
Mislocated materials Unlevel scheduling Unfavorable facility layout Poor organization/ housekeeping Unbalanced processes
Motions root causes
Poor ergonomics and layout Machine and process design Nonstandardized work methods Poor organization
Waiting root causes
Unbalanced workload Unplanned maintenance Long process set up times Misuse of automation Unlevel scheduling Ineffective layout Too much specialization.
simplification/ standardization
an emphasis on eliminating non value process steps and on executing process steps in exactly the same way each time
poka yoke
an emphasis on redesiging processes in such way to make mistakes either impossible or immedietley apparent to the worker ex: before giving medicines or blood, a nurse checks bar codes on the item and on the patients bracelet to ensure the patient is receiving the right treatment
objectives and principles of lean systems
produce: 1. only the products customers want 2. as quickly as they want them 3. with features they want 4. with perfect quality 5. in the minimum possible lead times 6. with no waste of labor, materials, or equipment 7. using methods that reinforce the occupational development of workers
why are employees viewed as critical resources for success
-acceptance: everyone must buy into the goals and approaches underlying lean -source of flexibility: at the heart of lean is the emphasis on building the flexibility to respond directly to customer demands. this demands on employees who are multiskilled and cross trained -working in teams -power in their hands: employee empowerment;
benefits of lean systems
-in stable environments: -reduce lead times -improve quality -reduce sot -improve customer service -strive to eliminate need for inventory, lead time, and capacity buffers
shared value and beliefs
-manage the data: data analysis replaces opinions -waste is a symptom: rather they are seen as results of problems elsewhere -goals are to be met: its management's role to find out how to help everyone meet their goals -standardization is fundamental to performance improvement: standardization highlights variation and abnormalities. it simplifies problem solving -process orientation: attaining superior behavior by identifying critical processes and changing them
seiton/straighten
5-c campaign= configure put everything in an orderly fashion so that it can be located frequently done by footprinting
Inventory symptoms
Complex tracking systems Extra storage and handling Extra rework/ hidden problems Paperwork and documents Stagnated information flow High disposal costs In process packaging
Processing symptoms
Extra equipment Longer lead time Reduced productivity Extra Material movement Sorting, testing, inspection Inappropriate use of resources Excess energy consumption Processing by products
Transportation symptoms
Extra handling equipment Large storage areas Over staffing Damaged product Extra paper work and hand offs Excessive energy consumption
Symptoms of over production
Extra inventory Excess floor space utilized Unbalance material flow Complex info management Disposal charges Extra waste handling and treatment High utility costs
Inventory root causes
Just in case logic Incapable processes Unbalanced workload Unreliable supplier shipments Inadequate measurement and reward system
Product defect root causes
Lack of process control and error prodding Deficient planned maintenance Poor product design Customer needs not understood Improper handling Inadequate training
Processing root causes
Product changes without process changes Just in case logic Lack of communication Redundant approvals and inspections Undefined customer requirements Stop gap measures that become routine Lack of reuse/ recycling
Overproduction root causes
Product complexity Misuse of automation Long process set ups Unlevel scheduling Overengineered equipment/ capability Lack of reuse and recycling Poor market forecast
Motion symptoms
Reduced productivity Large reach and walk distances Excess handling Reduced quality People and machines waiting
Product defects symptoms
Rework, repair, and scrap Customer returns Loss of customer confidence Missed shipments and deliveries Hazardous waste generation High disposal cost
Symptoms of waiting
Underutilization of resources Reduced productivity Increase in investment Idle equipment Large waiting and storage rooms Equipment running, not producing Unnecessary testing
load leveling
a calculation of the average rate of production needed for each item based on the overall TAKT time
Jidoka
a focus on developing tech. features of equipment and processes that automatically detect and flag problems ex: a limit switch on a machine might monitor contents of a feeding bin and light a signal or sound when the bin becomes nearly empty
process analysis/ value stream mapping
a graphical technique that helps managers understand material and information flows as a product makes its way through the process also considers factors such as capacity, quality, and variability generates two maps the first is the current state map which describes the current vlue stream and the second is the future map which is the revised process designed to increase the % value metric by identifying and eliminating any non value adding steps in the process
tools and techniques that implement lean systems: TAKT time flow balancing
a lean systems scheduling approach aimed at synchronizing the output rate of customer demand.
lean systems approach
a philosophy that emphasizes the minimization of the amount of all resources used in the various activities of the enterprise. the defining objective is to eliminate waste
tools and techniques that implement lean systems: Kanban (Pull) Scheduling
a scheduling system that builds output in response to actual customer demand two basic types- production kanbans and withdrawal kanbans in a push system, movements are controlled by a schedule based on forecasted demand and fixed operating times
kaizen events
a short term cross functional project aimed at improving an existing process
push scheduling
a system where activities are initiated and products are moved according to a schedule, irrespective of whether or not the customer demands it
lean
a systematic approach that has been developed to help managers identify and reduce/eliminate waste and variance in the processes under their control
5-s program
a systematic program for effective housekeeping in operational processes
pull system
activities in operating processes are initiated by actual customer demands, not by schedules based on forecasts. in doing so, only whats produced is what customers want, when they want it, and where
stop and fix (line stop) systems
an operator should stop the process and immedietely fix the problems, rather than allowing it to continue to make poor quality output
production kanbans
authorizes a worker to replenish an empty bin, specifying the type of parts and the number to build when an empty bin arrives at a workstation with a production kanban attached, its a signal to build a new batch of of items to fill the bin
withdrawal kanbans
authorizes someone to withdraw a standard amount of specific parts from a container. if a worker processing the job runs out of a part, the ______ that accompanied the job gives that person the authority to take an empty bin to a replenishment area to exchange for a full bin
strategic benefit of lean systems
can lower BE point of production quantity (minimum amount needed to sell to earn profit) by increasing CM (difference of price and firms direct cost) and decrease fixed OH costs by eliminating waste the lean approach lowers variable production costs associated with labor, materials, and energy, thus raising the unit profitability of products. CM may also go up if the firm can charge higher prices Lean also attacks waste associated with fixed costs of facilities, equipment, capital, etc improvements in the use of resources that affect fixed and variable costs drive the production BE point downward, enhancing the firm's flexibility the firm can afford to produce smaller quantities, allowing niche marketing, and can change outputs more quickly in response to changes in customer demand
seiso/scrub
clean and check clean out everything and eliminate the sources of dirt
7 wastes in product design
complexity precision variability sensitivity immaturity danger high skill
seiketsu/ sytemize
conform make cleaning and checking routine. set the standard, train and maintain
shitsuke/ standardize
custom and practice standardize the previous four steps into one process and continue to improve it.
mixed model scheduling
decide how to distribute the production of different products over time
first three objectives
emphasize producing exactly what customers want JIT, building at the same rate of demand if managers can synchronize production with demand, they can eliminate many sorts of waste
objectives 4-6
emphasize the quality, timeliness, an cost elements associated with creating value for customers
tools and techniques that implement lean systems: total productive maintenance TPM
equipment failure, set ups, process speed loss, and quality defects can often all be traced to a lack of preventive maintenance. this works to identify and prevent all potential causes of breakdowns to achieve and ambitious goal of zero unplanned downtime emphasize shop floor organization, disciplined adherence to operating procedures, rigorous equipment design and upkeep, and a focus on preventing problems rather than fixing them
shared cultural beliefs- principle 2
identify a value stream for each product firm must clearly understand and link together all the activities involved in product development, order processing, production, and delivery this analysis identifies different types of muda waste is a symptom of problems elsewhere. to reduce waste, workers must quantify the impact, uncover underlying root causes, and attack them
tools and techniques that implement lean systems: group tech - cellular manufacturing
in contrast to a functional layout or a product layout, this gathers in one location all of the equipment and work skills necessary for complete production of a family of similar products.
shared cultural beliefs- principle 4
let the customer pull value from the producer source of a pull system
shared cultural beliefs- principle 3
make value flow without interruptions means that the movements of materials and information in value streams should be swift and even the key indicator that this state is attained is very little inventory. excess amounts often removes the needed urgency to identify and address problems created by root causes
visual control
making current performance and potential problems immedietely visually apparent reduces waste by reducing reaction time and by maintaining a sense of urgency can be done with mobile technology
gemba kaizen
managers and employees are obligated to see the problems and issues in person rather than relying on reports
kanban and MRP
mrp tells the system what to produce and when the items are needed kanbans determine the exact order and know with which production is to be carried out
risks of lean systems
opertational/ tech: forecast errors, capacity constraints, IT disruptions social: labor strikes, sabotage natural/hazard: fire, flood, monsoon, etc economy/competition: interest rate, bankruptcy of supply partners legal: lawsuits, wars, border customers, regulations
quality at the source
practice of eliminating defects at their root cause origination points reducing the potential for quality problems downstream three techniques often used: jidoka, stop and fix systems, and andons
shared cultural beliefs- principle 1
precisely specify value for each specific product consumer determines value engage in dialogue to determine whats valuable
shared cultural beliefs- principle 5
pursue perfection suggests that continual improvement is always possible
employee empowerment
putting the responsibility for attacking waste with the employees directly involved in the processes
tools and techniques that implement lean systems: focused factories
reduces customer- induced variance by grouping together similar customers and then designing and implementing production systems to serve these specific customers. underlying logic- a factory focused on a few specific tasks will outperform a factory attempting to serve many different demands. a factory can be product or market focused
last objective
reflects lean's greater emphasis on employees as the primary agents for improving operations employees closest to the causes of waste should be problem solvers
SMED
stage 1- separate internal and external setups internal: any setup procedure occurring while equipment sits idle external: any setup activity that workers complete while the equipment operates stage 2- covert internal to external stage 3-streamline all activities in a setup this stage tries to get rid of any activity performed to make adjustments, calibrations, elaborate positioning, unnecessary tightening, or trial runs
lean design
the application of lean principles and tools to the task of designing products 3 major goals: design products that meet customer needs design products that support corporate obj and that meaningfully differentiate the firm and its products design products that reduce/minimize waste
lean system culture
the culture present in lean systems and that places a high value on respect for people in the system employees must be empowered
level, mixed model scheduling
the practice of leveling quantities of different models produced over a period of time with the goal of reducing batch sizes and lead times appotions batches of each product to be produced evenly throughout the day the number of occurrences of each product is proportionate to the level of demand promotes the lean systems goal of simple flows through simple methods. offers a ay to achieve swift, even response to market demand
set up reduction
the processes used to reduce setup and changeover times wth the goal of making output smaller and batches more efficient usually involves process mapping and analysis to identify steps that can be eliminated, executed faster, or done in parallel.
stat process control
the use of various tools for analyzing the capabilities of a given process and for monitoring its performance with the goal of flagging potential problems before they occur
andons (trouble lights)
the use of visual indicator systems such as flashing lights to help management assess current performance and quickly identify the location of current problems
