Waste Elimination Techniques

• SIMPLFY, COMBINE, ELIMINATE– First we need to “Learn to See” the waste.– We want to do our work easier, faster,

cheaper, better and safer.– A basic approach for doing this is to

– Simplify– Combine – Eliminate

Standardize Work/Standard WIP

• Standardized Work:• The best practice method of performing a

process to meet your takt time requirements in the most efficient way focusing on value-adding activities.

• Standardized WIP: • A predetermined maximum amount of work-in-

process allowed between process.• In the ideal world it’s one piece!

One-Piece Flow

• One-Piece Flow:– The condition in which each work piece

passes through the production process by itself.

– Also known as flow production

• Key things to address are:• Flow of the process • And the waste that stops the flow

Overview of Manufacturing Cells

Definition: Work Cells• Self-contained units including several

value-adding operations• Equipment and personnel arranged in

process sequence• Perform operations necessary to

complete a product or a major production sequence

Principles of Cell Layout• Sequential arrangement• Counterclockwise flow• Machines close together (caution!)• Last operation close to first

• U or C shape

• Similar products/processes in a cell to avoid radical change in setup

• Basic elements of Cell Design:Three Phases:• Understand the current condition• Analyze and make the conversion• Continuously Improve the process

Understanding the current state:

1. Look at the basic facts about the manufacturing area.

2. Use the Custom Profile Data Collection Forms to understand how the process is currently working.

• Custom Profile Collection Forms will be reviewed later in this session.

• Documenting the Current State:1. Basic facts on the current state (e.g. floor

space, WIP, etc)2. Product focus and quantity 3. Area/Process Mapping4. Time Observation 5. Takt Time

• These five steps of documentation give you a lot of information about how the process currently runs. Next we’ll work on improving it through cell design.

Analyze and Make the Conversion:

1. Determine cell opportunities• Review data; consider possible new plans as

well as issues

2. Design the cell• Make a plan, do the conversion, document it

for operators

3. Verify (move into cell)• Make the move, summarize the changes

• Questions:• How many operators does the process

require?• Could it run with fewer people by eliminating

the non-value added work?• Is anyone currently cross-trained to operate

more than one machine or station in the process?

• What kind of training might be needed to make a cell run smoothly?

Custom Profile Waste Elimination Data Sheets:

• Area Map/Process Map:– This form is used to document the process flow.

• Process mapping gives another picture of the workflow in an area.

• How are these forms going to be used at Custom Profile?– They’ll be used to flowchart the process in an

area. Which will allow you to document the current state.

Custom Profile Area Map Example

• Filling out the Area Map/Process Map:• Machine/activity layout sequence

– Process and material flow

• Location and Quantity of WIP• Safety precautions• Quality checks• Number and location of employees• Caution!!! Complete this in Pencil, the point is

to understand flow, not to be an artist!• This does not have to be to scale, to speed the

process of developing the Area Map.

• Raw Material Inventory:

• Inventory of material that has not undergone processing at a facility.

• The point of observing raw material is to minimize the amount in the manufacturing area.

• Time Observation Sheets:– Is a tool for documenting the time required for

each operation in the process.– Which includes:

• Waiting time• Walking time• Loading/Unloading• Un-wrapping• Installing • Etc…

• Filling out a Time Observation Form:– Video tape a minimum of five samples of each

operator involved in the process. • Trying to obtain this detailed information will be very

difficult without videotaping. • If possible try to tape different times of the day and

different operators performing the same operations. List all the operations in the proper sequence under

Description of Operation.

– Record each of the five time samples (in seconds) of each operation under #1-5. Take the average and record this number (in seconds) under AVG.

Make sure to record any tasks that don’t occur at every cycle.

Examples:• Machine Set-Ups• Un-packaging raw materials• Preventative Maintenance • Movement of Kanbans etc…

Mark down the average number of seconds of each operation which is value added time, Non value added and any machine cycle times.

• Examples of value added time:– Assembling, welding, machining, drilling, any function adding

value, Non value added and any machine cycle times.

• Examples of non value added time:– Unwrapping, wrapping, loading, unloading, movement of parts,

inspecting, delays, operators watching machines operate, reworking, reassembling, any functions not adding value for the customer.

• Machine cycle time is the time from when the ON button is pushed to when the machine stops its final movement. Loading and unloading are not included.

Custom Profile Time Observation Example

Process Analysis Sheet:• Floor Space used (sq. ft.)• Total Part Path (Linear Feet)• # of People• WIP• Value added/Non-Value added

Custom Profile Process Analysis Example

• Filling out a Work Balance Sheet:1. Heading Information:

• Part #: Fill in the part number for the process being documented.

• Process Name: Fill in the description of the operation being performed here.

• Analysis Date: Place the date when this work balance sheet was analyzed.

• Cell: Place the name of the cell that this operation is part of here.

• Quantity per shift: This is the amount of the part number listed in 1-a that will be made in a shift. (This number was needed to calculate the Takt Time for the Work Balance Sheet.)

• TAKT Time: This is the rate at which this part/assembly must be in order to meet customer daily demand.

• (Gap): This is difference between the operator’s cycle time and the TAKT Time for the part/assembly. (It must be a positive number if this sequence is to be able to supply the quantity required per day/shift.)

• Operator: Just as each machine is to be numbered, so are the operators. Place the number of operator here.

2. Sequence Number:• Fill in the sequence number assigned to each

specific component task that has been assigned to this operator in this column.

3. Description of Operations:• In as detailed as possible, enter the

description of the sequenced activity.• Use expressions made up of a present-tense

verbs and its direct object. (e.g. “press button”)

• Add in the machine number if it is available.

4. Time Elements:– Manual: Manual Work Time is the amount of operator activity

time for this sequence step as shown on the Time Observation Sheet.

– Auto: Automatic machine cycle time is the amount of unassisted machine cycle time. If the operator must attend the machine this should be consider manual time.

– Walk: Walking time is the it takes for the operator to move from one station to the next station. You should not distinguish between whether or not the operator is carrying anything or not. Round it off to the nearest second. Leave this space blank if there is no walking time assignable to this step.

– Total: Enter the total manual and walk times at the bottom of each column.

5. Cumulative Operating Time: (in secs.)• Indicate manual work time by a solid line.• Indicate machine time by a dotted line.• Indicate walking time by a wavy line.• Indicate waiting time by a double line.

6. TAKT Line:• Draw a red line vertically where the TAKT

Time is on the chart that is the same value as the TAKT Time in the header marked for this value.

Cycle Time Reduction/Setup Time Reduction

• STR/CTR• Set-Up Time: Is the time between the last good

part off one model/run and the first good part off the next model/run.

• Cycle Time: Is the amount of time required to progress from one defined point in a process to another. As long as a beginning and an end are specified.

• In a later session, we will be covering additional techniques for Set-Up & Cycle Time Reduction.

• TPM: Total Productive Maintenance– Is a technique for maximizing a production

systems efficiency (overall effectiveness).– It is a technique that aims at the elimination of

all accidents, defects, and breakdowns.– Equipment Downtime, Total Employee

Involvement