Muthu Naveen S

-maximizing profits by reducing waste…

What is lean?? Fundamental objective:

To create the most value while consuming the fewest resources.

How is the objective accomplished?

Lean production is aimed at the elimination of waste in every area of production while producing top quality products in the most efficient and economical manner possible

SEVEN TYPES OF WASTE

WASTE

- one that adds no value to product

TYPES

• Waste due to over production

• Waste due to waiting time

• Waste due to transportation

• Waste due to processing

• Waste due to inventory

• Waste due to motion

• Waste due to defects

LEAN MANUFACTURING PRINCIPLES

cell design (takt) • team roles/resp/rules • kanban • work instruction • 5s housekeeping • one piece flow

SMED • Poka-yoke • TPM • SPC • Continuous improvement

Mix Model manufacturing • FMEA • DFMA • Process Capability • Make to order

CELL DESIGN

Arrangement of resources

Improve process flow & eliminate waste

Design considerations :-

•Adaptation of process to fit takt time

• Reduce material and operator movement

• Eliminate storage, multiple handling, wait time

• Material flow in one direction only

• Layout machines by process sequence

Takt Time = Demand Rate

Takt Time = Work Time Available

1200 Seconds

120 Boards = 10 Sec/Board Takt Time =

Cycle Time

Takt Time = Minimum no of Cells

Number of Units Sold

TAKT TIME

Optimize the Bottlenecks

•Reduce batch sizes

–Eliminate uneven amounts of work

•Put the best people on the bottlenecks

–They set the pace

0

5

10

15

20

A B C D E

Operation

Unbalanced Line

0

5

10

15

20

A B C D E

Operat ion

Balanced Line

Takt Time = 10 seconds

BALANCED PROCESS

Inv Inv

Inv

Inv

C

D E

B Inv A

A

Inv A

A Inv

A

Inv

Inv

Inv

Inv B

B

Inv Inv B Inv

C

C

C

C

Inv

Inv Inv Inv Inv

E

E

E

D

D

D

D

Dept “A” Dept “B” Dept “C”

Dept “E” Dept “D”

D E

C

B A

D E

C

B A

Stage 1

Production in Specialized Departments

Stage 2

Production in Product Cell

Stage 4

Production in Compact Cell with One-Piece Flow and

Separation Man/Machine

Stage 3

Production in Compact Cell with One-Piece Flow

CELL LAYOUT

5S – HOUSEKEEPING

1s - Seiri (Sorting)

2s - Seiton (Straighten or Set in Order)

3s – Seiso (Shine)

4s - Seiketsu (Standardizing)

5s - Shitsuke (Sustaining)

BEFORE 5S AFTER 5S

•Push System

–Resources are provided to the operator based on forecasts or schedules

•Pull System

–A method of controlling the flow of resources by replacing only what has been consumed

PUSH Vs. PULL SYSTEMS

Pull System Flow Diagram

Information Flow

Supplier

Raw

Matl Process

A

Process

B

Fin.

Goods

Kanban

Locations

Process

C Customer

Parts Flow

Definition: Minimizing the time from last good piece of the current product run to first good piece of the next (different) product run

SINGLE MINUTE EXCHANGE OF DIES (SMED)

Separate Internal and

External Setup

Convert Internal Setup to

External Setup

Streamline Internal and

External Elements

Three stages

Transition Steps to Quick Changeover

Preliminary Step 1 Step 2 Step 3

Internal and

External Setup not

differentiated

Separate Internal

and External

Setup

Convert Internal

Setup to External

Setup

Streamline all

aspects of Setup

operations

Ext

Int

Ext

Int

Ext

Ext

Int

Int

Ext

Int

Ext

Int

Pear-Shaped Hole Method

Tighten Here

Attach and

Remove Here

POKA-YOKE

Poka-yoke is a Japanese term that means "fail-safing", "Foolproof" or "mistake-proofing". It is a method of preventing errors by putting limits on how an operation can be performed in order to force the correct completion of the operation.

The three types of poka-yoke are: The contact method which identifies defects by whether or not

contact is established between the device and the product. Color detection and other product property techniques are considered extensions of this.

The fixed-value method which determines whether a given number of

movements have been made. The motion-step method which determines whether the prescribed

steps or motions of the process have been followed

Guide Pins and Cutouts (that limit orientation)

CutoutGuide Pins

Correctly Oriented Incorrectly Oriented

Example - 1

Example - 2

Total Productive Maintenance

Total Productive Maintenance (TPM) is an equipment management program that emphasises operator involvement and ownership of equipment performance.

Goals of TPM:

• Improving equipment effectiveness

• Improving maintenance efficiency and effectiveness

• Early equipment management and maintenance prevention

• Training to improve the skills of all people involved

• Involving operators in routine maintenance

Pillars of TPM

Productivity: – Increases • * Labor & productivity. * Value added per person. * Rate of operation. – Reduces • * Breakdowns.

Cost: Reduction in * man power. * maintenance cost and * conservation of energy.

Delivery: Reduced stock Inventory turn over increased. Quality:

– Reduces • * Defects of in-process material. * Defects in processed material.

Safety: Zero accidents. Zero pollution.

Benefits of TPM

FAILURE TAGS

FAILURE MODE AND EFFECTS ANALYSIS

A failure modes and effects analysis (FMEA) is a procedure for analysis of potential failure modes within a system for classification by severity or determination of the effect of failures on the system

Why we use FMEA?

•Increase probability of DETECTION

•Identify biggest contributor to failures

and eliminate them

•Reduce probability of failure occurring

•Build quality into the product & process

Preparation FMEA Process Improvement

a. Identify the ways in which process inputs can vary (causes) and identify associated FAILURE MODES. These are ways that critical customer requirements might not be met. b. Assign severity, occurrence and detection ratings to each cause and calculate the RISK PRIORITY NUMBERS (RPNs). c. Determine recommended actions to reduce RPNs. d. Estimate time frames for corrective actions. e. Take actions and put controls in place. f. Recalculate all RPNs.

• Tackle highest RPN’s first • Reduce the occurrence • Improve the detection • Where possible apply mistake proofing techniques. • Note :- Mistake proofing process will result in either lower occurrence or detection rankings • Standardization across all products or processes • Employ PDSA cycle

NECESSARY ACTIONS

Design For Manufacture and Assembly (DFMA)

DFMA is a proactive and concurrent design process that allows for early consideration of manufacturing aspects The purpose is to generate an environment where a cross-functional team works together to optimize the design for cost effective manufacturing It is established by design and manufacturing engineers working together

Minimize the number of parts Minimize the number of fasteners Avoid difficult components Use modular subassemblies Use multifunctional parts Minimize reorientation Use self-locating features Avoid special tooling/test equipment Provide accessibility Minimize operations & process steps

DFMA Principles

Bushes are integral to the base Snap-on plastic cover replaces standoff ,cover ,plastic bush, six screws. Using pilot point screw to fix the base, which redesign to be self-alignment.

CONCLUSION

Lean

• Simple and Visual

• Demand Driven

• Inventory as Needed

• Reduce Non-Value-Added

• Small Lot Size

• Minimal Lead Time

• Quality Built-in

• Value Stream Managers

Traditional

• Complex

• Forecast Driven

• Excessive Inventory

• Speed Up Value-Added Work

• Large Batch Production

• Long Lead Time

• Quality Inspected-in

• Functional Departments

Ultimate aim of lean – “better production with fewer resources”

Got Any Questions??