Common Formula of IE & Lean Tools

 

Common Formula of IE

1.      SMV               = Standard Minute Value

= Basic time + Allowance

= (Cycle time X Operator Rating) + Allowance

2.      SAM               =Standard allocated minutes.

=Basic time + Allowance.

3.   Target              = 

4.   Production      =

5.    Efficiency (%) =

=

=

6.    Achievement (%) =

7.    Average SMV =

8.   Balancing Loss (%)= 1 −

9.      NPT                 = Non Productive Time

10.  DHU               = Defect Per Hundred Unit

=

11. CPM                =

Overhead cost = (salary and wages, utility cost (electricity, water, gas), commercial cost, bank interest, machine depreciation, business promotion, house rent).

Available minute = (Operator + helper) ×hours in minute × working days × total line

·         CPM (Cost per minute)

·         CM (Cost of manufacturing)

·         SOP (Standard operating procedure)

·         GSM (Gram per square meter)

·         Lead time (Time between order taking to dispose)

Capacity Studies

The Capacity Study is used to:

o   Measure how long an operator is actually taking to perform an operation.

o   Calculate the operator’s potential performance over a full working day.

o   Compare this Capacity to Actual output.

o   To identify the bottle neck of the line.

Capacity Study Procedure:

o   Select the operation for capacity study.

o   Arrange the work places, methods, motions properly

o   Take cycle time using stop watch

o   At least 10 readings has to be taken

o   Calculate average time per pc garments

o   Add bundling time, m/c and Fatigue allowances for the time taken of that operation.

o   Calculate Capacity using the formula, Capacity (pcs/hr) = 60/ Time taken of an operation

Allowance:

An addition to basic time intended the worker with the opportunity to recover from the Physiological and psychological effects of carrying out specified work under specified Conditions to allow attention to personal needs.

The following are commonly used in garment operations:

Machine Type	MachineAllowance	Personal & Fatigue	Total allowance
Single Needle Lock Stitch	12.5 %	7.5%	20 %
Single Needle Chain Stitch	7.5 %	7.5%	15%
Double  Needle Lock Stitch	17.5 %	7.5%	25 %
Feed of the Arm	9.0%	7.5%	16.5 %
Over Lock 3Thread	7.5 %	7.5%	15 %
Over Lock 5 Thread	10.0 %	7.5%	17.5 %
Button Hole	5.0 %	7.5%	12.5 %
Button Stitch	5.0 %	7.5%	12.5 %
Bartack	5.0%	7.5%	12.5 %
Kansai 2 Thread	9.0 %	7.5%	16.5 %
Kansai 4 Thread	12.5 %	7.5%	20.0 %
Manual	2.5 %	7.5%	10 %

 

Follow up with Operators (Production study)

This is the process to follow the operator for certain time (like 1-hr), to get the actual idea of that operations.

It helps us to de-bottle neck the operation.

Setting the Time Standard

Time Standard (SMV) is used for individual operations are used for making the Operation Bulletin of a Garments.

To calculate the Standard Minute Value for an Operation 2-systems are used.

o   Time Study

o   GSD analysis

Time Study

It is used to set the Time standard of an Operation.

Operation Bulletin contains operations (how to be done), Machineries, Attachments, No. Of Work places, Manpower for individual Operation and to complete full garments, Individual Operational target and Line target, Line Balancing. So, it helps us to get complete idea for producing a garment.

Plant Layout (Line Layout)

It is the proper arrangement of the machineries in a production Line to get the Maximum productivity. Proper layout helps us to reduce the garments handling time.

SKILL MATRIX

1.       Can be used to identify required manpower during recruitment.

2.       Operator’s skill can be increased.

3.       To identify the potential worker move up to the higher position.

4.       Management awareness skill strength to product marketing.

5.       Supervisor can easily find replacement.

6.       To find an expert operator for critical operation.

7.       For line balancing.

8.       Serve as effective motivation for worker for the next skill grade.

Balancing

Balancing is a subject that relates to every decision taken on the production floor.

It is a system where you meet the production expectations and you can find the same amount of work in process in every operation at any point in the day.  To be able to achieve this is extremely difficult.

·         Keeping inventory costs low results in higher net income.

·         Keeping the line balanced lets the supervisors improve other areas because they can use their time better.

·         Balanced production keeps prices low which turns into repeat sales.

·         Balanced production means better production planning.

There are 3 rules for Balancing:

o   Have at least ½ hour of WIP for each operation

o   Solve problems before they become any larger

o   Meet production goals by keeping every operator working at their maximum capacity

 

Work In Process (WIP):

WIP is made up of all garments and their parts that are not completely finished.  For example a bundle of shirts that has everything attached but has no bottom hem.

1.       Investment in Inventory:

2.       Ability to Reduce the Production Cycle:

3.       Low throughput time permits better coordination between sales and production.            

How can we manage WIP?

1.       Production planning (Marketing and sales)

2.       Trims Control (Buttons, zippers, labels, thread, elastics etc.)

3.       Production Build-up (Considerations about loading the production lines, feed more causes overload)

4.       Balancing (Unbalanced production, absenteeism, turnover, change in style, bad cutting etc.)

5.       Cut Flow Control (FIFO- First in first out)

Bottleneck Analysis

Identify which part of the manufacturing process limits the overall throughput and improve the performance of that part of the process.Improves throughput by strengthening the weakest link in the manufacturing process.

KPI (Key Performance Indicator)

Metrics designed to track and encourage progress towards critical goals of the organization.

1. Factory Efficiency%
2. Man to Machine Ratio (MMR)

MMR =  =

3. Direct to Indirect ratio (DIR)

Direct labor means those who operate the machines and all others are considered as indirect labors.

4. Cut to Ship Ratio : (CSR)
5. Order to Ship Ratio: (OSR)
6. On Time Delivery Rate: (OTDR)
7. Average Style Changeover Time: (ASCT) 
8. Right First time quality (RFTQ): 
9. Quality to Production / Defects per Hundred Units (DHU) 
10. Nonproductive time ( NPT ): / Off Standard Time 
11. Plan hit rate (PHR) / Target achievement rate:
12. Line Cost per Minute ( CPM )

Method Study

Method Study is the systematic recording and critical examination of ways of doing things in order to make improvements.

The Method Study 8-step Procedure

1.       SELECT  (The Work to be studied)

2.       RECORD (Relevant information and data)

3.       EXAMINE (Relevant information and data)

4.       DEVELOP (The improved method)

5.       EVALUATE (Results of different alternative solutions)

6.       MAINTAIN (New method & Present it)

7.       DEFINE (New Method & train persons in applying it)

8.       INSTALL (Establish Control Procedures)

Introduction to Lean

The core idea of lean manufacturing is increasing production by eliminating waste from the manufacturing process.

So, what is waste? It can take many forms, but the basic idea is to eliminate anything and everything that does not add value from the perspective of your customer.

Another way to look at lean manufacturing is as a collection of tips, tools, and techniques (i.e. best practices) that have been proven effective for driving waste out of the manufacturing process.

Seven Deadly Wastes:

o   Over Production

o   Waiting

o   Transport

o   Motion

o   Over Processing

o   Inventory

o   Defects

Over Production:

Making something before it is truly needed. This is a particularly serious form of waste because it leads to excess inventory that is often used to mask other underlying problems and inefficiencies.

• Use a pull system to control how much is manufactured (Kanban).
• Reduce setup times so that smaller batches can be economically manufactured (SMED).

Waiting:

Time when work-in-process (WIP)is waiting for the next step of production.

• Design processes so that the flow is continuous and there are minimal (or no) buffers between steps in production (Continuous Flow).
• Use standardized work instructions to ensure that a consistent method and consistent times are used for each step of production (Standardized Work).

Transport:

Unnecessary movement of raw materials, work-in-process or finished goods.

• Design a linear, sequential flow from raw materials to finished goods (Value Stream Mapping).
• Make sure work-in-process is not placed into inventory (Continuous Flow).

Motion:

Unnecessary movement of people (movement that does not add value).

• Ensure that work areas are logically organized (5S).
• Consider alternate arrangements of equipment that reduce motion (Value Stream Mapping).

Over Processing:

More processing than is needed to produce what the customer requires. This is often one of the more difficult wastes to detect and eliminate.

• Compare customer requirements to manufacturing specifications (Kaizen).
• Look for potential simplifications to the manufacturing process (Kaizen).

Inventory:

Product (raw materials, work-in-process, or finished goods) quantities that go beyond supporting the immediate need.

• Bring raw materials in only as they are needed (Just-In-Time).
• Reduce or eliminate buffers between steps in production (Continuous Flow).
• Refer to Overproduction countermeasures (Kanban, and SMED).

Defects:

Production that is scrap or requires rework.

• Design processes so they are less likely to produce defects.
• Look for the single most frequent defect and determine why it occurs (Root Cause Analysis).
• Create work instructions to provide a consistent method of manufacturing (Standardized Work).

Lean Tools:

5 S:

Methodology for organizing, cleaning, developing, and sustaining a productive work environment.

• Sort (eliminate anything that is not truly needed in the work area)
• Set in Order (organize the remaining items)
• Shine (clean and inspect the work area)
• Standardize (create standards for performing the above three activities)
• Sustain (ensure the standards are regularly applied)

Poka-Yoke (Error Proofing):

Error Proofing is a structured approach to ensure quality and error free manufacturing environment. Error proofing assures that defects will never be passed to next operation.

 

 

JIT:

A philosophy of manufacturing based on planned elimination of all waste and continuous improvement of productivity. It encompasses the successful execution of all manufacturing activities required to produce a final product.

o   Highly effective in reducing inventory levels. Improves cash flow and reduces space requirements.

Kaizen:

The Japanese term for Continuous improvement; continuing improvement through involving everyone

Kanban:

Kanban is a simple parts-movement system that depends on cards and boxes containers to take parts from one workstation to another on a production line. The essence of the Kanban concept is that a supplier or the warehouse should only deliver components to the production line as and when they are needed, so that there is no storage in the production area.

o   Eliminates waste from inventory and overproduction.

One-Piece Flow:

One-piece flow or continuous flow processing is a concept means that items are processed and moved directly from one processing step to the next, one piece at a time. One-piece flow helps to maximum utilization of resources, shorten lead times, and identify problems and communication between operations.

Quick Changeover Time (QCO):

Quick changeover is a technique to analyze and reduce resources needed for equipment setup, including exchange of tools and dies.

Single Minute Exchange of Die (SMED)

SMED (Single-Minute Exchange of Dies) is a system for dramatically reducing the time it takes to complete equipment changeovers. The name Single-Minute Exchange of Dies comes from the goal of reducing changeover times to the “single” digits (i.e. less than 10 minutes).

Techniques include:

·         Convert setup steps to be external (performed while the process is running)

·         Simplify internal setup (e.g. replace bolts with knobs and levers)

·         Eliminate non-essential operations

·         Create standardized work instructions

Root Cause Analysis

A problem solving methodology that focuses on resolving the underlying problem instead of applying quick fixes that only treat immediate symptoms of the problem. A common approach is to ask why five times – each time moving a step closer to discovering the true underlying problem.

Standardized Work

Documented procedures for manufacturing that capture best practices (including the time to complete each task). Must be “living” documentation that is easy to change.