Just-in-Time/Total Quality Control Concept

Gaurav Awasthi

• What does an Organization strives for? – Maximize profit with minimum effort

• Just-in-Time is nothing but a tool and Philosophy to:– improve efficiency of the organization– Improve Quality– Reduce Wastage and throughput time– Reduce working capital requirement– Make organizations more responsive to customer

needs

Just Imagine…• To best understand the capabilities of JIT,

picture a pipeline running through a company.Payment to suppliers for Raw material

Payment by customers for products we ship

Time taken for Processing

Constraints in flowSetup time, Too much activity, wastage,

unwanted inventory

The GoalTo reduce processing time, remove constraints

Continuing Pipeline Analogy..

• Our goal is to reduce the processing time.• A fat pipeline allow us to make shipment

comfortably but very slowly.• A narrow pipeline speeds us up and allow us to

be more responsive to change.• But, Reducing Diameter Increase in velocity

uncovering of constraints• Hence, to further reduce the size of pipeline and

maintain flow we must remove the constraints.

Origins of JIT• Henry Ford with his application of assembly

line was the first to achieve JIT in 1920s.• He improved response time by producing a

simple, small, reliable car that many can afford.

• “People can have the Model T in any colour-so long as it's black” – Ford.

• By 1926 company could produce a car from Raw iron ore in 48 Hrs with 40% less price.

Origin continue…

• Ford offered only one model with one color to reduce inventory.

• When same concept was applied to more product variety, larger inventory couldn’t be avoided.

• After WWII Japanese took this concept to a whole new level.

• To remove the image of poor quality products Toyota refined this philosophy in accordance with Japanese national attributes of wisely using scarce resources.

How is it done? The Philosophy of JIT

• JIT is designed to continuously improve our ability to economically respond to change.

• Constraints occur and our attempts to increase throughput negatively affect quality, delivery or cost.

• The constraints appear in the form of wastes.• In JIT waste is defined as any activity that does not

add value for the customer• IT is the use of resources (manpower, equipment,

time) in excess of the theoretical minimum required.

Types of Wastes

• There are seven types of waste as defined by Shingeo Shingo:1. Waste of overproduction2. Waste of waiting3. Waste of transportation4. Waste of stocks5. Waste of motions6. Waste of making defects7. Waste of processing itself

Different aspects associated with JIT TQC

Work-in-progress is so less in JIT system because

Goods are assembled just before they are sold Subassemblies are made just before the product

are assembled

Components are fabricated just before subassemblies are made

To operate thus company must have1. People Involvement

The underutilized employee in JIT is also a waste. No blame game, teamwork. Supplier-customer partnership is important

2. Total Quality Concept-- Quality is everybody’s job: Marketing must

understand the specs well, Prod and R&D need to create economic process, HR train people and all should keep customer in mind.

-- The immediate customer: Customer is not outside the company. Every employee is the immediate customer for the previous in line.

-- Quality at Source: Every employee is trained in QC. They are empowered to even stop production.

3. The JIT Flow: No Queues: Queues hide

constraints and excessive queues should be reduced to improve responsiveness.

Queues in front of Raw material, WIP, finished goods are all waste. Often cost of holding them are much higher but hidden.

Elements that supports JIT Flows• A major advantage of JIT is to have right item

at the right place and at the right time.• So, purchase and produce items only short

time before they are needed so that WIP inventory is low.

• This helps in:– Increased throughput– Decreased WC requirements– Reduce need for floor space– Save time– Increase responsiveness

JIT Flow support factors continued.. 1. Focused Factories: factories which produce less

variety, keep subassemblies in inventory and variety producing factories define standards carefully and use common components in multiple products.

2. Uniform Production Rate: Objective is to achieve smooth synchronized flow at uniform rate. When unexpected large numbers are required, production is stepped up gradually one-at-a-time.E.g. A,B,C are needed 300, 200, 100 so they are produced in sequence A, B, A, B, A, C rather than producing lots of As. This is called Mixed Model Assembly.

3. Pull v/s Push Method of Co-ordinating work Centers: Coordinating assembly for complex and variety production is tough. There are two approaches for this:

(a) Push Method: – Production control center schedule necessary

quantity of Raw material– Material is pushed to work center– When work is done at WC1 parts wait till WC2 is

ready– Eventually all components and subassemblies are

pushed to final assembly

(b) Pull Method:– Each WC holds some designated no of containers– It does not produce any more till a full container is pulled

by some downstream WC.– The WC works only to replace items pulled.– Production rate is kept constant for say 1 month or 3

months using mixed model assembly.

Master Schedule

Explosion of Bill of material

Finished Assembly Schedule

Component Supplier

Product Final Assembly Area

Assembly Production

Component Fabrication

Material Supplier

Product Shipment

4. The Kanban System: – The name comes from Japanese and means Card.– It is a simple information system.– M Card is used to signal supplier WC to send a

container of item– P Card is used to authorize the supplier WC to

manufacture another container

5. Production and Precurement in small lots: – A minimum feasible lot size is estimated and

contained in small boxes which contains say 1 hr of prod

– It is replaced by as much if not more to keep inventory low.

6. Quick Inexpensive steps:• To make small lots work well, employees need to do

setups quickly and inexpensively.• Since they do it frequently they become good at it.• Use of standard equipments, quick release clamps,

few movements are few tricks.7. High Quality Levels:• Batch size is small so low quality cant be tolerated• Workers should quickly point out where problem

occurred and rectify it quickly8. Continuous Improvement: • Manager may remove one Kanban at a time and see

process effects• Each team could have an idea card for which manager

has to respond in 48 hours.

The Philosophy of Total Quality Control

JIT & TQC

• JIT and TQC are two sides of the same coin.

• On one hand, JIT exposes the problems, TQC on the other hand is the tool to understand and eliminate the constraints.

“Total”, “Quality” and “Control” Defined

• Quality is defined as meeting customer specifications and reducing the variability around the target value

• Total applies to all levels of employees, all functions, all processes, all outputs and inputs and all suppliers and customers

• Control is our ability to make process behave as we intend to

The Process of TQC

Plan

Do

Check

Act

• Plan:– Describe the problem– Theme of the problem

• Do – Current Situation: Describe the current situation

well– Analyze: • Where are the threats and opportunities• What is happening v/s what should be happening• What is causing the problem• What are the alternatives• What are the risks• What resources needed• Apply new thinking and counter measures

• Check: Measure effectiveness of the current situation

• Action: – Standardization: Redefine the documentation– Future Plans: What can be done to prevent this

from happening in the future

Thank You