Monday, May 25, 2009

Student Notes

Total Quality Management
Tapen Gupta , Guru Nanak Institute of Mnanagement

Total Quality Management
Practiced in 1980’s
Involvement of entire organisation from top to bottom
Key elements
Management commitment
Customer involvement
Employee involvement
Leadership & strategic planning
Quality is ……….
Q ----------- Quest for excellence
U ----------- Understanding customer need
A ----------- Action to achieve customer
satisfaction
L ----------- Leadership (determination to be
a leader)
I ----------- Involvement of all people
T ----------- Team spirit to work
Y ----------- Yardstick to measure progress

Quality
Sum total of features of a product which influence its ability to satisfy a given demand
“Quality of product or service is a customer’s perception of the degree to which the product or service meets his or her expectations”

What is quality
Quality is
Conformance to specification
Conformance to requirement
What the customer think it is
Combination of feature & design
Value of money
Ability of a product to meet customer’s need

Eight dimensions
Performance
Features
Reliability
Serviceability
Aesthetics (Appearance)
Durability
Customer service
Safety

Ten Dimension of service quality
Reliability
Responsiveness
Competence
Access
Courtesy (politeness)
Communication
Credibility
Understanding

Benefits of quality
Gives positive company image
Improves competitive ability
Increase market share & net profits
Reduced costs
Reduces product liability problem
Improves employees morale
Improves productivity
Customer driven definition
Conformance to specification (Requirement)
Value of money
Fitness to use
Support provided by seller (customer services)
Psychological impression (image , aesthetics)
Determinants of quality
Quality of design
Quality capability of process
Quality of Conformance
Quality of customer services
Organization quality culture

Quality Management
Inspection to ensure quality (in early 1900s)
Statistical quality control (in 1940s)
Total quality control (1960’s onwards)
TQM means:
Top management commitment to quality
Customer involvement and focus
Employee involvement and focus
Leadership & Strategic planning
Company wide quality culture
Continuous improvement
Quality control…..
Setting quality standards
Appraisal of conformance
Taking corrective actions
Planning for quality improvement
Principles of total quality
Focus on the customer (both internal & external)
Participation and team work
Employees involvement
Continuous improvement

Total quality control….
Integration quality development
Quality maintenance
Quality improvement
Efforts of various groups in organization
TQM…..
A philosophy that involves everyone in a organization in a continual effort to improve quality and achieve customer satisfaction
Six basic concepts
To management commitment
Focus on both internal & external customer
Employee involvement
Continuous improvement
Partnership with suppliers
Establishing performance measure for processes

8 Essentials …..
Customer satisfaction
Leadership
Quality policy
Organization structure
Employee involvement
Quality costs
Supplier selection and development
Recognition and reward
Principles
Strive for quality in all things
The customer is the creation of quality
Improve the process or system by which product are produced
Quality improvement is continuous
Workers involvement
grouped decision
Team work and cooperation
Scope ……
Are integrated organizational infrastructure
A set of management practices
A wide variety of tools and techniques

Quality Gurus
W. Edwards deming (USA)
Higher quality means lower cost
Quality means continuous improvement
14 points of quality management
Seven deadly diseases and sins
Deming wheel
Deming triangle
Deming prize
14 points
Create constancy of purpose for continual improvement of product/services.
Adopt the new policy for economic stability.
Cease dependency on inspection to achieve quality.
End the practice of awarding business on price tag alone.
Improve constantly and forever the system of production and service.
Institute training on the job.
Adopt and institute modern method of supervision and leadership.
14 points
Drive out fear. (Fear of failure, fear of change etc).
Breakdown barriers between departments and individuals.
Eliminate the use of slogans, posters and exhortations.
Eliminate work standards and numerical quotas.
Remove barriers that rob the hourly worker of the right to pride in workmanship.
Institute a vigorous program of education and retraining.
Define top management's permanent commitment to ever improving quality and productivity.

Deming's Seven Deadly Diseases and Sins
Lack of constancy of purpose (short-term quality programs)
Emphasis on short-term profits
Over reliance on performance appraisals
Mobility of management (job hopping)
Over emphasis on visual figures
Excessive medical costs for employees healthcare
Excessive costs of warranty and legal costs.
Deming Wheel/Deming Cycle/P-D-C-A Cycle
P - Plan (process) the improvement
D - Do Implement the plan
C - Check - Check how closely result meets goals
A - Act - Use the improved process as standard practice
Deming Prize
Awarded by the union of Japanese Scientists and Engineers U USE) to a firm or its division based on the distinctive performance improvements achieved through the application of Company Wide Quality Control (CWQC).

Joseph Juran (USA) (Professor and Quality consultant - wrote 12 books on quality including Quality Control Hand Book)
Defined quality as “fitness for use".
Philosophy:
(a) Top management commitment,
(b) Costs of quality,
(c) Quality triology,

(d) 10 steps for quality improvement,
(e) Universal breakthrough sequence

Costs of Quality
Prevention costs: Costs of quality planning, new product review, training, process planning, quality data and improvement projects.
Appraisal costs: Costs of incoming inspection, process inspection, finished goods inspection, quality laboratories and calibration of instruments.
Internal failure costs: Costs of scrap, rework, down grading (seconds quality products) retest, downtime.
External failure costs: Costs of warranty, returned goods, customer complaints, allowances to customers for substandard quality products.
Costs of quality can be reduced by revising the production system including technology, management, attitudes and training
Quality Triology
(i) Quality planning,
(ii) Quality control and
(iii) Quality improvement.
Quality Habit Establish specific goals Establish plans for achieving these goals Assign clear responsibilities to employees Base rewards on results.
Elements of TQM Concept
Sustained top management commitment to quality
Focus on Customer requirement and expectations
Preventing defects rather than detecting them
Recognising that responsibility for quality is universal
Quality measurement
Continuous improvement (Kaizen) approach
Root-cause corrective action
Employee involvement and empowerment
Elements of TQM Concept
Synergies of Team work
Process improvement (Continuous Improvement - Kaizen, 6 cr - Quality, Break-through
Improvement, Reengineering)
Thinking statistically
Bench marking
Inventory reduction UIT)
Value improvement (Value analysis, cost reduction) [value = performance]
- Cost
Supplier partnership
Quality training for all
Business process reengineering (Break-through improvement





























Tapen Gupta , Guru Nanak Institute of Management

Capacity Planning
What is Capacity?
Capacity is the ability to deliver in a defined time
To have capacity a system must have some of each of the necessary transforming resources for the operation
Both input and output measures can be used:
Output measures are usual for high-volume, standardised processes, e.g.:
Automotive production line: number of cars per week
Hotel room service: number of guests served per hour
Call centre: customer calls per hour
Input measures are usual for low-volume, flexible processes and for many service operations , e.g.
Hospital: beds available
Law firm: hours
Utilisation is also a useful capacity measure, it is defined as:
average output rate/maximum capacity x 100%


Ability to deliver …
Capacity is the maximum output rate of a production or service facility and capacity planning is the process of establishing the output rate that may be needed at a facility
Capacity is the upper limit or ceiling on the load that an operating unit can handle.
The basic questions in capacity handling are:
What kind of capacity is needed?
How much is needed?
When is it needed?

In general, production capacity is the maximum production rate of an organization.
Capacity can be difficult to quantify due to …
Day-to-day uncertainties such as employee absences, equipment breakdowns, and material-delivery delays
Products and services differ in production rates (so product mix is a factor)
Different interpretations of maximum capacity


The Federal Reserve Board defines sustainable practical capacity as the greatest level of output that a plant can maintain …
within the framework of a realistic work schedule
taking account of normal downtime
assuming sufficient availability of inputs to operate the machinery and equipment in place
Factors Affecting Capacity Planning
Importance of Capacity Decisions
Impacts ability to meet future demands
Affects operating costs
Major determinant of initial costs
Involves long-term commitment
Affects competitiveness
Affects ease of management
Globalization adds complexity
Impacts long range planning
Capacity
Design capacity
maximum output rate or service capacity an operation, process, or facility is designed for
Effective capacity
Design capacity minus allowances such as personal time, maintenance, and scrap
Actual output
rate of output actually achieved--cannot exceed effective capacity.
Efficiency and Utilization
Efficiency/Utilization Example
Actual output = 36 units/day
Efficiency = = 90%
Effective capacity 40 units/ day


Utilization = Actual output = 36 units/day
= 72% Design capacity 50 units/day
Determinants of Effective Capacity
Facilities
Product and service factors
Process factors
Human factors
Operational factors
Supply chain factors
External factors
Measurements of Capacity
Output Rate Capacity
For a facility having a single product or a few homogeneous products, the unit of measure is straightforward (barrels of beer per month)
For a facility having a diverse mix of products, an aggregate unit of capacity must be established using a common unit of output (sales dollars per week)
Measurements of Capacity
Input Rate Capacity
Commonly used for service operations where output measures are particularly difficult
Hospitals use available beds per month
Airlines use available seat-miles per month
Movie theatres use available seats per month


Measurements of Capacity
Capacity Utilization Percentage
Relates actual output to output capacity
Example: Actual automobiles produced in a quarter divided by the quarterly automobile production capacity
Relates actual input used to input capacity
Example: Actual accountant hours used in a month divided by the monthly account-hours available

Measurements of Capacity
Capacity Cushion
an additional amount of capacity added onto the expected demand to allow for:
greater than expected demand
demand during peak demand seasons
lower production costs
product and volume flexibility
improved quality of products and services
Forecasting Capacity Demand
Consider the life of the input (e.g. facility is 10-30 yr)
Understand product life cycle as it impacts capacity
Anticipate technological developments
Anticipate competitors’ actions
Forecast the firm’s demand
Other Considerations
Resource availability
Accuracy of the long-range forecast
Capacity cushion
Changes in competitive environment
Expansion of Long-Term Capacity
Subcontract with other companies
Acquire other companies, facilities, or resources
Develop sites, construct buildings, buy equipment
Expand, update, or modify existing facilities
Reactivate standby facilities
Reduction of Long-Term Capacity
Sell off existing resources, lay off employees
Mothball facilities, transfer employees
Develop and phase in new products/services
Key Decisions of Capacity Planning
Amount of capacity needed
Timing of changes
Need to maintain balance
Extent of flexibility of facilities
Steps for Capacity Planning
Estimate future capacity requirements
Evaluate existing capacity
Identify alternatives
Conduct financial analysis
Assess key qualitative issues
Select one alternative
Implement alternative chosen
Monitor results
Make or Buy
Available capacity
Expertise
Quality considerations
Nature of demand
Cost
Risk

Developing Capacity Alternatives
Design flexibility into systems
Take stage of life cycle into account

Take a “big picture” approach to capacity changes
Prepare to deal with capacity “chunks”
Attempt to smooth out capacity requirements
Identify the optimal operating level
Economies of Scale
Economies of scale
If the output rate is less than the optimal level, increasing output rate results in decreasing average unit costs
Diseconomies of scale
If the output rate is more than the optimal level, increasing the output rate results in increasing average unit costs
Planning Service Capacity
Need to be near customers
Capacity and location are closely tied
Inability to store services
Capacity must be matched with timing of demand
Degree of volatility of demand
Peak demand periods
Cost-Volume Relationships
Cost-Volume Relationships
Cost-Volume Relationships
Assumptions of Cost-Volume Analysis
One product is involved
Everything produced can be sold
Variable cost per unit is the same regardless of volume
Fixed costs do not change with volume
Revenue per unit constant with volume
Revenue per unit exceeds variable cost per unit
Financial Analysis
Cash Flow - the difference between cash received from sales and other sources, and cash outflow for labor, material, overhead, and taxes.
Present Value - the sum, in current value, of all future cash flows of an investment proposal.
Factors which favors over capacity
Where there is an economic capacity size below which process is uneconomic
Building capacity is not so costly
Buying outside is not feasible
Lead time to add capacity is long
Lost sales are viewed very negatively by trading cycles
Factors which favors addition of capacity on conservative basis
Alternative capacity planning are easily available
Build up cost of capacity is low
Lead time to build new capacity is short
Lost of sales have no disastrous
Problems in capacity planning
There is no standard terminology
Every vendor has a different definition of capacity management, capacity planning, sizing, tuning, and so on.
Some vendors use the term capacity management to include both capacity planning and tuning. Others use it to denote tuning only.
There is no standard definition of capacity
One definition is in terms of maximum throughput.
Jobs per second, transactions per second (TPS), Instructions per second (MIPS) or bits per second.
Another definition: Maximum number of users that the system can support while meeting a specified performance objective.
Capacity planning is expressed in workload units.
Users, sessions, tasks, activities, programs, jobs, accounts, projects and so on.
There are number different capacities for the same system
Nominal capacity, usable capacity, and knee capacity
Other terms: practical capacity (usable capacity) and theoretical capacity (nominal capacity)
Problems in capacity planning…
There is no standard workload unit.
In case of users or sessions it is difficult to characterize the workload that varies from one environment to another environment.
So workload independent measures such as MIPS are still popular for forecasting.
Forecasting future applications is difficult
Most of the forecasting is based on the assumption that the future trend will be similar to the past.
This assumption is violated if new technology suddenly emerges.
There is no uniformity among systems from different vendors.
The same workload takes different amounts of resources on different systems.
This requires developing a vendor independent benchmark and running it on different systems.
Model inputs cannot always be measured
Simulation and analytical models are used to predict the performance under different alternatives.
Sometimes the inputs required for the model are not accurately measurable.
Think time is commonly used in analytical models, but it is impossible to measure think time.
Problems in capacity planning…
Validating model projections is difficult.
There are two types of model model validations: baseline validation and projection validation.
Baseline validation requires that using the current workload and configuration in the model and verifying that the model output matches the observed system performance.
Projection validation, requires changing the workload and configuration and verifying that the model output matches the changed real system performance.
Project validations are rarely performed so the model for capacity planning is suspect.
Distributed environments are too complex to model
Initial computer systems consisted of only a few components.
Justifying the cost of each component was simple.
With distributed environments of today the system consists of a large number of semi autonomous clients, servers and network links, and I/O devices.
Workstation usage is very different from others and interactions are rather complex.
It is difficult to justify the cost of each component.
Problems in capacity planning…
Performance is only a small part of the capacity planning problem.
The key issue in capacity planning is cost
Cost of the equipment, software, installation, maintenance, personnel, floor space, power, and climate control (cooling, humidity control).
Performance modeling helps only in sizing the equipment.
As the cost of computer hardware is declining, the other costs have become a major consideration in cap city planning.
Capacity planning is an important problem faced by computer installation manager
Number of capacity planning tools are available in the market.
Include workload analyzers that understand accounting logs
Some also have built-in monitors














































Tapen Gupta , Guru Nanak Institute of Management

What we plan to do about breakdowns of machines?

what steps are we going to take to prevent the breakdowns?


Preventive maintenance before breakdown
Maintenance after break down happens
Preventive maintenance reduces the no of breakdowns

Maintenance Management
Efficiency of the production function
Solely depends upon the functional reliability of the production facilities
Which are nothing but a package of land ,building ,plants & equipment , tools & plant services
Such as material handling , power plant , gas & steam lines, water supply , fire fighting facilities.
Subject to wear & tear

What is maintenance
Function of production management that is concerned with the day to day problem of keeping the physical plant in good operating condition
It is necessary to ensure the availability of the machines , building & services needed by the other parts of the organization for the performance
Maintenance Management
Maintenance management is concerned with the direction& organization of resources in order to control the availability & performance of the industrial plant to some specified level
Keeping machinery , equipment and plant services in proper condition

Scope of Maintenance
Machines break down
Parts wear out
Building deteriorate over a period of time
Maintenance covers two broad categories functions
Primary functions
Secondary function
Primary function
Maintenance of existing plant and equipments
Maintenance of existing plant building and grounds
Equipment inspection and lubrication
Utilities generation and distribution
Alteration to existing equipments
New installations of equipments

Secondary functions
Storekeeping
Plant protection including fire protection
Waste disposal
Salvage
Property accounting
Pollution and noise control

Importance of maintenance mgt.
Competitive edge and customer services
Quality assurance
Avoid the danger of losing market share
Cost control

Impact of poor maintenance
Reduced production capacity
Rise labour cost
Poor product & service quality
Injuries to employee
Injuries to customer
Customer satisfaction



Objectives of maintenance mgt
Minimizing the loss of productive time
Minimizing the repair time
Minimizing the loss due to production stoppages
Prolonging the life of capital asset
Keep all productive assets in good working condition
Improve quality of goods
Minimize accidents

Areas of maintenance
Civil Maintenance : water , gas , steam , compressed air , heating etc
Also include house keeping , scarp disposal , fencing , Gardening, lawns etc.
Mechanical maintenance : transport vehicles , MH equipment , boilers etc
Electrical : generators, transformers ,motors , telephones , lighting, fans etc
Type of maintenance
Break down maintenance
Preventive maintenance
Predictive maintenance
Routine maintenance
Planned maintenance
Planning & scheduling mgt
Maintenance planning seeks answer to the following question:
What maintenance activities to be carried out?
How these activities to be carried out?
Where these activities are to be performed?
why these activities are to be performed?
When these activities are to be performed?


Maintenance planning steps
Know the equipment
Establish the priorities
Investigate the maintenance work
Develop the repair plan
Prepare the list of maintenance material
Prepare the list of specific tools
Estimate the time requirement
Provide the necessary safety devices

Scheduling maintenance work
Scheduling indicates what maintenance work has to be carried out when & also in what sequence the work to be done
Who should do the maintenance works which are already planned?
When the maintenance work has to be done?
Reasons for maintenance sch.
Utilize the maintenance crew effectively
Utilize the maintenance equipments & tools effectively
Reduce the interruption in production
Reduces abrupt breakdown

















Material Handling Systems
Tapen Gupta Guru Nanak Institute of Management
Material Handling
Right Definition
Material handling uses the right method to provide the right amount of the right material at the right place, at the right time, in the right sequence, in the right position, in the right condition, and at the right cost.
This is a relatively broad definition of material handling.
Material handling ...
involves handling, storing, and controlling material
adds value through time and place utility
impacts space requirement, profits, quality, safety, and productivity


Material Handling
Material handling adds COST, but not VALUE.
as much as 60% of total production cost
20%-30% of direct labor costs
50%-70% of indirect labor costs
What’s the best way to handle materials?DON’T!!
Goal: MINIMIZE COSTS OF MATERIAL HANDLING
Material Handling System Equation
The Twenty Principles of Material Handling
Orientation Principle: Study the system relationships thoroughly prior to preliminary planning in order to identify existing methods and problems, physical and economic constraints, and to establish future requirements and goals.
Planning Principle: Establish a plan to include basic requirements, desirable options, and the consideration of contingencies for all material handling and storage activities.
Systems Principle: Integrate those handling and storage activities which are economically viable into a coordinated system of operation including receiving, inspection, storage, production, assembly, packaging, warehousing, shipping and transportation.
4.Unit Load Principle: Handle product in as large a unit load as practical4.
5.Space Utilization Principle: Make effective utilization of all cubic space.
Standardization Principle: Standardize handling methods and equipment wherever possible.
Ergonomic Principle: Recognize human capabilities and limitations by designing MH equipment and procedures for effective interaction with the people using the system.
Energy Principle: Include energy consumption of the MH systems and material handling procedures when making comparisons or preparing economic justification.
Ecology Principle: Minimize adverse affects on the environment when selecting MH equipment and procedures.
Mechanization Principle: Mechanize the handling process where feasible to increase efficiency and economy in the handling of materials.
Flexibility Principle: Use methods and equipment which can perform a variety of tasks under a variety of operating conditions.
Simplification Principle: Simplify handling by eliminating, reducing, or combining unnecessary movements and/or equipment.
. Gravity Principle: Utilize gravity to move material wherever possible, while respecting limitations concerning safety, product damage and loss.
Safety Principle: Provide safe MH equipment and methods which follow existing safety codes and regulations in addition to accrued experience.
Computerization Principle: Consider computerization in MH&S systems, when circumstances warrant, for improved material and information control.
System Flow Principle: Integrate data flow with the physical material flow in handling and storage
Layout Principle: Prepare an operational sequence and equipment layout for all viable system solutions, then select the alternative system which best integrates efficiency and effectiveness.

Cost Principle: Compare the economic justification of alternate solutions in equipment and methods on the basis of economic effectiveness as measured by expense per unit handled
.19 Maintenance Principle: Prepare a plan for PM and scheduled repairs on all material handling equipment.

Obsolescence Principle: Prepare a long range and economically sound policy for replacement of obsolete equipment and methods with special consideration to after-tax life cycle costs.


Selecting Material Handling Methods
Systematic Approach

Define the problem
2.Analyze the problem
Observe activities
Obtain layouts, flow patters, schedules, etc.
Obtain information on existing material handling equipment
Analyze situation by material handling equation, Twenty Principles of Material Handling, and/or forms such as Basic Data Form (see insert)
Can activities be combined, simplified, eliminated???

Identify possible solutionsOrganize meeting with:
material handlers
machine operators
supervisors
support engineers
4. Evaluate alternatives Meet again to rate alternatives using Factor Analysis



Comprehensive MH Program
Not considered isolated but in context of following factors:
Type of product
Plant layout
Type of production system
Factory building
Production planning & control
Packaging
Material handling equipment

Improvement of MH Systems
Cellular Manufacturing
Eliminate Handling
Eliminate Storage
Eliminate Inventory
Eliminate waste due to poor quality
KEYS:
Efficient layout, scheduling, problem prevention
Types Of Material Handling Equipments
Lifting , holding , dropping
Loading , Unloading
Positioning
Moving

Types of equipment
Cranes and hoists
Conveyors
Trucks , tractors and trailers
Rails
Rope ways
pipelines
Types of services
Lifting ,Moving , positioning , stacking
Conveyor Systems

Roller Conveyor (Silindirli Konveyor)
Belt Conveyor (Bant Konveyor)
Wheel Conveyor Tekerlekli Konveyor
Chain Conveyor (Zincir Konveyor)

Chute Conveyor (Kaydirakli Konveyor)
A chute conveyor is a slide, generally made of metal, which guides materials as they are lowered from a higher-level to a lower-level workstation. The shape of the chute can be straight or spiral to save space.



Hoist (Palanga)

Stacker Crane (Istifleme Vinci)
Hand Carts/Trucks (El Arabalari/Kamyonlari)



Advantages of Good MHS
Minimizes the movement of material
Eliminates unproductive handling
Reduces idle machine capacity
Reduces idle time of labour
Inc the safety
Quality of material
Greater economy in store room
Effective productive control











































Plant Layout
Tapen Gupta Guru Nanak Institute of management

Definition & Objectives
Planning the optimum arrangement of facilities, personnel, equipment, storage space, material handling equipment and all supporting services, along with the design of the best structure to contain all these facilities
Economic handling of all material; better supervision; faster production; better product quality; flexible plant & workspace design for expansion; Improved work conditions; unidirectional workflow

Activities Classification
Office area
Plant area
Production department
Services department
Technical services
Personal services
Technical services
Receiving department
Store room
Stock room
Tool room
Inspection department
Power house
Material handling
Shipping department


Personal services
Parking area
Timekeeper office
Canteen & lunch room
Recreation room
toilets
THE NEED FOR GOOD FACILITIES PLANNING
Plant facilities influence operating costs and profits.
Planning allows facilities and its operations (ISO 14001, etc.) to comply with laws and/or regulations.
Facilities are fixed investments involving high capital-cost expenditures.
Facilities are inflexible and long term commitments.
The planning, design and construction of facilities require long lead times.
Good planning helps to avoid disruptions in production and shipping or delivery.
The quality of facilities influences the attitudes of and the ability to attract suitable employees.
Industrial facilities must be planned to meet anticipated future requirements yet compete profitably today.
Facilities need to be planned for an appropriate degree of flexibility, expandability, versatility…
Good plans help management to take advantage of business opportunities that arise.
Good planning is an aid to obtain approval and financing monies.
Good planning reduces the high materials handling $ resulting from “ad hoc” expansion of plant facilities.

Ideal plant layout
Acc to F. G. Moore
“A Good plant layout is one which allows material rapidly & directly for processing . This reduces transport handling, clerical and other costs down per unit , space requirement are minimised and it reduces idle machine and idle man time”
Advantages
Better working conditions for workers
Minimization in material handling
Minimization in damage & spoilage
Minimization of congestion of material, machinery, workers
Flexibility to adapt to changing production conditions

Objectives of an ideal layout
Minimization of material handling
Elimination of bottle necks
High material turn over
Effective utilization of cubic space
Effective utilization of man power resources
Elimination of physical efforts required operative workers

Factor affecting
Type of production
Production system
Scale of production
Types of machines
Types of building facilities
Availability of total floor area
Possibility of future expansion
Material Flow system
Men , Money , Machines
Men & machine static
Material moves
Minimizing flow of material
Flow pattern helps in eliminating bottlenecks
Minimizing material handling cost

Material flow system
Horizontal flow system
Vertical flow system

Horizontal flow system
I type flow
L types flow
U types flow
S type flow
O types flow
I & U combination
I & S combination
I & O combination
I & L flow
Shortest route
Must have roads on both sides
Pant area has long length & short width
Difficulty in returning empty container
Absence of rushing of outside transportation
Unsuitable for longer product lines
U type flow
One side road link will be required
Less difficulty in returning the empty containers
Possibility of rushing of outside transportation
Suitable for longer production line
Requires square floor area
S type system
Requires roads on both sides
Absence of rushing of outside transportation
Requires square floor area
Difficulty in returning empty container
Suitable for longer production line

type
One side road link will be required
Heavy rush of outside transportation
Ease in returning empty containers
Requires square floor area
Suitable for longer production line



Types
Process layout
Product layout
Combined layout
Project layout
Cellular layout
Job shop layout
Process layout
similar equipment & tasks grouped; also called functional layout; useful for low volume, high variety jobs
used when small batches of different products are created or worked on in a different operating sequence

Characteristicsof Process Layouts
Low Volume, High Variety Production with Random Routing (Spaghetti-Like Flow)
General Purpose Machines--
Machine setups are frequent and long
Work-In-Process -- High
Throughput Rates tend to be Low
Material Handling -- High
Operator Utilization -- Low?
Throughput Times (Lead Time) -- High
System is Very Flexible, produces many different types of parts: gears, shafts, pinions, housings, clamps, etc.

Process(Functional) Layout
Advantages
low capital investment,
fewer m/c;
higher space utilisation;
flexibility in equipment allocation;
workers gain expertise;
problems localised;
job variety

Disadvantages:
needs more space;
no mechanisation;
high wip;
work scheduling problems;
high set-up
inspection costs

Product Layout
Equipment placed in usage sequence; also called line layout; useful in assembly work such as cars, m/cycle
The product layout (assembly line) is used when all products undergo the same operations in the same sequence

CHARACTERISTICS
High volume production
Special purpose machines and material handling equipment
Throughput rates--high
Work-in-process--low
Setup/Run time ratio--low
System is very inflexible
Control is relatively simple


Product Layout
Advantages
Small mfg cycle;
low wip;
min material handling;
lower labour cost;
effective quality control;
easy to schedule;
easy prodn control;
low variety
Disadvantages
Change in work nature needs change in layout;
m/c utilisation may not be optimum;
m/c breakdown delays work;
work area expansion/m/c addition not possible

Project Layout
Raw material placed in fixed positions; also called fixed position layout

Advantages
Reduces movement of m/c & equipment;
Minimizes damage/cost of movement;
continuity of assigned work force

Disadvantages:
Skilled & versatile workers needed due to multiple operations;
skill combination may be difficult to obtain;
higher pay;
movement of people/material may be expensive;
equipment utilization low as they are left at location for subsequent usage instead of being moved as & where needed

Monday, March 30, 2009

The questions arises in mind :-


What we plan to do about breakdowns of machines?
what steps are we going to take to prevent the breakdowns?

The answer to the question:-

Preventive maintenance before breakdown
Maintenance after break down happens
Preventive maintenance reduces the no of breakdowns

Maintenance Management

Efficiency of the production function
Solely depends upon the functional reliability of the production facilities
Which are nothing but a package of land ,building ,plants & equipment , tools & plant services
Such as material handling , power plant , gas & steam lines, water supply , fire fighting facilities.
Subject to wear & tear

What is maintenance
Function of production management that is concerned with the day to day problem of keeping the physical plant in good operating condition
It is necessary to ensure the availability of the machines , building & services needed by the other parts of the organization for the performance

Maintenance Management
Maintenance management is concerned with the direction& organization of resources in order to control the availability & performance of the industrial plant to some specified level
Keeping machinery , equipment and plant services in proper condition

Scope of Maintenance
Machines break down
Parts wear out
Building deteriorate over a period of time
Maintenance covers two broad categories functions

Primary functions
Secondary function

Primary function
Maintenance of existing plant and equipments
Maintenance of existing plant building and grounds
Equipment inspection and lubrication
Utilities generation and distribution
Alteration to existing equipments
New installations of equipments

Secondary functions
Storekeeping
Plant protection including fire protection
Waste disposal
Salvage
Property accounting
Pollution and noise control
Importance of maintenance mgt.
Competitive edge and customer services
Quality assurance
Avoid the danger of losing market share
Cost control

Impact of poor maintenance
Reduced production capacity
Rise labour cost
Poor product & service quality
Injuries to employee
Injuries to customer
Customer satisfaction


Objectives of maintenance mgt
Minimizing the loss of productive time
Minimizing the repair time
Minimizing the loss due to production stoppages
Prolonging the life of capital asset
Keep all productive assets in good working condition
Improve quality of goods
Minimize accidents

Areas of maintenance
Civil Maintenance :
water , gas , steam , compressed air , heating etc
Also include house keeping , scarp disposal , fencing , Gardening, lawns etc.
Mechanical maintenance : transport vehicles , MH equipment , boilers etc
Electrical : generators, transformers ,motors , telephones , lighting, fans etc

Type of maintenance
Break down maintenance
Preventive maintenance
Predictive maintenance
Routine maintenance
Planned maintenance
Planning & scheduling mgt

Maintenance planning seeks answer to the following question:
What maintenance activities to be carried out?
How these activities to be carried out?
Where these activities are to be performed?
why these activities are to be performed?
When these activities are to be performed?

Maintenance planning steps
Know the equipment
Establish the priorities
Investigate the maintenance work
Develop the repair plan
Prepare the list of maintenance material
Prepare the list of specific tools
Estimate the time requirement
Provide the necessary safety devices

Scheduling maintenance work
Scheduling indicates what maintenance work has to be carried out when & also in what sequence the work to be done
Who should do the maintenance works which are already planned?
When the maintenance work has to be done?

Reasons for maintenance sch.
Utilize the maintenance crew effectively
Utilize the maintenance equipments & tools effectively
Reduce the interruption in production
Reduces abrupt breakdown

Friday, March 20, 2009

Capacity Planning

What is Capacity?

Capacity is the ability to deliver in a defined time

To have capacity a system must have some of each of the necessary transforming resources for the operation

Both input and output measures can be used:

Output measures are usual for high-volume, standardised processes, e.g.:

Automotive production line: number of cars per week
Hotel room service: number of guests served per hour
Call centre: customer calls per hour

Input measures are usual for low-volume, flexible processes and for many service operations , e.g.

Hospital: beds available
Law firm: hours
Utilisation is also a useful capacity measure, it is defined as:
average output rate/maximum capacity x 100%


Capacity is the maximum output rate of a production or service facility and capacity planning is the process of establishing the output rate that may be needed at a facility

Capacity is the upper limit or ceiling on the load that an operating unit can handle.
The basic questions in capacity handling are:

What kind of capacity is needed?

How much is needed?

When is it needed?

In general, production capacity is the maximum production rate of an organization.
Capacity can be difficult to quantify due to …

Day-to-day uncertainties such as employee absences, equipment breakdowns, and material-delivery delays

Products and services differ in production rates (so product mix is a factor)

Different interpretations of maximum capacity


The Federal Reserve Board defines sustainable practical capacity as the greatest level of output that a plant can maintain …

within the framework of a realistic work schedule

taking account of normal downtime

assuming sufficient availability of inputs to operate the machinery and equipment in place


Factors Affecting Capacity Planning

Product & Services factors: Type of product/services to be provided
Process: The manufacturing process Availability of Facilities: State of technology & communications
Human factors: Skill & quality of workers
Supply factor: Timely & assured supply of inputs
External factors: Investors & government policies

Importance of Capacity Decisions

Impacts ability to meet future demands
Affects operating costs
Major determinant of initial costs
Involves long-term commitment
Affects competitiveness
Affects ease of management
Globalization adds complexity
Impacts long range planning

Types of Capacity

Design capacity
maximum output rate or service capacity an operation, process, or facility is designed for
Effective capacity
Design capacity minus allowances such as personal time, maintenance, and scrap
Actual output
rate of output actually achieved--cannot exceed effective capacity.


Efficiency and Utilization
Efficiency/Utilization Example
Actual output = 36 units/day
Efficiency = = 90%
Effective capacity 40 units/ day


Utilization = Actual output = 36 units/day
= 72% Design capacity 50 units/day

Determinants of Effective Capacity

Facilities
Product and service factors
Process factors
Human factors
Operational factors
Supply chain factors
External factors

Measurements of Capacity

Output Rate Capacity

For a facility having a single product or a few homogeneous products, the unit of measure is straightforward (barrels of beer per month)
For a facility having a diverse mix of products, an aggregate unit of capacity must be established using a common unit of output (sales dollars per week)
Measurements of Capacity

Input Rate Capacity

Commonly used for service operations where output measures are particularly difficult
Hospitals use available beds per month
Airlines use available seat-miles per month
Movie theatres use available seats per month

Capacity Utilization Percentage
Relates actual output to output capacity
Example: Actual automobiles produced in a quarter divided by the quarterly automobile production capacity

Relates actual input used to input capacity
Example: Actual accountant hours used in a month divided by the monthly account-hours available

Capacity Cushion
an additional amount of capacity added onto the expected demand to allow for:
greater than expected demand

demand during peak demand seasons
lower production costs
product and volume flexibility
improved quality of products and services

Forecasting Capacity Demand

Consider the life of the input (e.g. facility is 10-30 yr)
Understand product life cycle as it impacts capacity
Anticipate technological developments
Anticipate competitors’ actions
Forecast the firm’s demand
Other Considerations
Resource availability
Accuracy of the long-range forecast
Capacity cushion
Changes in competitive environment

Expansion of Long-Term Capacity

Subcontract with other companies
Acquire other companies, facilities, or resources
Develop sites, construct buildings, buy equipment
Expand, update, or modify existing facilities
Reactivate standby facilities

Reduction of Long-Term Capacity

Sell off existing resources, lay off employees
Mothball facilities, transfer employees
Develop and phase in new products/services

Key Decisions of Capacity Planning

Amount of capacity needed
Timing of changes
Need to maintain balance
Extent of flexibility of facilities

Steps for Capacity Planning

Estimate future capacity requirements
Evaluate existing capacity
Identify alternatives
Conduct financial analysis
Assess key qualitative issues
Select one alternative
Implement alternative chosen
Monitor results

Make or Buy

Available capacity
Expertise
Quality considerations
Nature of demand
Cost
Risk

Developing Capacity Alternatives

Design flexibility into systems
Take stage of life cycle into account
Take a “big picture” approach to capacity changes
Prepare to deal with capacity “chunks”
Attempt to smooth out capacity requirements
Identify the optimal operating level


Economies of scale
If the output rate is less than the optimal level, increasing output rate results in decreasing average unit costs

Diseconomies of scale
If the output rate is more than the optimal level, increasing the output rate results in increasing average unit costs

Planning Service Capacity

Need to be near customers
Capacity and location are closely tied
Inability to store services
Capacity must be matched with timing of demand
Degree of volatility of demand
Peak demand periods

Assumptions of Cost-Volume Analysis

One product is involved
Everything produced can be sold
Variable cost per unit is the same regardless of volume
Fixed costs do not change with volume
Revenue per unit constant with volume
Revenue per unit exceeds variable cost per unit

Financial Analysis

Cash Flow - the difference between cash received from sales and other sources, and cash outflow for labor, material, overhead, and taxes.

Present Value
- the sum, in current value, of all future cash flows of an investment proposal.

Factors which favors over capacity

Where there is an economic capacity size below which process is uneconomic
Building capacity is not so costly
Buying outside is not feasible
Lead time to add capacity is long
Lost sales are viewed very negatively by trading cycles

Factors which favors addition of capacity on conservative basis

Alternative capacity planning are easily available
Build up cost of capacity is low
Lead time to build new capacity is short
Lost of sales have no disastrous

Problems in capacity planning

There is no standard terminology

Every vendor has a different definition of capacity management, capacity planning, sizing, tuning, and so on.
Some vendors use the term capacity management to include both capacity planning and tuning. Others use it to denote tuning only.

There is no standard definition of capacity
One definition is in terms of maximum throughput.
Jobs per second, transactions per second (TPS), Instructions per second (MIPS) or bits per second.
Another definition: Maximum number of users that the system can support while meeting a specified performance objective.
Capacity planning is expressed in workload units.
Users, sessions, tasks, activities, programs, jobs, accounts, projects and so on.

There are number different capacities for the same system
Nominal capacity, usable capacity, and knee capacity
Other terms: practical capacity (usable capacity) and theoretical capacity (nominal capacity)

There is no standard workload unit.
In case of users or sessions it is difficult to characterize the workload that varies from one environment to another environment.
So workload independent measures such as MIPS are still popular for forecasting.

Forecasting future applications is difficult
Most of the forecasting is based on the assumption that the future trend will be similar to the past.
This assumption is violated if new technology suddenly emerges.

There is no uniformity among systems from different vendors.
The same workload takes different amounts of resources on different systems.
This requires developing a vendor independent benchmark and running it on different systems.

Model inputs cannot always be measured
Simulation and analytical models are used to predict the performance under different alternatives.
Sometimes the inputs required for the model are not accurately measurable.
Think time is commonly used in analytical models, but it is impossible to measure think time.

Validating model projections is difficult.
There are two types of model model validations: baseline validation and projection validation.

Baseline validation
requires that using the current workload and configuration in the model and verifying that the model output matches the observed system performance.

Projection validation
, requires changing the workload and configuration and verifying that the model output matches the changed real system performance. are rarely performed so the model for capacity planning is suspect.

Distributed environments are too complex to model

Initial computer systems consisted of only a few components.
Justifying the cost of each component was simple.
With distributed environments of today the system consists of a large number of semi autonomous clients, servers and network links, and I/O devices.
Workstation usage is very different from others and interactions are rather complex.
It is difficult to justify the cost of each component.

Performance is only a small part of the capacity planning problem.
The key issue in capacity planning is cost
Cost of the equipment, software, installation, maintenance, personnel, floor space, power, and climate control (cooling, humidity control).
Performance modeling helps only in sizing the equipment.
As the cost of computer hardware is declining, the other costs have become a major consideration in cap city planning.

Capacity planning is an important problem faced by computer installation manager

Number of capacity planning tools are available in the market.
Include workload analyzers that understand accounting logs
Some also have built-in monitors

Tuesday, March 17, 2009

Plant Layout

Definition & Objectives

Planning the optimum arrangement of facilities, personnel, equipment, storage space, material handling equipment and all supporting services, along with the design of the best structure to contain all these facilities

Economic handling of all material; better supervision; faster production; better product quality; flexible plant & workspace design for expansion; Improved work conditions; unidirectional workflow

Activities Classification

Office area

Plant area

Production department

Services department
Technical services
Personal services

Technical services
Receiving department
Store room
Stock room
Tool room
Inspection department
Power house
Material handling
Shipping department

Personal services
Parking area
Timekeeper office
Canteen & lunch room
Recreation room
toilets

THE NEED FOR GOOD FACILITIES PLANNING

1. Plant facilities influence operating costs and profits.
2. Planning allows facilities and its operations (ISO 14001, etc.) to comply with laws and/or regulations.
3. Facilities are fixed investments involving high capital-cost expenditures.
4. Facilities are inflexible and long term commitments.
5. The planning, design and construction of facilities require long lead times.
6. Good planning helps to avoid disruptions in production and shipping or delivery.

Ideal plant layout

Acc to F. G. Moore
“A Good plant layout is one which allows material rapidly & directly for processing . This reduces transport handling, clerical and other costs down per unit , space requirement are minimised and it reduces idle machine and idle man time”

Advantages

Better working conditions for workers
Minimization in material handling
Minimization in damage & spoilage
Minimization of congestion of material, machinery, workers
Flexibility to adapt to changing production conditions

Objectives of an ideal layout
Minimization of material handling
Elimination of bottle necks
High material turn over
Effective utilization of cubic space
Effective utilization of man power resources
Elimination of physical efforts required operative workers

Factor affecting
Type of production
Production system
Scale of production
Types of machines
Types of building facilities
Availability of total floor area
Possibility of future expansion

Material Flow system
Men , Money , Machines
Men & machine static
Material moves
Minimizing flow of material
Flow pattern helps in eliminating bottlenecks
Minimizing material handling cost

Material flow system
Horizontal flow system
Vertical flow system

Horizontal flow system
I type flow
L types flow
U types flow
S type flow
O types flow
I & U combination
I & S combination
I & O combination

I & L flow
Shortest route
Must have roads on both sides
Pant area has long length & short width
Difficulty in returning empty container
Absence of rushing of outside transportation
Unsuitable for longer product lines

U type flow
One side road link will be required
Less difficulty in returning the empty containers
Possibility of rushing of outside transportation
Suitable for longer production line
Requires square floor area

S type system
Requires roads on both sides
Absence of rushing of outside transportation
Requires square floor area
Difficulty in returning empty container
Suitable for longer production line

O type
One side road link will be required
Heavy rush of outside transportation
Ease in returning empty containers
Requires square floor area
Suitable for longer production line

Types
Process layout
Product layout
Combined layout
Project layout
Cellular layout
Job shop layout

Process layout
similar equipment & tasks grouped; also called functional layout; useful for low volume, high variety jobs
used when small batches of different products are created or worked on in a different operating sequence

Characteristicsof Process Layouts
Low Volume, High Variety Production with Random Routing (Spaghetti-Like Flow)
General Purpose Machines--
Machine setups are frequent and long
Work-In-Process -- High
Throughput Rates tend to be Low
Material Handling -- High
Operator Utilization -- Low?
Throughput Times (Lead Time) -- High
System is Very Flexible, produces many different types of parts: gears, shafts, pinions, housings, clamps, etc.

Process(Functional) Layout
Advantages
low capital investment,
fewer m/c;
higher space utilisation;
flexibility in equipment allocation;
workers gain expertise;
problems localised;
job variety

Disadvantages:
needs more space;
no mechanisation;
high wip;
work scheduling problems;
high set-up
inspection costs

Product Layout
Equipment placed in usage sequence; also called line layout; useful in assembly work such as cars, m/cycle
The product layout (assembly line) is used when all products undergo the same operations in the same sequence

CHARACTERISTICS
High volume production
Special purpose machines and material handling equipment
Throughput rates--high
Work-in-process--low
Setup/Run time ratio--low
System is very inflexible
Control is relatively simple

Product Layout

Advantages
Small mfg cycle;
low wip;
min material handling;
lower labour cost;
effective quality control;
easy to schedule;
easy prodn control;
low variety

Disadvantages
Change in work nature needs change in layout;
m/c utilisation may not be optimum;
m/c breakdown delays work;
work area expansion/m/c addition not possible

Project Layout
Raw material placed in fixed positions; also called fixed position layout

Advantages
Reduces movement of m/c & equipment;
Minimizes damage/cost of movement;
continuity of assigned work force

Disadvantages:
Skilled & versatile workers needed due to multiple operations;
skill combination may be difficult to obtain;
higher pay;
nmovement of people/material may be expensive;
equipment utilization low as they are left at location for subsequent usage instead of being moved as & where needed