production management- types of process
DESCRIPTION
ptu- mba - production and operations managementTRANSCRIPT
CHAPTER
Process Selection and Process Selection and Methods
TYPES OF PROCESS
Conversion processes : converts input into value added outputs outputs
E.g. : iron ore is converted into steel
•Fabrication Processes : change input into a specific form e.g. sheet metal is turned into the car door etc
Assembly processes : putting things together . E.g. fixing a pilfer cap on a liquid medicine bottle or fixing door to body of car .
EFFICIENCY
Any production method relies on efficiency – this can be viewed in different ways:
Productivity – a measurement of output per unit of the factor used (labour, capital or land)
Total OutputTotal Output
Productivity = -------------------
Units of Factor
Technical Efficiency – output produced using the fewest possible inputs
Productive Efficiency – output produced at the lowest possible cost
PRODUCTION METHODS
Agriculture tends to be very land intensive –efficiency could efficiency could be measured in terms of output per acre/hectare
PRODUCTION METHODS
As technology and analysis of production methodology has improved, methods have changed have changed dramatically –what used to be labour intensive production methods are now capital intensive
PRODUCTION METHODS
The choice of production method and the factor inputs depends on such things as:
• the nature of the product
• factor costs
• the scale of production
PRODUCTION DECISIONS
Market size and Segment
Which method? Type of ProductComplexity of design
Factor Costs –Land, Labour and
Capital
TYPES OF OPERATIONS
INCREASED VOLUME
Project/Job Shop
Unit or Batch Mass/
Assembly
Continuous
PROCESS DESIGN
� Project Processes (Fixed Position)
� Intermittent Flow Processes (Batch Shops)
� Continuous Flow Processes (Flow Shops)
� Processing Industries (Continuous)
JOB SHOP (FIXED POSITION)
� People and material move
� Have limited duration
� Small scale
� Examples
� Housing� Housing
� Ship building
� Dam
� Appliance Repair
INTERMITTENT FLOW PROCESSES
(BATCH SHOPS)
�No pattern exists between process of different products
�Appropriate to service organizations
�Moderate volume
Example:�Example:� Machine Shops
� Auto Repair Shops
� Commercial Bakery
� Classroom Lecture
CONTINUOUS FLOW PROCESSES
(FLOW SHOPS)
� Sequences are the same (Standard Routes)
� High volumes of standardized goods or services
� Examples:
� Assembly Lines
� Car Wash� Car Wash
PROCESSING INDUSTRIES
(CONTINUOUS FLOW)
� One primary input (gas, wheat, etc) is converted to multiple outputs
� Very high volumes of non-discrete goods
� Example:
� Petroleum� Petroleum
� Chemicals
� Food Industries
PROCESS CHARACTERISTICS
Characteristics Project Intermittent Continuous
PRODUCTPRODUCT
Order Type Single Unit BatchContinuous or large batch
Flow of Product None Jumbled Sequence
Product Variety Very High High Low
Market type Unique Custom Mass
Volume Single Unit Medium High
PROCESS CHARACTERISTICS
Characteristics Project Intermittent Continuous
CAPITAL
Inventory Medium High LowInventory Medium High Low
EquipmentGeneral
Purpose
General
Purpose
Special
Purpose
LABOR
Skills High High Low
Task Type Non-routine Non-routine Repetitive
PROCESS CHARACTERISTICS
Characteristics Project Intermittent Continuous
CONTROLCONTROL
Production Difficult Difficult Easy
Quality Difficult Difficult Easy
Inventory Difficult Difficult Easy
EQUIPMENTGeneral
Purpose
General
Purpose
Special
Purpose
AUTOMATION
� Automation: Machinery that has sensing and control
devices that enables it to operate
� Fixed automation
� Programmable automation
• Computer-aided design and manufacturing systems (CAD/CAM)
• Numerically controlled (NC) machines
AUTOMATION
• Numerically controlled (NC) machines
• Robot
• Manufacturing cell
• Flexible manufacturing systems(FMS)
• Computer-integrated manufacturing (CIM)
FUNCTIONAL AREAS BEING
LINKED TO MANAGE THE FLOW OF
INFORMATION
� Design
� Handling of Materials
Storage and Retrieval of Information� Storage and Retrieval of Information
� Control of Machine Tools
DESIGN
�CAD� No longer limited to the top, side and front views
� Can observe the rotation of the part about any axis on the
screen
� Generally, improves productivity in the drafting room by a
factor of 3 or morefactor of 3 or more
� At GM, the redesign of a single auto model requires 14 months
instead of 24 months
� The time needed to design custom values reduced from six
months to one
HANDLING OF MATERIALS
� Data processing technology can be applied to the
control of 3 general kids of machines in the
factory:
� Machines that store, retrieve, or transport materials
� Machines that process the materials� Machines that process the materials
� Robots
HANDLING OF MATERIALS
� Automatic storage and retrieval systems transfer
pallets of material into or out of storage rack up
to 100 feet high
� Mini Loaders
� Hold drawers of small parts� Hold drawers of small parts
� Automatic Warehouse
� Automatic shuttle takes the place of the fork-lift truck and
its human operations
STORAGE AND RETRIEVAL
OF INFORMATION
�GT
� The formation of part families based on design
or manufacturing similarities (or both)
� Classification of parts speed up the design of
similar parts in the companysimilar parts in the company
� Only 20% of the parts actually need new
design. 40% could be built from an existing
design and the other 40% could be created by
modifying an existing design.
� Automatic guided vehicle
CONTROL OF MACHINE TOOLS
� NC
� Machine tools run by programs
� DNC
� Direct numerically controlled machine tools
� Several computerized, NC machine tools are linked � Several computerized, NC machine tools are linked
by a hierarchy of computers
CONTROL OF MACHINE TOOLS
�FMS
�Flexible Manufacturing System
� It consists of an integrated collection of:
� Automated Production Processes� Automated Production Processes
�NC
�Robots
� A material transport system
�An automated transfer line
�Robots