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Fundamentals of Industrial Plants Prof. Andrea Sianesi academical year 2011/2012 . Introduction to Fundamentals of Industrial Plants. Presentation. The course of “Fundamentals of Industrial Plants” is aimed at providing students with basic knowledge on:
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Fundamentals of Industrial Plants Prof. Andrea Sianesiacademical year 2011/2012 Introduction to Fundamentals of Industrial Plants
Presentation • The course of “Fundamentals of Industrial Plants” is aimed at providing students with basic knowledge on: • The technical organization of industrial plants: production systems and of logistic infrastructures, • The more appropriate methodologies and techniques (production planning, stock management, supply chain planning) • The focus is on “Operations & Supply Chain”, with specific interest on the management aspects, i.e. on the process of taking decisions that result in operative actions
The secret of excellence New Product Development Operations & Supply Chain Design, Planning and Management
Presentation • In a firm the issues of Operations & Supply Chain are dealing with the processes of design, implementation and improvement of the company’s systems that realize products and services. New product development plan source makedeliver The reference “firm processes”
Decisions • Strategic decisions • Where localize plants • What is the production capacity that is needed • Tactical decisions • What level of stock is needed and in which warehouse keep it? • Is it necessary to use overtime work? • Operative decisions • Which orders should be fulfilled first? • Which job should be assigned to which resource?
(simplification) Position in the organization Management Board Amministration, Finance and Control IT systems R&D … Operations & Supply Chain Department Sales, Marketing… Purchasing, Quality, Production Planning, Distribution, Internal logistics, Maintenace, ecc..
The relevance of a “right” management of operations • 1950: Toyota produces on a year what Gm produces in a day • 1980: Toyota reaches an amount of sales so high to lead USA automotive industry to a crisis and to compete easily with GM, Ford, Daimler Chrysler • …realizing a product that is better on a quality level, at lower costs, and with a higher client service… • …thanks to the fact that Toyota has considered Operations Management as the central element of its firm strategy • 2010: Toyota risked to loose its leadership role due to Quality problems on a global scale
Presentation • The course is structured in such a way to: • allow students to understand the main management problems of logistic and production systems, • let student learn the main reference techniques to solve these issues with an organic approach, • provide the basic knowledge to effectively interact with the other expertise involved.
The topics • Introduction to logistic and production systems • Relevant costs for operations management • Stock management • Production and distribution planning processes • Lean manufacturing / Just In Time (J.I.T.)
Production Process Definition • A production process is the TRANSFORMATION of materials into products (economic goods), which takes place in an industrial plant... • …the TRANSFORMATION occurs thanks to energy exchanges that imply changes in the physical and chemical features of materials.
Production System Definition • The PRODUCTION SYSTEM can be considered as the production process together with all management subsystems that lead to the achievement of the transformations Production Management Information System Capitals Organisation Management Control Materials Production process Finished Products Labour Tools
Vocabulary of process analysis • Process: any part of a firm that receives inputs and converts it into outputs. • Cycle time: average time between the end of two consecutive units. • Utilization rate: temporal rate that expresses the real use of a resource with respect to the time it is theoretically available to be used.
Processes flow chart • To design the flow chart of a process means to represent -by means of a diagram- the fundamental elements of a process. • The basic elements are jobs or operations, flows of materials or of clients, decisions points and stock areas or queues. • It is the ideal methodology to start to do the analysis of a process.
Flow chart Job or operation Decision point Examples: give the entrance ticket to a customer, install the engine on a car ecc… Examples: how much change to give to a customer, what spanner to use ecc…
Fow chart Stock area or queue Flows of materials or of clients Examples: warehouses, quesues of clients at a service ecc… Examples: audience looking for his seat, mechanic moving to retrieve the right tool ecc…
Process types Monophase process Phase 1 Multiphase process Phase 1 Phase 2 Phase 3
Process types (continue…) • A buffer is an area of stock between two phases,where the outputs of one phase are put before being used in one of the downstream phases. Multiphases process with a buffer Buffer Phase 1 Phase 2
More vocabolary of process analysis • Blocking • It happens when the activities of a phase must stop because there is no place where to put the just finished unit. • If there is no space available for the worker to leave the unit, he will have to wait and he will not be able to work the next unit. • Starving • It happens when the activities of a phase must stop because there is no work to do. • If a worker is waiting at a working station and the activity to be performed is not coming, the worker will remain idle till next unit arrives.
More vocabolary of process analysis • Bottleneck • It happens when the limited capacity of a process makes pieces to accumulate or to be distributed not uniformly along the flow of a process. • If in multiphase process an employee is working too slowly , before him the pieces begin to accumulate. In this cases he is the capacity limitation that causes the bottleneck. • Pacing • It marks the fixed time intervals along the movements of items inside the process.
Productclassification (Hax & Mealmodel) Coca Cola Light type Family - model Coca Cola Light Can 0,33 l Coca Cola Light G Bottle 1 l Coca Cola Light PET 1,5 l Item - SKU Coca Cola Light Can 0,33 l 6-cans package Coca Cola Light Can 0,33 l 4-cans package Coca Cola Light Can 0,33 l 12-cans tray
Delivery and internalleadtimes (Wortmanmodel) Date oforder Forecast-basedactivities MTS ATO MTO PTO ETO Ltassembly Lt manufacturing Ltassembly Ltpurchasing Lt manufacturing Ltassembly Ltengineering Ltpurchasing Lt manufacturing Ltassembly MTS = Make To Stock ATO = Assembly To Order MTO = Make To Order PTO = Purchase To Order ETO = Engineer To Order time Due date
Production Systems Classification • The phases of new product development Design Industrialization (Process Design) Production Bill of Material designs Production cycles
Bill of Material and Production Routing • Bill of Material: hierarchical and structural representation of all the objects (sub-assemblies, components and raw materials) that compone a product Cheeseburger Bread Cooked meat Salad Mayonnaise Moulded meat Chopped meat
Structural and indentedB.o.M. A B X A H W Z B C D C X Y X W X X W X Z H Y K D X K W X
Bill of Material and Production Routing • Production Routing: list of the operations to be performed to transform a “raw” material into a “finished product”, indicating resources and time needed.
Synthesis MTS ATO MTO PTO ETO DISCRETE PRODUCTION (SINGLE PIECE – BATCH) CONTINUOUS PRODUCTION COMPLEX PRODUCT PARTS PRODUCTION – “MANUFACTURING” SIMPLE PRODUCT PROCESS PRODUCTION
Production Systems Classification Fixed (paced) Continuous Not constrained Production systems Manufacturing Assembly JobShop Fixed position Manufacturing cells Assembly shop FMS - FMC Flow Shop Transfer lines
Production Systems Classification Fixed (paced) Continuous Not constrained Production systems Manufacturing Assembly JobShop Fixed position Manufacturing cells Assembly shop FMS - FMC Flow Shop Transfer lines
Manufacturing • Technological characteristics: • Irreversible physical and morphological transformations of raw material and components; • Non fixed and discrete technological cycle, with highly diversified flexibility levels; • Not high relevance of the technological parameters of the process: relevance of the technological parameters of the product; • Usually analytical processes.
Manufacturing • Management characteristics: • Increasing relevance of management parameters (lead times, delays, appointements…); • Presence of multiple production resources (operators, machines, tools, programs, ...). • Cost structure: • Highly variable relevance of fixed capital and of labour, it depends on automation level and machine specialization. • Examples: • Mechanical working (lathe, ecc.); • Pressing (plastics, metals, ...).
Job Shop • It is a manufacturing system organized in different WORK CENTRES in which different types of machines are placed. • Work centers are built according to TECHNOLOGICAL AFFINITY
Job Shop • Flows are extremely interwoven • Labour is often the critical (limited) resource • Products pass most of the time WAITING or QUEUING • Each product has its own ROUTING (technological cycle), that defines a route through several types of machines • There are several alternative cycles (routings)
Job Shop, disadvantages • Difficult to control product flows • High Work In Progress • High throughput time • Low machines saturation • Quality level not much constant • Difficult to Manage Production • Difficult to foresee bottlenecks • High dependence of performance on mix of products to be manufactured
Job Shop, advantages • Very high flexibility • Availability of general-purpose machines and thus ability to produce a potentially infinite mix of items • Possibility to set alternative cycles (routings)
Manufacturing CELLS • Machines are arranged according to PRODUCT HOMOGENEITY (FAMILIES) • Cells are designed using GROUP TECHNOLOGY models • There are no flows among cells
Manufacturing CELLS, disadvantages • Balancing loss of workloads among cells • Difficult to gain completely autonomous cells • High implementation costs (due to lay-out review) • Difficult to manage mix turbulence
Manufacturing CELLS, advantages • Shorter Lead time • Lower Work In Progress • Customer-oriented • Multitask Labour • Setup Reduction • Better utilisation of shop floor space • Higher saturation
Stages (Stations) are arranged in a sequential line (not necessarily a ‘straight’ line) Machines are dedicated to the production of a single product or a product family Production rates are extremely high The solution is efficient but rigid Manufacturing TRANSFER LINES
Synthesis Product line width Job Shop Manufacturing cells Transfer Lines Production volume
Assembly • Technological characteristics : • Components joinining to form assemblies, modules and finished products. This joining is reversible; • Free and discrete technological cycle, with highly diversified flexibility levels; • Not high relevance of the technological parameters of the process: relevance of the technological parameters of the product; • Syntetic processes.
Assembly • Management characteristics: • High relevance of management parameters (lead times, delays, appointements…); • Cost structure: • Generally low relevance of fixed capital, anyway it varies depending on automation level and machine specialization. • Manual operations are prevailing and so labour relevance is generally high. • Examples: • Vehicles (Automobiles, motos, trucks, trains, ...); • Electronics and electrotecnics.
Fixed position assembly • suitable for assemblies of big and heavy objects (tool-machines, aircrafts...) • the object that has to be assembled keeps a fixed position, while components, tools and labour converge on the assembly-site
Fixed transfer systems • classical solution of the assembly line belt with a number of stations where one or more workers can work according to the size of the object • the stations are linked by a transportation system that after a certain time lag (“line cycle time”) transfers a sub-assembled part from a station to the following on
Transfer systems; disadvantages • the cycle time is fixed but not the length of manual operations • job sharing out • high time-to-start of new productions
Transfer systems; advantages • compared to fixed-position assembly, they allow high volume production with lower costs and space utilisation • the solution of transfer line maximises efficiency and plant rationality
Synthesis Product line width Fixed position Assembly shops or NOT CONSTRAINED transfer system Fixed transfer lines Production volume