Industrial Technologies

INDUSTRIAL

TECHNOLOGIES

PROF. MARCO MACCHI A.A 2016/2017 1

INTRODUCTION TO PRODUCTION SYSTEMS

First of all, it is necessary to define clearly the meaning of:

= production is a process, a list of scheduled activities that are required to

PRODUCTION (process)

produce goods or services delivered to the market by a company. The action of creating something,

realizing goods in any different way like primary production (chemical, cement industries) or

assembling components. It is a sequence of activities to transform the material in a finished product.

The activities’ sequence can be represented by ASME diagram.

a subsystem of the company. It uses resources as inputs – raw materials, semi-

PRODUCTION SYSTEM =

finished goods, energy, information, knowledge, … - to provide products and services in order to satisfy

the customer needs and the objectives established by the company’s strategy. The inputs that must be

organised in an effective and efficient way to generate outputs throughout several transformations.

Finished goods will be sold to generate profit. The output may be a physical good or a service.

physical plant, industries, laboratories, real spaces in which the production

PRODUCTION PLANT =

system is established. The physical space in which machines are collocated. This space should be

accurately designed to optimize the WIP flow along the transformations needed by the process. This

will be one of the purpose of the course: becoming able to create an efficient scheme and plant of a

production system.

Factors represent inputs of the process (material acquisition, data retrieval); production process is the

phase in which transformation take place, the phase for creating; product/services is the final part of

the process concerning the sale of the goods and the generation of customer satisfaction (distribution).

A production system is a set of assets that implements, through an industrial technology, the

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production process.

Logistic is the science that comprehend all these three activities while production refers only to that

phases that are normally held inside the company (especially for manufacturing companies that dislike

to entrust somebody else to produce finished goods because quality of finished goods is often the main

competitive gap between competitors and no company would like to advantage the others with

phenomena such as spilling over) or delivered in outsourcing but represent that part of logistic in which

things are created.

The image below shows how production may be represented at the intersection of two processes. The

creation of a new physical good, for instance, requires first of all a deep analysis because

market

managers must research and satisfy customers’ tastes with new ideas or new products. So before launch

a new item it is necessary to discover or image how market can react to this new comer. It’s required to

pay particularly attention on cash flow analysis evaluating this new possible investment with long term

objectives measurement in order to take care of investments cost and estimates future incomes and

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revenues. If the market analysis response is positive,

designer and engineers should start thinking about the

new product, its physical appearance and how it should

work. Than it’s also necessary to create an efficient

and obviously a functional

production process

production plant too.

Meanwhile, before starting to sell, logistic operators

should have begun to contact and select best supplier for

raw materials and have created a valid distribution

network to reach all the customers according to the

company objectives.

DESCRIBING PRODUCTION PROCESSES – ASME DIAGRAM

Production processes are multi-stage processes: it means that a sequence of operations are required to

realize the process that allows to obtain a product from raw materials/components (e.g. a rotating shaft

from a steel bar though various machining operations; a plastic bottle from a series of chemical or

physical transformations; a car from car body, engines and other parts). The sequence of such

operations is described in a representing the technology cycle. To do so American

process diagram

society of Manufacturing Engineering (ASME) has created a global language made of symbols.

The control step usually is at the end an in this phase the result obtained is compared to what has been

planned in order to generate a measure of performance and understand how the company has work

efficiently. This is the main reasons for which planning is so precious, because it helps managers to

discover non efficiencies.

There are different types of production flows:

Synthetic: it starts from at least two components that

• converge in a unique process; e.g. the assembly phase;

Analytic: it is the case of refineries, starting from crude oil we

• can obtain different products according to different

processes;

Combined: comprehend both synthetic and analytic

• processes.

TECHNICAL DRAWINGS Represent the relevant features of the final product. It is from an

engineering point of view.

LIST OF PARTS – BILL OF MATERIALS

It is from a view. There is a graphical representation

managerial point of

that shows how the different parts are assembled in the final product. Two

kind of information are needed: kind of components and number for each

component (it is possible to have the bill of material also in a table form). 3

CYCLE TIMES/PRODUCTION PROGRAMS

sheet: the final output is the total amount of time

Cycle time

for each operation; it works as an input for the design of the

process. The important parameters for the specific type of

the process are technological parameters: cutting speed and

feed rate. We have to translate technological parameters into

time requirements that work as an input for the process

design phase.

The is the time we need in order to

production capacity

produce that specific element on that specific machine to

satisfy demand.

The cycle time gives the order and the time per each single

transformation of the process so that we can theoretically understand how the entire

process is structured, the flow of transformation, machines and resources involved

and how does the production process last. Theoretically because we are considering

that everything will proceed in the right way, and in times scheduled but practical

experience teaches that there may be several issues like breakdowns of machines for

instance.

The usually is given to the operator together with the

production program

instructions: production program/work order.

FLOW SHEET OF A PRODUCTION PLANT

The flow sheet is helpful to get an immediately visual

understanding of the hole process. It’s not a standard language but

it is quite common, used to have an overall look of what is

happening. It’s often used by energetic engineers to explain how

gas or liquid work and circulate in rotary engines: different phases

are linked by an arrow. Through the flow sheet it is possible to

visualize both vertical and horizontal flows; it is a graphical

representation of the production system, through a map that resembles the real equipment (possible

also with symbolic representation).

LAYOUT OF A PRODUCTION PLANT

The plant layout is a schematic layout (approximated representation of each area) or

a detailed layout (we know with precision where the resources are located – detail of

the different resources in each department).

It is a map, usually a virtual and visual description of the physical places where

activities take place. It is really important for designing and eventually remodelling

plants.

TYPE OF PRODUCTION TECHONOLOGIES

A production system is an arrangement of resources necessary to sustain the process (e.g. beer brewery:

industrial process, only in the last phases you see the discrete phase). The technologies than can be used

are of different kinds.

TYPES OF PRODUCTION SYSTEM

The classification of production systems is based on:

the production strategy

• the production process, volume and demand

• the configuration of the production system

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Wortmann Classification

Companies are put in different classes according to their way of reacting to external stimulus. I mean

customers make orders and industries may be classified on the way they react to these orders. Company

operates between suppliers and customers, they need to be efficient in the way they collaborate with

suppliers and in the internal performances but also effective towards their clients.

According to these different behaviours enterprises are divided in five classes. Their behaviour as I

mentioned before depends on the condition of the market in which they operate. For instance, in a global

mass market like food market (pasta) customers expected to find products immediately on supermarket

shelves without ordering them. This kind of solutions forces industries to fill shelves before selling any

goods basing production and distribution only on accurate

forecast. – MTS (made to stock – production)

On the opposite we can find the ETO system (Engineer to

order – Ferrari, Fincantieri). In this case companies wait

for the orders and then begin to develop a new plan

according to the specifics of the client. We can guess

volumes of production are lower then those in MTO

system but of course involving more phases of production

and usually being big projects, those processes will be

much profitable.

In the middle there are other possible configuration that

companies usually adopt managing the trade off between

efficiency and effectiveness.

Abel Classification

There are 3 different dimension to classify industries:

1) demand: how the company reacts to the market and replies the orders; how it answers to the

market and works inside.

2) process: how the product is realized; two are the

main processes:

a. process industries/primary industries: they

produce large volumes of raw materials or

goods like oil or cement in a continuing way;

b. manufacturing plant: they can produce

components for other companies or processes

or they can assembly them to realize a

finished good to sell to customers.

3) volume: how many goods are realized per time. A single item, batch production of different

items or continuous production. 5

PRODUCTION SYSTEM KPIs AND COSTS

Performance measures and costs are both relevant (some costs are fixed and some others are not).

HOW PRODUCTION SYSTEMS WORK

A production system is group of different resources that are ordered and scheduled in a plant.

Implementing a production process, in order to do the different activities, resources are used; resources,

moreover, can be at different states.

Machine

A production machine could be in different status, working or blocked (idle) because of several reasons:

- working - under maintenance/repair (corrective)

- in setup/change over - …

- waiting (idle state) for different reasons

(waiting for pieces, for operators, …)

For example, we are preparing, arranging resources (raw material, WIP, operators) to realize that kind

of production activity, resources like tools needed by that specific process. All these operations which

prepare the machine to work, I mean cleaning the machine and setting the resources needed are called

setup. Machine may also be blocked due to their monthly maintenance or let me say periodic reparation

in order to avoid any kind of drastic brokerage that may cause a huge loss of performance and deeply

impact on the firm profitability. Sometime machines do not work because they are waiting for some

resources missing like operators or raw materials: these are logistic troubles that may affect their

productivity. Obviously in the worst case they may be broken too (think of using a particular tool not

allowed to work properly on a machine: it is probable it will break and cause a damage to the machine

and to the process). It is important to know this possible status because we will design the system and

so it is remarkable of paying attention to any kind of problem that may affect its right way of working.

Operator

An operator could be involved in different operational tasks:

- working on a machine/system (e.g. manual - monitoring and supervising production

assembly station) - performing quality checks

- preparing the machine (setup), e.g. hanging - loading/unloading materials

tools, cleaning, loading materials, … - …

- doing maintenance/repairing machines

From managers’ point of view, operators represent resources and so our objective is to dimension their

job, organizing their work (for example by deciding whether they have to work during the night or

during the day if the company works 24 h/day). They can be multi and over skilled and do a large

number of activities like preparing and realizing the physical transformation of products or monitoring

and supervising the whole production process: today this role is quite common because of the deep

automation of processes. Nowadays companies’ processes are commonly rich of technologies in order

to reach high volumes of production and high performances permitting companies to reduce their price

and afford cheaper goods to customers. In this case operators become controllers they check the quality

of the processes.

Raw materials

Raw materials will be processed and will change the status in which they are.

Tools

Machine tools are computerized; CNC – computer system that control the machine’s operations. Tools

have their own status as well – working in a machine.

According to the state in which resources are we can make measures.

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We have to be clear on the way production is arranged. The company receive some orders from

work orders

customers and these become (or production orders, manufacturing orders, job orders). Job

orders are planned and scheduled in the production plan according to the importance of the order and

due to the relevance of customers and obviously due to the moment in which they were made. Then job

orders are “launched” and executed. Modifications in the production plan could happen (changes in

priority, problems, …). Work orders are moved in the production system according to the

technology/process cycle. We can immediately point out that production system must be designed

flexibility

taking in account that is the capability of being flexible. It means the capability of briefly

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change and adapt to changes and modifications that were not scheduled. Flexibility is the main

characteristic of a production system. layouts,

Production may be organised in different each of them with its own benefits and disadvantages;

flexibility is of course included in these consideration: there are particular configuration that assure

much flexibility than the others like job shop rather than transfer lines (rigid system) for example. It all

depends on what we are searching for: we have to correctly and coherently shape and design a

production system in order to fulfil our needs.

A production system is organized with different layouts and its resources are normally grouped in

departments or production shops according to different basis and purposes. The entire list of

shop floor

production resources is normally addressed as (in Japanese this is said “genba”). Obviously,

different layouts will guarantee different performances in production and it is up to companies decide

what configuration to choose. Layouts differ in terms of production volume (e.g. number of products)

reachable in the amount of time and product variety (e.g. number of different types of products).

The following histogram shows a good correspondence between volumes of production and customers’

likelihood.

Where demand is enough, it will be required a system which can produces high volumes in a continuous

way. On the other hand, when demand is scarce company should decide to produce less and organized

production in batches for example.

PERFORMANCES OF PRODUCTION SYSTEMS

Performances are a way of measuring how a system usually works. We would like to measure how a

system works in terms of quality, flexibility, rapidity and so far so for. The main operational

performances are:

- lead time (throughput time, flow time): duration of time required by the work order, from start of

production to finish [hours, minutes, seconds]

- set up time: the time it takes to setup a production equipment for processing a new work order

[hours, minutes, seconds]; we should understand which machine is the most rapid or flexible to

correctly predict our productivity

- WIP – Work in Progress: the amount of inventory that is being processed or is waiting on the shop

floor [quantity of work orders, or space occupied by the material]

- production rate (throughput, rhythm, production capacity): number of products that a production

system is able to produce in a time unit [piece/h, products/day, ...]; It is the speediness of a system

- cycle time: is the time period elapsing b/w the exit time of the precedent work-piece and the exit

of the successive work-piece from a system, it is the inverse of a production rate [time/piece].

The concept of lead time

The total lead time of a job order is the time that goes from the receipt

of the customer order and its fulfilment. In other terms the time

corresponding to all internal activities belonging to the company supply

chain to physically realize the good and then

deliver it to its acquirement. It is the time that

is necessary to perform all the activities inside the factory from the customer

order arrival to the moment in which the material is ready to be delivered. As

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we can notice there are lots of different lead times

including those such as release of production order

and acquisition of the order, inspection and final

control, storage etc. So the production time is not

entirely “productive”: production activity is

composed of several phases, for example fabrication,

setup, control etc. each of them require a certain

amount of time. We are simply splitting the

production lead time in other sub-lead times that

belongs to this one in a hierarchic way.

This is a list of production consuming-time activitie