emmu 7141-manufacturing engineering and production management-marking scheme feb 2016

7/26/2019 EMMU 7141-Manufacturing Engineering and Production Management-Marking Scheme Feb 2016

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TECHNICAL UNIVERSITY OF KENYA (TUK)

UNIVERSITY EXAMINATIONS FEBRUARY 2016

FIRST YEAR FIRST SEMESTER EXAMINATION FOR

MASTER OF TECHNOLOGY (MTech) IN MECHANICAL ENGINEERING TECHNOLOGY

EMMU 711 MANUFACTURING ENGINEERING AN! "RO!UCTION MANAGEMENT

!ATE# TIME# $ HOURS

INSTRUCTIONS TO CANDIDATES

You should have the following for this examination.

Answer book-let.

Mathematical tables/calculator.

This paper contains EIGHTquestions.

Answer an FIVE!uestions

All !uestions have equal marks

Maximum marks for each part of a question are as indicated.

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Q1. a) Explain what is forecasting and its importance in industry. ($ %&')

b) Explain the steps involved in capacity planning. ExplainEITHERthe long-term OR

the short-term capacity planning strategies. (7 %&')

c) A company intends to buy a machine having a capacity to produce 198!!! good

parts per annum. "he machine constitutes a part of the total product line. "he system

efficiency of the product line is 9!#. ($ %&')

i) $ind the system capacity%

ii) &f the time re'uired in producing each part is 1!! seconds and the machine

wor(s for !! hours per year. &f the utili*ation of the machine is +,# and

the efficiency of the machine is 8,# compute the output of the machine%iii) alculate the number of machines re'uired

d) "hree components are to be manufactured on centre lathes/

i) alculate the number of lathes re'uired to produce the components if the

plant wor(s for ,! hours per wee( four wee(s a month.

ii) alculate the number of lathes re'uired assuming the machine efficiency of

0,# and operator efficiency of 8!#.

iii) ow do you reduce the number of machines

"he following information is given/

Component Type A B C "otal 2achining "ime per 3ot 4!min +!min 5!mi

n

6etup "ime per component min 4min 5min

7atchlot 6i*e 4,! 5!! +!!

uantity :emand per 2onth !!! 5!!! 4!!!

(7 %&')

(&)"orecasting is the process of estimating a variable# such as the sale of the firm at some future date.

"orecasting is important to business firm/industr# government# and non-profit organi$ation as amethod of reducing the risk and uncertaint inherent in most managerial decisions. A firm must decide

how much of each product to produce# what price to charge# and how much to spend on advertising#

and planning for the growth of the firm.

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Modern organi$ations require short-term# medium-term and long-term forecasts# depending on the

specific application. Sh*'+,+e'% -*'ec&+ are needed for the scheduling of personnel# production

and transportation. Me./%,+e'% -*'ec&+ are needed to determine future resource requirements#

in order to purchase raw materials# hire personnel# or bu machiner and equipment. L*,+e'%

-*'ec&+ are used in strategic planning% such decisions must take account of market opportunities#

environmental factors and internal resources. ($ %&')

(3) S+e4 I5*5e. / C&4&c/+ "&/# &apacit planning is concerned with defining the long-

term and the short-term capacit needs of the organi$ation and determining how those needs will be

satisfied. &apacit planning decisions are taken based upon the consumer demand 'market( and this ismerged with the human# material and financial resources of the organi$ation. The steps involved in

capacit planning are shown in the figure below.

82 %&'9

L*,Te'% &. Sh*'+,Te'% C&4&c/+ S+'&+e/e

(/) L*,+e'% c&4&c/+ +'&+e/e#)ong-term capacit requirements are more difficult to determine

because the future demand and technolog are uncertain. "orecasting for "ive or Ten ears into thefuture is more risk and difficult. *ven sometimes compan+s toda+s products ma not be existing in

the future. )ong range capacit requirements are dependent on marketing plans# product development

and life-ccle of the product. )ong-term capacit planning is concerned with accommodating ma,orchanges that affect overall level of the output in long-term 'more than one ear(. Marketing

environmental assessment and implementing the long-term capacit plans in a sstematic manner are

the ma,or responsibilities of management.The long-term capacit strategies used are

M+/4e 4'*.c+#&ompans produce more than one product using the same facilities in

order to increase the profit. The manufacturing of multiple products will reduce the risk of

failure. aving more than one product helps the capacit planners to do a better ,ob. 0ecauseproducts are in different stages of their life-ccles# it is eas to schedule them to get maximum

capacit utili$ation.

"h&/ / C&4&c/+#1n high technolog industries where technolog developments are ver

fast# the rate of obsolescence is high. The products should be brought into the market quickl.

The time to construct the facilities will be long and there is no much time as the productsshould be introduced into the market quickl. ere the solution is phase in capacit on modular

basis. 2ome commitment is made for building funds and men towards facilities over a period of3-4 ears. This is an effective wa of capitali$ing on technological breakthrough.

"h&/ *+ c&4&c/+#The outdated manufacturing facilities cause excessive plant closures

and down time. The impact of closures is not limited to onl fixed costs of plant and machiner.Thus# the phasing out here is done with humanistic wa without affecting the communit. The

phasing out options makes alternative arrangements for men like shifting them to other ,obs

and/or to other locations# compensating the emploees# etc.

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Estimation of

Present

Alternative

Capacity Plans to

Demand

Forecasting

Environment

al Scanning

Select

the Best

Implementatio

n

Quantitative and

Economic Analysis of


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8: %&'9

(//) Sh*'+,+e'% c&4&c/+ +'&+e/e#Managers often use forecasts of product demand to estimate theshort-term workload the facilit must handle. Managers looking ahead up to 56 months# anticipate

output requirements for different products# and services. Managers then compare requirements with

existing capacit and then take decisions as to when the capacit ad,ustments are needed.

"or short term periods of up to one ear# fundamental capacit is fixed. Ma,or facilities will not be

changed. Man short term ad,ustments for increasing or decreasing capacit are possible. The

ad,ustments to be required depend upon the conversion process like whether it is capital intensive orlabour intensive or whether product can be stored as inventor.

&apital intensive processes depend on phsical facilities# plant and equipment. 2hort-term capacitcan be modified b operating these facilities more or less intensivel than normal. 1n labour intensive

processes short-term capacit can be changed b laing off or hiring people or b giving overtime to

workers. The strategies for changing capacit also depend upon how long the product can be storedas inventor.

The short-term capacit strategies are

1nventories 2tock finished goods during slack periods to meet the demand during peak

periods.

0acklogs 7uring peak periods# the willing customers are requested to wait# and their ordersare after the peak period demand.

*mploment level 'hiring and firing( ire additional emploees during peak demand period

and laoff emploees as demand decreases.

*mploee training 7evelop multi-skilled emploees through training so that the can be

rotated among different ,obs. The multi-skilling helps as an alternative to hiring emploees.

8orkforce utili$ation *mploees are made to work overtime during peak hours and work

fewer hours during slack hours 'flexible work hours(.

2ubcontracting 7uring peak periods# hire the capacit of other firms temporaril to make the

component parts or products.

9rocess design &hange ,ob content b redesigning the ,ob.

Maintenance Temporaril discontinue routine maintenance so that this time can be utili$ed

for production.

8: %&'9

(c) 'i( 2stem &apacit : 'Actual output per annum /2stem efficienc

: 5;utput per hour : 3 x =.4 x =.


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:

: : ;.46 hours

F*' c*%4*e+ B*' B'e&.*? Sche.e# 0ecause large pro,ects usuall involve a ver large number ofactivities# planners need some wa to determine exactl what will need to be done so that the can

realisticall estimate how long it will take to complete the various elements of the pro,ect and how

much it will cost. This is often accomplished b developing a ?*' 3'e&.*? +'c+'e '802(#which is a hierarchical listing of what must be done during the pro,ect. This methodolog establishes alogical framework for identifing the required activities for the pro,ect

i( The first step in developing the work breakdown structure is to identif the ma,or elements of

the pro,ect.ii( The next step is to identif the ma,or supporting activities for each of the ma,or elements.

iii( Then# each ma,or supporting activit is broken down into a list of the activities that will be

needed to accomplish it.iv( The work breakdown structure becomes the focal point for planning the pro,ect.

8 %&'9

(c) The Ne+?*' !/&'&%

Activit

1mmediate

9redecessor

7uration

in weeks

5-6 '&(5-3 '0(

5-D 'A(

6-4 '7(D- '*(

--

-

5-65-3#5-D

5D5=

5D

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4-E 'G(-E "(

E-< '(

6-46-4# D-

D-# 4-E

D

D

ES @ *arliest start%EF @ *arliest "inish%LS @ )atest start%LF @ )atest finish%

S&c LF @ EF

i( The lengths of the paths areA,E,F,H C5DCCD : 3= weeks%

C,!,G,H 5DCCDCD : 6< weeks%C,!,F,H 5DCCCD : 3= weeks% and

B,E,F,H 5=C5DCCD : 3D weeks.ii( &ritical path is# B,E,F,Hiii( The expected length of the pro,ect 'duration( 1016 $ ?ee

/5)Amount of slack time for each path

A,E,F,H $ ,3= : D weeks%

C,!,G,H 3D - 6< : weeks%

C,!,F,H $ , 3= : D weeks% and

B,E,F,H $ @ 3D : =.

v) "he float for each activity is as shown on the table below.

Ac+/5/+ !'&+/* ES EF LS LF S&c

A

B

C

!

E

F

G

H

D1

D2

5=5D

5D

D

D

==

=

==

5D

5=

6D6=

3=

5=6=

5=5D

6=

6D

3=6D

3D

5=6=

D

=D

5rder.

5) I5e+*' T'*5e' R&+/*#

Thee &'e c&c&+e. +* %//%/e +he /5e+*' 3 +he e *- +he -**?/ -*'%& , 1nventor

Turnover Fatio : &ost of goods consumed/sold during the period/Average inventor held during the

period. The ratio indicates how quickl the inventor is used for production. igher the ratio# shorter

will be the duration of inventor at the factor. 1t is the index of efficienc of material management.

"e'4e+& /5e+*' c*+'* +e% , 1n a large b essential to have information about continuous

availabilit of different tpes of materials and stores purchased# issued and their balance in hand. The

perpetual inventor control sstem enables the manufacturer to know about the availabilit of these

materials and stores without undergoing the cumbersome process of phsical stock taking.

5/) ABC &&/#

1n order to exercise effective control over materials# A.0.&. 'Alwas 0etter &ontrol( method is of

immense use. ?nder this method materials are classified into three categories in accordance with their

respective values. Group PA constitutes costl items which ma be onl 5= to 6=@ of the total items

but account for about 4=@ of the total value of the stores. A greater degree of control is exercised to

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preserve these items. Group P0 consists of items which constitutes 6= to 3=@ of the store items and

represent about 3=@ of the total value of stores. A reasonable degree of care ma be taken in order to

control these items. 1n the last categor i.e. group P! about E= to !( is the order quantit that minimi$es total holding and orderingcosts for the ear. *ven if all the assumptions dont hold exactl# the *>! gives us a good indication of

whether or not current order quantities are reasonable.

C&c&+/*#

)et# : purchase unit price : L*2 4==/:% : *conomic >rder !uantit '*>!( : ! '>rderquantit(% : annual demand quantit : ;=== units% : fixed cost per order# setup cost : L*2 54==/:%

: annual holding cost per unit : L*2 3==/:

i( *>! : !Q : 2DK/h : 2x 9000x 1500/300 : 3== spares

ii( To : Bumber of orders per ear : 7/*>! : ;===/3== : 3= orders

iii( )ength of order ccle : *>!/To : 3==/3= : 5= dasiv( Total cost# T& : 97 C 7L/*>! C h!Q/6 : 4==x;=== C ;===x54==/3== C 3==x3==/6

: D#4==#=== C D4#=== C D4#===

: L*2 D#4;=#===/:

1f the order quantit is# sa 34= units 'i.e.# more than *>!( T& : L*2 D#4;5#=E5.D3#

and 1f the order quantit is# sa 6!(# thus showing that

the *>! is alwas in the best order for the workshop 8$ %&'9Q.a) 6tate the importance of the techni'ues and tools used in =roduct :esign and :evelopment.

"hese techni'ues and tools are classified into two broad groups/ Te*ni+,e& !n- Too& /o$ De&i0nImp$ovement !n- Comp,t!tion! Te*ni+,e& !n- Too&. 3ist all of them under their respective

classification. 86 %&'9;b) 3ist all the steps necessary for product development and discuss any three. 8: %&'9;c) ?hat is the difference between value analysis and value engineering 8$ %&'9;d) ?hat is difference between creative idea and innovation 8$ %&'9

;e) ow are ergonomic considerations useful in product design 8$ %&'9

&) Tech/;e &. +** e. / 4'*.c+ .e/ &. .e5e*4%e+

9roduct design contributes greatl to the improvement of competitiveness# because it permits reductionof costs# increase of qualit# and often# shortening of the time necessar to get the product on the

market. The product# in turn# generall satisfies customers necessities and demands. The techniques

and tools that are currentl in use in 9roduct 7esign and 7evelopment can be classified into two broad

groups "echni'ues and "ools for :esign &mprovement% and omputational "echni'ues and "ools.82 %&'9

1 Tech/;e &. T** -*' !e/ I%4'*5e%e+

These provide the compan with analtical techniques and tools designed to anal$e the productconcept in the context of its restrictions. Main techniques of this group are i) oncurrent Engineering%

ii) uality $unction :eployment ;$:)% iii) :esign for ;:f)% iv) $ailure 2ode and Effects Analysis

;$2EA) 82 %&'9

2 C*%4+&+/*& Tech/;e &. T**

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These are techniques that support design integration through shared product and process models# and

databases. The advantages of using effectivel &omputational Techniques and Tools are to allowdifferent teams to share information and to manage all data required to proceed on the process. Main

techniques of this group are i) Aided ;Ax) 6ystems% ii) Engineering=roduct 7ased :ata

2anagement ;E= 7:2)% iii) Bnowledge 7ased Engineering ;B7E)% iv) $inite Element Analysis;$EA)% v) @apid =rototyping ;@=) 82 %&'9

(3) The +e4 ece&' -*' 4'*.c+ .e5e*4%e+

9roduct development steps var based on the nature of the business and the management stle# butmost businesses follow seven main steps in the development process% these are 9roduct 1dea0rainstorming# *valuate the 1deas# Market *valuation# Analsis# 9rototpe and Marketing# Market

Testing and 9repare for )aunch 82 %&'9

/) "'*.c+ I.e& B'&/+*'%/

The first step is to generate an idea for the product. Ask emploees# especiall those who deal with

customers regularl# for product ideas. 2urve customers for feedback on existing products. *xamine

our industr to see whether there are areas where useful products do not exist. &reate an online surve

for our customers or social media fans to take. )ist all ideas for a new product.

//) E5&&+e +he I.e&

Make a list of product ideas and share it with the appropriate decision-makers in the compan# such as

the management team. 7iscuss the pros and cons of each idea and narrow the list to ,ust a handful of

the best ideas# based on their potential to generate revenue# as well as the time and resources ou have

to actuall create the products.

///) M&'e+ E5&&+/*

2eek feedback from customers# emploees and partners on which idea is most appealing. Ask

customers for feedback via email or phone calls. 2end an email to partners and emploees and ask

which of the products seems most useful or valuable. 8hittle the list to ,ust one or two product ideas.

/5) A&/

Anal$e the remaining product idea from a business perspective. 7etermine how much# if an#

competition exists for similar products. 7etermine the demand for the product# and estimate all costs

affiliated with the product# such as development costs and operational costs# to help determine theprofit margin.

5) "'*+*+4e &. M&'e+/

7evelop a prototpe of the product# and then share it with a handful of good customers and ke

partners. Ask them to tr it out and provide feedback. The marketing team should use that feedback to

craft marketing messages and developing marketing campaign ideas# such as email campaigns#

websites# billboards or posters. 0ase the marketing messages on the most common positive comments

or reactions from customers and partners during the prototpe evaluation.

5/) M&'e+ Te+/

Make ad,ustments to the prototpe or develop a new version# if necessar. 7evelop additional

prototpes for market testing. 7o a small product release in select areas. 2ee whether the product sells

well# and evaluate wh sales are high or low. *valuate the price and the effectiveness of the marketingmessages. A small launch helps determine what needs to be done before an official launch.

5//) "'e4&'e -*' L&ch

0egin production for the first round of the product launch. *valuate how man products to produce

based on our market testing and demand for the product. Advertise and speak to product distributors

about ordering the product# if the product will be sold in stores.

Any to to e -e&$ie- 2 1# 5 3 8$%&'9

(c) >h&+ / +he ./--e'ece 3e+?ee 5&e &&/ &. 5&e e/ee'/

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V&e A&/ can be defined as a process of sstematic review that is applied to existing product

designs in order to compare the function of the product required b a customer to meet theirrequirements at the lowest cost consistent with the specified performance and reliabilit needed.

V&e e/ee'/is the term applied to value analsis done at the .e/ &. 4'*+*+4e +&e of a

product% the potentials of saving are a more in case value analsis is done at design stage. >theradvantages are that an changes at this stage are less costl than to effect the same at a latter stage#

when the production is in full swing.

8$%&'9

(.) !/--e'ece 3e+?ee C'e&+/5/+ &. I*5&+/*

1ts eas to get confused between creativit and innovation. 1n man was the rel on each other. To

be creative# an individual# group# or compan must be able to come up with new ideas. 0ut to be

innovative# the need to act on these ideas.

C'e&+/5/+#&reativit can be a form of expression# a wa of solving problems# or the creation of new

ideas. As the name suggests# creativit is about creation. 1ts about harnessing the power of the mind to

conceive new ideas# products plans# thought experiments# tastes# sensations# or art. Anone can be

creative# and in an context.

I*5&+/*#1nnovation# on the other hand# needs stabilit and establishment. 1ts about changing a

common or long-standing process b improving it. 1ts onl b having a status quo in existence that

ou can develop it in order to innovate. 2o# while creativit and innovation share strong links# the

processes are entirel different. 1nnovation is about taking newl created ideas and developing them

into something useful and practical. 1n man was# innovation is the process of converting theor into

action. 8$%&'9

(e) E'**%/c c*/.e'&+/* e- / 4'*.c+ .e/

*rgonomics is a science focused on the stud of human fit# and decreased fatigue and discomfort

through product design. *rgonomics applied to office furniture design requires that we take intoconsideration how the products we design fit the people that are using them. At work# at school# or athome# when products fit the user# the result can be more comfort# higher productivit# and less stress.

*rgonomics can be an integral part of design# manufacturing# and use. Lnowing how the stud of

anthropometr# posture# repetitive motion# and workspace design affects the user is critical to a better

understanding of ergonomics as the relate to end-user needs.Anthropometr is the science that measures the range of bod si$es in a population. 8hen designing

products it is important to remember that people come in man si$es and shapes. Anthropometric data

varies considerabl between regional populations. "or example# 2candinavian populations tend to betaller# while Asian and 1talian populations tend to be shorter. There are common postures found in the

office environment that can be considered when designing workplace products or space% these postures

are6tanding 6itting @eaching and 2oving. 8$ %&'9

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emmu 7141-manufacturing engineering and production management-marking scheme feb 2016

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