IV. GENERALIDADES DE LA UNIDAD DE NEGOCIOS
4.3. Flujograma del Proceso
i i i . Having an on-go ing training
programme for .crews and sup ervi s ors so t hat anyone c ould do any j ob ( 3 5 )
Einbinder ( 36 ) report ed t hat a c osmet i c packaging c ompany minimi s ed the c ost of s et-ups by ensuring t hat there were suffici ent lines t o enab l e a new run t o b e s et -up before a crew bad to move t o t h e line. The firm also put gre at emphas i s on ensuring the line was s et up c orrect ly , p oint ing out t hat "Th e addit i onal t ime of the s et-up man is far outwe ighed by t he man-hours of s everal op erat ors wast ing t ime or doing unnec e s s ary wo::r:k t o
c omp ensat e f or a bad s et-up . "
In f low- line product ion invo lving the manufac:!:;ure of c omp l ex product s such as aircraft , product i on-p lanning t o ensure t hat all res ources are c o-ordinat ed is a highly c omp lex proc e s s. This c an be furt her c omp ounded by short product i on runs. \Vart erbury ( 37 ) rep ort ed t hat Lockhe ed use a highly s ophist i c at ed comput er-b as ed p lanning syst em cal led. " G enp lan " t o generat e manufacturing pro c e s s p l ans .
Measures t o deal with s hort production runs in f low-l ine product i on are aimed at r educ ing the s et-up c ost and increas ing t he rat e of le arning of op erat ors as well as r educ ing t he c omp li cat ions of t he p l anning t ask . The s e ob j ec t ives were met through :
l . Use of f lexib le non- specialis e d
machinery ;
i i. Subst itut ion of labour for c ap it a l input s t o increas e f l exib i l ity ; i i i. U s e of modu lar unit s in des ign and
product i on.
lV . U s e of photographs and other
pict orial methods to increas e the
rat e of learning.
v . U s e of t an e rec ordings t o increas e the rat e of l e arning.
vi . Se l e c t i on of a�propriat e cyc le t ime
to minim i s e the eff ect of learning.
vii. St andardisat i on of part s t o mini�is e
v11 1 . Se l e ct i on of �at erials which have
low t oo ling cost.
1x. Training staff t o improve f l exibi lity .
x . Us e o f c omput ers t o ass ist in c omp lex
product ion p lanning.
F l ow process product i on invo lves the cont inuous
or s emi- c ont inuous manufacture of dimensional p roduct s . It is the most rec ent ly dev e lop e d form of product i on.
It is hi ghly capit a l int ens ive and requires r e l at ive ly hi ghly skilled op erat ors. Examp l e s of sucb product ion inc lude the manufact�re of chemic a ls such as sulphuric aci d , c ont inuous f erment at i on proc ess to produ c e alcoho l , print ing pro c esses us ing w eb-f ed pres s es and many food product i on processes .
Wo odward ( 38 ) r ep ort e d that in t he study of 1 00
firms , c l as s ified as in Figure 2 . � ( where proc e s s
product i on c orresponds m o s t c los e ly t o f low-process product i on ) � the f o l l owing em erged :
1 . t here was more de legat ion of authority
in proc e s s than other typ e s of product ion ;
1 1. t he lengt h o f the line of c ommand ( number of leve ls o f hi erarchy) was great est in p roc ess product ion ;
iii. t he span of c ontr o l of the chief exe cut ive was great est in proc ess production , he act ed as a chairman rather than an authorit ari an f i gure ;
1v. t he prop ort i on of turnover in wages and s alaries was l east in proc ess product ion and industrial relat ions were genera l ly b etter , probab ly due t o less t ension and pres sure , smal l er working groups and
small spans of c ontrol in middle management ;
v . the rat i o of managers t o t otal p ers onnel was much gre at er in pro c e s s indust ry
( 1 : 8 proc e s s , 1 : 1 6 large batch and mas s , 1 : 23 unit
)
. Addit i onal ly managers werebett er qualif ied wit h a large
proport ion of graduat e s in l ine management.
vi. There was a great er proport i on of indirect labour t o direct labour in proc e s s product i on.
vii . There was a great er prop ort i on of c l erical and administrat ive labour to manual l abour
in proc e s s product i on.
vi i i.There was a larger numb er of ski l l ed workers1 in proc e s s and unit produc t i on t han large bat c h and mas s product i on.
Learning behavi our has b e en obs erved in f low
proc e s s product ion. Baloff and K enne l ly ( 39 ) report ed
that in a rec ent study of pro c e s s st art-ups in t he st e e l indust ry , st eady st at e productivit y was reached t hat was
1.6 t o 1 1 t imes gre at er t han the average product ivity of
t he f irst mont h of op erat i on. Hir s chmann ( 30 ) report ed
t hat over a p eriod of t en years , t h e t ime r e quired t o put a Whit ing ref inery f luid cracki ng unit on- stream
dropped t o l e s s than half the t ime initially r e quired.
The c ot t on indust ry in Brit ain was p l agu ed by a great vari ety of sp ecificat i ons and c ons equent short
run l engths according t o Robson ( 40 ) . He suggest ed t hat
ec onom i e s c ould be ac hi eved from a reduct i on of vari ety by :
i . reduc ing administrat ive and c lerical exp ens e s ;
i i. reduc ing t he amount of s t o ck holding n e c e s s ary ;
i i i. reduc ing t he t ime when machine s or
men were idle t hrough difficult i e s
i n dovet ai ling one order into another ;
lV. reduc ing the proport i on of time sp ent
in machine s ett ing as against machine running ;
1 . There was s ome prob l em in obt aining the ski l led operat ors neces sary as although they were oft en highly skilled in t hat s ituat i on , they - were not r e c ogni s e d as ski l l ed out s ide t he firm.
v . by p ermitt ing an opt imum dep loyment of lab our and more generally , of a l l t he f act ors of product ion.
In addit i on he sugge s t ed t here may b e a saving from the increas ed ski l l of management and op erat ors l eading
t o an improved f l ow of output and a reduction in faults.
In the past , gravure-print ing has been restri c t ed t o us e in largest c irculat ion in t he pub lishing f i e ld and longer runs in p ackaging due t o a great ext ent t o the cost of the gravure cylinder . However , a new
gravure cylinder product i on proc es s , r eport ed by Purdy ( 41 ) has redu c e d t he c ost of cylinder manufacture by ab out one
half. The cylinders a l s o t ake significant ly l e s s t ime
to engrave t hus mak ing it p o s s ib le to produc e short runs more economically.
The re lat i onship of various proc ess and product p aramet e rs t o run l engt h in a napt ha cracking heat er has b e en examined by Mo l (42 ). The end of a run c an b e
caus ed b y c oking o f t he cracking c o ils o r by f oul ing of the transfer line exc hanger. Mol examined t he
re lationship of f i lm eff ect and tub e-wall t emp erature , f e edst ock , out l et t emp erature , out l et pressur e , di lut i on st eam , c o i l des i gn and s i z e , burner typ e and layout , tube mat erial , and t ub e l engt h and arrangement t o run
length and was ab le t o rec omm end op erating strat egies t o improve run lengt h.
M e asures t o deal with short product ion runs in f low-pro c es s product i on must deal wit h t he high s et -up c osts and improve l e arning rat e where possib le.
Addit ionally , M o l ' s art i c l e indi c at ed a run- length f eature unique t o t hi s typ e of manufacture : the int er action of t he mat erial and t he pro c es s plant.
There is re lat ive ly litt le publ ished inf ormat i on dealing with t hi s c lass of product i on and s o , b e aring in mind t he sp ec ial natur e of t hi s product i o� m et hods t o bring about s o lut i ons t o t he short product i on run prob lem must b e ext rap o lat ed from other f orms of p roduct i on or be comp let e ly nove l.
2 . 6 SHORT RUNS IN SPRAY DRYING PLANTS
The c ommonality of many prob lems in a wide range of manufacturing has b e en discus s e d . In all s ituat i ons a
product i on manager mus t p lan and c ontrol to m e et ob j ect ive s . He must c o- ordinat e m en , machinery and materials in t he
fac e of unexp e ct ed dis t urbanc e s in order to manufacture a
s at isfact ory product.
Spray drying p lant s are different from _ the other typ e s of product ion t hat have b e en dis cus s e d . There are a number of f e atures t hat mak e t hem diff erent . T he s e inc lude :
i . The s easonal p att ern of milk flow .
Manufactur ing is dependent on the product ion of the raw mat erial whi c h occurs in a s e as onal pat t ern wit h a peak of t wice the average f low . ll . Perishab i l ity of raw mat erial .
The s hort life of t he raw mat erial due t o rapid microbio l o gi cal att ack makes st orage
impract i c ab l e and nec e s s itat e s prompt pro c es sing.
iii . A re lat ive ly small labour force.
A small numb er of p e op l e are respons ible
for t he m a j or port ion of t he pro c e s slng.
iv . Limit ed variat ion in p l ant and product.
All raw mat erial must pass through the
bas i c st eps of s ep arat i o n , evap orat i on ,
drying and p acking . To bring about variat i on
minor p l ant it ems are added in vari ous
c omb inat ions and f low r at e s and t emp eratures alt ered.
v . Limit ed p l ant running t ime.
The plant ' s running t im e is limit ed by s c a l e
bui ld up in t he evap orat or and microb i o logical growth so t hat f or practical purp o s e s , a l arge p art of it must be c le aned c omp let e ly every
24 hours.
vii . A high prop ort ion of c o st is f ixed .
The labour c o st is fixed. Plant must b e staffed t o handle thep eak flow an d because o f t he ski l l invo lved c annot readi ly b e shed and replaced. Also p l ants are oft en in are as whi ch do not have a ready lab our market. There i s a dai ly cost of st art-up , shut down and c leaning regard l e s s of vo lume of product , with t he evap orat or
c on s e quent ly running f or s everal hours without product.
Finally , t he p l ant it s e lf is an exp ensive maj or s ingle it em and p art s c annot be readi ly s hed or ac quired t o alt er c apacity.
The s e f e atures and others di s t inguish spray drying
p lant s from other t yp es of product i on. However , spray
drying p lant s also have many s im i l arit i e s with other types of producti on. The ir s ophisticat ed pro c e s s t echn o lo gy , high cap it al , and low lab our c ont ent and free-f l owing product and raw mat erial app e ar t o be a c las s i c c as e of
a f l ow-p ro c e s s industry . However , they als o have f eatures of bat c h t yp e s of product i on. There i s a l imit e d vo lume t hat can b e pro c e s s ed before c l e an ing , t here i s a dai ly st art-up and s hut-down , and t he e quipment is r e l at ive ly general p urp o s e in t hat all t��ee maj or typ e s of product , n ame ly SJVJP , WJVJP and BMP can be pro c e s s ed in the one p lant with only minor addit i ons and c ont rol alt erat i ons.
It must b e c onc luded t hat product i on in spray drying p lant s i s a hybrid pro c e s s and short produc t i on runs may
invo lve p rob l ems and draw s o lut i ons from a vari ety of typ e s of manufacturing.
From t he study of bat c h product i on it .was c onc luded t hat s et -up c o st w.as a major fact or in short runs. An
examinat i on of s et-ups in spray drying p l ant s must b e made t o det e rm ine if t his i s the case , and i f t he t ime t ak en for s et -up is a crit ical factor. If s et-ups proved t o be a probl em c ould f l exib le aut omat ion or c omp�t ers be of as s i s t anc e ? Could t he u s e of unc onvent i onal e quipment or proc e s s e s avoid such s et -up c o s t s or c ould t he Dairy Board organis e t he all ocat i on of orders diff erent ly t o