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Page 1: On the Analysis of Component Handling Technology

On the Analysis of Component Handling Technology

W. Scholz, G. Arndt (2), University of Auckland - Submitted by J. H. Percy ( 1 )

Cuuponent handling represents a high proportion of manufacturing costs i n industry. It is concerned with all functions which cause mater ia l flow a t and i n the range of manufacturing workplaces. Based on an invest igat ion of t h e component handling s i t u a t i o n i n New Zealand's manufacturing industry, the paper b r i e f ly deals with the methodology developed f o r t h i s purpose, and presents the major r e s u l t s of t h e industry invest igat ion.

Depending on individual sect ions, New Zealand's manufacturing industry can be c l a s s i f i ed as s i tua t ed on the "borderline" between a high and a low technology country, covering a wide range of technological developent . However, t he procedures and methods developed here, are equally appl icable i n any i n d u s t r i a l country, and p a r t i c u l a a i n those sectors where products and production quan t i t i e s are similar t o those ex i s t ing i n N e w Zealand, where batch production predaninates.

1.0 INTRODUCTION - d e v e l o p n t of s t r a t e g i e s t o encourage the improvement

Using an establ ished de f in i t i on /l/,"component handling" is cerned with a l l funct ions causing mater ia l flow a t the workplace, Based on these object ives , t he N.Z. invest igat ion was espec ia l ly i n the range or i tmediate v i c in i ty of manufacturing performed i n three phases: uni ts . It m u s t therefore be seen as pa r t of the overal l Phase I: Select ion, from t h e l a rge va r i e ty of &ern materials handling function, which covers the entire mater ia l component handling techniques ava i l ab le today, flow in and out of manufacturing establishments.

of t he handling function within the factory environment. con-

of those considered as appropriate For N.Z..

The importance of component handling can be seen from the fact that within a typical operat ional cycle, machining requires 20 to 251 of the manufacturing cycle time, while the tasks concerned with In t e r n of cost, another study /3/, performed i n the one-off and small batch production operations, show that 30 t o 852 of the t o t a l mnufactur ing costs are mater ia l handling costs.

These figures convincingly demonstrate t he importance o f canpo- nent handling. In earlier years t he main emphasis i n prcductivi- t y improvanents was on improving t h e machining processes itself, by using better technologies to reduce main machining time. Recently, however, R+D i n s t i t u t i o n s and industry itself have put major efforts into the improvement of component handling techniques, as witnessed for example by the rapid technological development and growth i n t h e use of i ndus t r i a l robots i n leading indus t r i a l countr ies shown i n Figure 1.

cmponent handling take an average of 60% /2/.

a

'$1

-1982 1

Growth of i ndus t r i a l robot i n s t a l l a t i o n s (Source: IPA,

Such developments w i l l become increasingly important. So, i n 1988, 50$ of t h e d i r e c t labour i n small component assembly w i l l

h e 11: Analysis of the present s t age of development of canponent handling i n N.Z. manufacturing industry.

Phase 111: Development of s t r a t e g i e s f o r improving the latter.

This paper sutnnarizes t h e main Findings of phase 2. Detai ls on the other two phases are Found i n / 5 / .

2.0 lElXlWLoGY FOR INWSTRY ANALYSIS

2.1 Select ion Of Indus t r i e s To Be Investigated

The r e l a t ive ly small manufacturing industry of a country such as New Zealand, with approximately 9000 manufacturing establ ish- ments, has more than 3M) 000 workplaces. Not a l l of these work- places are concerned with canponent handling so that the nmber of individual handling workplaces is considerably lower. In order to obtain r e s u l t s of econanic s ignif icance, those workplaces representing most of the component handling workplaces of g rea t e s t econwic importance have t o be determined first.

Because of the usual ly l imited a v a i l a b i l i t y o f data on indivi- dual handling workplaces, an appropriate approach is v i a the ana- l y s i s o f economic data of the manufacturing industry, which then allows conclusions regarding its component handling function. In t h e New Zealand invest izat ion an analvtical method was used. based on ABC-(Pareto/torenz) ana lys i s of the number of persons employed per i ndus t r i a l subgroup, cd ined with t h e three se l ec t ion c r i t e r i a roduction volume, predcminant manufacturi processes (manufactuL of d i sc re t e components only, e x c l u d i z process industry) , and indus t r i a l experience of the investiga-

be replaced by programable automation, according to one of Merchant's technology forecasts /4/. Certainly this time scale m y not relate d i r ec t ly to less indus t r i a l i s ed countries.

. muclLwv m FABRIrAlIffi. RATE MPL pNImimwpRxuos

Nevertheless it is probable tha t , because of t h e internat ional 0 p 6 R I c L L ~ WCiIIoFI Iw) EuJlRwl connection of technology developments, these developments w i l l mlC4 INUSTRW. MlIoFI PI0 apply with a time gap of sure years. m m

SRCILIrn ImIk Mlm PH) The reasons for performing t h e research reported here /5/ are EgllRMl

based on the premise, that i n general , productivity of New Zealand manufacturing industry is low /6/ and that this to a l a rne extent is due t o t h e use of ine f f i c i en t canwnent handlina t e c k q u e s . It is thus par t of a continuing e f f o r t t o upgrade manufacturing industry i n New Zealand i n pa r t i cu la r , and i n so doing, to develop methodologies and techniques which may a l s o be useful to other - developing as well as "developed" - countr ies per se /7/,/8/.

The main research object ives were as fol lo~3: - i den t i f i ca t ion of sho r t cmings i n t h e techniques used and analysis o f reasons f o r the shortcanings; - determination of appropriate component handling tech- niques, and, i f necessary, the development of these;

M sLB(IIxp *EAT Oarrr*orar' 1s MEED m -ISM

Fig. 2: Indus t r i a l subgroups selected and t h e i r cha rac t e r i s t i c econanic data

Out of 148 ex i s t ing indus t r i a l subgroups, 10 w e r e se lected f o r t h e invest igat ion. These 10 . subgroubs. shown in figure 2, represent only 6.8% of a l l i n d u s t r i a l subgroups, but, as a r e s u l t of the se l ec t ion by ABC-analysis, they represent 152 of a l l persons employed, 17.82 of a l l establishments, 15.51 of t h e value

Annals of the ClRP Vol. 32/1/1983 393

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added and manufacturing industry.

with the help of the NZ Department of S t a t i s t i c s . From each of the indus t r i a l subgroups selected the Department supplied addresses of establishments. 41 canpanies were v i s i t ed during the investigation.

15.81 of the turnover i n the whole of the New Zealand

The select ion of representat ive en te rp r i se s was performed

0 Economic conditions 0 Availability and qualification

of workforce

2.2 Scope Of Industry Investigation

10 selected indus t r i a l subgroups, show that the c l a s s i f i ca t ion i n t o indus t r i a l subgroups used by the Department of S t a t i s t i c s is not very appropriate for the needs of t h i s study. Many canpanies were d i f f i c u l t t o categorise, as they manufacture products rele- vant t o several subgroups. Information obtained f r m one company therefore a l s o yields information appertaining t o other sub- ~ p s . The degree t o which the selected canpany is representa- t i v e f o r its particular indus t r i a l subgroup is therefore only me- dim, however to the whole of the manufacturing industry it 1s high.

9

The v i s i t s , performed i n canpanies spread across all of the

OBTAINED A T EACH CO\lPAYY

NO. OF COZlPANY Fig. 3: Cuantitative learning curve f o r i ndus t r i a l v i s i t s

Figure 3 shows t he information obtained as a function of in- creasing the number of v i s i t s . Cnly those i t am a r e added which r ea l ly add new information, and a r e relevant t o canponent handling. The graph represents a typical learning curve, and shows t h a t t he number of companies may be limited without great loss of detai led or addi t ional information. The reason for the r e l a t ive ly slow start of t h e "learning curve" is t h a t the first 10 v i s i t s were preliminary s tud ie s before the general questionnaire was established. More than 90% of the total new i n f o m t i o n items discovered were obtained i n the first 18 v i s i t s (441). The later v i s i t s however helped t o iden t i fy the relevance of shortccmings i n t h e establishment of a frequency d i s t r ibu t ion , and t o confirm earlier findings.

- I

- transport systems - handl ing workplaces

2.3 Criteria And Method Of Analysis

For the evaluation of t he component handling s i tua t ion in the manufacturing industry of a country a multitude of criteria can be used. In this invest igat ion the c r i t e r i a were c l a s s i f i ed i n t o the two groups shown i n t ab le 1.

GENERAL INDUSTRY -

processes storaae systems

Social ihuman determinators

Table 1: Criteria for t he analysis of the canponent handling s i tua t ion

The first p u p covers criteria which character ise the c a n p e n t handling s i tua t ion within an industry generally, such as sa fe ty regulations or award agreements. The second group is concerned with criteria which analyse individual handling problems, such as t he application of i ndus t r i a l robots. Accordingly and i n order t o obtain canparative data, two questionnaires were developed, one of a general nature and one on workplace analysis, t o be used f o r t he individual analysis of component handling workplaces.

information, especial ly for t he industry-related criteria, was also obtained by contact with d i f f e ren t i n s t i t u t i o n s such a s industry boards, unions and government departments. The mre s i m i f i c a n t findings of t he New Zealand invest igat ion w i l l now be described, based on t ab l e 1.

Apart frm the individual caopany invest igat ions,

3.0 N.Z. FINDINGS: INDUSTRY-RELATED CRITERIA

3.1 Products And Production Sizes

Products and t h e i r production s i z e s determine t h e i r mst economic manufacturing methods. The products analysed i n the investigated companies, be they ca r s , home appliances, e lectronic or agr i cu l tu ra l equipment, are similar or even the same as those in overseas industr ies , because N.Z. customers d e m d s are similar t o those overseas, and because many of t he canpanies investigated (LIlJ) are pa r t ly overseas-owned. Products and manufacturing processes are therefore based on technical agreements, which a l s o e x i s t w i t h i n independent N.Z.

Wff WN P l i r m C T s ~ r n - m LMFKUXTIOYWAAE m w

companies.

p: 4 2 0

1 z -10 u - D I 101- imi- M O l l - 4 L B L m U€FA l L m M O B DILm

KINI PRaXCllM WUK ( INITS AR YE4 )

Fig. 4: Frequency d i s t r ibu t ion of production volrrmes

N e w Zealand production quan t i t i e s are genetally lower than those i n highly industr ia l ised overseas countries. However many products are made i n the medium- and high- volume production range. There is no clear de f in i t i on of "low", "medium" or "high" volume production. In f igure 'I, W+ng the ffequency d i s t r ibu t ion of production s i z e s of the maw products, a r b i t r a r y borders a r e used a t 100 and 10 OOO un i t s produced per year, respectively. Lou production vollrmes are mder-represented, because the ques t ioma i re only asked for the main products m u f a c t u r e d . Houever, the study is representative f o r mediurc- and high-volume production. Here more than half of the products analysed could be c l a s s i f i ed i n the high volume production range of more than 10 000 un i t s per year. Figure 4 represents the total annual production quantity of a l l product mcdels. The different product models were however manufactured on the same production un i t s m u a l l y after set up changes.

If t h e production vollrme of a product is s p l i t up i n t o the individual production volumes of its d i f f e ren t models, the d i s t r ibu t ion , depicted in figure 5, looks different. The cross-hatched area shows the desired d i s t r ibu t ion f o r increased automation, viz. few product models with high production volumes. The New Zealand d i s t r ibu t ion shows however t h a t only few products e x i s t in this area. &I the other hand the d i s t r ibu t ion illustrates that medium-volume production, with a r e l a t ive ly small number of models per product, is C ( ~ P P Q I (25 main products, or 391, consist of 10 or fewer models w i t h a maximum production volume between 101 and 10 000 units per year).

Frequency d i s t r ibu t ion of nrunber of mdels per product with t h e i r maximum production volume

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3.2 Equipment And Manufacturing Processes

It is not possible t o s t r i c t l y c l a s s i fy the indus t r i a l subgroups investigated i n t o groups of high or low technological standard of w u f a c t u r i n g . The spread from a high t o a low standard, even within one cappany, is very wide. Anything f r an microprocessor-controlled equipment to very old mnventional machinery can be found. Also i t cannot be sa id that i n general the bigger companies use more advanced technology than do the smaller ones. Because the products manufactured i n New Zealand are es sen t i a l ly the same a s overseas, manufacturing processes as well as equipment used are similar. The main difference e x i s t s i n the degree of appl icat ion of mre automated equipment. A.good example with avai lable data is the introduction of NC-machinery i n t o New Zealand /9/. Figure 6: shows the number of NC-metalworking machines in s t a l l ed per million people for selected countries. While the growth rate of NC-equipnent i n New Zealand is about equal t o m o s t o ther industr ia l ised countries, a time l a g of approximately 6-10 years ex i s t s .

Fig. 6: NC-metalworking machines f o r selected countries

. ,,. M SELF- 1-M 11-20 21-30 31110 41-9 3-Fa 61-M 71-R3 81-90 91-100 %

m m n R OF sEw-muE FWIFET

Fig. 7: Frequency d i s t r ibu t ion of self-designed equipment

Page 11

Most New Zealand c m p n i e s tend to purchase t h e i r manufacturing equipment. A s figure 7 show, 62% of the caupanies which supplied su i t ab le information have a percentage of purchased equipment 5 80%. Around a quarter of t he manufacturers however design and build a substant ia l amount of the i r equipment themselves. Also it was found t h a t t h e ava i l ab i l i t y of standard handling equipment is very limited and has therefore to be bu i l t with high cos t s t o order.

Concerning the equipment age f igure 8 shows that 58% of the production plant i n New Zealand is older than 10 years. Although this figure is ce r t a in ly high, the comparison with German industry show that the average N.Z. equipraent age i S Only s l i g h t l y higher.

3.3 Economic Conditions

The first and foremost requirement for improving a compcnent handling task is economic v i ab i l i t y . Main factors influencing economic v i a b i l i t y are plant u t i l i s a t i o n , required return on investment, labour cost , plant depreciation regulations and equipment cost .

Plant u t i l i s a t i o n can be seen as an indicat ion f o r production sizes. High plant u t i l i s a t i o n usually means high production volumes indicat ing t h a t mre econanical production methods such as e.g. flow production can be applied. Furthermore cost advantages can be achieved by the rrsually higher tax-exempted depreciation rates f o r more-shift operation.

O f the companies investigaated (see f igure 9 ) 90.24% work l-shift,12.2% of then with a second shift i n special areas, such as NC-machinery, press-shop or p l a s t i c moulding, and another 2.44% with a th i rd shift i n p l a s t i c moulding. The remaining 9.76% are divided i n t o 2.442 with an extended 1-shift operation of 1x12 hours per day, and 7.32% with 3-shift operation. The f igures c l ea r ly indicate t h a t 2- or +sh i f t operation is not copm3n in New Zealand, a fact which is very surpr is ing when working with capital-intensive plant such a s K-machinery.

l-9ilFr DOOYUI 2-siIFr >%In (M) l-%lFI (m) (3x84)

(Ld2H) UjWL WFTS IWED ER MY

Fig. 9: Distribution of shift operation

Apart fm t h i s , it was frequently found that the degree of plant u t i l i s a t i o n even within 1-shift operation yas qu i t e low. In 24% of the cmpanies v i s i t ed caruoent was made on the low degree of u t i l i s a t i c n of expensive plant. In all cases the managers claimed tha t this was due to the present (1981-82) depressed s i tua t ion of the New Zealand ewnany.

A second major parameter, return on investment required, can also be expressed by the amortisation or payback period. Because of the in t e rna t iona l connection of mnetary systems, canpanies in New Zealand and other countries would l i k e the maximum amortisation period not t o exceed 3 t o 4 years.

Since automated a l t e rna t ives cmpe te with manual solut ions in component handling , the influence of labour cost is quite s ign i f i can t . Figure 10 show a compariscn of average hourly labour cost i n selected OECD-countries. New Zealand (and Japan!) i n this canparison lies at the lower end of tbe scale. The incentives f o r automation through potent ia l saving of labour cost is therefore lover than i n most other countries. However the gap i n labour cos t between New Zealand, with its high in f l a t ion r a t e , and other "low-inflation" countr ies is closing fast. For example the average salary increases in the FRG have been 5% over the last few years, while N.Z. increases have been around 15l.mark.

Fig. 8: Age comparison of production plant New Zealand-Federal Republic of G e m y 1977(Sources: NZ Manufacturing Engineers Federation, Deutsches Ins t i tu t fuer Wirtschaftsforschung)

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*)INCLMIK, WyIII4RY WAGE KSE. L Y r W t i G E S T E 1 l l Z s = 1.8 Y

Fig. 10: Canparison average hourly labour cost i n selected OECD countr ies 1980 (Sources: OECD, I n s t i t u t e of t he G e m Econany, NZ Award agreements, own calculat ions)

Depreciation regulat ions, as well as spec ia l incent ives such as tax exemptions i n developing areas, are governmental tmls to influence technological developments because they o f f e r invest- ment incentives. These regulat ions are d i f f e ren t f r an country to country and d i f f e r of ten regional ly within a country. A comparison, based on equal po ten t i a l savings th rwgh improved s y s t e m but on t h e d i f f e ren t depreciat ion regulat ions, showed, i f calculat ing the canparable c a p i t a l ava i l ab le for investment that there is i n NZ about 9% less c a p i t a l avai lable with 2-shift operation and 17% less with 3-shift operation than i n the FRG.

Equipnent cost determines the necessary investment volume. Comparable handling equipment e i t h e r imported or manufactured loca l ly was found to be up t o 20% more expensive than i n the FRG. R-ns are the l imited market volrrme, t he high t ransportat ion cost, sales tax and duty.

3.4 Availabi l i ty And Qualifications Of Workforce

It is s ign i f i can t that t h e number of graduates even in l a rge manufacturing ccmpanies is low. Figure 11 shcus the d i s t r ibu t ion of graduates including NZCE(New Zealand Certificate of Engineering) as a percentage of t h e total number of employees, correlated with the s i z e of t he canpanies. Often graduates are not employed according t o t h e i r s k i l l s , e.g. a chemical engineer is working i n the f i e l d of mechanical engineering.

Fig. 11: Distr ibut ion of graduates i n different-sized canpanies

Considering the exis tence of a manufacturing engineering department, t he s i t ua t ion is similar. As f igu re 12 i l l u s t r a t e s , 10 canpanies or 38% have no such department a t a l l , which means that t h i s task is performed by less-qual i f ied departments such as workshop production. Where manufacturing engineering departments do exist, they employ only a few qua l i f i ed engineers. Only 25% of t he canpanies asked employ a person with s k i l l s i n component handling techniques.

BFtCMI IN WKW.Iffi 9clN3"hG SFPnnMn As I iF ill% WQ 0: W&ES Ih rgpJw,

Fig. 12: Distr ibut ion of engineers i n manufacturing engineering departments

Pa ra l l e l s e x i s t Detween the New Zealand and the Australian s i tua t ion . In AWtralia a considerable shortage of engineers e x i s t s i n manufacturing / lo/ . For example, it h a s been e s t i w t e d that, canpared to Austral ia , there are ten times as many engineers per thousand people working i n manufacturing in the U.S.A., i n Japan twenty times as many, and i n Br i t a in three times. The number of engineers per every thousand people working i n manufacturing i n Australia is between 5.8 and 7.3 / lo/ . I n the N.Z. invest igat ion the number of engineers employed in manufacturing engineering departments per thousand employees was 8.2, s l i g h t l y higher than t h e average Australian f igu re for 1978. The fact t h a t inadequacies exist i n the wnufactur ing planning function i n New Zealand industry is also st rongly supported by the f indings of t h i s invest igat ion.

3.5 Social/human Determinators

Several social/human aspects re la ted to m p o n e n t handling e x i s t , t he main one k i n g t h e th rea t that the improvement of handling workplaces, especial ly when automated, may cause redundancy. To balance the advantages and disadvantages of aut-tion requires decis ions o f t en of a highly controversial p o l i t i c a l nature, involving the three i n t e r e s t g r w p s workers, represented by the unions, employers, represented by the manufacturers' and employers' federat ions, and the general public represented by the government and its ins t i t u t ions .

Within t h e scope of an invest igat ion such as this it is not possible t o discuss all problem areas concerning a u t w t i o n i n s u f f i c i e n t de ta i l , however the study attempted to point out t he ex i s t ing regulations concerning autaaat ion, as well as t h e main a r g m t s for and against automation f rm t he viewpoints of the d i f f e ren t i n t e r e s t groups.

To sunrmarize, no clear regulations, especial ly award agreements, concerning the autanation of handling workplaces, e x i s t i n New Zealand. t he arguments of ten f o n d w i t h employers, unions w i l l generally accept new technology (automation usual ly means new technology), if well informed and involved i n its introduction. On t he s i d e of t h e manufacturers' and employers' federat ions only vague recomaendations e x i s t , aimed a t informing and cooperating with the unions concerned. No state and government l eg i s l a t ion restricting introduction of new technology exis ts . Safety and heal th r egu la t iomare kept very general and only regulate general working conditions. Only few program for redundancy and r e t r a in ing e x i s t . The above gives sane indicat ion of the indus t r i a l background,

i nd i r ec t ly related to c a n w e n t handling, against which the study was performed. 'RE more specific aspects of component handling w i l l nwbe discussed, again with reference to t ab le 1.

However, and t h i s is contradictory to

4.0 N.Z. FINDINGS: CRITERIA ELATED TO M)EIpoNENT HANaING

4.1 General system Design

A general lack of planning i n the overa l l mater ia l handling function w a s evident. I n 39% of t he canpanies invest igated the ove ra l l material handling concept had to be c r i t i c i s e d . 47% of the canpanies admitted never having perfonaed an ana lys i s of their material flow. The main point of c r i t i c i sm was t ha t no s ing le , main material flov d i rec t ion is recognisable. Long t ransport dis tances a r e the r e su l t . Saoetimes succeasive rmnufacturing processes are ca r r i ed out i n p l an t s located far apart from each other. In most of the cases observed the production plant has been expanded by adding areas to the ex i s t ing p l an t without a l t e r i n g the material handling function according t o the new requirements.

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Another problem comoon to New Zealand arises f r m the use of overseas componentry. Often these components are not transported i n standard containers or on standard pa l l e t s , so t ha t t h e i r t r ans fe r to the in t e rna l company t ransport and storage f a c i l i t i e s causes several handling operations. Here a detai led analysis of the ove ra l l handling cost for component manufacturer and cmponent user is missing.

4.2 Storage-related Problems

A s per t h e earlier de f in i t i on of cmponent handling, t he study only d e a l t with storage-related problems in the v i c i n i t y of lnanufacturing uni ts . The basic problems found were (frequency of occurrence, as a percentage of total number of cmpanies invest igated, i n brackets):

- Unsuitable s torage systems (equipment) (43%) - Lack of storage space (25%) - Inappropriate s tock con t ro l (11%)

Unsuitable storage systems were typical . The cmponentry is often put on t he f l o o r , very o f t en i n containers stacked on top of each other , so t h a t pa r t s i den t i f i ca t ion is only possible after an extended search period. Often rack and she l f systems are unable t o carry standard p a l l e t s o r containers. Or there were double or multi-floor s torage layouts only accessible v i a a staircase thus requir ing long t ransport times. Reccmnendations f o r w i n g mainly simple, standard off-the-shelf storage and t ransport equipment, ava i l ab le through local manufacturers and agents , were made.

In 25% of the companies invest igated, a lack of storage space h a s been mentioned i n connection with cmponentry s tored on t ransport ways o r i n machine areas, or with t h e use of outside stores. The r e su l t i ng disadvantages are follow-up operations such as rehandling or sandblasting of canponents rusted in outs ide s tores .

Stock control , especial ly inadequate prts location, preparation and iden t i f i ca t ion , was considered a ser ious problem in 11% of the cmpanies invest igated, and often led to unnecessary labour demands.

4.3 Transport Problems

be sunnarimd as follows: F r m the study, N.Z. company-internal t ransport problems can

- Unsuitable t ransport m e a n s (21%) - Unnecessary rehandling of cmponents (21%) - Cmponentry put i n t ransport way or machining area (21%) - U m k e d t ransport and machining area (13%)

Selection p o s s i b i l i t i e s and a v a i l a b i l i t y of su i t ab le t ransport devices is poor. In 21% of t h e canpanies unsuitable t ransport

such as ba r re l s or sacks d i f f i c u l t fo r handling o r devices m s u i t a b l e fo r protect ing sens i t i ve p a r t s were c r i t i c i s e d . The most c m n f a u l t were p a r t s put on t h e f loo r without considering fb r the r t ransport act ions, leading t o unnecessary parts handling. Transferring cmponents frm a larger i n t o a smaller container f o r easier handling was found t o be another common inadequacy (f igure 13).

Having t r a n s p w t and machining areas not marked (usual ly by painted l i n e s on the f loo r ) scmetimes leads to a very chaot ic mixture o f areas used f o r transport- , storage-, and machining purposes. Many unnecessary handling operations r e su l t . This problem was found i n 13% of the companies. Again it can be expected t h a t this percentage is ac tua l ly considerably higher.

4.4 Workplace-related Problems

problem areas: Workplace-related problems may be grouped under s i x individual

- Unergonomic design of workplaces (57%) - Machine twl loading and unloading (32%) - Indus t r i a l robot appl icat ion (43%) - Feeders and specially-designed loading and unloading

- Multiple tools (such as progression d i e s ) (13%) - Alternative machinery (16%)

equipment (25%)

In 57% of the companies analysed the ergonomic design of individual workplaces was found to be unsatisfactory. Typical inadequacies are e.g. missing support equipment (suspended tools, assembly j igs ) , non-optimised handling sequences (time and mtion s tud ie s ) or unpleasant working conditions (illumination, working posi t ion) . The workplaces c r i t i c i s e d are mainly concer- ned with product assembly, and are operated e igh t hours per day. Because of this high degree of u t i l i s a t i o n , they o f f e r a po ten t i a l for subs t an t i a l savings. So far New Zealand management has not su f f i c i en t ly recognised t h i s opportunity for e f f ec t ing savings. The low percentage of manufacturing engineering departments or of persons responsible fo r the design of workplaces and equipment, are reasons f o r t h e present s i t ua t ion .

Concerning machine too l loading and unloadi , two main inadequacies were f i r s t l y (found i n 14% of the c m z n i e s ) t h e use of unsui table devices for the supply of cauponents a t the machine tool (see also figure 13) , secondly (18%) t h e lack of s u i t a b l e j i g s and clamps f o r posit ioning the cmponents for the mchining operation, i n order to reduce the set-up changes required, and clamping- and machining time.

In 43% of the companies invest igated i n d e t a i l , discussions and t h e analysis of individual workplaces fo r the po ten t i a l appl icat ion of i ndus t r i a l robots and pick-and-place units were performed. For economic (not technical) reasons i t however s e a m unl ikely that i n d u s t r i a l robots w i l l be introduced to any g rea t extent i n t o New Zealand i n the near future , s ince only one of t he cmpanies invest igated uses its machine tools i n +sh i f t operation&.a second one is working a 2x12 hours s h i f t operation. From an econmic viewpoint multi-shift operation is i n most cases a necessary prerequis i te f o r t h e use of i ndus t r i a l robots. The d i s t r ibu t ion of potent ia l technical appl icat ions i n this study is i l l u s t r a t e d i n f igure 14.

Potent ia l i ndus t r i a l robot appl icat ions (data base: %i&iies invest igated)

None of t h e observed workplaces w a s dangerous, nor imposed a d i r e c t health hazard on the worker. However especial ly i n diecast ing (mloading of hot castings, l iqu id metal), forging (hot cmponents, noise) , spraying (poisonous fumes), spotwelding and deburring (sparks, noise) , jobs are unpleasant and monotonous and incorporate certain heal th hazards.

While i n d u s t r i a l robots, through their p rogramab i l i t y and exchangeable gr ippers , o f f e r t h e necessary f l e x i b i l i t y t o deal

Fig. 13: F i l l i n g canponents frm a l a r g e r i n t o a smaller with a l a r g e number Of different cmponents and tasks , feeders container and spec ia l ly designed equipment are l imited i n t h e i r handling

function. Feeders f o r band and s t r i p material may however deal Although unnecessar rehandli of can mts was e x p l i c i t l y with greater material VariatiOrIS, and are therefore offered as

c r i t i c i s e d i n only 21; of all G p a n y repoyts, t h i s seems far too S t a n d a r d equipment. I n t he inves t ig t ion especial ly P m Shops low to be representat ive of t h e ove ra l l s i t ua t ion . were analysed, and it was found i n 25% o f t he ccmfanies that

autanatic equipment could be applied econauically, replacing The acceptance of marked t ransport ways/aisles and machining mainly feeding operations. It was also observed that

areas is generally low. In 21% of the canpanies invest igated, Safety regulat ions are not W e l l regarded in N . Z . p m s shops. the stori OF can ents i n marked areas which should be kept In 14% of the relevant r epor t s -nt - passed on t he free, & s e w 2 It amin be that the ove ra l l mn-existence or mn-use of s a fe ty guards on presses. figure is far higher.

397

Page 6: On the Analysis of Component Handling Technology

Multiple too l s , such as progression d ies , multiple boring bars or multi-spindle too l s reduce the number of individual machining operations required. and consequently reduce t h e handling operations required. The use of multiple tools w a s recomnended i n 13% of t h e canpanies.

Alternat ive machinery, i. e . mchines which reduce handling time by offer ing mxe machining f ea tu res such as machining cen t r e s , has s t a r t e d to make its way i n t o Neu Zealand industry. This is demonstrated by the i n s t a l l a t i o n of numerically control led machinery as show i n f igu re 6. However t h e introduction of K-machine too l s could still be increased subs t an t i a l ly , and has been suggested i n 16% of the invest igated canpanies. These f igu res are ce r t a in ly too low, because the invest igat ion of a l t e r n a t i v e manufacturing technology was not t he main subject of t he study.

The e f f o r t s required to keep up with in t e rna t iona l technologi- c a l developments, or even t o reduce the ex i s t ing technology gap, demand a high degree of i n i t i a t i v e and dedication by a l l groups involved. I f New Zealand manufacturing industry is t o compete internat ional ly , it increasingly has t o adopt and adapt modern m u f a c t u r i n g methods and handling techniques.

A s a consequence of the r e s u l t s of the N.Z. invest igat ion, s t r a t e g i c a l t e rna t ives for the improvement of the component handling s i tua t ion have been developed and evaluated. The s t r a t e g i e s suggested concentrate mainly on improving the know-how on component handling, and include the deve lopen t of a method of ident i fying, analysing and providing solut ions t o component handling problems, including an evaluation technique to determine the investment po ten t i a l of an improvement task. This method is spec i f i ca l ly designed f o r t h e appl icat ion by planning personnel less conversant with handling technology.

REFERENCES 5.0 CONCLUSIONS

With respect to spec i f i c shortcomings i n component handling i n N.Z., Figure 15 s-rizes t h e d i s t r ibu t ion of each individual handling problem analysed. (For example in su f f i c i en t ergonomic d e s i Q of the workplaces has been indent i f ied as the most ffequent problem, viz. i n 57% of t he cmpanies) .

m7fKYff mll(RwT

Fig. 15: Distr ibut ion of problems d i r ec t ly re la ted to component handling

This invest igat ion has shown that there is an excel lent poten- tial for improvements i n t h e component handling function of N.Z. wnufactur ing industry. A very l a rge part of the total improvement may be classified as basic organisat ional problems. Approximately 43% of the total number of problems analysed require only minor c a p i t a l expenditure and offer a short term pyback period. They include:

- lack of planning i n the ove ra l l mater ia l handling function, - inappropriate s tock control , - unnecessary rehandling of cmponentry, - canponentry put i n t ransport a is lesand machining areas, - umwked t ransport and machining areas, - non-ergoncmic design of workplaces.

To so lve the other 57% of t he problems mentioned usually requires a more subs t an t i a l investment, these including:

- unsui table s torage systems; - l ack of storage space; - unsui table t ransport m e a n s ; - inappropriate machine tool loading and unloading; - possible i n d u s t r i a l robot appl icat ion; - feeders and spec ia l ly designed equipment needed; - mult iple t o o l s preferable; - a l t e r n a t i v e machinery better.

I t is s ign i f i can t that t h e main source of a l l problems are management r e spons ib i l i t i e s . They include inadequate planning, and arise from a lack of qua l i f i ed staff with full-time respons ib i l i t y i n canponent handling and i n overal l i ndus t r i a l engineering tasks .

A number of factors w h i c h provide considerable pressure for e f f i c i e n t ccmponent handling i n many overseas countr ies are lacking, or are of much less signif icance i n New Zealand. These include : - low plant u t i l i s a t i o n ;

- comparatively low labour cos t ; - depreciation regulat ion not favouring more e f f i c i e n t

- high cost for local and overseas equipment with p l an t u t i l i s a t i o n ;

l imited ava i l ab i l i t y .

1 . Warnecke, H . J . , R.D. Schraf t : Industr ieroboter , Volume 4, Pmduktionstechnik heute, Krausskopf-Verlag, Mainz, 2nd ed i t i on , 1979.

2. Frank, H.E.: Handhabungseinrichtungen, Volume 13, Prcduktionstechnik heute, Krausskopf-Verlag, Mainz, 1975.

3. Koschnitzki, K.D.: Untersuchung der Problematik in t eg r i e r t e r Material Flussyteme i n der Einzel- und Kleinserienfertigung, Beuth-Verlag, 1975.

4. Merchant, E.M.: Analysis of Existing Technological Forecasts m c e r n i n g the Canputer-Integrated Automatic Factory, CIRP-Annals, Vol. 29/2/1980, pp. 507-512.

5. Scholz, W: Appropriate Canponent Handling Technology for New Zealand Manufacturing Industry, School of Engineering Report No. 276, University of Auckland, 1982.

6. S tua r t , G.F.: Technology and Innovation i n New Zealand Manufacturing Industry: Fmpirical Studies , PEL-Resource Paper 1 , Physics + Engineering Laboratory, Wellington, 1980.

7. Arndt, G. and Warnecke, H.J.: Manufacturing Engineer- ing Research i n New Zealand, CIRP-Annals, Vol. 29/2/1980, PP. 553-558,

8. Arndt, G.: Development of a Manufacturing Engineering C e l l via Student Projects . Proc. 14th CIRP Intern. Seminar on Manufacturing Systems, Tmdheim, 1982.

9. Warnes, P.D.: The Case for NC: An Overview, PEL Report No. S 7863, Physics + Engineering Laboratory, Wellington, 1980.

10. Report of the Task Force on Manufacturing, Vol. 2, The I n s t i t u t i o n of Engineers. Australia, 1979.