A COMPARATIVE ANALYSIS OP VISUAL LAYOUT TECHNIQUES A S A P P L I E D TO MEDIUM S I Z E J O B MACHINE SHOPS A THESIS Presented to the F a c u l t y o f the D i v i s i o n o f Graduate Georgia Institute of In Partial Technology Fulfillment of the Requirements f o r Master of Science in I n d u s t r i a l the Degree Engineering by Earle I s r a e l Denenberg June Studies 195^ A COMPARATIVE ANALYSIS OP VISUAL LAYOUT TECHNIQUES A S A P P L I E D TO MEDIUM S I Z E J O B MACHINE SHOPS Approved: 7^ XP— Date Approved by Chairman; A / / ^ y — 3/\/S>.S<& ii A CKNOWLEDGMENTS F o r his guidance and a i d in p e r f o r m i n g t h i s study, I w i s h t o t h a n k my t h e s i s a d v i s o r , P r o f e s s o r W i l l i a m N « Cox, J r . I also wish to acknowledge the statistical assistance rendered by D r . Joseph J . Moder, the c r i t i c i s m s offered by the rest of the reading constructive committee, and the help p r o v i d e d by D r . Joseph E , Moore on p s y c h o l ­ ogical aspectso F i n a l l y , I w i s h t o r e c o g n i z e my w i f e , Doralee, not only for her c l e r i c a l a i d , but f o r t e c h n i c a l a s s i s t a n c e as w e l l « her iii TABLE OF CONTENTS Page ii . . . iv v vi ACKNOWLEDGMENTS LIST OF TABLES LIST OF ILLUSTRATIONS....... ABSTRACT Chapter I. N I TRODUCTO IN 1 Srta emof entRof hrechProbe lm A eta eseta II. LITERATURE SEARCH. k III. JOB SHOP DEFINED. * li| IV. EXPERM I ENTAL PROCEDURE 17 V. EVALUATO I N AND RESULTS 28 Q u a n ttiitta ttiiv e Analytsiss Q u a n a v e Resul Qual Analytsiss Qualiittati ativ ve e Resul VI. CONCLUSO I NS 38 VII. RECOMMENDATO I NS. i|0 APPENDX I A. A CM ON D E NA SN EC D FOR M OEFRSTHEPRO AM ESR C IDANCOS O CE I TY O F E C H I A L E N G N I E P O E D E FOR STANDARDZ IN I G LAYOUT NOMENCLATURE B. EQUP IMENT LIST - GV I EN CONDT IO I NS l\$ C. PROCEDURE DATA ± i9 D. DATA EVALUATO I N SURVEY AND COMPUTATO I NS 59 E. SAMPLE CALCULATO I NS 76 Bibliography •««••«.... ... o • ....<, o o o 81 0 IV LIST OF TABLES TABLE PAGE 1 • MACHINERY INDUS TRY 2. PLANT 3. COST A N A L Y S I S . . . . • II. TIME 5. FLEXIBILITY 6. DECISION 7. SUMMATION 8. STATISTICAL . LAYOUT COMPARISON • C H A R T . . . . . . . . 2 O••<»•• 11 O ELEMENT.. « 30 *.. THEORY EVALUATION. OF DATA EVALUATION.« TABULATION 29 31 «. 33 « • . . « .• O. 36 36 V L I S T OP ILLUSTRATIONS Figure Page 1. Sketch of Machine Shop . . . . . . • • . < . . . 2. Rough S k e t c h o f F l o o r P l a n and P r e l i m i n a r y E q u i p m e n t and F a c i l i t y A r e a s • • • < • < , ••••«•• 22 3. Method I - D r a f t i n g 21+ ij.. Method I I - Templets 5. Method I I I - Models 6 Method I V - Templets and M 0 »• » 18 «, 25 »•••••••• o d e l s . o.. 26 • 27 v i ABSTRACT V i s u a l i n l a y o u t a p p l i c a t i o n t o l a r g e e n t e r p r i s e s w h i l e t e c h n i q u e s . The w h i c h s e v e r a l b e s t o r o f t h e s a t i s f y t e c h n i q u e s s c a l e s m a l l e r p u r p o s e t h e o r g e n e r a l l y m a s s o f t h i s r e q u i r e m e n t s h a v e t h e s i s o f o f i s t o t y p i c a l l i m i t e d t y p e s s e l d o m o f u s e d s u c h d e t e r m i n e s c i e n t i f i c a b e e n p r o d u c t i o n e n t e r p r i s e s t e c h n i q u e s l a y o u t w o u l d j o b s h o p l a y o u t m a c h i n e s h o p was r e - l a y o u t . S p e c i f i c a l l y , s e l e c t e d a s t h e a a r e a medium o f s t u d y t h e medium s i z e j o b s h o p , a c c o r d a n c e w i t h t h e d e f i n i t i o n . p e r s o n n e l , a r r a n g e d a n d b y e a c h t e m p l e t s f i r s t a n d t e c h n i q u e m e t h o d s i n t e c h n i q u e s . i n i t i a l q u e n t t y p i c a l o f f o u r s h o p The was a s s u m e d d u p l i c a t e d p r o v i d e a u s i n g b a s i s p r o v i d e d a s t a n d a r d s e q u e n c e t o m i n i m i z e l e a r n i n g s h o p t e c h n i q u e s : f o l l o w i n g o p e r a t i o n s (1) c o s t c r i t e r i a f o r o f t h e l a b o r w e r e t h e p r o c e d u r e f o r o f m a t e r i a l s , o f was m o d e l s , b y t h e o t h e r o f t h e d u r i n g c o n s i d e r e d e v a l u a t i o n a n d shop c o m p a r i s o n l a y o u t o r d e r t h e o f r e c o r d i n c o n d i t i o n s o b t a i n e d d e t a i l e d l a y o u t s o f o f e a c h i n t e m p l e t s , l a y o u t w e l l d e f i n i n g s e l e c t e d f a c i l i t i e s , f i n a l e n t e r p r i s e A f t e r m e t h o d s - - d r a f t i n g , m o d e l s . t o t r a d e s . W i t h a n d t y p e A The j o b a t h i s w o r k i n g e q u i p m e n t , was t u r n m e t a l j o b s i n c e t h e s p a c e , s m a l l e r s i z e r e p r e s e n t s i n h a v e t h e t h e s u b s e ­ e f f e c t s . s i g n i f i c a n t l a y o u t (2) t i m e vii I required to accomplish layout, i n terms o f a d d i t i o n a l (3) f l e x i b i l i t y o f t h e labor cost and time f o r layout re-arrangement, (!+) e d u c a t i o n a l l e v e l r e q u i r e d t o p e r f o r m t h e l a y o u t , (5) mental a b i l i t y required by the layout technician, (6) p e r c e p t i o n and u t i l i z a t i o n technician, a n d (7) a t t a i n e d by the layout d e c i s i o n i n f l u e n c e on management• a n d (3) w e r e e v a l u a t e d q u a n t i t a t i v e l y ; were a n a l y z e d s t a t i s t i c a l l y naires distributed Factors space (1), the remaining (2), factors from data obtained by question­ to Industrial engineering graduate students and p r o f e s s o r s . W i t h i n the scope o f t h i s p r o b l e m , the conclusions t a i n e d d i d n o t s p e c i f y a n y one p a r t i c u l a r universal application to technique job shop o p e r a t i o n s . ob­ for Instead, it was d e t e r m i n e d t h a t t h e m o d e l t e c h n i q u e was b e s t c h o i c e w h e r e t i m e l i m i t a t i o n was t h e g o v e r n i n g f a c t o r , w h i l e t h e t e c h n i q u e was p r e f e r r e d w h e r e c a p i t a l minimized. templet I n v e s t m e n t had t o be Where time l i m i t a t i o n and c a p i t a l are o f approximately equal importance, the expenditure statistical a n a l y s i s designates the model technique as p r e f e r a b l e . One r e c o m m e n d a t i o n i s p r o p o s e d as t h e r e s u l t r e v i e w o f the space p e r c e p t i o n d a t a . The r e s u l t s review tend to indicate that the q u a l i t a t i v e of of the this evaluation of this f a c t o r is acceptable; however, the development of a quantitative e v a l u a t i o n , in accordance with the procedure g e s t e d , would e s t a b l i s h the f a c t o r more d e f i n i t e l y . suggested t h a t the f a c t o r o f space p e r c e p t i o n and It sug­ is utilization b e d e f i n e d f e e t o n t h e m o r e a c c u r a t e l y e v a l u a t i o n . i n o r d e r t o q u a n t i f y i t s 1 CHAPTER I INTRODUCTION Statement o f t h e p r o b l e m . - " I n d u s t r y has been constantly exposed to discussions o f research on t h e applications of visual layout techniques and their r e l a t i v e merits as applied to large scale o r production type activities 0 Attempts t o apply s c i e n t i f i c layout procedures to the a s m a l l e r i n d u s t r i a l a c t i v i t i e s and j o b type shops have g e n e r a l l y been neglected o r discouraged u s u a l l y because o f preconceived opinions o f impracticability and excessive expense. I t is the purpose o f this paper t o present a comparative analysis o f representative visual plant techniques as applied to a job shop. shop has been chosen as t h e s p e c i f i c this research. layout A medium s i z e machine design l i m i t a t i o n f o r Theobjective o f the investigation is to determine t h e most e f f e c t i v e method o f l a y o u t f o r a t y p i c a l machine shop. A r e a o f r e s e a r c h . - - S i n c e l a y o u t i n t h e j o b shop has g e n e r a l l y received only casual attention from the industrial engineering p o i n t o f v i e w , a n a t t e m p t w i l l be made t o show t h a t a t l e a s t a T h e 1951 U n i t e d S t a t e s Bureau o f Census r e p o r t s t h a t e a c h o f 2 1 6 , 0 0 0 m a n u f a c t u r i n g e n t e r p r i s e s (90 p e r c e n t o f t h e t o t a l ) employ 100 persons o r l e s s , w h i l e t h e r e m a i n i n g 2l±,000 e s t a b l i s h m e n t s e a c h e m p l o y m o r e t h a n 1 0 0 e m p l o y e e s . M a n u f a c t u r i n g e n t e r p r i s e s o f l e s s t h a n 100 employees a r e usually classified as the smaller businesses. 2 one o f p r o v e the s e v e r a l f e a s i b l e shopo To p r o b l e m s e l e c t e d C h a p t e r t w e n t y I I , t o t h e The m e d i u m , a n d v a r i a b l e s o f s t u d y . s i z e j o b w i t h a S t a t e s t r a d e w h i c h e n t e r j o b m a c h i n e B a s e d i n a i n t o j o b a s h o p was d e f i n i t i o n s w o u l d e m p l o y m a c h i n e t o o l s n u m b e r i n g the T a b l e s h o w n t h e m a c h i n e r y i n d u s t r y a a s i n t o 1 . i n w h o l e i n f r o m f r o m 1 . , M a c h i n e r y D i s t r i b u t i o n Number o f E s t a b l i s h ­ o f n o t c l a s s i f y d e t a i l the B u r e a u ( e x c l u d i n g e m p l o y e e d o e s f i n e b e t w e e n H o w e v e r , s t a t i s t i c s , T a b l e C e n s u s ( 1 ) s e p a r a t i o n s h o p s . d i v i d e d o f s u f f i c i e n t l y f o l l o w i n g E m p l o y e e s o n w o u l d s h o p B u r e a u i n t o d e f i n i t e l a r g e i s l a y o u t a p p l i c a t i o n s i z e t h e m a c h i n e r y ) f o r p l a n t s e v e n t y - f i v e . s h o p make v i s u a l medium p e r s o n s U n i t e d m a c h i n e a c t u a l l y a r e a a medium f i f t y to many t h i s , t h e o f s a t i s f a c t o r y t h e a s f o r t w e n t y - f i v e t h e and l i m i t s u c h m e t h o d s s m a l l , h a s to to p r e p a r e d s h o w how e l e c t r i c a l groups© I n d u s t r y Number o f E m p l o y e e s m e n t s 1-9 10-1+9 50-99 100-1+99 500-999 1000+ T o t a l Number 3 3 , 8 8 3 1 2 8 , 6 5 7 9 3 , 6 2 9 1 , 6 9 6 3 7 0 , ^ 8 322 226,li+8 290 6 9 2 , 5 5 8 1 7 , 9 0 6 1 , 5 4 5 , 3 2 3 3 THE MACHINERY INDUSTRY IS THEN BROKEN DOWN INTO SEVERAL CATEGORIES, ONE OF WHICH IS THE MACHINE SHOPS. OF THE TOTAL MACHINERY INDUSTRY, THE MACHINE SHOP DIVISION HAS 3»H2 ESTABLISHMENTS AND 58,160 EMPLOYEES, OR 17 PER CENT AND 3«$ P©R CENT, RESPECTIVELY. THE RATIO OF ESTABLISH­ MENTS TO EMPLOYEES IS FOUND TO BE SIGNIFICANTLY HIGHER THAN IN THE OTHER CATEGORIES, INDICATING THAT MORE SHOPS WITH FEW MEN PREVAIL IN THE MACHINE SHOP TRADE THAN IN ALLIED MACHINERY ESTABLISHMENTS. THIS WOULD LEAD TO A GENERAL CONCLUSION THAT MACHINE SHOP ACTIVITIES PREDOMINATE IN THE 1-100 EMPLOYEE CLASS ALMOST EXCLUSIVELY, WHICH THEREFORE ESTABLISHES THE AREA OF MACHINE SHOP PRACTICE. CHAPTER LITERATURE The II SEARCH subject of s c i e n t i f i c plant layout is rela­ t i v e l y new to t h e f i e l d o f i n d u s t r i a l e n g i n e e r i n g . Its a p p e a r a n c e became e v i d e n t d u r i n g t h e s e c o n d q u a r t e r of the t w e n t i e t h century. Practically all the pertinent l i t e r a t u r e u n c o v e r e d was c i t e d i n c a s e h i s t o r i e s forty selected periodicals, o f some which excluded s e v e r a l books w r i t t e n during the past eight y e a r s . exceptions, the reference material W i t h one o r two dealt only with layout in production type enterprises plant o f medium and large s i z e w i t h 100 o r m o r e e m p l o y e e s * The p r o b l e m s e n c o u n t e r e d t h i r t y t o f o r t y years ago l a y i n g out a p l a n t are c l o s e l y a l l i e d to the problems present day i n d u s t r y . with advancing W i t h t h e a d v e n t o f mass p r o d u c t i o n , the introduction of However, the methods o f s o l v i n g problems have changed s i g n i f i c a n t l y o f the automobile these technology. synonymous w i t h In the early part o f the t w e n t i e t h c e n t u r y , a change s t a r t e d to take place in the layout procedures of factories. for machinery tapped from a central N o l o n g e r was p o w e r line shaft; no l o n g e r machines and benches permanently p o s i t i o n e d ( 2 ) . ing knowledge and i n t e l l i g e n t a p p l i c a t i o n in The of safety m o t i o n and time s t u d i e s , and economic p l a n n i n g , to were increas­ procedures, mention 5 ONLY A FEW FACTORS, INCREASED THE IMPORTANCE OF BETTER LAYOUT PLANNING TECHNIQUES. THE DEVELOPMENT OF PRODUCT AND PROCESS PLANNING, WHICH WAS EVIDENCED BETWEEN 1920-1930, MEANT THAT THERE COULD EVOLVE MORE THAN ONE OR TWO SOUND LAYOUTS FOR A NEW OR REMODELED FACTORY.(3) IN THE EARLIER DAYS OF THE SMALL JOB SHOP, THE LAYOUT WAS USUALLY left to THE EXPERIENCED JUDGMENT OF THE SHOP OWNER. THE OWNER, WHO HAD THE ABILITY AND INCLINATION TO EXPRESS HIS THOUGHTS ON PAPER IN THE FORM OF ROUGH SKETCHES, WAS SIGNIFICANTLY MORE EFFICIENT IN HIS PLANNING THAN THOSE WHO COULD NOT DRAW OR THOSE WHO HAD A LIMITED KNOWLEDGE OF MACHINE SHOP PRACTICE. AS SHOPS GREW INTO FACTORIES, IT ALSO BECAME INCREAS­ INGLY IMPORTANT TO APPLY SOUND JUDGMENT AND TECHNICAL KNOWLEDGE IN THE INITIAL PLANNING STAGE. PROCESS CHARTS AND FLOW DIAGRAMS FIRST APPEARED SOMETIME DURING THIS TRANSITION PERIOD; HOWEVER, NO DEFINITE DATE COULD BE ESTABLISHED AS TO WHEN THESE CHARTS AND DIAGRAMS WERE INITIATED. UNDOUBT­ EDLY, SOME SHOP OWNERS HAD CONCEIVED CRUDE VARIATIONS OF THESE METHODS WHICH THEY ADOPTED TO THEIR OWN NEEDS LONG BEFORE THESE METHODS BECAME KNOWN AS INDUSTRIAL PLANNING. NOW THAT INDUSTRY HAD SOME UNDERSTANDING OF WHAT WAS NEEDED TO EQUIP THE FACTORIES, THE LACK OF AN EFFICIENT METHOD OF PLANNING THE PLACEMENT OF MACHINES, MEN AND EQUIPMENT BECAME MORE APPARENT. TRIAL AND ERROR METHODS WERE VERY COSTLY. DRAWINGS WERE TEDIOUS, TIME CONSUMING, 6 and consequently, expensive. templets and more r e c e n t l y , answered part of the G r a d u a l l y , the use o f cardboard three dimensional models have challenge. The purpose o f these a i d s to p l a n n i n g i s n o t only to help layout personnel with t h e i r problems, but also f a c i l i t a t e the use o f the r e s u l t s o f t h e i r e f f o r t s to in c o n v i n c i n g management t h a t a d o p t i o n o f the p r o p o s e d method is d e s i r a b l e . In industry, when new l a y o u t s a r e p r o p o s e d , o r when p r e s e n t l a y o u t s a r e t o be a l t e r e d , management u s u a l l y has t o make t h e f i n a l d e c i s i o n f o r a c c e p t a n c e re jection 0 V i s u a l l a y o u t techniques emanate from several basic methods: I• Drawings A. B. II• plan view drafting 1. Blueprints 2. Whiteprints Isometric drawings Templets--two dimensional A. Block templets B# Contour C. V a r i a t i o n s o f c o n t o u r t e m p l e t s made o f templets plastic or photosensitive III. Models--three dimensional A. Block models B. Contour models C. P r o t o t y p e models film or 7 The d r a w i n g t e c h n i q u e as o u t l i n e d above is explanatory. self- T e m p l e t s e x i s t m a i n l y i n two t y p e s . The f i r s t is the b l o c k templet which is n o t h i n g more t h a n a r e c t a n g u l a r piece o f cardboard cut to the o v e r a l l dimensions. it differs contour plan The o t h e r t y p e is t h e two d i m e n s i o n a l from the former In that it templet; is cut to the (with overruns of moving parts) general o f the machine or implement and u s u a l l y has a p l a n v i e w d r a w i n g p r i n t e d on it.(5) A v a r i a t i o n o f the templet that is becoming increas­ ingly popular consists of one-eighth inch transparent plastic p h o t o g r a p h i c a l l y p r i n t e d on one s i d e w i t h the templet of a particular in the p l a s t i c machine. Small magnets imbedded serve to hold the templet to a metal layout board,(6) Scale models are also found in comparable types those o f the templets. to I n one c a s e , the s i m p l e wooden b l o c k is u s e d , w h i c h g i v e s no i n d i c a t i o n C o n t o u r models do n o t d i s p l a y a l l of contour at the features o f all. the m a c h i n e b u t m e r e l y p r e s e n t t h e g e n e r a l s h a p e , so t h a t p i e c e can be r e a d i l y i d e n t i f i e d . of several different materials of the machinery. P r o t o t y p e models are to produce a detailed Sometimes b a l s a wood is carved to the desired accuracy. Colored s t r i n g is throughout the p l a n t « cast replica painstakingly used w i t h t e m p l e t s as w e l l as models to i l l u s t r a t e flow of materials the often the 8 R e c e n t l y , three dimensional models have been combined w i t h templets in i n d u s t r i a l planning work* The model shows t h e a c t u a l m a c h i n e i n t h r e e d i m e n s i o n s the templet which Is placed under the model table travel, projections, T h e u s e o f a l/V = l although variations f and necessary indicates clearances•(7) g r i d has been u s e d i n most I n s c a l e f r o m 1/32" while t o 1" = l instances, 1 have been encountered. The r e p r o d u c t i o n o f l a y o u t s f o r p u r p o s e s o f display, f o r r e c o r d s , and f o r o t h e r m u l t i - c o p y uses has d e v e l o p e d w i t h t h e i n c r e a s e d demands f o r b e t t e r l a y o u t The f o r e m o s t m e t h o d o f r e p r o d u c t i o n graphy. techniques. i s b y means o f p h o t o ­ Photostats are used e f f e c t i v e l y in conjunction w i t h templets, e s p e c i a l l y w i t h the magnetic p l a s t i c and the photographic n e g a t i v e t e m p l e t . ( 8 ) processes similar of blueprints White prints to o z a l i d are f r e q u e n t l y employed or photostats. the necessity of any a d d i t i o n a l times, photographs are taken directly model or t e m p l e t . master p r i n t . ( 9 ) preparation. Often­ o f the l a y o u t , be U s u a l l y , small sections it o f the l a y o u t are pieced together to form a then the Once the l a y o u t has b e e n r e p r o d u c e d , The p r i n t s produced p r o v i d e a n e a t , are single can t h e n be d i s m a n t l e d a n d t h e components r e u s e d f o r planning. repro­ templets photographed separately to reduce d i s t o r t i o n , several pictures or instead Direct, clear, uniform d u c t i o n s may be o b t a i n e d i n t h i s manner f r o m without templet it future compact 9 r e c o r d o f w h a t a c t i o n was f i n a l l y taken or o f what c o u r s e s c o u l d be f o l l o w e d sometime i n t h e Several efficient possible future. methods have been found f o r filing l a r g e and space-consuming l a y o u t s when t h e y a r e n o t i n u s e . Templets are sometimes s t o r e d v e r t i c a l l y on sheets four by eight foot plywood double-hung similar to of windows. To o b t a i n a l a y o u t o f a c e r t a i n p o r t i o n o f a p l a n t , the c o u n t e r - b a l a n c e d b o a r d i s m e r e l y p u l l e d down o u t o f its filing position.(10) Models are u s u a l l y stored in sections of specially built cabinets. in drawers They are a l s o s t o r e d by making them i n t o a d i s p l a y complete w i t h a t r a n s p a r e n t s h e l l the building and a r e p l i c a provide an a t t r a c t i v e o f the surrounding areas exhiblt was t h e s i g n i f i c a n t chemical industries and models.(11) to 0 One o f t h e c o n c l u s i o n s r e a c h e d a f t e r case h i s t o r i e s of the r e v i e w o f r o l e p l a y e d by the i n the use o f t h r e e dimensional Construction of p i l o t plant or drawings unit operations, which required detailed layout of piping, tanks, a n d o t h e r p r o c e s s i n g a p p a r a t u s , was a i d e d i m m e a s u r a b l y b y f i r s t building in miniature. to r e a l i z e the merits Other industries o f models as w e l l as were soon templets. The e x t e n s i v e use o f models i n t h e a u t o m o t i v e Is r e c o g n i z e d by the i n t r i c a t e their layouts. detail incorporated industry in The C h r y s l e r C o r p o r a t i o n b u i l d s models moving p a r t s , while a t y p i c a l with l a y o u t o f t h e F o r d Company 1 0 d e p i c t s s u c h d e t a i l s c o l u m n s . ( 1 2 ) ( 1 3 ) o f p l a n t i s l a y o u t The i n c l a t u r e , f o r m s u c h e f f o r t t o a n d t o o l s , t h e o f p r o p o s e d m o u n t e d e x a m p l e s i n d u s t r i e s a n d t h e A m e r i c a n s m a l l o n w a l l s e x e m p l i f y the s i z e g e n e r a l l y s h o p t h e w o r k g o a l s t h e t o a n d s t a t u s w h i c h a n d a r e p r o d u c t i o n l a r g e l y t h r o u g h w h i m s , o f k e y c a t i o n o f f o r m a l I n the i t b c a n be a t h e n e x t some T h e o f t o t h a t the d i v i d i n g m o o t p o i n t ; c h a p t e r a b b r e v i a t e d t i m e h a d the p r o d u c t i o n p r o c e s s t o o f e n d o r s e d s h o p , b y m u c h t h e t h e o f h a s b e e n t e c h n i q u e s . same m a n n e r d e c a d e s and w h i c h v i r t u e l a y o u t s e v e r a l b y p r o p o s a l . v a r i a b i l i t y , ^ j u d g m e n t t h a n s h o p t h i s n o t j o b v i s u a l i n p l a n n e d t h e a n t h e s e a r c h , t o d a y r a t h e r f o l l o w i n g N o t e o n M e c h a n i c a l c o d e , A t nomen­ a g o o f t e n , - p e r s o n a l s c i e n t i f i c a p p l i ­ t e c h n i q u e s . p r e s e n t e d a l t h o u g h w e r e o f a f o r e - m e n t i o n e d r e s p e c t p r e p a r e d p e r s o n s ; p r i s e s , (11+) t h e w i t h r e l i a n c e a p p l i e d i s t h e e x t r e m e s h o p s t e c h n i q u e s p a p e r . f r o m A . p r o c e d u r e , A s s o c i a t i o n l i t e r a t u r e d i s r e g a r d e d l a y o u t s m o d e l A p p e n d i x i n c l u d i n g t h e l a y o u t S o c i e t y a n d S t a n d a r d s s i g n i f i c a n t l y l o t A m e r i c a n i n s t a n d a r d s T h r o u g h o u t s t a n d a r d i z e t e m p l e t a p p e a r s l a y o u t d i f f e r s a w h i c h w r i t i n g , a s s w i t c h e s p r e c e d i n g a n E n g i n e e r s Job a c t u a l a i m e d . I n a n y a s w i l l c h a r t , t h e f o r l a r g e s c a l e d r a w i n g b l o c k b e t w e e n u s e d s e v e r a l p r o d u c t i o n w i t h the i s n o t c h a r a c t e r i s t i c s d e f i n i t i o n a v o i d a n d s e t a m b i g u i t y . l a y o u t t y p e r e s u l t s p r o d u c t i o n t h e t o o r o f t e c h n i q u e t e m p l e t h o w e v e r , be c o n c e n s u s c o m p a r i s o n t h e l i n e a o f e n t e r ­ t h i s i n c l u d e d , a r e j o b s i m i l a r . s h o p s f o r t h i n Block Templet Table 2. Plant Layout Comparison Chart 2-Dimension Templet 3-Dimension Templet Combination of 2 and 3 Dimen­ sion Templet Cost Low f i r s t c o s t . C a n be made b y inexperienced personnel. Requires services of a f a i r l y skil­ led draftsman with a knowledge o f machine t o o l s . F i r s t cost con­ siderably higher than for block templet. Requires skilled model maker i f made s p e c i a l . Most models n o t yet available commercially. Cost o f models in q u a n t i t y not a p ­ preciably higher t h a n good 2 dimen­ sion templets. I n i t i a l cost of this method combines the cost o f 2 dimension templets with 3 dimension models. Engineering Value V e r y p o o r . Does not permit good visualization of layout or effective ar­ rangements . Good. This type of templet in the hands o f a p r o ­ f i c i e n t engineer permits very ef­ fective layouts. Does n o t p e r m i t easy i n t e r p r e t a ­ t i o n o f the l a y ­ out by non-tech­ nical personnel. G o o d . Makes f a s t ­ er development of equipment a r ­ rangements f o r effective lay­ outs . Helps to ' s e l l ' the layout. Best. Combines a l l the merits o f 2 dimension templet and 3 dimension model. Table 2 . B l o c k Templet P l a n t Layout Comparison Chart 2-Dimension Templet (Continued) 3-Dimension Templet Combination o f 2 and 3 Dimen­ s i o n Templet Advantages Can be made q u i c k l y at very low c o s t . Gives a very a c ­ curate layout and r e d u c e s time r e q u i r e d t o make f i n a l drawings. Clearly indica­ tes actual f l o o r areas required. S e r v e s as a p e r ­ manent t e m p l e t when p r o p e r l y made. Greatly reduces p o s s i ­ b i l i t y of errors as compared t o block templets. Aids v i s u a l i z a ­ t i o n o f layouts by n o n - t e c h n i ­ cal personnel. V a r i o u s schemes c a n be p h o t o ­ g r a p h e d f o r com­ parison studies. Models c a n be used i n d e f i n i t e ­ ly. Permits h i g h l y a c ­ curate layouts to be made q u i c k l y w i t h c o m p l e t e engin­ eering d e t a i l s . Gives f u l l v i s u a l ­ ization of layout. Only one s e t o f models necessary t o make any number of layouts. Re­ d u c e s l a y o u t and drafting c o s t . Disadvantages Does n o t p r o v i d e for accuracy of layout, effective arrangements or economical u t i l ­ ization of floor space. Increases d r a f t i n g time and cost of engineer­ ing drawings. Cost i s c o n s i d e r ­ a b l y h i g h e r than block templets. Does n o t p r o v i d e ease o f p e r c e p t ­ i b i l i t y inherent in models. Re­ quires engineers to carry mental­ l y a l l planning Does n o t c a r r y the engineering i n f o r ­ mation provided by the 2 dimen­ sion templet. Does n o t show machine c l e a r ­ ances r e q u i r e d for operations or s e r v i c e s . In- Highest i n i t i a l o f any m e t h o d . cost Table 2 . B l o c k Templet P l a n t Layout Comparison Chart 2-Dimension Templet 3-Dimension Templet Disadvantages Posters discrepa n c i e s and e r r o r s . Increases o v e r a l l layout c o s t . (Continued) in the t h i r d dimension. f (Con d) creases time. drafting Combination o f 2 and 3 Dimen­ s i o n Templet Ik CHAPTER JOB SHOP A specific III DEFINED d e f i n i t i o n o f t h e term " j o b shop" has not been a v a i l a b l e to i n d u s t r y . I n s t e a d , i n d u s t r y has included i n the scope o f t h i s term a n y t h i n g from a model shop t o s o m e t h i n g s h o r t o f t h e macs p r o d u c t i o n t y p e enter­ prises characterized by the automobile i n d u s t r i e s . The General E l e c t r i c Company, I n p l a n n i n g i t s Engineering L a b o r a t o r i e s , set f o r t h the following c r i t e r i a which for r e a s o n s o f common v i e w p o i n t s a t i s f y t h e d e f i n i t i o n o f small job shops.(15) lo Short order jobs—work o f u s u a l l y eight hours or 2. Number o f employees r a n g i n g f r o m s i x t o 3. Number o f machine t o o l s r a n g i n g f r o m t w e l v e twenty-five, less. ten, to C o l v i n a n d S t a n l e y l i m i t t h e s m a l l j o b shop to one employing less than twenty-five persons which, they suggest, reflects t h e common o p i n i o n , ( 1 6 ) It is n o t a b l e t h a t o n l y m e t a l working or machine shops a r e c i t e d f o r d e f i n i t i o n . T h e m o s t common o f n o n - metal trades in the job shop c a t e g o r y is the industry. one printing The small job p r i n t i n g shop u s u a l l y employs f r o m to t h r e e workers and has two or t h r e e p r e s s e s . shops, however, have several c h a r a c t e r i s t i c s which All will job 15 d i s t i n g u i s h them from the p r o d u c t i o n t y p e o f LO Within a particular industry, enterprise: job shops will p e r f o r m more jobs o f l e s s q u a n t i t y t h a n p r o ­ duction shops 2. e J o b shops have a s p e c i f i c o r d e r q u a n t i t y is r u n i n one s e t - u p . which The job is u s u a l l y a-kind and is seldom repeated e x a c t l y . one-of- Production shops may s e t up f o r s h o r t q u a n t i t y runs t o customer schedules. fulfill R e t o o l i n g w o u l d be r e q u i r e d f o r each p e r i o d when a c e r t a i n q u a n t i t y is t o be 3« delivered. J o b shops tend t o employ m u l t i - s k i l l e d workers as differentiated from the production type industry w h i c h employs p e r s o n s who a r e t r a i n e d t o o p e r a t e a s p e c i f i c t y p e o f m a c h i n e , such as a type o f punch press or t u r r e t l a t h e . J o b shop p e r s o n n e l can be c l a s s i f i e d i n two c a t e g o r i e s — t h e mechanic and the a s s i s t a n t mechanic (or trainee), the d i f f e r e n c e being t h a t t h e mechanic has mastered the use o f a l l equipment associated w i t h t h e trade« 4 # A v a r i e t y o f work w i l l e v e n t u a l l y confront the job shop whereas t h e p r o d u c t i o n s h o p , even t h o u g h may h a v e t o r e t o o l f o r d i f f e r e n t jobs, It will e s s e n t i a l l y b e c o n c e r n e d w i t h t h e same g e n e r a l type o f manufacture i t has a l r e a d y experienced. This requires the use o f universal type tools in 16 the job shop and c o n v e r s e l y , would predominately u t i l i z e the production special shop purpose machinery* 5. J o b shop o p e r a t i o n s employ fewer workers s m a l l , medium, and l a r g e class in the establishments c o m p a r e d t o t h e same c l a s s i f i c a t i o n s in as production type shops* 6. Mass p r o d u c t i o n t e c h n i q u e s a r e l e s s common a n d l e s s o f t e n o b s e r v e d i n a job shop t h a n in t i o n shops p r i m a r i l y production. because o f smaller Assembly operations observed intermingled are produc­ quantity usually with fabrication operations i n j o b shopsO The q u a l i f i c a t i o n s arid f o r above are q u a l i t a t i v e that reason are d i f f i c u l t to measure. definitions in nature These a r e b y no means r i g i d , b u t a r e i n t e n d e d to s e r v e as t h e c r i t e r i a o f a job shop f o r t h e p u r p o s e of this research. 17 CHAPTER IV EXPERIMENTAL PROCEDURE The methods o f i l l u s t r a t i n g l a y o u t s have expanded to o f f e r s e v e r a l a l t e r n a t i v e c h o i c e s as new m a t e r i a l s t o o l s have b e e n d e v e l o p e d . from f o u r b a s i c t y p e s : m o d e l s , and However, a l l (1) drafting, templets and m o d e l s . techniques (2) templets, These f o u r (3) repre­ j o b machine s h o p p r o b l e m . I d e a l l y , a l a y o u t c o u l d be d e s c r i b e d a s most if evolve fundamental p r o c e d u r e s have b e e n s e l e c t e d f o r a p p l i c a t i o n t o a sentative t h e b u i l d i n g were d e s i g n e d a r o u n d t h e f i n a l fortunately, i n d u s t r i a l planning c o n f i n e d to s t r u c t u r e s already efficient product. today is almost wholly In order t o simulate t y p i c a l p r o b l e m o f a medium s i z e j o b s h o p , a b u i l d i n g by e i g h t y f e e t (columns t h i r t y f e e t w a l l s , and s i x t e e n f e e t Figure 1. on c e n t e r s ) sixty foot was a r b i t r a r i l y c h o s e n . dimensions o f d o o r s , overhead c l e a r a n c e s , By a p p l y i n g e a c h l a y o u t t e c h n i q u e approximate etc. to a standardized c o n d i t i o n s in each c a s e , a comparison can be made on the b a s i s of time, f a c t o r s as e x p l a i n e d i n Chapter V , the f i r s t a i n from e i g h t shows a s k e t c h o f the b u i l d i n g w i t h problem with i d e n t i c a l Un­ in existence or buildings h o u s i n g the p r e s e n t a c t i v i t i e s . feet and c o s t , and s e v e r a l other The l a y o u t r e s u l t i n g from method p e r f o r m e d becomes the o b j e c t i v e l a y o u t for 19 each other method in t u r n , to f a c i l i t a t e comparison. each method were used to o b t a i n a l a y o u t different If from t h a t o f each o t h e r m e t h o d , c o m p a r i s o n would be h i n d e r e d by the i n t r o d u c t i o n of this additional In addition thirty-five variable. to the selected b u i l d i n g miscellaneous p r o d u c t i o n machines and three persons were chosen to s a t i s f y definition. To f u r t h e r dimensions, the medium s i z e job supplement the given Appendix B summarizes a l l twentyshop conditions, equipment, f a c i l i t i e s , and services i n c l u d e d i n the procedure o f each m e t h o d . Two p r e m i s e s w e r e m a d e b e f o r e t h e p r o c e d u r e w a s started. F i r s t , i f any person technically techniques were to f o l l o w this text, trained in the procedures as o u t l i n e d regardless o f the degree o f experience. time t a k e n t o d e t e r m i n e w h i c h move i s b e t h e same r e g a r d l e s s neglig­ Second, t o be made n e x t o f the method used. r e q u i r e d t o make the move p h y s i c a l l y , known to in the time r a t i o o f methods would remain the same, o r t h e time d i f f e r e n t i a l w o u l d be so s m a l l as t o be ible, layout the will The time however, is definitely vary. The methods used a r e as follows: Method I. Drafting (modified block templets II. Templets (contour) III. IV. Models (prototype) Templets and Models III. drafted) superimposed) (combination of I I . and 20 Method I I was a r b i t r a r i l y p e r f o r m e d f i r s t the s t a n d a r d l a y o u t ; to develop Method IV was n e x t a p p l i e d t o a v o i d t h e n e c e s s i t y o f d u p l i c a t i n g e v e r y move common t o b o t h m e t h o d s ; Methods I I I and I f o l l o w e d . was made t o p e r f o r m e a c h method a t the A deliberate same p a c e . effort Every move p e r f o r m e d In Method I I was r e c o r d e d and t i m e d t o nearest minute. Any e r r o r s made i n Method I I were a l s o r e c o r d e d and f o l l o w e d as the other methods. s t a n d a r d p r o c e d u r e by the This was done i n o r d e r t o c o n t r o l carry-over learning effect the o f one method t o the B e f o r e any move was made, the time r e q u i r e d the other. to 0 deliberate where a p i e c e o f equipment s h o u l d be p l a c e d was r e c o r d e d , t h i s time b e i n g e x a c t l y the was u s e d f i r s t . A p p e n d i x C shows t h e o r i g i n a l and t i m e d a t a w i t h " t h i n k " added t o " a c t " same i r r e s p e c t i v e o f w h i c h method operation t i m e s l i s t e d under Method I I t i m e s o f e a c h method t o e s t a b l i s h but total times f o r each method. The g i v e n c o n d i t i o n s o f e x i s t i n g b u i l d i n g , required, and equipment were s u r v e y e d f i r s t . facilities Methods I , II, and IV r e q u i r e d r o u g h s k e t c h e s w i t h d i m e n s i o n s t o b e made from c P r a c t i c e e f f e c t s were i n v e s t i g a t e d from the p s y c h o l ­ o g i c a l viewpoint to determine t h e i r importance i n t h i s application. A s t u d y o f r e c a l l , r e m i n i s c e n s e , r e t e n t i o n and memory on i n d i v i d u a l d i f f e r e n c e s , d i s t r i b u t i o n o f p r a c t i c e , and whole o r p a r t l e a r n i n g r e v e a l e d l i t t l e e f f e c t on t h i s s t u d y b e c a u s e ( 1 ) a r e l a t i v e l y s m a l l amount o f r e p e t i t i o n was p e r f o r m e d , ( 2 ) e a c h t r i a l was r e p e a t e d b y a d i f f e r e n t m e t h o d , and ( 3 ) s u f f i c i e n t c o n t r o l was r e t a i n e d o v e r the s t i m u l i , p r o c e d u r e , and r e s p o n s e t o n e g a t e t h e p r a c t i c e e f f e c t s • ( 1 7 ) ( 1 8 ) 21 manufacturers 1 c a t a l o g s o r from the Templets drawn i n I n d i a existing i n k from t h e s e equipment. sketches followed the p r o p o s e d A m e r i c a n S o c i e t y o f M e c h a n i c a l E n g i n e e r s s t a n d a r d s as o u t l i n e d i n A p p e n d i x A . however, to include a l l the It was n o t i n f o r m a t i o n on t h e b e c a u s e o f t h e v a r i e t y and s i n g u l a r i t y necessary, templets o f the machine F o l l o w i n g normal l a y o u t p r o c e d u r e , r e g a r d l e s s of t e c h n i q u e a p p l i e d , a s k e t c h was made o f the b u i l d i n g p l a n , n o t i n g e x i t s and o b s t r u c t i o n s . It is at this tools. the floor point t h a t t h e g e n e r a l a r e a s o f e a c h s e r v i c e o r f a c i l i t y were determined. the r i g h t For e x a m p l e , due t o t h e half o f the b u i l d i n g , i n e r y and f a b r i c a t i o n travel o f crane over the l o c a t i o n o f heavy mach­ s h o u l d be w i t h i n t h i s a r e a ; the supply room s h o u l d be c l o s e t o t h e r e c e i v i n g d o o r , whereas t h e should be c l o s e t o the f r o n t entrance working a r e a . sketch, a pre-grouping of machines I n making t h e as w e l l as n e a r office the the i n e a c h a r e a was r o u g h l y drawn as shown i n F i g u r e 2 . ^ No a t t e m p t w i l l be made t o d e f e n d t h e a c t u a l ment o f equipment and f a c i l i t i e s although reasonable arrange­ layout t o l e r a n c e s were o b s e r v e d . d I n t h i s c a s e , equipment was l a i d o u t a c c o r d i n g t o a p a t t e r n d e v e l o p e d by t h e a u t h o r a t t h e machine shop o f t h e G e o r g i a I n s t i t u t e o f T e c h n o l o g y E n g i n e e r i n g Experiment Station.(19) The l a t h e s , m i l l i n g m a c h i n e s , and b e n c h e s were f o u n d t o be c l o s e l y r e l a t e d b y c o l l e c t i n g i n f o r m a t i o n from p a s t work o r d e r s ( S e e A p p e n d i x B ) . This d i f f e r s from t h e c o n v e n t i o n a l c o l o n y t y p e l a y o u t u s u a l l y employed b e c a u s e o f s o - c a l l e d u n p r e d i c t a b l e p r o d u c t and p r o c e s s v a r i a t i o n . 0 22 P i g . 2 tfOUGH 5K£fCH Of ftOOtf PLAN ANP PtffUMlNARV PQU/PM£AiT AND FACILITY AREAS 23 After t h e b u i l d i n g o u t l i n e was e s t a b l i s h e d , p r o d u c t i o n e q u i p m e n t was p l o t t e d previously assigned. under the influence in the general the areas Rearrangement o f the equipment of process flow, materials a i s l e space, and similar layout f a c t o r s . followed handling, The supply and t o o l r o o m f o l l o w e d I n m u c h t h e same p r o c e d u r e a s d i d men's l a v a t o r y and the o f f i c e s . Machinery units l e f t o f the l a y o u t u n t i l the f a c i l i t i e s were t e m p o r a r i l y lished, were now i n s e r t e d in the space a l l o t e d . ment o f equipment and p a r t i t i o n s needed a f t e r was t e n t a t i v e l y found. the out estab­ Rearrange­ the layout c o m p l e t e d w e r e made as d i s c r e p a n c i e s were A g a i n , during the f i n a l stages o f the l a y o u t (oper­ a t i o n s 13 A , B , a n d D o f A p p e n d i x C ) , c h a n g e s t o p r o v i d e a b e t t e r arrangement were f o u n d n e c e s s a r y . Construction t h e b r i d g e c r a n e s y s t e m was c o n f i n e d t o M e t h o d s I I I as t h e o t h e r methods were n o t s u i t a b l e ing projections. of and I V f o r showing overhang­ P l a n view photographs of each method are shown on the f o l l o w i n g p a g e s . METHOD I • Dl Pig. 3 Fig. k 26 Pig. 5 27 28 CHAPTER V EVALUATION AND RESULTS The e v a l u a t i o n o f l a y o u t methods consisted o f a combination o f quantitative and q u a l i t a t i v e studies. Quantitative analysis.—Included in the quantitative eval­ u a t i o n a r e t h e cost o f t h e l a y o u t i n terms o f l a b o r a n d material, t h e time r e q u i r e d t o perform t h e l a y o u t , a n d t h e degree o f f l e x i b i l i t y i n c r e a t i n g t h e l a y o u t and making changes• The a s s i g n m e n t o f a d e f i n i t e m o n e t a r y v a l u e t o l a b o r Is a d i f f i c u l t t a s k a s s e c t i o n s o f t h e l a y o u t may be p e r f o r m ­ ed b y n o n - t e c h n i c a l p e r s o n n e l w i t h a $200/month s a l a r y , o r by p r o f e s s i o n a l e n g i n e e r s w i t h $ 9 0 0 / m o n t h s a l a r y . F o r purposes o f comparison, t h e t y p i c a l salary o f a n i n d u s t r i a l engineering trained supervisor was ( a b o u t |600/month o r $3.50/hour) used f o r a l l operations i n each method. Cited costs o f m a t e r i a l were purchase p r i c e s a t l o c a l a r c h i t e c t s ' houses o r q u o t a t i o n s from " V i s u a l " P l a n t L a y o u t s Oakmont, Pennsylvania. pared i n the following Time and m a t e r i a l supply Inc., data were p r e ­ t a b l e s , summarized from Appendix C F l e x i b i l i t y was d e t e r m i n e d b y c o m p u t i n g t h e t i m e and expense i n v o l v e d i n r e a r r a n g i n g t h e l a y o u t a s shown b y O p e r a t i o n s 6B, 7 B , 8 B , 9B, 1 0 B , 1 1 , a n d 1 3 E i n T a b l e 5. T a b l e 3. Method Cost Analysis Material Labor Cost a t $3.50/Hr. I II III $69.23 51.62 24.88 None 1 S c o t c h Tape 1 s1/h2e1e t 2i-1/V grid R o l l o f l/V x S c o t c h Tape 1 L1/u 2 ' x 2' 1/V grid cite board R o l l o f 1/V 15 L u c l t e c o l u m n s 12" o u t s i d e w a l l s V inside partitions 130 m o d e l s Crane s y s t e m ( h a n d made) IV 61.95 Same m a t e r i a l s Method I I I as i n Material Cost Total Cost Cost Ratio None 169.23 1.30 #1.15 .55 0 "1.6 1.15 1 ..0 0 178 1.0 20 5 72.5.000 311 0) 358.5.V 53.27 1 383.28 7.19 3581 .+0 1*203 .5 7.90 30 T a b l e 4* Time E l e m e n t Method Time i n Honrs Time R a t i o I II III IV 19.78 14.75 7.11 17.70 2.78 2.08 1.00 2.49 By s u b s t i t u t i n g ly different variations results appeared. o f each method significant­ F o rexample, i f ready-made t e m p l e t s were p u r c h a s e d i n s t e a d o f made i n M e t h o d I I , t h e cost o f time i n Table of material E |79.13. similar increased The time i n 3. d e c r e a s e d t o §23.63 a n d t h e c o s t t o $55.50, p r e s e n t i n g a n e w t o t a l o f T a b l e 4* d e c r e a s e d b y e i g h t h o u r s . A decrease i n labor cost, increase i n material a n d d e c r e a s e i n t i m e was e v i d e n t i n M e t h o d I V . cost O f course, these variations a r e contingent on the a v a i l a b i l i t y of the exact templets needed. If t h e crane assembly i n Methods I I I a n d I V c o u l d be purchased, t h e cost o f these methods would be decreased i n time a n d increased I n m a t e r i a l ; these layouts would have a f f o r d e d a b e t t e r comparison t o Methods I and I I cannot s a t i s f a c t o r i l y which i l l u s t r a t e the crane assembly. Q u a n t i t a t i v e r e s u l t s . — T h e q u a n t i t a t i v e a n a l y s i s shows Method I I t o be favored s i g n i f i c a n t l y i n terms o f cost and f l e x i b i l i t y , b u t only second best i n time. e Accordingly, Quoted from " V i s u a l " Plant Layouts I n c . , Oakmont, P a . T a b l e 5. Flexibility Method Operation II I IV III Time i n Hours Labor Cost $ Time I n Hours Labor Cost # Time i n Hours Labor Cost $ Time i n Hours Labor Cost ! 6B 2.63 9.21 0.35 1.23 0.75 2.63 0.35 1.23 7B 0.85 2.97 0.25 0.87 0.47 1.65 0.25 0.87 8B 0.78 2.73 0 20 0.70 o.J+2 1.47 0.20 0.70 9B 0.73 2.55 1.05 0.ii8 1.68 11 0.25 13E 2.88 4.31 0.87 10.08 1.47 2.38 1.05 1.23 0.42 0.68 0.20 10B 0.30 0.^8 Total 9.35 $32.72 Ratio 5.114- o 1.68 * 0.24 0.84 0,59 1.82 $6.37 3.33 1 •JI- •>«• 2.07 0.78 2.73 $11.67 2.36 $8.26 1.83 #Too s m a l l t o be s i g n i f i c a n t 1.30 32 Method I I w o u l d be c h o s e n ; sounder basis i f it w o u l d be s e l e c t e d on a t h e a s s u m p t i o n c o u l d be made t h a t t i m e , terms o f o v e r - t i m e hours a n d / o r purchased t e m p l e t s , in could be m o r e e a s i l y p r o c u r e d i n a j o b s h o p t h a n c o u l d c a p i t a l investment. 1:7.19 for The 2 0 8 ; l time r a t i o would then overbalance the o cost r a t i o in Methods I I and III, Q u a l i t a t i v e a n a l y s i s , - - F o u r factors which are d i f f i c u l t precise measurement enter into the selection o f the layout technique f o r the job shop, namely; r e q u i r e d t o do t h e l a y o u t , best (1) t h e e d u c a ­ t i o n a l l e v e l required to perform the l a y o u t , effort of (2) t h e m e n t a l f3) t h e s p a c e perception and u t i l i z a t i o n a t t a i n e d by the l a y o u t t e c h n i c i a n , and (li) the decision influence on management. level The e d u c a t i o n a l f a c t o r would q u e s t i o n the use o f the l a y o u t techniques the equivalent a b i l i t y o f a technician, or even a mechanic. with engineer, executive, The second c o n s i d e r a t i o n would w e i g h the r a t i o o f s e l f e v i d e n t procedure t o matters deep t h o u g h t a n d c o n s t a n t s e a r c h i n g , requiring Given a specific l e n g t h o f time to perform a l a y o u t , space p e r c e p t i o n and utilization would test the r e l a t i v e technique. The i n f l u e n c e d e c i s i o n on management q u e s t i o n s the coraprehensibility effectiveness of of the respective results each obtained t h r o u g h use o f techniques by the p o l i c y - m a k e r s w i t h i n the industrial enterprise. I n o r d e r t o a r r i v e a t some s i g n i f i c a n t conclusion, f o r m o f d e c i s i o n t h e o r y was e m p l o y e d t o w e i g h t h e a b o v e a 33 factors.(20) In essence, this theory proposes that for each probe lm there can be see l cted several meh tods of solution (Mi) whcih will in turn result in several possible acto i ns (Aj). The probabilty (Pij - i meh tods with j possible actions) that a meh tod will produce a certain acto i n is one of the consd i erato i ns in makn ig the decs io i n whcih is the choc ie of the best a l yout meh tod. The chances of success Iin i any situation must be estm i ated; however, the best decs io in will not aw l ays depend on the hg i hest probabilty atan i ed i sn i ce the resulting acto i ns (Aj) shoud l be assg i ned ranked vau l es in accordance with an individual's preference. By assg i nn i g A^ with an evau l ato i n factor (Ej - a measure of i individual preference) the best decs io i n may now be deter­ mn ied by the meh tod whcih maxm i zies P^jEj. If w t o meh tods of solution M ( _] and M) were to be decd ied upon, each producn i three results (Ai, A, and A3), selection of one by rankn ig ao lne mg i ht produce one decs io i n whereas co l ser investigation by assg i nn iT gabe vlau le s D(Ei ,s En, TahnedoryE^) to thne results and 6. e c i o i E v a u l a t o i weg ihn ig each Ej in each probabilty coud l produce a diferent d io in= —6) a moe rAac(E cur= ate5)one. A F3or (E ex=am l: le <cs 1 1)pe l = 10 P12= 2 13 = 3 M 21= 3 P =7 23= 8 2 2 2 A E 2 2 M 3 p P 2 P 22 34 i n T a b l e 6 . w h e r e S P ( M ) = 15 1 w o u l d l e a n t o w a r d Hg* and 2 P ( M ) = 1 8 , the 1 i However, by a s s i g n i n g E j t o each A j and w e i g h t i n g these v a l u e s , the r e s u l t s are: P 2 P i J ( V = P E + ? E + 11 1 12 2 = (60) + ( 1 0 ) + = 73 2P l t j choice 2 (M ) = ^21^1 P + 2 = P E + 22 2 (35) (18) + E 13 3 (3) E 233 + (8) = 61 This is a r e v e r s a l o f the decision in f a v o r o f M^; latter the case b e i n g more a c c u r a t e . The P ^ j i s d e t e r m i n e d b y t h e i n d i v i d u a l ' s o f how w e l l t h e A j w i l l s a t i s f y estimate the given s i t u a t i o n (or effectiveness) with comparison to other P ^ j ' s , e t c , a selected linear scale. The E j is d e t e r m i n e d by ranking the A j in order o f r e l a t i v e consideration of value. importance, On a l i n e a r the values E 2 given first without scale, values are then t e n t a t i v e l y assigned to the A . , (Ej) S t a r t i n g w i t h A]_, , E ^ , • • • E ^ . are checked f o r t h e i r relative w i t h E-j_ b y q u e s t i o n i n g t h e p r e f e r e n c e o f A ^ o v e r t h e ation A 0 + A~ + •••A, , ^3 k Eg, E ^ , •••Ej c decision, 2 A^,o,,A^, A I f A_ <, = , > A 0 previous relationships the a p p l i c a t i o n combin­ the k m u s t be a l t e r e d a r i t h m e t i c a l l y a n d so f o r t h . rank + A . + A, , then 1 ^ 3 is chosen n e x t to t e s t its to s a t i s f y the relationship When n u m e r i c a l the of changes are made, s h o u l d n o t be d i s t u r b e d u n l e s s of t h i s process the reasoning is in changed. 35 A p p l i c a t i o n o f t h e d e c i s i o n t h e o r y was a c c o m p l i s h e d by asking ten graduate i n d u s t r i a l engineering students l i t t l e layout experience and four i n d u s t r i a l with engineering professors w i t h moderate but not extensive experience rate the p r o b a b i l i t i e s of effort, (A-^) e d u c a t i o n a l l e v e l , ( A ^ ) space p e r c e p t i o n , and ( A ^ ) d e c i s i o n under the p o s s i b l e methods (M^) d r a f t i n g , m o d e l s , and (M^) templets and m o d e l s . to ( A ) mental 2 influence (M 3 t e m p l e t s , (M^) They were then asked to evaluate A-^, A ^ , A ^ , and A ^ by a s s i g n i n g values E ^ ,E E ^ , a n d E^_ s i m i l a r t o t h e p r e v i o u s e x a m p l e . 2 F o r a more d e t a i l e d account o f the i n f o r m a t i o n asked, a copy o f data e v a l u a t i o n survey is included in Appendix D together with the r e s u l t s o f each participant. The c o m p u t a t i o n p r o c e d u r e o f t h e s o l i c i t e d data a p p e a r s o n d a t a e v a l u a t i o n s h e e t number one o n l y , as other procedures are similar. Since the i n d i v i d u a l e v a l u a t i o n s d i f f e r e d w i d e l y i n s c a l e , r e s u l t s were into a per cent value o f 100 f o r raw transformed shown i n A s t a t i s t i c a l a n a l y s i s o f the r e s u l t s o f m e t h o d i s s h o w n i n T a b l e 8. all comparison. A t a b u l a t i o n of the adjusted r e s u l t s is Table 7» each where X is the a r i t h m e t i c average and s is the unbiased estimate o f the standard d e v i a t i o n the f o u r t e e n determinations of f o r each method. The f i r s t h y p o t h e s i s t e s t e d i s the f o u r methods are homogeneous. i n T a b l e 8., , that the variances of I n terms o f the d a t a shown this would imply that the results f o r each 36 Table 7. Summation o f Data E v a l u a t i o n Participant Method I 1. 2. 3. k. 5, 6 6 7 8. 9. 10o 11. 12, 13. Ik. io.5 17a 8.6 12.9 12.9 i|-6 0 ik.o k.5 2I+.3 13.1 15.2 13.7 10.3 IV III II 20.3 21.0 32.1 31.3 37.1 30.5 15.5 25.k SO.k 27.9 22.0 29.7 42.0 37.0 33.0 26.6 2k.k 26.8 21.9 16.1 18.6 23.3 19.8 17.7 25.2 36.3 lf-1.7 35.7 26.1 28.2 31.6 29.7 18.5 34.2 Table 8. S t a t i s t i c a l 28.2 il-1.2 26.3 38.9 25.4 31 37.0 .k Tabulation Method I s II IV III 11.5 21.2 3 L 9 35.3 6.0 3.9 5.8 6.7 m e t h o d h a d t h e same d i s p e r s i o n o r v a r i a b i l i t y . This hypothesis was t e s t e d s t a t i s t i c a l l y b y t h e u s e o f B a r t l e t t ' s Test.(21) The r e s u l t s o f t h i s t e s t i n d i c a t e d t h a t t h i s h y p o t h e s i s o f homogeneity o f variances is reasonable, since the P value obtained did not approach significance. all tests can be found i n A p p e n d i x E . The calculations f o r 37 Since the hypothesis o f equal variances is accepted, the method p r e f e r e n c e shown b y t h e Ts 1 ficance. was t e s t e d f o r signi­ T h e s e c o n d h y p o t h e s i s m a d e i s t h a t e a c h X" i s n o t significantly different from t h e o t h e r s , o r no one method was p r e f e r r e d o v e r a n y o t h e r . closest preference ratings Methods I I I and I V w i t h t h e were s e l e c t e d f i r s t using S t u d e n t ' s t distribution(22) f o r t e s t i n g t h e d i f f e r e n c e b e ­ tween p a i r s o f sample means. T h e sample v a l u e f o r t was l.lj.8, a v a l u e w h i c h i s n o t c o n s i d e r e d s t a t i s t i c a l l y ficant. Methods I and I I having t h e next l a r g e s t o f X's w e r e t h e n t e s t e d . o f X's at less t h a n t h e 0.25 Since the differences o f the remaining are larger differences are difference T h e s a m p l e v a l u e f o r t w a s 5»07* a value which is significant level. signi­ than t h e case j u s t c i t e d , per cent combinations all other significant* Q u a l i t a t i v e r e s u l t s . — T h e conclusions reached i n the quali­ tative analysis section are that choice, (2) M e t h o d I I I s a b e t t e r C3) M e t h o d s I I I a n d I V a r e b e s t . (1) M e t h o d I i s t h e p o o r e s t selection than Method I, and A l t h o u g h Method I V does have a h i g h e r T than Method I I I , t h i s d i f f e r e n c e f o u n d t o be s t a t i s t i c a l l y s i g n i f i c a n t o f t h e o t h e r X ' s were f o u n d t o be was n o t whereas t h e d i f f e r e n c e s significant. 38 CHAPTER V I CONCLUSIONS The r e s u l t s different o f each e v a l u a t i o n a n a l y s i s optimum methods. specify I f t h e two e v a l u a t i o n s had r e s o l v e d i n t o t h e same a n s w e r , t h e r e i n f o r c e m e n t o f o n e s o l u t i o n upon the o t h e r would have l e f t no doubt as t o best the selection. Upon i n s p e c t i o n o f the space p e r c e p t i o n and data, it utilization was f o u n d t h a t t h e p r e m i s e o f e q u a l " t h i n k " times does n o t n e c e s s a r i l y h o l d t r u e because o f the v a r i e d a s s i g n ­ ment o f v a l u e s i n each m e t h o d . It is assumed t h a t using any l a y o u t technique the f i n a l space by utilization w o u l d be t h e s a m e , as d e s i g n e d i n t h e e x p e r i m e n t . This means t h a t space p e r c e p t i o n m u s t v a r y f r o m one m e t h o d to the next which also infers times f o r Method I I , times. "Think" the i n i t i a l procedure, would remain same w h i l e M e t h o d I " t h i n k " of varying "think" the t i m e s w o u l d be i n c r e a s e d b e c a u s e the low values assigned " C . " in the evaluation data survey sheet. Conversely, "think" times f o r Methods I I I and I V would be d e c r e a s e d because o f the h i g h v a l u e s a s s i g n e d " C " . The o v e r a l l t i m e e l e m e n t s w o u l d be c h a n g e d c o r r e s ­ p o n d i n g l y , decreasing the costs o f Methods I I I increasing the time r a t i o o f Method I I I and I V with I I . p o s s i b l y lead to the conclusion t h a t Methods I I I while This would and I V could 39 be p r e f e r r e d q u a n t i t a t i v e l y s e l e c t i n g Methods I I I as w e l l as q u a l i t a t i v e l y a n d / o r I V as t h e b e s t choice. In view of the previous considerations, s t a t e m e n t s can be p o s t u l a t e d . III, the model t e c h n i q u e , three (1) F o r m a c h i n e s h o p where time l i m i t a t i o n is the most i m p o r t a n t thereby factor, is the best choice. general layouts Method For (2) m a c h i n e shop l a y o u t s where c a p i t a l i n v e s t m e n t m u s t be minimized, Method I I , factory. (3) Method I I or I I I , reinforcement the templet t e c h n i q u e , is most Where t h e r e is a q u e s t i o n o f u s i n g Method I I I satis­ either s h o u l d be s e l e c t e d because o f by the q u a l i t a t i v e analysis. CHAPTER VII RECOMMENDATIONS Although it was q u a l i t a t i v e l y perception varies with the "think" several layout techniques, it determined that time r e q u i r e d in this paper. effect the procedure or conclusions An effort the is the o p i n i o n o f the a u t h o r t h a t t h e s e times would n o t be s i g n i f i c a n t l y to invalidate space changed so as presented in s h o u l d be made t o q u a n t i f y t h e true o f t h i s phenomenon f o r the purpose o f a c c e p t i n g rejecting the previous conclusions. Rather than perform a duplicate in this work, it or is suggested that test of the several different problem problems be d e s i g n e d , e a c h t o b e p e r f o r m e d o n l y o n c e a n d e a c h p r o b l e m t o be s o l v e d w i t h a d i f f e r e n t method. In t h i s way, any person p e r f o r m i n g the l a y o u t would n o t use any method more t h a n o n c e , n o r w o u l d h e w o r k t h e same p r o b l e m m o r e t h a n o n c e . For purpose of comparison, participants w i t h as n e a r t h e same b a c k g r o u n d i n l a y o u t e x p e r i e n c e m u s t be T h e y s h o u l d be t i m e d i n d e p e n d e n t l y t o s u f f i c i e n t l y "think" times from other time. A complete a n a l y s i s c o u l d be used t o e v a l u a t e t h e selected. distinguish statistical results. APPENDIX A AMERICAN PROPOSED CODE CONDENSED SOCIETY FOR OF A FORM OF THE MECHANICAL STANDARDIZING ENGINEERS LAYOUT NOMENCLATURE 42 A CONDENSED FORM O F T H E AMERICAN SOCIETY OF MECHANICAL ENGINEERS PROPOSED CODE F O R STANDARDIZING LAYOUT NOMENCLATURE (23) Templets.--The standard covers two-dimensional, oneplane templets and three-dimensional equipment models. T e m p l e t s c a l e i s 1/4 i n . e q u a l s 1 f t . , U . S . m e a s u r e . This scale is standard w i t h a r c h i t e c t s , e n g i n e e r s , f u r n i ­ ture and equipment manufacturers, e t c , f o r planning p u r p o s e s . E q u i p m e n t o u t l i n e s a r e those which would be made a r o u n d t h e p e r i p h e r y o f a p i e c e o f e q u i p m e n t b y a plumb l i n e h e l d 7 f t . above the f l o o r , and passed around the o u t l i n e o f the m a c h i n e . P r o j e c t i o n s such as w h e e l s , h a n d l e s , e t c , a r e s e p a r a t e l y i n d i c a t e d as d e t a i l s n o t i n the p e r i p h e r y . D e t a i l s o n t h e t e m p l e t a r e t h o s e n e c e s s a r y t o make i t d i s t i n g u i s h a b l e and to l o c a t e important p o i n t s . Kinds and r e l a t i v e weights of lines used a r e : F i x e d o u t l i n e of machine t o o l or equipment Thick solid line D e t a i l parts and substructures Thin solid line Clearances f o r moving parts of machine t o o l or equipment Thick dash l i n e Overhead or underground elements, foundation pits, service clearances and o t h e r elements important to the templet •••Medium dot-anddash l i n e Center lines • Thin dot-and-dash line Clearances f o r movable p a r t s , access and operation are shown i n dash l i n e s . T e m p l e t s do n o t i n c l u d e storage, service or other space. I n t e r f e r e n c e s a r e i n d i c a t e d by medium d o t - a n d - d a s h lines and are included i n f i n a l drawings. Data on the templets i n c l u d e s : over-all length, width, height, including travel clearance but not operator or feed clearances. Weight and h o r s e ­ power are g i v e n . S p e c i f i c a t i o n s f o r i d e n t i f i c a t i o n a r e : model or s t y l e , name, s i z e , u s e r company i d e n t i f i c a t i o n marks or numbers. O p e r a t o r p o s i t i o n Is shown b y a s h o r t h e a v y a r r o w . Other data included are controls, service provisions, power c o n n e c t i o n p o i n t s , and s i m i l a r indicators of necessary a u x i l i a r y o p e r a t i n g f a c i l i t i e s . k3 Templets should be printed on 110 l b . , or more, index b r i s t o l or similar durable stock. It i s preferable to use colored stock: Machine tools and other operating or production equipment • • • • .Salmon Office equipment and standard factory equipmentb i n s , racks, locker room equipment, t o i l e t and washroom f a c i l i t i e s * * Green Materials handling equipment ••••••Yellow A u x i l i a r i e s - p a l l e t s , s k i d s , tote boxes, t r a y s , pans, e t c » • • • • • • • • • • • • • • • • • • - R e d 0 Models.—Three dimensional scale representations of equipment and f a c i l i t i e s , c a l l e d models, are made from wood, metal or p l a s t i c by appropriate processes, in­ cluding tool and machine fashioning, die c a s t i n g , and p l a s t i c production methods. The scale i s the same as that for templets, 1/1+ i n . equals 1 f t . , U. S. measure. Details included are those s u f f i c i e n t , without d i s ­ t o r t i o n , to identify the model and show i t s important structural and operating features for ready i d e n t i f i c a t i o n of the equipment and indication of i t s operating require­ ments so far as plant layout i s concerned. Control points and hazard areas are shown, with a l l controls and operating or moving parts located in neutral p o s i t i o n , no moving parts being designed into the model unless I t is impossible to show them in any other way. Models are made in finishes and colors as near as possible to the actual item represented-including multiple f i n i s h e s , as in o f f i c e furniture. Machine-tool model finishes should follow the recommend ations of the National Machine Tool Builders A s s o c i a t i o n . Machined surfaces can be shown by aluminum paint. Control points should be shown by l i g h t buff paint, conforming to the present-day p r a c t i c e s for greater v i s i b i l i t y and s a f e t y . The p r a c t i c e of the individual company should be followed where models are used exclu­ s i v e l y for a company. Allowances and clearances should not be exaggerated. Accompanying templets should show these allowances for extreme operating and service conditions, but should not include any operator or f a c i l i t i e s allowances, as stated above under discussion of templets. These accompanying templets should carrjr at l e a s t name or description and model number, and, i f p o s s i b l e , type, s i z e , maximum dimensions, certer l i n e s , weight, e t c . , and data on over­ head and underfloor requirements. Models should be durable, not e a s i l y damaged, have a l a s t i n g f i n i s h , and have s u f f i c i e n t weight to stay in position when placed, or be equipped with holes in the base for insertion of fastening p i n s . kk A l l necessary i d e n t i f i c a t i o n markings—name, number, s i z e , d e s c r i p t i o n , e t c . s h o u l d be g i v e n i n a b b r e v i a t e d form and in the most s u i t a b l e p l a c e . M o d e l s s h o u l d be so d e s i g n e d a s t o be u s e d w i t h accompanying standard templets f o r the i d e n t i c a l equip­ ment. This p r o v i s i o n f a c i l i t a t e s drawing the l a y o u t on the f l o o r plan. APPENDIX B EQUIPMENT LIST - GIVEN CONDITIONS EQUIPMENT LIST - GIVEN CONDITIONS Production Area 12-Lathes Universal Turret 1-Gisholt # 3 Turret 3-LeBlond Engine, 1 0 " , 1 2 " , 1 6 " I-II4." Warner and S w a s e y E n g i n e 1 - l i j . " P r a t t and W h i t n e y E n g i n e 1 - R i v e t t P r e c i s i o n (Cabinet) 5>-#3 6 - M i l l i n g Machines 3 - B r o w n and S h a r p e # 2 V e r t i c a l 1-Milwaukee Horizontal 1-Cincinnati #3 Plain 1 - B r o w n and S h a r p e # 2 P l a i n 1 - C i n c i n n a t i 21}." S h a p e r Ii--Drill P r e s s e s 1-Cincinnati-Bickford 1-8" Sho-speed 1-llj." D e l t a P e d e s t a l 1-Knight Boring M i l l Radial 1 - 2 2 Ton L & J Punch P r e s s 2-Grinders 1 - B r o w n and S h a r p e # 2 S u r f a c e 1-Hammond Heavy Duty T o o l 1 - R a c i n e Hack Saw W3BX 2 - D o - A l l HP-36 Band Saws 2-Welders 1 - D i r e c t C u r r e n t A r c on t r u c k 3 ' x 6' x ij. 1-Heliarc l 1 1-Denison Arbor 1L.-Benches 6-3' x 5' 2-3' x 8' 1-2 1 / 2 ' x 1-2' x 8' 2 - 3 ' x 6' 1 - 5 ' x i|.' 1-2' x 5 1 8» x 2 ' x 3' Press EQUIPMENT L I S T - GIVEN CONDITIONS Production Area 1-Water (CONTINUED) (Con'd) Fountain 26-Machine Stands 1 1 / 2 ' x 2' l-Foreman*s x3» Desk 1 - 5 Ton Bridge Crane Assembly S u p p l y a n d T o o l Room 3-3' x 1 0 » x 6' I-I4.8" Bins and Shelving Rotabin 1 - B e n c h 2 ' x 1±» 1-Dial Platform Scale 2' x 3 1/2" x 1-12" Delta Pedestal D r i l l 1-10" S o u t h Bend L a t h e 1 - C i n c i n n a t i #2 P r e c i s i o n 2-Stock Racks 1 - 2 1 / 2 ' x 6 ' x 6' 1 - 2 ' x 9 l / 2 » x 6» Men's Lavatory 2-Toilets 2-Urinals 2 - C i r c u l a r ii 1 Wash Basins 2-Benches 1 1 / 2 ' x 1 0 ' 6-Lockers 1 ' Ladies' 1-Toilet 1-Sink x I4.' Lavatory Press Grinder 3' EQUIPMENT L I S T - GIVEN CONDITIONS Offices 3-Desks 1-Typist 1-60" 1-72" 3-Letter Piles 23 P e r s o n n e l (or operators) 3-Office 1 - S u p p l y a n d T o o l Room 19-Production (CONTINUED) APPENDIX C ROCEDURE DATA PROCEDURE DATA METHOD I Operation 1 . Review given condi­ tions of problem; l i s t requirements for equipment and services. 2. Sketch and measure tools and equip­ ment from manufac­ turers catalogs or actual f a c i l i t i e s . Act 20 III II Total 20 3130 3*30 3. Draw templets, ink in contours and controls, and cut out. il. Draw sketch of build­ ing floor plan; de­ termine general ser­ vice areas with regard for building design; sketch approximate grouping of a l l i e d equipment within areas. (Times in Hours and Minutes) Think Act Total Act 20 20 20 3130 3.30 IV Total 20 3130 3:30 8.00 85OO 35 35 35 35 Act 20 Total 20 3.30 3:30 85OO 8:00 35 35 35 35 PROCEDURE DATA I Operation 5. A . Draw building outline with e x i s t i n g doors and columns. B. Tape i n b u i l d ­ ing outline with existing doors and columns. C. Cut plastic walls to length and glue to baseboard to form building o u t l i n e ; glue in columns and doors. Sub-Total: Act 20 (CONTINUED) II Total Think Act 6. A . D r a w o r p l a c e production tools with a l l i e d equip­ ment in general areas bearing in mind the o v e r a l l arrangement r e ­ quired in exist­ ing f a c i l i t i e s . 2:03 B« R e a r r a n g e t h e following equip­ ment (with mach­ ine stands) in the given o r d e r : Total Act IV Total Act Total 20 07 20 III 20 2:03 07 59 59 07 07 59 59 0l\. 0J+ 11 11 07 07 59 59 1:06 0i+ 1:06 0k PROCEDURE DATA (CONTINUED) I Operation Act l)LeBlond En­ gine Lathe with Brown and Sharpe #2 V e r t i c a l mill. 2)Turret lathe with #3 heavy duty grinder. 3)Two #3 Uni­ v e r s a l Tur­ ret lathes with two Brown and Sharpe #2 Vertical mills. 1±) Small LeBlond lathe with boring m i l l 5)Brown and Sharpe #2 Vertical mill with turret lathe. 6)#3 Turret lathe with Brown and Sharpe #3 Plain m i l l . 7)Remove from layout: Boring mill 0 II Total Think Act III Total Act Total IV Act Total PROCEDURE DATA (CONTINUED) I Operation Act II Total Think Act III Total Act IV Total Act Total LeBlondEngine lathe Turret lathe Radial D r i l l Hack Saw 2 - D o - a l l saws B&S #2 V e r t i ­ cal m i l l Porman s desk 2-welders ! 8)Brown and Sharpe Surface grinder. 9) C i n c i n n a t i Shaper w i t h bench 10)Punch Press with Slo-speed D r i l l press 1 1 ) 3*™benches 12)5-benches 2:23 2:38 S\lfc) — T O t a l t — — — — ——>— — — —> 2+: 2 6 k ' M 7. A . Draw or place S u p p l y and T o o l Room e q u i p ­ ment in general area. B« R e a r r a n g e t h e following equipment in the given order: 16 16 15 15 06 21 _ — — — — — ___ 30 k$ __— _____ 06 — —— 21 —— — — — — — — — 10 25 hi 56 10 25 02 02 05 05 02 02 PROCEDURE DATA I Operation 1)Shelving and racks 2 ) S h e l v i n g and racks 3)Stock rack Ij.)Rotabin 5)Draw o r p l a c e temporary partitions 6)10" lathe with bench 7)Grinder with D r i l l Press 8)Move i n s i d e partition 9)Stock rack Act 1+1 (CONTINUED) II Total 51 Think Act III Total Act IV Total Act Total 10 05 15 18 28 05 15 10 07 17 23 33 07 17 01 01 02 02 01 01 Sub-Total: 57 8. A . D r a w o r p l a c e men's l a v a t o r y equipment in general area, 17 B. R e a r r a n g e t h e following equip­ ment i n the given order: l)Toilets with urinals 2)Wash b a s i n 3)Wash b a s i n b a c k to original place 1:07 17 PROCEDURE DATA I Operation 14.)Draw o r p l a c e in temporary partitions 5)Move p a r t i ­ tion with toilets, urinals and basins. Sub-Total: 5k 9« A . D r a w o r p l a c e o f ­ fices and ladies' lavatory equip­ ment i n g e n e r a l area. B. Rearrange t h e following equip­ ment i n t h e given order: 1 ) A 1 1 equipment for both offices 2)Draw or place in temporary partitions II A c t Total 37 12 (CONTINUED) Think III A c t Total IV A c t Total Act Total k l 10 02 12 \ $ 2 $ 02 12 l:0i|. 10 03 13 17 27 03 13 01 01 02 02 01 01 12 3)Desk desk with 3 files 5) Desk 29 Sub-Total: k)Typewriter k l kk 15 03 18 10 25 03 18 56 15 ok 19 12 27 0k 19 PROCEDURE DATA I Operation 10* Act A . Draw or place b a l ­ ance o f p r o d u c ­ t i o n equipment (from 6-B-7) i n proper area. 33 B. R e a r r a n g e t h e following equip­ ment i n t h e given,order: 1) S h a p e r 2) P u n c h p r e s s 3) A r b o r p r e s s %) S l o - s p e e d D r i l l press 5) F o u n t a i n 6) H e l i - a r c Welder 7) D . C A r c Welder 8) H a c k s a w w i t h foreman s desk 9) D o - a l l B a n d saw 10) 1+ b e n c h e s 11) F o u n t a i n w i t h 2 welders and hack saw 5k Sub-Total: (CONTINUED) II Total Think 33 III IV Act Total Act Total Act Total 01 01 02 02 01 01 ^ 09 29 1 1:27 1 1 . Switch Basins, t o i l e t s , and urinals with partitions ±5 1:11+ 20 09 29 21 . 1+1 1:1+7 20 10 30 23 1+3 10 30 01 01 01 01 01 01 15 n PRODUCTION DATA (CONTINUED) I Operation 1 2 . Draw or place oper­ ators in p o s i t i o n . Act 01+ 1 3 . A. Draw a l l l i n e s in heavy. 1:27 B. Glue down a l l templets and permanent partitions• C Put models in place. D. Cut p a r t i t i o n s and doors from p l a s t i c and glue in p o s i t i o n . E. Rearrange the f o l ­ lowing equipment (with operators and stands) in the given order: 1) Rotabin with dial scale 2) Stock rack 3) 5 benches 4) Iii" D r i l l press 5) k benches 6) Small Engine lathe 7) Do-All Band saw with D r i l l press 8) Boring m i l l with Arbor press 9) Shaper with #3 Turret lathe II Total Oi^ Think Act III Total 01 01 10 10 Act 01 IV Total 01 Act Total 01 01 08 08 1:27 40 1+0 ko ko P R O D U C T I O N DATA. I Operation Act Precision Lathe with small LeBlond lathe 11) P u n c h p r e s s w i t h B&S #2 V e r t i c a l mill 2:37 Sub-Total: (CONTINUED) II Total Think 2:£2 15 4:19 15 Act III Total Act 02 17 20 12 27 IV Total Act Total 10) If.: 01+ 14• 15• 1:00 Construct bridge crane system from balsa wood, wire, and thumb-tacks; paint with tem­ pera; and i n s t a l l . P r i n t equipment nomenclature on drawing, 50 50 35 32 1:15 1:20 50 47 1:35 50 50 50 TOTAL TIMES: 19:47 = 14:45 = 7:07 = 17:42 = 19.78 14.75 Hours 7.11 Hours 17.70 Hours Hours 59 APPENDIX DATA EVALUATION SURVEY D AND COMPUTATIONS 60 DATA E V A L U A T I O N SURVEY In order t o complete data needed f o r a thesis on plant l a y o u t , i t is requested that you read the following i n s t r u c t i o n s and comply w i t h them t o t h e b e s t o f your a b i l i t y . Y o u r a s s i s t a n c e w i l l be g r e a t l y a p p r e c i a t e d . P o u r methods o f p l a n t l a y o u t t e c h n i q u e s a r e t o be evaluated: METHOD I. Drafting (Block Porm) II. Templets (Contour) III. IV. The following Models (Prototype) Templets and Models (Superimposed) c r i t e r i a w i l l be used f o r e v a l u a t i o n : A. Education level required to the layout perform B. Mental effort C. Space p e r c e p t i o n a n d u t i l i z a t i o n attained by layout engineer D. Decision influence r e q u i r e d t o do t h e l a y o u t EVALUATION (E) I. on management I n t h e space p r o v i d e d below, rank t h e e f f e c t i v e n e s s of " A " i n Methods I, I I , I I I , and I V by assigning the method i t best s a t i s f i e s w i t h a value o f " 1 0 " d e c r e a s i n g t h e v a l u e s o f t h e r e m a i n i n g m e t h o d s w i t h "0" a s t h e p o s s i b l e lower l i m i t . Repeat t h i s procedure with B, C , and D . Finish this section before reading I I . Best s a t i s f a c t i o n o f A a n d B would mean l e a s t r e q u i r e d Method II III IV EVALUATION A B D II. As a separate procedure, rank A , B, C , and D in o r d e r o f i m p o r t a n c e w i t h a t e n t a t i v e v a l u e o f "10" g i v e n t o 61 L A T A E V A L U A T I O N SURVEY/ (CONTINUED) the most i m p o r t a n t , and smaller values g i v e n the r e s t , a c ­ c o r d i n g t o t h e i r r e l a t i v e i m p o r t a n c e ("0" i s t h e l o w e r limit). Space is p r o v i d e d below. The most important e v a l u a t i o n w i l l b e t e r m e d E-]_, n e x t i m p o r t a n t E , e t c . C o m p a r e E-, w i t h E2 + E? + E L . I f En i s p r e f e r r e d o v e r t h e sum o f t h e o t h e r s , t h e v a l u e s s h o u l d b e a d j u s t e d s o t h a t E-,>Eo + Eo + E, . S i m i l a r l y , t h e v a l u e s w o u l d b e a d j u s t e d i r Ei ^ E2 + E^ + E. • H o w e v e r , i f E n < E + Eo + E. t h e n E-j_ s h o u l d b e f u r t h e r c o m p a r e d t o E2 * E3 o n l y f o l l o w i n g t h i s e x a c t p r o c e d u r e t o r e f i n e i t s v a l u e < , = , o r > t h e sum o f E + Eo# This step is repeated u n t i l a value - E is determined. T n e same p r o c e d u r e i s f o l l o w e d c o m p a r i n g E2 w i t h E~ + E> • R e a d j u s t m e n t s i n v a l u e s s h o u l d be f o l l o w e d a c c o r d i n g l y . * ^ 2 2 2 2 For example, the ranking might follow this action: A , most p r e f e r r e d , B, n e x t i n importance, C , n e x t , and D l a s t . A m i g h t b e v a l u e d 10; B , 7; C , j?; a n d D , 2; t e n t a t i v e l y . Upon comparison, A is not equal to or p r e f e r r e d over B + C + D , t h e r e f o r e , n o t o n l y does t h e combined w e i g h t o f B , C , a n d D e x c e e d A , b u t A m u s t b e c o m p a r e d t o B + C . H e r e we d e c i d e A = B + C . I f A = 10, t h e n B + C = 10. T h e r e f o r e , t h e v a l u e s f o r B a n d C a r e a d j u s t e d f r o m 7 a n d 5 t o 6 a n d ii r e s p e c t i v e l y . B I s e v a l u a t e d n e x t b y c o m p a r i n g w i t h C + D . I f B (6) i s d e c i d e d t o b e m o r e i m p o r t a n t t h a n C (ii) + D (2), t h e n t h e v a l u e o f D I s c h a n g e d t o 1. T h i s m a k e s B (6) g r e a t e r t h a n C + D (5) a n d d o e s n o t d i s t u r b t h e p r e v i o u s r e l a t i o n s h i p o f A (10) = B (6) + C (k) a n d A (10) < B (16) + C (1+) + D (1). EVALUATION fl CRITERIA (A,B,C, OR D ) TENTATIVE VALUE ASSIGNED FINAL VALUE ASSIGNED 62 DATA SURVEY SHEET I. M e t h o d CM) Evaluation (E) I (P II. II ) x j ( P III IV 7 10 8 2 ) J A 5 B i 1* 8 10 C 2 5 8 10 D k 6 9 10 Evaluation E l h 2 E Criteria Preference 3 = Z P J J C M J J ) 2 p i j ( M i n ) E il l P P = (2) (10) 1 1 E + = = Similarly, P 20 1 + Pinal Value Assigned C D 10 B 3 A 2 7 E + i2 2 P 1 2 E + 2 ' + ft)(7) + 2 8 = 61 = 10.5% = 118 = 20.3% = 187 = 32.1% = 216 = 37.1% E in n r 13 3 lij. 4 • ^ P , E + P E + (D(3) + (5)(2) + + 3 10 63 DATA SURVEY SHEET 2. I. E v a l u a t i o n (E) M e t h o d (M) I {p II. lj> II (p CP 2J> III IV 33> < V A 7 8 10 9 B 7 9 10 8 C k 5 10 10 D 5 6 9 10 Evaluation E 4 A Criteria Preference Pinal Value Assigned C D B 10 8 6 A 3 = lir-3 = 1 7 . 1 $ = 176 = 21.C >* = 262 = 3 1 . : \% = 255 = 30.5 '4 DATA SURVEY SHEET 3. I. EVALUATION (E) METHOD II I tt- II. IJ CM) .) FP 2 J III IV ) A 2 5 7 10 B it 5 8 10 C 2 k 8 10 D 7 8 9 10 EVALUATION PINAL VALUE ASSIGNED CRITERIA PREFERENCE 10 5 2 1 c A D B E^ SP L J FM ) I 2P. . CM ) = kQ = 86 = 2P. , C M _ ) = LI+1 T T 2P FM ) = 8.6$ 15.5$ = = 280 = 50. W 65 DATA SURVEY SHEET I*. I. Evaluation (E) Method I ( IIo (M) II III CP ) (P 2j V 3J IV ) A 10 10 10 10 B 10 10 10 10 C 2 7 5 10 D 2 7 5 10 Evaluation E l E 2 Criteria Preference Pinal , Value As s i g n e d D C B A .0 3 2 1 = 56 = 12.c = 121 = 27.< 2 p 2 P i j ( i j V CM ) i v = 95 = 22.0% = 160 = 37.C 66 DATA SURVEY SHEET 5. I. M e t h o d CM) Evaluation (E) I II III IV 5 7 9 10 B 6 9 10 C 8 9 10 7 9 10 V A D II. 3 Evaluation E Criteria Preference Pinal Value Assigned C 1.0 6 2 2 i E D A B 2 \ 2P i W 2P 2P = is*!* 78 = 12.9$ = 11+8 = 21+. 1 W ) = 180 = 29.7$ 2 P . .CM ) ij IV = 200 = 3 3 . 0 $ t J f t n i 67 DATA SURVEY; S H E E T 6. I* M e t h o d (M) Evaluation (E) I II CP ) 2 j II. III (p IV (p 3j> 4j> A 1 10 8 4 B 1 5 10 8 C 1 3 10 7 D 1 3 10 7 Evaluation E i E 3 Criteria Preference Pinal Value Assigned A D C B 10 8 6 1 K 2P l j = (M ) I 25 = 4.6% = 147 = 26.8% S P ijCM sp CM ij ) = 230 = 42.0% ) = 146 = 2 6 . 6 % I I T iv 68 DATA SURVEY SHEET 7. Io Evaluation (E) Method I (M) I I III IV io 5 10 10 8 10 8 io (p ) 2j II. A. 0 B 0 C 0 D 0 5 5 Evaluation E E Criteria Preference 10 8 2 1 D C A B l 2 E3 E Pinal Value Assigned k S P . . (M_) ij I 2P (M ) l j I I 0 = = 105 0% = 21.9 $ = 174 = 36.3 = 200 = 1+1.7$ 69 DATA SURVEY SHEET 8. I. Evaluation Method (E) i II V II. (M) III IV CP..) A 5 7 10 9 B 2 6 10 8 C 3 3 10 6 D k 10 8 Evaluation E i E 2 P i n a l Val ue Assigned Criteria Preference Eo 4 2P. ij 2p ij J ! (M ) III T T T CM i v)' c 10 D B A 2 1 7 = 67 = = 77 = 1 6 . 1 % = 200 = 41.7% = = 2802% 135 DATA SURVEY I. SHEET Evaluation (E) Method I II CP II. (M) III IV ) A 0 6 8 10 B 0 5 7 9 C 2 9 10 D 1 9 10 Evaluation E i E 2 E 3 E k Criteria Preference Pinal Value Assigned c 10 D B A 2 p . . ( 2 sp M l ) W l y Cm ) in' 2P..(M ij ) IV 8 5 3 = 28 = 4.5$ = 1 1 5 = 18.6$ = 221 = 3 5 . 7 $ = = 111 255 .2$ 71 DATA SURVEY SHEET 10. I. Ev ,luation ( E ) Method (M) 8 II I fp II. 1 3 ) IV III CP ) CP3j) 2 j A 10 8 6 B 8 6 10 C 4 5 7 10 D 7 8 9 10 Evaluation Criteria Preference i % E Pinal Value A s s ig n e d C A D B 2 < s 2P Z 2 M V i j } i (M ) n M *iJ< III> P i J C V 10 8 5 3 1 7 9 =24.3% = = 172 = 4 4 = 23.3% 1 9 3 == 26.1% = 194 =2 6 . 3 % 72 D A T A SURVEY" SHEET 11. I. M e t h o d (M) Evaluation (E) i CP,.) II. A 2 B 3 C 3 D 3 Evaluation E III I I (p 3 6 ( M 5 10 6 10 8 10 8 10 c 10 6 4 2 Eo U 4j> Pinal Value Assigned D B A P (P 3j> Criteria Preference i 2 IV I I > = 64 = 13.1% = 97 = 19.8% = 138 = 28.2% = 1 9 0 = 38o 9% 73 DATA SURVEY SHEET 12. I. Evaluation Method (E) (M) II III CP ) < 3J> I P 2 j A 3 B 3 C D II. E E E 5 8 k 5 8 5 10 10 10 10 5 Evaluation Pinal Value Assigned Criteria Preference 10 10 5 5 c D B A l 2 3 i SP^CM.) ij II IV = 120 = 15.2$ = ll+O = 1 7 . 7 $ = 250 = 31.6$ = 280 = 25.4$ 74 DATA SURVEY SHEET 13. Io Method Evaluation (E) I (M) II III (P ) ( 3j> 10 k 3 5 8 10 6 9 10 2 j A 8 B 2 C D II• E l E 2 E 3 E k p 8 Evaluation = ^ i j ^ I I I 2 p ijt iv> M 10 9 k k = 106 = ) 5 194 242 13*7% = 25.2% = 229 = = 10 Pinal Value Assigned D C B A I p ( 4j 10 Criteria Preference 2P^(M ij IV 29.7$ = 31.k% } 75 DATA SURVEY SHEET Ik. I. Evaluation (E) Method I A B II f V V III II• E 10 9 5 7 10 8 8 10 9 10 l 4 Criteria Preference D C B A i 2 E3 \ = 2 p 1 J C M i n i^ iv) M 7 3 2 59 = 1 0 . 3 % ) = 1 9 6 = 34.2% = 2 1 2 = 37.0% } Pinal Value Assigned 10 = 1 0 6 = 18.5% 2P..CM,,) ^ ^ 5 Evaluation E fp 'V C D IV Lo f (M) APPENDIX .MPLE E CALCULATIONS 77 SAMPLE BARTLETT'S S a m p l e S i z e = ru = CALCULATIONS TEST OF s 1[|_ FOR EQUAL = i VARIANCES u n b i a s e d e s t i m a t e s t a n d a r d Zn ± Number o f B a r t l e t t ! = N t h e = 5 6 s a m p l e s s o f d e v i a t i o n T e s t = i s K = 4 s h o w n I I S I I I 5 8 5 . 7 8 S I V 5 8 6 . 6 6 « 3 . 8 7 b y : f F S 2 M = f - ^ b - M ) M w h e r e s^ 2 = = t h e CN-K) I n v a r i a n c e s o f 2 p t h e - 2 = * P 2 •)->-> U i 1 1 I n s a m p l e ; s^J the p o o l e d v a r i a n c e z 2(n -l)s ± [ f n j - 1 ) ± = N - K = 1 3 ( 3 5 . 8 8 + 1 4 . 9 8 + 3 3 . 4 1 + ¥ + . 3 5 ) 5 6 - 4 = I n 3 2 . 1 5 = 3 2 , 1 5 3 . 4 4 I n 3 5 . 8 8 = 3 . 5 8 I n 1 4 . 9 8 = 2 . 7 1 I n 3 3 . 4 1 - 3 . 5 1 I n 4 4 . 3 5 = 3 . 7 9 = 1 3 o 5 9 2 1 n M = = 5 2 ( 3 . 4 4 ) 2 . 1 7 - 1 3 ( 1 3 . 5 9 ) 2 S i 78 A =3(K1-1) ' i-1/ \ N1-K 1 ~ 4 1 = 0.0321 (3)(3) 13 52 _ = k-1 = 3 K+ _5 = ij.868,5 (0.032)2 n f 1 1 b = f2 1 - A +i 4868.5 = 5027.9 1 - 0.0321 4+8168.5 fM = (4868.5)(2.17) (3)(5027.9 - 2.17) t ± 2(b-M) = 0.701 At 5% level of significance, I? , = 2.60 (3, 4.060.3) 0/0 X s SAMPLE CALCULATO INS FOR STUDENTS' t DS I TRB I UTO IN Meh tod II III H.55 31.86 21.21 5.99 5.78 3.87 2 =• 8P IV 35.34 6.66 N-K Students' t = 1+1 l 2 = 14; N = 28; K = 2; Degrees of rfeedom (d.f.) = n^_ + n^ - 2 = 26 For meh tods III and IV: 13 [(5.78) + (6.66)] 24 t = 35.34 - 31.86 1.48 (1 1 Ilk n n n ± 2 6.24 2 + Ik At d.f. = 26, t ^ = 1,71 For meh tods I and II, 13fc5o99) + C3.87)J 26 = 5.11 s 2 2 80 t = 21.21 5.ii At d f . = 26, e = 1.71 11.55 1 1 + Ik lk = 5.07 BIBLIOGRAPHY 82 BIBLIOGRAPHY Literature Cited 1. United States Bureau o f t h e Census, S t a t i s t i c a l A b s t r a c t o f t h e U n i t e d S t a t e s : 1951, 7 1 + t h ~ e d i t i o n . W a s h i n g t o n , D . C . , 1951* P P . 742-743* 2. Mogensen, A l l a n H . , "What's Happening t o P l a n t L a v o u t , " F a c t o r y M a n a g e m e n t a n d M a i n t e n a n c e , 91:175-178, M a y , 1^33. 3. A p p l e , James M a c G r e g o r , P l a n t L a y o u t a n d M a t e r i a l s H a n d l i n g , N e w Y o r k , T h e R o n a l d P r e s s C o . , 1950, p p . 26-31. k* Ibid., p. 5. I b i d . , p p . 227-228. 6. "Templets; Technique Developed f o r P l a n t L a y o u t , " M a c h i n e D e s i g n , 19:113* D e c e m b e r , 1947. G r i d l e y , G . C . , " U s i n g a Combination o f Methods t o Get E f f e c t i v e L a y o u t , F a c t o r y Management a n d M a i n t e n a n c e , 106:120-121, J u n e , 192+8. 7« 258. 1 1 8. Parrett, Robert E . , "Preparation o f Layouts Aided by P h o t o s t a t i n g , " FF aacct to r v ^ M a n a g e m e n t a n d M a i n t e n a n c e , 106:70-71, N o v e m b e r 9. B a r t l e t t , R . F . , "Photographs o f Scale Model L a y o u t S i m p l i f y P l a n t C h a n g e s , " F a c t o r y Management a n d M a i n t e n a n c e , 104:142-144, N o v e m b e r , 1 9 1 + 6 . 10. P a r k s , C h a r l e s H . , " D i s a p p e a r i n g Boards Show P l a n t L a y o u t i n S e c t i o n s , " F a c t o r y Management a n d M a i n t e n a n c e , 105:81, D e c e m b e r , 1947. 11. B r i n k e r h o f f , H . W . , "Three-Dimensional Drawings A i d Plant Layout V i s u a l i z a t i o n , " Chemical I n d u s t r i e s , 56:410-411, M a r c h , 1945« " 12. " T o yLayouts f o r L i f e Size Planning," Mill and F a c t o r y , 37:91-94*216,220, J u l y , lWFl 83 13. 14# P i o c h , W i l l i a m P . , " P l a n t Model Insures Success i n L a y o u t C h a n g e s , " F a c t o r y Management a n d M a i n t e n a n c e , 105:130-132, J u l y , 1947• M a l l i c k , R . W. a n d J . H . S a n s o n e t t i , "Templet o r Models f o r P l a n t L a y o u t , " A m e r i c a n M a c h i n e s t , 90:101-104. A u g u s t 15, 1946• 15. Y i n g l i n g , S . A . , " S h o r t O r d e r Shops Save Time i n D e v e l o p m e n t P r o j e c t s , " M a c h i n e r y , 60:191-193* S e p t e m b e r , 1953. 16. C o l v i n , Fred H . and Prank A . Stanley, Running a Machine S h o p , New Y o r k , T h e M c G r a w - H i l l Book C o m p a n y , I n c . , 1941, V* 3k* 17• S t e v e n s , S . S . , e d i t o r , Handbook o f Experimental P s y c h o l o g y , New Y o r k , J o h n W i l e y a n d S o n s , I n c . , 1951, p p . 613-678. 18. McGeoch, J o h n A . , T h e P s y c h o l o g y o f Human L e a r n i n g , 2 19. N e w Y o r k , L o n g m a n s , G r e e n a r i d C o m p a n y , 194« E l l i o t , T . A . andE . I. Denenberg, Industrial Engin­ eering Study o f the Engineering^Experiment Station Machine Shop, Being published a t time o f w r i t i n g , ( M a y - J u n e , 1954), E n g i n e e r i n g E x p e r i m e n t S t a t i o n o f the Georgia I n s t i t u t e o f Technology, A t l a n t a , G e o r g i a . 20« Churchman, C . West a n d R u s s e l l L . A c k o f f , " A n A p p r o x i m a t e Measure o f V a l u e , " Short Course i n Operations R e s e a r c h , C a s e I n s t i t u t e o f T e c h n o l o g y , J u n e , 1953, p p . A M V ; 1-14. 21. Dixon, W i l f r i d J . and Prank J . Massey, J r . , Introduction t o S t a t i s t i c a l A n a l y s i s , New Y o r k , T h e M c G r a w - H i l l B o o k C o m p a n y , I n c . , 1951, P » 90. 22 I b i d . , p p . 94-H0. 23• P l a n t L a y o u t T e m p l e t s a n d M o d e l s , New Y o r k . A m e r i c a n S o c i e t y o f M e c h a n i c a l E n g i n e e r s , 1949« # 8k Other References A l f o r d , L e o n P . a n d J o h n R . B a n g s , e d i t o r s , P r o d u c t i o TIn H a n d b o o k , N e w Y o r k , T h e R o n a l d P r e s s C o m p a n y , 194 « B a i r d , Dwight G . , "Scale Models—How K a i s e r - F r a z e r Saves T i m e I n P r o d u c t i o n P l a n n i n g , " A m e r i c a n B u s i n e s s , 21:16-17, August, 1951. B e l l , LO J . , " L o w C o s t M o d e l s f o r P l a n t L a y o u t , " M a c h i n e s t , 91 :LLI|.-LL6, F e b r u a r y 1 3 , 1 9 4 7 . American Boyce, C a r r o l l W . , "Adopt Best i n Plant L a y o u t , " Factory M a n a g e m e n t a n d M a i n t e n a n c e , 107:66-87, S e p t e m b e r , 1949• " S c a l e Model Guides F o u r - S t e p P l a n t B u i l d i n g R e p l a c e m e n t , " F a c t o r y Management a n d M a i n t e n a n c e , 107:84-86, M a y , 1949. C l e m e n t , E . J « , " P l a n n i n g L a y o u t o f Medium S i z e d P l a n t , " M i l l a n d F a c t o r y , 37:108-109,280,284,286, A u g u s t , 1 9 4 5 * D a s e y , Homer H . , " S a v e T i m e , Money W i t h T h r e e - D i m e n s i o n a l P l a n n i n g , " I r o n A g e , 168:133-135, N o v e m b e r 8 , 1 9 5 1 . E a t o n , Kenneth T . , "Space Management—The F o u r t h M a n a g e m e n t R e v i e w , 41:236-237, A p r i l , 1 9 5 2 . "Factories Dimension," i n M i n i a t u r e , " F o r t u n e , 41:97-100, M a r c h , 1 9 5 0 . Immer, John R . , L a y o u t P l a n n i n g Techniques, New Y o r k , The M c G r a w - H i l l B o o k C o m p a n y , I n c . , 1950. Ireson, William Grant, Factory Planning and Plant N e w Y o r k , P r e n t i c e - H a l l , I n c . , 1952. K e l l o g , E . Cm " P l a n t L a y o u t ; T h r e e D i m e n s i o n s I r o n A g e , 171:75-76, M a r c h 19, 1 9 5 3 . 9 " L a y o u t K i t Makes B l a c k a n d W h i t e P r i n t s B u s i n e s s , 21:59, J a n u a r y , 1 9 5 L Help," of Plans," M a l l i c k , Randolph W. andArmand T . Gaudreau, P l a n t New Y o r k , J o h n W i l e y a n d S o n s , I n c . , 1 9 5 L " M o d e l P l a n t s i n Mass P r o d u c t i o n , " N o v e m b e r 5, 1949. Layout, American Layout, B u s i n e s s W e e k , p p . 41-4 , "Model S h o p - L a y o u t s , " A i r c r a f t Production, April, 1947. 2 9:142-144, 85 Mogensen, A l l a n H . , " P l a n t L a y o u t , " F a c t o r y Management a n d M a i n t e n a n c e , 91 . ' S u p p l e m e n t , 214.6-260, M a y , 1 9 3 6 . P a t t o n , ¥ . G . , " P l a n t Models P r o v i d e Continuing Production A i d , " I r o n A g e , 166:72-73, N o v e m b e r 23, 1950. Richroath, G .A . , "Plant Layout andFacilities f o r Precision M a n u f a c t u r i n g , " T o o l E n g i n e e r , 26:32-35* A p r i l , 1951. R o s s , G i l b e r t I . , "Three Basic Steps t o Good P l a n t L a y o u t , " T h e P l a n t , 6:55-57* J u l y , 1952. Rowley, G . S . , "Section Layout Board Permits Quick Changes," F a c t o r y M a n a g e m e n t a n d M a i n t e n a n c e , 101:89, O c t o b e r , 1943. " S c a l e Model Helps P l a n M u l t i - S t o r y H a n d l i n g , " F a c t o r y M a n a g e m e n t a n d M a i n t e n a n c e , 105:74-75* J u n e , 19477 " S c a l e M o d e l L a y o u t P r e v e n t s Bugs i n A s s e m b l y , " F a c t o r y M a n a g e m e n t a n d M a i n t e n a n c e , 106:82-83, M a r c h , 191+tf. " S c a l e Model Speeds K a i s e r - F r a z e r C o n v e r s i o n , " F a c t o r y M a n a g e m e n t a n d M a i n t e n a n c e , 104:116-117, M a y , 19/4.6. S h u b i n , John A . and H u x l e y Madeheim, P l a n t L a y o u t , New Y o r k , P r e n t i c e - H a l l , I n c . , 1951. Spurgin, Robert J r . , "Planning Plant Layout," Iron Age, 158:73-75* D e c e m b e r 1 9 , 1946. Thuering, G . L . , "How to G e tF a s t e r , Better, Less Expensive Plant Layout Drawings Without D r a f t i n g , " Factory M a n a g e m e n t a n d M a i n t e n a n c e , 110:88-89, O c t o b e r , 1952. Wheeler, W i l l i a m S . , "Scale Models Help V i s u a l i z e Production J o b , " F a c t o r y M a n a g e m e n t a n d M a i n t e n a n c e , 105:74-77* D e c e m b e r , 1947« , " S e c t i o n a l Scale Model W i t h Complete Color Code," F a c t o r y M a n a g e m e n t a n d M a i n t e n a n c e , 106:104-105, O c t o b e r , 1948.