Lecture 8 on Work Measurement Techniques PDF

 Lecture 8 T!me Study · what are the work measurement techn!ques ? > T!me Study - > Standard data - >...

 Lecture 8 T!me Study · what are the work measurement techn!ques ? > T!me Study - > Standard data - > T!me formulas - -Fundamental mot!on data -work Sampl!ng what Measurement ? · s work > - Object!ve data dr!ven , process for establ!sh!ng t me staddds what does work measurement uses ? > - plann!ng > - compar!ng alternat!ve work methods > determ!n!ng capac!ty - -just!fy purchase of new equ!pment > develop - pay system T!me Standards What s t!me standards ? · > - Appropr!ate and reasonable amount of t!me to perform a spec!f!c work task * Based on fa!r day's work : amount of work that ca be produced by a qual!f!ed employee when work!ng at a normal pace and effect!vely ut!l!z!ng h s t!me where work s not restr!cted by process l!m!tat!ons. Calculat!ng t!me stadods · T!me Standard = Work Content X Perfrat!ng X(1 + PFD) T!me · What s work content ? > - The amount of work conta!ned n a product or process , !n person-h!s or mach!ne h s what s total job t!me ? · i i i i i i i i i What · are t!me study procedural requ!rements ? > - standard!zed method n place > Prof!c!ent - operator > Preparat!on - > knowledgeable analyst - what the t!me study equ!pments? · are -Stopwatch -Cl!pboard -T!mestudy form -Calculator What the t!mestudy preparat!on dec!s!ons? · are > Stopwatch operat!on - - Snapback > cont nuous - -Def!ne elements > - Determ ne work cucles · How to measure work Content ? tobserve job d!v!de, !nto elements w th stat and stop po!nts Cons!der wh!le def!n!ng work elements > Cohes!ve groups of therbl!gs - - As f!ne as needed - Def!n!te stat and stop po!nts Stop for - element! s start for element ty - Repeated necessary -Separate mach ne and work elements -Separate constant advar able elements -Ass!gn labels and record n sequence on t!me study form i i i i i i i i i How ? many cucles to study 130 e2 1230- t · n = [] t- students 5- sample + stat!st!c staded dev k + tolarance * - sample mean Quest!on n =) poux 38 3. = 39 cucle to study Quest!on + = 2. 262 = Soydan 1. 2 sen ↑ = [222x 37  conduct!on T!me Study Enter descr!pt!on job Enter elements · keep track of t me from beg nn ng to end , > here ,!f cont nuous - W : Watch read!ng - OT : Observed element t me > NT : normal t!me - Rate the · operator - element by element , observat!on by observat on Tavg rat!ng for each element > for - whole perf. what the record!ng problems ? · are -Fore!gn element : unnecessary , non-product!ve - can be measured , mark n NT column -If too short t!me !nclude , n elemental t me , c rcle to des!gnate as w!ld - m!ssed element : Analust's error - des!gnate w th M n W column - Out of sequence element toperator var es order > lack of tra!n!ng - i i i i i i i i i i i i i  conclud!ng a T!me Study Record f!n!sh!ng t!me · · Prov!de operator w th perf rat!ng Calculate OT (cont!nuous used · Complete Summary · - #of obs. Per element - !ncorporate Perf Rat!ng n Summary f not done obs. by obs. > - % Allowance - extra t me > three - categor!es Us!ng staded t me to Determ!ne Operator Eff!c!ency Eff!c!ency = 100 X staded has eoned Hrs on Clock Quest!on 36 33 x8 cycles. = 290 64 m n. Eff!c!ency * = 100 29p 64. = 121 1 %. 240 cucle t!me" 36 33 m ns. What are the other needs or tupes of stadods ? Temporary · standards > operator s learn!ng - Apply when - Spec!fy upper l!m!t · Set up stadods > - d!str!bute t!me across product!on t!me + treat separately Part!al · set up What are the adjustments to Measured T mes from T!me Study > - Perf rat!ng > learn!ng curves - t nd v dual d!ff > Allowance - + personal - fat!gue + delay i i i i i i i i i i i i Performace Rat!ng Normal T me = Perf rat!ng X Observed T!me Accounts for d!fferences between adw th n operators Cr!t!cal element of t me study Subject!ve Requ!res clear def of 'normal' operator what are the d!fferences between operators ? V ~ Work Related Personal - tra!n!ng -strength * - exper ence coord!nat!on - Sk ll -!ntell!gence > - v s on > apt!tude - > - att!tude What are the charachter!st!cs of a sound system? > - Accurate , cons stent > Easy to use - keyed > - to benchmarks When to use sound susten? study for > Dur!ng - t me > elemental rat!ng - - longer aycles , tasks -mach!ne t me rat!ng = 100 toverall rat!ng > - short cycle repet t ve tasks What are the rat!ng systems ? -West!nghouse - sk ll , effort cond t ons , , cons!stency * Sunthet!c - based on fundamental mot on t!mes + P = Expected t!me/observed t!me > - Speed rat!ng > - focus on work rate i i i i i i i i i i i i i i i i i > - Object!ve rat!ng -judge pace relat ve to bachmark task , then mod!fy for d!ff!culty West!nghouse System · Once each factor rated Sum the four values to g!ve allowance n% Or add to 1 to g!ve performance factor Best for whole job not !nd!v!dual elements · , Allowances The need for allowances : -Normal t me s st!ll deal zed , best case scenar o account!ng for > No nterrept ons problems breaks, etc - , , Allowance m!ght be appl ed to : - total cucle t me - personal needs delaus , workstat on clean up , m nor mach ne ma ntenance - mach ne t me only ~ tool ma ntenace, power var ence > - effor t me only -fat!gue , unavo dable delays i i i i i i i i i i i i i i i i i i i i i  Determ ned through -product!on study -work sampl!ng What the types of fat!que ? · are - constant ~ personal-apl ed to total cucle t me -bas!c fat!que apl ed - to total cucle t me -Var!able -var!able fat!que -unavo!dable delays-superv!sor talk mach ne nterference,.. , -extra allowances · var able mater!al qual!ty clean and o l mach ne - to mach ne t me - shutdown ad tool ma!ntace-apply " pol!cy allowances -new employee l!ght duty , · What s the Personal Allowance(P) > Restroom and water break - > Affected by env!ronmental cond!t!ons (heat , cold) - + - 5% typ!cal What s fat!que allowances (F) : > Bas c - > - accounts for var!ab!l!ty n work pace - 4% s typ!cal for l!ght work > - Var!able > - less than opt!mal work cond!t!ons stress a worker phys!olog!cally Psycholog!cally , , or both ways > cond!t!ons - nclude : > heavy l!ft!ng - -h!gh (RA (AH/40-1) 100 * card ovascular demad = - h!gh mental demands h!gh v sual demands + cond t ons poor sensory Th!gh phys!call stress "monotonous or ted ous work i i i i i i i i i i i i i i i i i i i i i i i  - Allowances for Unavo!dable Delays (D) Factors that !mpede (engel) operator effort : > !nterrupt!ons from superv sor, eng neer, etc - problems w th tolarances , spec!f!cat!ons ; mater als + -mach!ne !nterference Unavo!dable Delay Due to Mult!ple Mach ne Interference Mach ne !nterference t me = 1X mean serv ce t me % Allowance = mach ne !nterference t!me t me ( mach ne run + serv ceo Stand T!me/Prod Un!t ·.. = Imach!ne run t me + serv ce t me + mach ne !nterference t!me product!on un ts per run t me or Imach!ne = run t me + serv ce t!me) X(1 + allowance) product!on un ts per run t me Quest!on > - meanserv!ce un!ts per run t me EXI ↳ product!on N16 1 = 20 % mach!ne !nterference t!me = 20 % X10 m ns = 2 0m n. sand t!me/prod Un!t 150 2 32 4 m nlun t +. = 10 + =. 2 4100 1 25 % %. Allowance = =. (150 + 10) i i i i i i i i i i i i i i i i i i i i i i i i i i i i Other Allowances Attent on t me allowaces · > - mach ne run t me methods must match stadods - > conduct per!od!c aud!ts - - compl!ance > Operators - > superv!sor - -analyst Learn!ng Curve Pract!ce affects performance · Sk!lls mprove w th pract!ce Learn!ng curves quat!fy decrease n task performance t me , as funct!on of task repet t on Theory : as total quant!ty produced doubles t melun t decl!nes at , a constant rate (expressed as percentage) i i i i i i i i i i i i i i i i i i i i i i i i i What · are the Charachter!st!c Equat!on of Lean!ng Curve total un ts produced * eyx = kX or logYx = logk + Nlog X c t!meto produce N" = exponent V f!rst un t pred!cted tand lagle from log-log plot of data) = prodt meme un t · 2N = rate Quest!on 2 = 0. 82 enlog!o = log100. 82 +n = -0. 2863 Yx = kX - 0. 2863 45 = 94X 0 2863 45/au 10g10(45/94) -. = y + = - 0 286310g10X. X 1 1174. = log!o 1 1174. 10 - 13. 1 = X cycles Quest!on Determ!ne by calculat!ng the area under the lean!ng curve : * + [Yx )k[(X2 Ye)" = + - (X - Y2) 3/In + 1) > - Total t me ↓ ↓ ↓ ↓ exponent that represents the me tuher slope of the lean!ng curve 1 0 2863 + 1 2863 + gu((13 - 0 (1-0 2863). -. = + (2) - (1 - ). = 768m!ns product!on t me i i i i i i  Quest!on 768 m!ns/13 cucles = 58 6 m nkucle. Quest!on 2" = 0 93. nlog!o 2 = 10g100. 93 + n = - 0 1047. Yx = 4X 1047 30X0. 20 = 0 1047 20/30 y. = log(20/30) = -0. 1047log!o X 1. 682 log!o X > X = 48 1 - =. Quest!on * k((Xc + yz)" 3/(n * [YX = - (x - yz) + 1) 1) 1-0 1047 +/ + -(101047. = 30 ((48 + (2) - (1 - = 1065 9 m ns. ( - 0 1047. + 1) Learn!ng Rem!ss!on · Perf decrement due to t me away from task Amount of rem ss on s a funct!on of locat!on on the learn!ng curve pr!or to !nterrupt!on (] #of cycles · Pred!ct!on of t me to produce f!rst un t after !nterrupt!on completethef!rst un t produced upa return from break 3x = 1 + t!me for f rst ↓ cycle # of cycles to reach send t!me i i i i i i i i i i  Quest!on /(au-uz(-1)) 0.2863 -Bu s - !f no break occured 3 m!nsx = 33 5 m ns , 47 + 34 y = =.. Now 11 cucle !s the new f!rst cucle of new learn!ng curve 0 2863 4x (53 3)x -. =. Unavo!dable Delay : Mult!ple Mach!ne Interference Alternat!ve suggest!on when N6 · C = T! + T2 + T3 T tmach ne runt!me/cycle k = Tat s attent on percycle/mach!ne Ege s lost product!on t!me due to nterference C + Cucle t me Quest!on when N16 I=9 5. % mach ne !nterference t!me = 0 095X5. = 0. US Stand t!me/prod un t = (150 + 5 + 0. 48)/Jun!ts = 31. 1 un!t % Allowance = [0 48/(150 5)] x 100. + = 0 31 %. When N2, 6 50([ X-jumber of mach!nes/opat sen I = + ~ mach!nerunt!me MI = Interference & as % attent on t me i i i i i i i i i i i i  Quest!on MRT = 150 1 = 502[(1 + 30-+ 10]" (1 + 30-!!)3 MAT = S I = 2510 % N = 55 ; X = MRT/MAT = 30 25 1x5 m ns. = 125 5 m ns. = mach!ne !nterference t!me Stadt!me/Produn!t (150 + 5 + = 125. 5) /55 un ts = 5 1 m!nlun!t. 1 Allowace [125 5 /(150 +1) ] X 100 80 97% % =. =. MOST what are the alternat!ves to T me Study ? · - staded elemental data > Formula construct on - - predeterm!ned t me sustems -Work sampl ng · what s Predeterm!ned T!me Systems? - standard data systems for determ!n!ng stadad t mes for bas c elements of work > appl!cable to w de var!ety of manual tasks products and process - , -aka bas c mot on t mes , synthet!c t mes - some systems > Method T!me Measurement (MTM) - - Maynod Operat!on Sequence Techn!que (MOST) -Modular Arrangement of Predeterm!ned T me Systems (MODAPTS) i i i i i i i i i i i i i i i i  ? · why we use predeterm!ned t me systems > Develop effect!ve method pr!or to product!on - > mprove current methods/explore alternat ves - -set t me standards > est mate product!on capac!ty - "select!ng effect!ve tools and equ!pment > produce accurate job descr!pt!ons for tra!n!ng - > n t me stadeds and - mproved cons!stency est mat ons > el m nate perf rat!ng - - update t!me staded after method changes How to predeterm!ned T!me Sustens ? · use > Select - job > Analyze elements ; record appropr!ate chart - work on > Record d!stances , parts and tool we!ghts other !nfo requ!red by system - , > system's for - Use table to determ ne NT each element -Sum elemental t mes , apply PFD allowances and result s ST est mate * most of the systems are propr!etary Systems d!ffer n > levels deta ls - on > Types of elements addressed - work > - Spec!al cond t ons -body part > - d!stance travelled -res!stance we!ght , - others -Appl!cat!on rules => Tables of t!mes for each element/cond!t!on What are the tupes of predeterm!ned T!me Systems - V ~ Average mot!on Add!t!ve - typ!cal work task performed > - Bas!c t!me + extraord!nary t me under tup!cal cond t ons requ!re -Work-Factor typ!cal amounts of t!me > MTM MOST , MODAPTS - , i i i i i i i i i i i i i i i i i i i i i i i  Methods T!me Measurement (MTM) Performed m cromot ons on dr ll press operat!ons Found data to be appl!cable toall classes of work !nvolv!ng maual mot!ons" L!m!tat!ons e appl!cable when mot on t me s not !nfluenced by process Cons!derat!ons · > d!stance , tupes of reach , we!ght of objects moved prec!s!on , body posture - , and body part n mot on Vers ons · > - - 1 + most deta led cecler cal tasks -2- less deta led ; effort port!on of work cucle (m!n Mtwork!ng w!th m!croscope - > 3- st!ll less deta!l HC +health care - > -v - metal cutt!ng/mach!ne stop - ADAM : Computer system based on MTM t mes MOST What s MOST ? · > - A predeterm!ned t me system -Based Upon MTM-1 and MTM-2 - Less deta!led > Faster thanMTM-1 - What are the appl!cat!ons of Most ? > short cucle repet!t!ve tasks , to long , complex - tasks ; -off!ce work warehous!ng , , mater al handl!ng !ndustr!al , assembly,... What are three vers ons of MOST ? - ~ V Bas!c MOST Max!-Most M!n!-Most > - core of MOST system > - least deta!led - most deta!led - - > - for most !ndustr!al work operat!on occur less the 150 t!mes/wk operat!ons h!ghly > t!mes/wk - 2 repet!t!ve - operat!on recurs 150-1500 m ns > - up to 10m!ns -> 41. 6m n work s def!ned and descr!bed as the movement of objects (w = Fd) Spec!f!c stadod!ced sequences of · movement v. bas c mot on assessment Pr!mary un ts of work are fundamental act v t es ( collect!on of bas c mot ons). Cond!t!on affect durat!on of sequences T!me assessment based on 'aug sk lled operators' work!ng at on 'aug perf level' or' normal pace'.. · TMU[1 t!me measurement un!t TMU = 0. 00001h] i i i i i i i i i i i i i i i i i i i i i i i i i i i i i  What are the Most Sequence Model ? -General move > - Controlled move > Tool use - - Manual Crane What s General more ? tunrestr cted movement of object through a r What are the subact!v!ty sequence of General Movement ? 1) reach 2) ga!n manual control 3) move object Get(1 , 2).... Put (3 u) ,... Return (5) 4) place obj S)return (mostly hor!zontal > - D!Act!on D!stance + B: Body mot on (mostly vert!cal - G : Ga n control + p : placement + # : !ndex value of the parameter Parameter Index!ng - character!ze the move · > 1) what moved ? - s be!ng 2) If tool , what k nd ? Is t used ? > - > - 3) How s !tem moved ? If tem s not tool that s used , and travel s unrestr cted , then General Move sequence s appropr ate -4) what does operator do to get object ? to determ!ne ndex values for ABG -!) What does operator do to put object ? to determ!ne ndex values for ABP -6) Does operator return or clear hands ? · And for method analus!s , be!n w th + 7) Is th s to do the ? act!v!ty necessary job i i i i i i i i i i i i i i i i i i i i  Quest!on l!ghtwe!ght port freely , no obstruct on > - general move S gets w!th reach A no body mot on Bo l!ght object GI Total TMu = (1 +0+ 1 + 1) + 6 + 1 + 16)x10 put 10 steps away Ald bend down to pallet B6 = 410 put no throw, PI no adjust Total seconds = 410/27. 8 = 14 75. Al6 yes 10 steps , D! Bo G! Ald Bo Pr A16 put return get i i  Quest!on what does operator get ? small object How does operator moxe? general move & what does operator do to get ? walks 8 steps Al6 goes through doorway B16 p!cks up small object G1 what does operator do to put ? Total TMU = (16 + 16 + 1 + 1 + 6 + 1 + 0) x10 = 410 puts wh t n reach Al Bend down to floor B6 Total seconds = 14 75. adjust P put no throw , Returns ? No Ald Beo G! A! Bo Pe Do put return get Quest!on = G3 Do e(1 1)xb] A! Bo AlBoP 3 + (1 + 160 TMUS + + 10 = return get Quest!on A! Bo Gy Al Bo Pr Do put return get [1 + 3+ (1 + 1)x6]x 3x10 = 480TMUS i i  · what s controlled move ? - Object movement path s def!ned or restr!cted · What are the subact!v!ty sequence of Controlled path 1) reach 2) ga!n movement 3) move object 4) allow t me to process to occur sall!gn object follow!ng controlled move or at conclus on of process 6) return A B G M X I A get all!gn or return actuate A : Act on d!stance (mostly hor!zontal) B: Body mot on G : Ga n Control M : Move controlled X : Process t!me I : Al!gnment · When controlled move occurs ? 1) Object s restra!ned by attachment to another object 2) Controlled dur!ng move bu contact w th surface 3) Moved along controlled path to accompl sh act!v!ty Parameter Index!ng character!ze the move · > 1) what moved ? - s be!ng 2) If tool , what k nd ? Is t used ? > - > - 3) How s !tem moved ? If tem s not tool that s used , and travel s restr cted , then Controlled Move sequence s appropr ate -4) what does operator do to get object ? to determ!ne ndex values for ABG + 5) What does operator do to move or actuate object ? to determ!ne ndex values for MX1 (Move !mpl!es Mand I nvolved :actuate nvolves Mand X !nvolved ( -6) Does operator return or clear hands ? · And for method analus!s , be!n w th + 7) Is th s to do the ? act!v!ty necessary job i i i i i i i i i i i i i i i i i i i i i i i i i i i  Quest!on what s be!ng moved ? several ports How s tem moved ? Controlled movement & What does operator do to get ? reachs several ports Al Bo no body mot on Collect several Gy What do to all!gn or actuate ? (1 + 0 + 3+ 3 +o + o+ o X10 = 70 TMU sweep!ng mot!on Ma No process t!me Xo 10 Return ? No Do i i i i  Quest!on vazgeçmek > sum - of two stages & What does operator do to get ? reachs several ports Al Bo no body mot on l!ght object G What do to all!gn or actuate ? (2 6) X0 + = SO THUS Two stages MG No process t!me Xo 10 Return ? No Do Quest!on 3 reach A none Bo Heavy object Gy TMu = (1 + 3 + 3)x10 = 70 pushes Mz(12) no process t!me Xo Io Ag....... i  Quest!on What s moved ? Pedal How moved ? Bu foot + controlled move What do to get ? & w!th!n reach Al none Bo l!ght object G How move ? Total TMU = (1 + 1 + 1 + 10) X0 < 12 I , stage M1 = 130 actuate for 3 5s X10. Total t me = 4 68 sec. none 10 Returns ? NO Ap D! Bo G! M. X!o lo Do get move or actuate return * Tool use + for use w th had tools had as tools , , or bra n as tools Maual Crane & for use w th manual crones i i i i i  Work Sampl!ng · what are the methods for establ!sh!ng t me standards ? - Est mate - Records > - work Measurement techn!ques what are the work measurement techn ques ? · - T!me study - Standard data -T!me formulas - Predeterm!ned t me sustems "work sampl!ng What s work ? sampl!ng · -I s one way to determ ne t!me stadods for longer cucle tasks or low rep tasks. Jalso used : to determ!ne appropr!ate allowance percentage for + use n t me study - n safety assessment -to assess equ pment ut!l!zat!on What ? the work sompl!ng advantages · are - does not requ!re cont nuous obs -less total analyst t me -one analyst can observe mult ple operators what s the l m tat ons of work ? sompl ng · -results are only as good as collect on methodology - may not be pract!cal !f task s < 15 % of total t me What are the charachter!st!cs of a good work sompl ng studu ? > Suff!c!ent of samples - number -Samples collected dur!ng representat ve per!od -Random sampl!ng Theory · Bas!s s b nom al d!str!but!on > poss!ble events (0 1) - only two , + p(x 0) = = P , P(X = 1) = 1 - p -assume n > 30 +p s proport!on of somple possess!ng a charachter st c of nterest - mea = p -Stand err(p) = (pp/n)" i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i  How samples (observat!ons) needed ? · many are n= f(des!red accuracy , proport on of t me of task element) n z p(1 p) = - = 2p(1 - p) Aa2 (Arp)2 It s score from normal d str. Ant s absolute accuracy Art s relat ve accuracy Conf!dence Interval for · : p cl = p [2 - 42[p(1 -p)/n]" Da ↓ ↓ rel!ab!l!ty stadd est mator coeff c ent · CI puts nterval around est mate , s nce cannot expect p = P In repeated sampl!ng from populat!on 100(1-1) percent of all els w ll cata!nP · , Quest!on - - %90 20 05 = 1 645.. /s 20 25 = 1 96.. %99 20. 005 = 2 576. 22 (p( -p)) n Cux0.6) = = = (Arp)2 > 406 - samples should be collected Quest!on 3 C = p = 21 an [Pl -p!/ f the sample aug = 60 % then you can say w th 90 % conf!dence that , n the long run , de t me 0 4 42 % between " 04 36 adly w th 40 % be!ng the most l!kely est mate, f th!ngs stay the some [oux0.1062. -- 1 645 1. 645[0. 4x0. 6/406] = 36. 0 Fl i i i i i i i i i i i i i i i i i i i i i i i  Quest!on ( = p = 21 - x(p(l - p)/n]" pIDa Aa = IAa = Arp = [1. bur [0. 33 (0. 67)/406]" =1 0 0384. Arp = 11 64 % wh ch does not meet relat ve (% 10). accuracy goal ↳ 1. Quest!on n = 2 -(p(1 p)) = - (1. 96)2(0 25 x0 75).. = 288 12. Aa2 10 0532. > - 289 must be collected Representat!ve Sample ? s the goal of sampl!ng study · what a work elt s to collect data that accurately reflect true cond!t!ons · Cons!der the effects of the follow!ng when des!gn!ng a study : e strat!f!cat!on -Separate dota by Strata for more !nfoldous sh!fts ) ,... -!nfluence ~ do not let obs. !nfluence what you are observ!ng -Per!od!c!ty > - can occur n work - should not occur n sampl!ng i i i i i i  Data Analys!s Use 2x2 table and Ch!-spr d!str!but!on : X =n.. (Inuna-N!znal-0. n.. ) n. nz n 1 n 2... Quest!on 2 X (Innzz-manz!l-0 n ) n..... = 1452/1122 * 640-90 * God-o 5 *52)"=. 5 72. 722 * 730 S * 1240 * N.2 R. IR 2.. 212 · What are the Work Sampl!ng Data Collect!on Methods ? > - Ind!rect D rect v - n person · d!ar!es random rem nders · · v!deo · event counter i i i i i  Use to Establ!sh Labor Stadods total obs of ↑ element NT! n!TR Performace rat!ng factor = > NP total operator t me n study V normal elemental t!me ( Total prod for obs. Fal. to per!od obs. n study OT! = n!T NP ↓ observed elemental t me NT! = OT!R ST! = NT! (1 + Allowance) ↳Stadedelemental t!me Quest!on 107 235 2400 ⑳ toplae OT! = (n!T)/Np ST! = NT! (1 + Allowace = (107x2400 = 0 9629x(1 09) 0 9927.. =. 235x1100 = 1. 0496 NT! = 0 T!R = 97 0 9927. x 0. = 0. 9629 i i i i