STOPWATCH TIME STUDY! ANALISA DAN PENGUKURAN KERJA. Debrina Puspita Andriani Blog':'

Transkripsi

1 STOPWATCH TIME STUDY! ANALISA DAN PENGUKURAN KERJA 10 Debrina Puspita Andriani Blog':'

2 METODE PENGUKURAN [WAKTU] KERJA PENGUKURAN)[WAKTU]) KERJA) DIRECT' INDIRECT' STOPWATCH' STANDARD' DATA' WORK' SAMPLING' PMTS) Regression' Analysis' 2)

3 DIRECT VS INDIRECT TIME STUDY DIRECT)TIME)STUDY)! Kelebihan':'! PRAKTIS,'karena'hanya' mencatat'waktu'saja'tanpa' menganalisa'gerakan"gerakan' kerja.'! Biaya'lebih'murah'(pada' awalnya).'! Kekurangan):)! Dibutuhkan'waktu' pengamatan'yang'lebih'lama' agar'data'akurat'&'teliti.'! Biaya'lebih'MAHAL'karena' harus'datang'langsung'ke' lokasi'pengamatan'(pada' akhirnya).' 3) INDIRECT)TIME)STUDY)! Kelebihan):)! Waktu'pengamatan'relatif'SINGKAT' karena'cukup'merekam'aktivitas' kerja.'! Biaya'relatif'lebih'MURAH'karena' tidak'perlu'berulang'kali'datang'ke' lokasi'pengamatan.'! Jumlah'pengukuran'tidak'harus' sebanyak'penghukuran'langsung'! Kekurangan):)! Terkadang'tabel'gerakan'kerja'orang' EROPA'tidak'cocok'dengan' INDONESIA.'! Dibutuhkan'KETELITIAN'yang'tinggi' dalam'membreakdown'gerakan" gerakan'kerja.'! Data'waktu'gerakan'kerja'harus' disesuaikan'dengan'jenis' PEKERJAAN.'

4 Element'is'a'component'of'job'or'task'that'are' logical'divisions'with'easily'identifiable'starting' and'end'points,'and'are'repeated'on'a'regular' basis.' Cycle'is'the'completion'of'the'activities' (elements)'required'to'perform'the'job'under' study.'' ' 4)

5 Types)of)elements) A'repetitive'element'' is'an'element'which'occurs'in'every' work'cycle'of'the'job.'' An'occasional'element' does'not'occur'in'each'work'cycle' of'the'job,'but'which'may'occur'at' regular'or'irregular'intervals.'e.g.' machine'setting.' For'a'constant'element' the'basic'time'remains'constant' whenever'it'is'performed.'e.g.' switch'the'machine'on.' A'variable'element'' is'an'element'for'which'the'basic' time'varies'in'relation'to'some' characteristics'of'the'product,' equipment'or'process,'e.g.' dimensions,'weight,'quality'etc.' e.g.'push'trolley'of'parts'to'next' shop.' A)manual)element) is'an'element'performed'by'a' worker.' A)machine)element)' is'automatically'performed'by'a' power"driven'machine'(or' process).' A)governing)element)' occupies'a'longer'time'than'any' of'the'other'elements'which'are' being'performed'concurrently.' e.g.'boil'kettle'of'water,'while' setting'out'teapot'and'cups.' A)foreign)element)) is'observed'during'a'study'which,' after'analysis,'is'not'found'to'be' necessary'part'of'the'job.'e.g.' degreasing'a'part'that'has'still'to' be'machined'further.' 5

6 6)

7 Stopwatch T-me Study :! Elemen&kerja&berlangsung&dalam&waktu&SINGKAT&! Waktu&siklus&kerja&PENDEK&! Siklus&kerja&terjadi&BERULANGAULANG&! Waktu&elemen&kerja&diukur&dengan&STOPWATCH) Wor. Sampl-ng :! Elemen&kerja&berlangsung&dalam&waktu&LAMA&! Waktu&siklus&kerja&PANJANG&! Siklus&kerja&TIDAK&BERULANG&! Mencari&%&kerja&dan&%&delay&(PROBABILITAS)& Direct Time Study 7)

8 LANGKAH LANGKAH! PENGUKURAN [WAKTU] KERJA 8)

9 1. Mengumpulkan informasi dan peralatan! Tentukan&TUJUAN&dari&pengukuran&kerja!&! Melakukan&pengamatan&pendahuluan& &(layout,&lingkungan&kerja,&mesin&yang&& &digunakan,&dll).&! Menyiapkan&peralatan&:&! stopwatch,&papan,&kalkulator,&form&pengukuran&kerja&! Memilih&operator&yang&akan&diamaR&dan& mengkomunikasikan&dengan&supervisor&(operator&harus& memiliki&kemampuan&normal,&bisa&bekerja&sama,&dan& WAJAR).) 9)

10 Stopwatch) Electronic)Stopwatch) Mechanical)Stopwatch) LED read-out 10) Calibrated in decimal minutes

11 Learning Curve 11)

12 2. Membagi operasi dalam elemen-elemen! Purpose&:&easy&to&measure&&&line&balancing&! Separate&handling&Rme&(nonAproducRve&Rme)&with&& operaron&rme&(producrve&rme)&! Separate&constant&element&with&variable&element.&! Every&element&must&have&an&easily&idenRfiable& starrng&and&ending&point&(breakpoints)&! ConRnuiRes&between&elements&! Elements&Rmes:&0.04min&(short),&0.25min& (reasonable)&! RelaRve&frequency&must&be&included&& 12)

13 3. Metode Stopwatch Time Study! CONTINUOUS)TIMING))! Tombol'stopwatch'ditekan'pada'saat'awal'elemen'kerja'dan'terus'dibiarkan'berjalan' selama'periode'studi.'' Pengamat'terus'melihat'jalannya'jarum'stopwatch'dan'setiap'awal/akhir'dari'sebuah' elemen'kerja'yang'ada'mencatat'dan'menuliskannya'di'lembar'pengamatan.'' Waktu' setiap' elemen' kerja' akan' diperoleh' dengan' cara' pengurangan ' dan' dilakukan' setelah' studi' pengukuran' kerja' selesai' dilaksanakan.' APA) KEKURANGANNYA?)! REPETITIVE)(SNAP[BACK)METHOD))) 'Jarum'penunjuk'stopwatch'selalu'dikembalikan'ke'posisi'nol'setiap'kali'satu'elemen' kegiatan'selesai'dilaksanakan.'' Waktu'yang'diamati'dan'dicatat'akan'merupakan'waktu'yang'sebenarnya.'' Time2 study2 analyst2 akan' bisa' mendeteksi' dengan' mudah' adanya' variasi' perbedaan' waktu'dari'setiap'elemen'kegiatan.'apa)kekurangannya?)! ACCUMULATIVE)TIMING)) ' Merupakan' kombinasi' cara' pengukuran' dengan' metoda' continuous2 dan2snap6back2 (pengukuran' dilaksanakan' dengan' menggunakan' dua' atau' lebih' stopwatch' yang' bekerja'secara'bergantian).' 13)

14 Continuous Method Snapback Method 14)

15 " Don t'comment'to'the'worker'during' the'task' " Stand'(don t'sit)'beside'the'worker' " Write'every'event'(even'though'it'may' seems'not'important)' " Have'a'good'position'to'observe' " Stop'the'study'if'the'worker'seems'to' be'under'pressure'and'it'affects'his/her' work' THE RULES! 15)

16 PENGAMATAN

17 Time Study Observation Sheet Identification of operation Sandwich Assembly Date 5/ Grasp and lay out bread slices Spread mayonnaise on both slices Place ham, cheese, and lettuce on bread Place top on sandwich, Slice, and stack t R t R t R t R Operator Approval Observer Smith Jones Russell Cycles Summary Σ t t RF Nt Performing a Time Study 17)

18 4. Tes Kenormalan, Tes Keseragaman,! Tes Kecukupan Data " TES) KENORMALAN) #) data' pengamatan' seharusnya' berjumlah'cukup'besar'(banyak)'dan'berdistribusi'normal.' ' " TES)KESERAGAMAN)#'data'harus'homogen'dan'diperoleh' dari'populasi'yang'sama.' ' " TES) KECUKUPAN) #' data' yang' dikumpulkan' telah' cukup' secara' obyektif,' dengan' konsep' statistik'(derajat' ketelitian' dan'tingkat'keyakinan/kepercayaan'yang'diinginkan).' 18)

19 Determining Number of Cycles Time'measurement' ' Measuring'time'of'each' element' The'number'of' observation'of'each' element'depends'on' the)significance)level) and'required)level)of) accuracy) 19)

20 Number of Cycles (1) To)determine))sample)size:) where' n = zs et 'z'=''number'of'standard'deviations'from'the'mean'in'a'normal' distribution'reflecting'a'level'of'statistical'confidence' 2 s = Σ(x i - x) 2 n - 1 = sample'standard'deviation'from''sample' time'study' 'T'=''average'job'cycle'time'from'the'sample'time'study' 'e'=''degree'of'error'from''true'mean'of''distribution' 20)

21 Number of Cycles (2) Example):) Average'cycle'time'='0.361' Computed'standard'deviation'='0.03' Company'wants'to'be'95%'confident'that'computed' time'is'within'5%'of'true'average'time' 2 zs (1.96)(0.03) n = = = or 11 et (0.05)(0.361) 2 21)

22 Recommended)number) of)cycles/observations' 22)

23 5. Performance Rating & Waktu Normal 1)'Waktu'Pengamatan'(T obs )' 2)'T N '<'T Obs 'untuk'p'<'1'(100%)' 3)'T N '='T Obs' untuk'p'='1'(100%)' 4)'T N '>'T Obs' untuk'p'>'1'(100%)' Normal)time):) )T n )=)T obs' (PR)) 23)

24 WESTINGHOUSE RATING SYSTEM 24)

25 6. Menentukan Allowance Allowance) Constant) Special) Personal) Needs) Fatigue)) Avoidable) Delays) Unavoidable) Delays) More)details)in):)Handbook)of)IE)(Salvendy)):)pp.)1409) 25)

26 7. Waktu Standar dan Output Standar Waktu)Normal)(T N )' Allowance' Waktu)Baku/Standard))(T S )' T S' =)T N' (1)+)A pfd )) O S )=)1)/)T S ) 26)

27 Let s Try!'

28 ! Given:'A'direct'time'study'was'taken'on'a'manual'work' element'using'the)snapback)method.''! The'regular'cycle'consisted'of'three'elements':'a,)b,)and) c.' Element) d) is' an' irregular' element' performed' every' five'cycles.'' ' Work)element) a) b) c) d) ' ' ''! Determine'' Observed'time'(min)' 0.56' 0.25' 0.50' 1.10' Performance'rating' 100%' 80%' 110%' 100%' TUGAS 1 '(a)'normal'time'' '(b)'standard'time'for'the'cycle'using)a pfd' ='0.15 ' 28)

29 (a) Normal time: 'T N 2='0.56(1.00)'+'0.25(0.80)'+'0.50(1.10)'+'1.10(1.0)/5'' ' '='1.53'min' ' Solution (b) Standard time: 'T S '='1.53(1'+'0.15)'='1.76'min' 29)

30 Knowing exactly what you want to do, and then seeing that they do it the best and cheapest way. Freder-c. W. Taylor 30)