IE Work Design: Productivity and Safety Dr. Andris Freivalds Class #14
IE Maynard Operation Sequence Technique (MOST, pp ) Developed by Zandin in 1967 At SAAB-Scania in Sweden Published in 1980 through H.B. Maynard Basically simplified MTM (same TMU) Faster than MTM-1 and MTM-2 Has many diverse tool applications Has computer program!!
IE MOST – Comparison with MTM FactorMTM-1MTM-2MOST Time to analyze250x100x10x Speed wrt MTM Speed wrt MTM Min. cycle time for 5% accuracy (min)
IE Versions of MOST Maxi MOST –For rare operations (<150/week) –For long cycles (minutes to hours) –Very quick, but less accurate Basic MOST –Between 150 and 1,500 operations/week –Typical cycle times: 0.5 – 3 minutes Mini MOST –More than 1,500 operations/week –Cycle times < 0.5 min –Most detailed and time consuming
IE Basics of Basic MOST - 1 Only three activity sequences: 1)General Move Movement of object freely through space ½ of all work sequences 2)Controlled Move Movement of object attached to another or in contact with a surface ⅓ of all work sequences 3)Tool/Equipment Use 1/6 of all work sequences
IE General Move - Basics Has 4 subactivities: 1)A = Action distance (horizontal) 2)B = Body motion (vertical) 3)G = Gain control (i.e. GET cases A, B, C) 4)P = Placement (i.e. PUT cases A, B, C) Grouped into 3 phases: 1)Get – reach and gain control of object 2)Put – move object to new location 3)Return – distance walked back to workstation, not for hands
IE General Move – Typical Steps 1)Reach some distance with hands for object, perhaps with body motion or steps 2)Gain manual control of object 3)Move object some distance, perhaps with body motion or steps 4)Place the object at specified location 5)Return to workplace (if needed)
IE General Move GetPutReturn A B GA B PA A = Action distance B = Body motion G = Gain control P = Placement Obtain Index Values based on characteristics Sum Index Values, multiply by 10 → TMUs
IE MOST - General Move
IE Ex #1 - General Move GetPutReturn A 6 B 6 G 1 A 1 B 0 P 3 A0A0 A 6 = Walk 3 steps to object B 6 = Bend and arise G 1 = Gain control of light object A 1 = Move object a distance within reach B 0 = No body motion P 3 = Place and adjust object A 0 = No return Walk 3 steps to pick up a bolt from the floor, arise, place bolt in a bolt hole. ∑IV = = 17 17x10 = 170 TMUs
IE General Move - Parameter Indexing Action Distance (A) A 0 ≤ 2 in A 1 within reach A steps A steps A steps A steps Extended values
IE General Move - Parameter Indexing Body Motion (B) B 0 no body motion B 3 sit/stand no adj. B 3 bend/arise – 50% B 6 bend and arise B 10 sit/stand with adj. B 16 variety –Bend and sit –Stand and bend –Climb on or off
IE General Move - Parameter Indexing Body Motion (B) con’t B 16 passing through door (steps before and after are included in value) A 16 B 16 G 1 A 1 B 6 P 1 A 0 = 410 TMU
IE General Move - Parameter Indexing Gain Control (G) G 0 no gain control, hold G 1 light object (simo) G 3 variety –Light objects (non simo) –Heavy or bulky –Blind or obstructed –Disengage (force) –Interlocked –Collect several
IE General Move - Parameter Indexing Placement (P) P 0 no placement, toss P 1 lay aside, loose fit P 3 loose fit blind –Place with adjustment –Double placement –Place with light pressure P 6 heavy pressure –With care or precision –Blind or obstructed –Intermediate moves
IE General Move - Parameter Indexing Return – last A for time for operator to walk back to normal workstation Return – not meant for returning hands Placement with insertion – two lines Repeat cycles - handful of washers on 6 bolts A 1 B 0 G 3 (A 1 B 0 P 1 )A 0 (6) [(1+3) + 6(1+1) + 0] x 10 = 160 TMU
IE Controlled Move – Typical Steps 1)Reach some distance with hands for object, perhaps with body motion or steps 2)Gain manual control of object 3)Move object over a controlled path, perhaps with body motion or steps 4)Allow time for control (a process) to occur 5)Align object at end of process time 6)Return to workplace (if needed)
IE Controlled Move - Basics Has 3 new subactivities: 1)M = Move controlled (path is controlled) 2)X = Process Time (controlled by mechanical devices, not manual actions) 3)I = Alignment (conclusion of process to achieve alignment of objects) Grouped into 3 phases: 1)Get and 3) Return as before 2)Move over controlled path or actuate device
IE Controlled Move GetMove/ActuateReturn A B GM X IA A = Action distance B = Body motion G = Gain control M = Move controlled X = Process Time I = Alignment
IE MOST - Controlled Move
IE Ex #2 - Controlled Move GetMove/ActuateReturn A 1 B 0 G 1 M 1 X 10 I 0 A0A0 A 1 = Reach to lever (within reach) B 0 = No body motion G 1 = Gain control of lever M 1 = Move lever (< 12 in.) to engage X 10 = Process time of ~3.5 sec I 0 = No alignment A 0 = No return Engage a feed lever on a milling machine. ∑IV = = 13, 13x10 = 130 TMUs
IE Controlled Move - Parameter Indexing Move Controlled (M) M 1 one stage ≤ 12 in –or press button/switch/knob M 3 one stage > 12 in –or push/pull with resistance –or seat/unseat –or high control –two stages ≤ 12 in M 6 two stages > 12 in –or with 1-2 steps M stages –or 3-4 steps M steps Extended values Note: Applies to feet also, Ex. Push pedal > 12 in → M 3