Title: MOST
1MOST
- Maynard Operation Sequence Technique
- Work Measurement System
2Methods - Time Measurement
- H. B. Maynard was one of three persons
instrumental in the creation of MTM.
3Kjell Zandin, while working in the Swedish
Division of H. B. Maynard in the late 1960s,
detected striking similarities in the sequence of
MTM defined motions whenever an object was
handled.
4Under MOST, the primary work units are no longer
basic motions as in MTM, but collections of these
basic motions dealing with moving object.
5MOST makes the assumption that to move an object,
a standard sequence of events occurs.
6Under MOST, objects can be moved in only one of
two ways
- They are picked up and moved freely through space
-- the GENERAL MOVE. - They are moved and maintain contact with another
surface -- the CONTROLLED MOVE.
7The MOST Family
- Basic MOST -- General Operations
- Mini MOST -- Repetitive Operations
- Maxi MOST -- Non-repetitive Operations
- Clerical MOST -- Clerical Operations
8Maxi MOST is used to analyze operations that are
likely to be performed less than 150 times per
week.
9Basic MOST is used for operations that are likely
to be performed more than 150 times but less than
1500 times per week.
10Mini MOST is used to analyze operations likely to
be repeated more than 1500 times per week.
11The Decision Diagram provides a simple procedure
for selecting the most appropriate MOST Work
Measurement System to use.
12The MOST Decision Diagram is based on /- 5
accuracy and a 95 confidence level.
13System Selection Charts may be used in lieu of
the Decision Diagram for choosing the best MOST
Work Measurement System to use.
14The MOST Standard Form provides the analyst with
a simple, consistent format for analyzing work
using the method.
15It should be possible to complete a MOST analysis
by observing two complete cycles of work in slow
motion.
16If the method is well established and the analyst
knows the operation and conditions, the Basic
MOST calculations can be made from the office and
used to predict the times for a new procedure.
17General Rules for Using MOST
- Each sequence model is fixed.
- No letter may be added or omitted for the General
or Controlled Move Sequence. - In general, no letter may be added or omitted for
the Tool Use Sequence, with a few exceptions.
18General Move Sequence
19Four subactivities constitute the General Move
Sequence
- A Action Distance (mainly horizontal)
- B Body Motion (mainly vertical)
- G Gain Control
- P Placement
20Roughly 50 of all manual work occurs as a
General Move.The percentage runs higher for
assembly and material handling and lower for
machine shop operations.
21The General Move follows a fixed sequence of
steps
- Reach, either directly or in conjunction with
body motions or steps. - Gain control of the object.
- Move the object, as in reach.
- Place the object in temporary or final position.
- Return to the workplace.
22The General Move Sequence Model
23Action Distance (A)
- This parameter is used to analyze all spatial
movement or actions of the fingers, hands, and/or
feet.
24A0 lt 2 Inches
- This is any displacement of the fingers, hands,
and/or feet a distance of 2 inches or less.
25A1 Within Reach
- Actions that are confined to an area described by
the arc of the outstretched arm pivoted about the
shoulder.
26A3 One to Two Steps
- The trunk of the body is shifted or displaced by
walking, stepping to the side, or turning the
body around using 1 or 2 steps.
27More Than 2 Steps
- Used with Action Distance data table to cover
longer movements.
28Body Motion (B)
- This parameter is used to analyze either vertical
motions of the body or the actions necessary to
overcome an obstruction or impairment to body
movement.
29B6 -- Bend Arise
- From an erect standing position, the trunk of the
body is lowered by bending from the waist and/or
knees to allow the hands to reach below the knees.
30B3 -- Bend Arise, 50 Occurrence
- Bend Arise is required only 50 of the time
during a repetitive activity.
31B10 -- Sit or Stand
- A series of several hand, foot, and body motions
to move a stool / chair into position followed by
the body sitting or standing.
32B16 -- Stand and Bend
- This is a case where a sitting person must stand
up and walk to a location to gain control of an
object placed below knee level, where a Bend
Arise is required.
33B16 -- Bend Sit
- This applies when gaining control of an object
requires a Bend Arise followed by a Sit prior
to placing the object.
34B16 -- Climb On or Off
- This parameter variant covers climbing on or off
a work platform on any raised surface (3 ft)
using a series of hand and body motions to lift
or lower the body.
35B16 -- Passing Through Door
- Passing through a door consists of reaching for
and turning the handle, opening the door, walking
through the door, and subsequently closing the
door.
36Gain Control (G)
- This parameter is used to analyze all manual
motions employed to obtain complete manual
control of an object(s) and to subsequently
relinquish that control.
37G1 -- Light Object
- Gain control of an object by grasping it as long
as no difficulty is encountered.
38G1 -- Light Objects Simo
- One hand gains control of a light object while
the other hand obtains another light object.
39G3 -- Light Object(s) Non-Simo
- While one hand is grasping an object, the other
hand must wait before it can grasp the other
object.
40G3 -- Heavy or Bulky
- In grasping a heavy or bulky object there is a
delay between when the object is grasped and when
it begins to move due to weight, bulk, etc.
41G3 -- Blind or Obstructed
- Access to the object is restricted because an
obstacle prevents the operator from seeing the
object or creates an obstruction to the
hand/fingers in attempting to gain control.
42G3 -- Disengage
- An application of muscular force to free an
object from its surroundings typified by a need
to overcome resistance followed by sudden
movement and recoil of the object.
43G3 -- Interlocked
- Interlocked means the object is intermingled or
tangled with other objects and must be separated
or worked free before reaching control.
44G3 -- Collect
- Gain control of several objects jumbled together
in a pile or spread out on a surface.
45Placement (P)
- This parameter is used to analyze actions at the
final stage of an objects displacement to align,
orient, and/or engage the object with other
object(s) before control of the object is
relinquished.
46P0 -- Pickup Objects
- This is placement in which no placement occurs.
The object is picked up and held.
47P0 -- Toss Object(s)
- Another placement where placement does not
occur. The object is released during the action
distance (A) parameter without placing motions
or pause to point the object toward the target.
48P1 -- Lay Aside
- The object is placed in an appropriate locations
with no apparent aligning or adjusting motions.
49P1 -- Loose Fit
- The object is placed in a more specific location
than described by the Lay Aside parameter, but
with tolerances so loose that only a modest
amount of control is needed for placement.
50P3 -- Adjustments
- Adjustments are defined as the corrective actions
occurring at the point of placement, and
recognized by obvious efforts, hesitations, or
correcting motions to align, orient, and/or
engage the object.
51P3 -- Light Pressure
- Because of close tolerances or the nature of the
placement, the application of muscular force is
needed to seat the object.
52P3 -- Double
- With double, two distinct phases occur during
the total placing activity.
53P6 -- Care or Precision
- Extreme care is needed to place an object within
a closely defined relationship with another
object, and characterized by the obvious slow
motion of the placement due to the high degree of
concentration required.
54P6 -- Heavy Pressure
- As a result of very tight tolerances, a high
degree of muscular force is needed to engage the
object.
55P6 -- Blind or Obstructed
- Accessibility to the point of placement is
restricted because an obstacle prevents the
operator from seeing the point of placement, or
creates an obstruction to the hand/fingers when
attempting to place the object.
56P6 -- Intermediate Moves
- Several intermediate moves of the object are
required prior to placing.
57General Move Example
- From a stack located 10 feet away, a heavy object
must be picked up and moved 5 feet and placed on
top of a workbench with some adjustments.
58General Move Example
- An assembly worker gets a handful of washers (6)
from a bin located within reach and puts one on
each of six bolts located within reach, which are
four inches apart.
59General Move Example
- A worker gains control of two fittings that are
within reach and located more than two inches
apart, one at a time, and places them on separate
trays that are within reach and located less than
2 inches apart.
60B3 -- Sit or Stand without Moving Chair
- When the body is simply lowered into a chair from
an erect position, without hand/foot motions
required to manipulate the chair.
61P3 -- Loose Fit Blind
- In this case the operator must feel around for
the placement location before a loose placement
can occur.
62Controlled Move Sequence
63Three new subactivities are found in the
Controlled Move Sequence
M Move Controlled X Process
Times I Align
64The Controlled Move Sequence describes the manual
displacement of an object over a controlled
path.
65The Controlled Move follows a fixed sequence of
steps
Reach, either directly or in conjunction with
body motions or steps. Gain control of the
object. Move the object over a controlled
path. Allow time for the process to occur. Align
the object after the move/process. Return to the
workplace.
66A Controlled Move is performed under the
following conditions
- The object or device is restrained by its
attachment to another object - Its controlled during the move by the contact it
makes with the surface of another object. - It must be moved on a controlled path to
accomplish the activity.
67Move Controlled (M)
- This parameter is used to analyze all manually
guided movements or actions of an object over a
controlled path.
68M1 -- One Stage lt 12
- Object displacement is achieved by a movement of
the fingers/hands/feet not exceeding 12 inches.
69M1 -- Button/Switch/Knob
- The device is actuated by a short pressing,
moving, or rotating action of the
fingers/hands/wrist/feet.
70M3 -- One Stage gt 12
- Object displacement is achieved by a movement of
the hands, arms, or feet, plus body motion,
exceeding 12 inches.
71M3 -- Resistance, Seat/Unseat
- Conditions surrounding the object or device
require that resistance be overcome prior to,
during, or after the Controlled Move.
72M3 -- High Control
- This parameter reflects the need to align an
object using a high degree of visual
concentration.
73M3 -- Two Stages lt 12
- An object is displaced in two directions or
increments a distance not exceeding 12 inches per
stage without relinquishing control.
74M6 -- Two Stages gt 12 -- OR-- With One - Two
Steps
- An object is displaced in two directions or
increments a distance exceeding 12 inches per
stage without relinquishing control.
75M10 -- Three to Four Stages --- OR --- 3 -
5 Steps
- An object is displaced three or four directions
or increments without relinquishing control or
pushed/pulled on a conveyor belt.
76M16 -- Move Controlled with 6 - 9 Steps
- Push or pull an object(s) using 6 - 9 steps.
77Cranking action is performed by moving the
fingers, hand, wrist, and/or forearm in a
circular path more than half a revolution. Less
than this is considered a Push/Pull/Pivot.
78Push - Pull Cranking
- If cranking results in a back - and - forth
movement of the elbow instead of pivoting at the
wrist and / or elbow, it is considered push -
pull cranking.
79Pivotal cranking is more efficient than push -
pull cranking, and should be used whenever
possible.
80Process Time
- Process time is that portion of work controlled
by electronic or mechanical devices / machines,
not by manual actions.
81As a rule of thumb, the process time expressed as
an index number should not exceed 20 of the
cycle time.
82Alignment refers to manual actions following the
Move Controlled or at the conclusion of process
time to achieve an alignment or specific
orientation of objects.
83Within the area of normal vision (a 4 diameter
circle), the alignment of an object to two points
can be performed without any additional eye
times.
84I1 -- To One Point
- Following a controlled move, an object is aligned
to one point.
85I3 -- To Two Points lt 4 Apart
- The object is aligned to points not more than 4
inches apart following a Controlled Move.
86I6 -- To Two Points gt 4 Apart
- The object is aligned to points more than 4
inches apart following a Controlled Move.
87I16 -- Precision
- The object is aligned to several points with
extreme care or precision following a Controlled
Move.
88I3 -- To Workpiece
- A Machining Operations parameter where the
machine tool is aligned to the workpiece prior to
making a cut.
89I6 -- To Scale Mark
- Another Machining Operations parameter, the
machine tool is aligned to a scale mark prior to
making a cut.
90I10 -- To Indicator Dial
- The third Machining Operations parameter, the
machine tool is aligned to the correct indicator
dial setting prior to making a cut.
91Alignment of Nontypical Objects
- Nontypical objects are those that are especially
large, flimsy, sharp, or require special handling.
92Alignment of a nontypical object normally takes
place as a series of short correcting motions (lt
2) following the Controlled Move, usually with
the assistance of stops, guides, or marks.
93Controlled Move Example
- From a position in front of a lathe, the operator
takes two steps to the side, turns the handwheel
two rotations, and sets the cutting tool by
aligning the handwheel dial to a scale mark.
94Controlled Move Example
- A milling machine operator walks four steps to
the quick-feeding cross lever and engages the
feed. The machine time following the 4 lever
action is 2.5 seconds.
95Controlled Move Example
- A material handler takes hold of a heavy carton
with both hands and pushes it 18 across conveyor
rollers.
96Controlled Move Example
- Using the foot pedal to activate the machine, a
sewing machine operator makes a stitch requiring
3.5 seconds process time. The operator must
reach the pedal with the foot.
97The Tool Use Sequence is a combination of the
General Move and Controlled Move activities.
98Tools not listed in the tables that are similar
to a tool in the table can use their time values
for analysis.
99Tool Use Phases
- Get Tool (Object)
- Put Tool (Object) in Place
- Use Tool
- Put Tool (Object) Aside
- Return
100The Tool Use Sequence model makes use of the A,
B, G, and P parameters, which are all
familiar to us, plus the new Tool Use parameters.
101The Tool Use Sequence Model
- A B G A B P A B P A
- consists of the tool use parameters F, L, C,
S, M, R, T.
102Tool Use Sequence Parameters
- F -- Fasten
- L -- Loosen
- C -- Cut
- S -- Surface Treat
- M -- Measure
- R -- Record
- T -- Think
103Fasten / Loosen
- Manually or mechanically assembling or
disassembling one object to or from another using
the fingers, a hand, or hand tools.
104Index values for F and L are determined by
the body member performing the action.
105Finger Spins are the movement of the fingers and
thumb to run a threaded fastener down or out, and
include a light application of pressure for
seating / unseating the fastener.
106Wrist Actions
- Wrist Turn
- Wrist Stroke (with reposition)
- Wrist Crank
- Tap
107Wrist Turn
- During a wrist turn, the tool is not removed from
the fastener during use and not repositioned on
the fastener after an action.
108Wrist Stroke (with reposition)
- In this tool use, after each stroke with the tool
and before making each subsequent stroke, the
tool must be removed from the fastener and
repositioned.
109Wrist Crank
- Wrist crank applies to tools that are spun or
rotated around a fastener while remaining affixed
to it.
110Tap
- This parameter covers the use of a hammer (or
similar device) to exert short tapping motions by
pivoting the hand at the wrist.
111Arm Actions
- Arm Turn
- Arm Stroke (with reposition)
- Arm Crank
- Strike
- T-Wrench (two hands)
112Arm Turn(s)
- Arm Turn(s), applying to ratchets, occur when the
tool is held near the end of the handle,
resulting in a pulling action on the tool.
113Arm Stroke (with reposition)
- Following each stroke or pull with the tool, it
must be removed and repositioned again on the
fastener before making a subsequent pull.
114Arm Crank
- The tool is used with a circular movement of the
forearm as it is pivoted at the elbow or the
shoulder to push or crank the tool around the
fastener.
115Strike
- Strike is the use of a hammer with an up - and -
down motion performed with the hand as it is
pivoted from the elbow.
116T-Wrench (two hands)
- A two - handed arm action, including the reach
for each hand to the opposite handle before
making the next turn, and involving a 180 degree
turn of the T-wrench with each action.
117Power Tools
- The use of electric and pneumatic power wrenches
to run a standard threaded fastener down or out a
length 1 1/2 times the bolt diameter.
118The time values generated by the data card for
power tool use must be compared to the times
generated by the tools used in the shop, and
adjusted if necessary.
119Torque Wrenches
- F6 -- Torque wrench handle length to 10.
- F10 -- Handle length from 10 - 15.
- F16 -- Handle length from 15 - 40.
- In all cases, the value is for one arm action and
includes the time either to align the dial or to
await the click.
120Tool Placement
- As a general rule, the P parameter for the
Fasten / Loosen tools will carry the index values
indicated in the Tool Placement table.
121Tool Use Frequencies Example
- An operator picks up a screwdriver within reach
and tightens two screws with six wrist turns each
and then sets aside the screwdriver.
122Multiple Tool Actions Example
- A screw is fastened with a screwdriver. A total
of 18 spins and 4 wrist turns are necessary.
123Multiple Tool Actions Example
- A nut is fastened with a ratchet wrench.
Following 3 wrist cranks, 6 wrist turns are
applied.
124Tool Use Example -- F / L
- Obtain a nut from a parts bin located within
reach, place it on a bolt, and run it down with 7
finger actions.
125Tool Use Example - F / L
- Pick up a small screwdriver that lies within
reach and fasten a screw with 6 finger actions,
and set aside the tool.
126Tool Use Example -- F / L
- Obtain a power wrench that lies within reach, run
down four 3/8 bolts located 6 apart, and set
aside wrench.
127Tool Use Example -- F / L
- From a position in front of an engine lathe,
obtain a large T-wrench located 5 steps away and
loosen one bolt on a chuck on the engine lathe
with both hands using five arm actions. Set
aside the T-wrench from the machine, but within
reach.
128Cut
129Pliers
- C3 -- Soft Using pliers with one hand and
making one cut. - C6 -- Medium Using pliers with one hand and
making two cuts. - C10 -- Hard Using the pliers with two
hands and making two cuts.
130Pliers
- C1 -- Grip Using pliers to hold an item and
subsequently release the pressure on the item. - C6 -- Twist Close pliers jaws on two wires and
use two twisting actions to join the wires
together. - C6 -- Form Loop Close pliers jaws on wire and
using two actions, bend loop in end of wire. - C16 -- Secure Cotter Pin Use pliers to bend both
legs on cotter pin to hold it in position.
131Index values using scissors are selected
according to the number of cuts used.
132Tool Use Example -- Cut
- An operator picks up a knife from a workbench two
steps away, makes one cut across the top of a
cardboard box, and sets aside the knife on the
workbench.
133Tool Use Example -- Cut
- During a sewing operation, a tailor cuts the
thread from the machine before setting aside the
finished garment. The scissors are held in the
palm during the sewing operation.
134Tool Use Example -- Cut
- Following a soldering operation, an electronic
component assembler must cut off the excess small
- gauge wire from a terminal connection. The
pliers are located within reach.
135Tool Use Example -- Cut
- An electrician working on transmission lines
takes a pair of pliers from the tool belt and
cuts off a piece of line. The line is heavy,
such that 2 hands are needed to cut through the
wire.
136Surface Treat
- Surface Treat covers the activities aimed at
cleaning material or particles from or applying a
substance, coating, or finish to the surface of
an object.
137Index values for cleaning tools are based
primarily on the amount of surface area (sq. ft.)
cleaned.
138Tool Use Example Surface Treat
- Before marking off a piece of sheet metal (4 ft
sq) for a cutting operation, the operator takes a
rag from his or her back pocket and wipes an oily
film from the surface.
139Tool Use Example Surface Treat
- Following a sanding operation, an operator
standing at a workbench picks up a brush located
within reach and brushes the dust and chips from
the working are (6 ft sq), and then sets aside
the brush on the workbench.
140Tool Use Example Surface Treat
- Before assembling three components to a casting,
the operator obtains an air hose (within reach)
and blows the small metal filings left from the
previous machining operation out of 3 cavities.
The distance between cavities is gt 2.
141M10 -- Profile Gauge
- Used to compare the profile of an object to that
of the gauge.
142M16 -- Fixed Scale
- Covers the use of a linear (yardstick) or angular
(protractor) measuring device.
143M16 -- Calipers lt 12
- Covers the use of vernier calipers with a
capacity to 12 inches.
144M24 -- Feeler Gauge
- Covers the use of a gauge to measure the gap
between two points.
145M32 -- Steel Tape lt 6 Ft.
- This parameter covers the use of a steel tape to
measure, from a fixed position, between two
points.
146Micrometers lt 4
- M32 -- Depth measurement
- M42 -- Outside diameter measurement
- M54 -- Inside diameter measurement
147Tool Use Example -- Measure
- Before welding two steel plates, a welder obtains
a square and checks the angle between the plates
to see that it is correct. The square (a profile
gauge) is located three steps away on a workbench.
148Tool Use Example -- Measure
- Following a turning operation, a machinist checks
the diameter of a small shaft with a micrometer.
The micrometer is located on and returned to the
workbench 2 steps away.
149Measure Supplemental Values
- M6 -- Snap gauge OD to 2
- M10 -- Snap gauge OD to 4
- M16 -- Plug gauge go/no-go to 1
- M24 -- Thread gauge go/no-go int/ext to 1
- M24 -- Vernier Depth Gauge to 6
- M42 -- Thread gauge go/no-go int/ext 1-2
150Record
- Write covers routine clerical activities.
- Index value based on number of digits or words
- Mark covers marking object
- Each mark is considered a digit
151Tool Use Example -- Record
- After finishing an assigned job, the operator
picks up a clipboard and pencil (simo) from the
workbench, fills out the completion date on the
job card, and signs his name. He then returns
the board and pencil to the workbench.
152Tool Use Example -- Record
- To order a part, a clerk takes a pencil from her
shirt pocket and writes a six-digit part number
on the requisition form on her desk. She then
clips the pencil back in her pocket.
153Tool Use Example -- Record
- Part of a packing operation involves identifying
the components in the carton. This involves
picking up a felt marker (within reach) and
marking a 6-digit number on the container.
154Think
- Most of the time think occurs internal to the
manual work, but there are times it must be
considered as a separate activity.
155Think -- Inspect
- The type of inspection work were looking at here
is that where only simple yes / no decisions
are quickly made on the existence of a particular
defect in a part.
156Inspect -- Read
- The column Digits or Single Words is to be used
for reading technical data (part numbers, codes,
quantities, etc.) - The column Text of Words is used when analyzing
situations in which the operator reads words
arranged into sentences or paragraphs. - Other, specialized, values exist for reading
gauges, scales, date/time, tables.
157Tool Use Example -- Think
- During a testing operation, an electronics
technician picks up a meter lead, places it on a
terminal, and reads voltage off the meter scale.
The lead is then put aside.
158Tool Use Example -- Think
- Prior to starting a turning operation, an
operator picks up a work order set and reads a
paragraph that describes the method to be
followed. It contains an average of 30 words.
The operator then places the set aside on the
workbench.