Time value for an operation defined through PMTS system will be called as SMV.
PMTS (Pre Determined Motion Time System) is a system having pre assigned time values for all the basic motions. So in PMTS only elements are required to be identified in order to get time for an operation.
They include motions such as Put, Grasp, Move, and Release.
Most pre-determined motion time systems use time measurement units (TMU) instead of seconds for measuring time. One TMU is defined to be 0.00001 hours, or 0.036 seconds. These smaller units allow for more accurate calculations without the use of decimals. 1 hr = 100,000 TMU
Calculation of Standard Allowed Minutes (SAM):
Time Value taken from a Trained Operator to perform a defined task having a defined method under standard working conditions is called SAM.
SAM contains time value assigned for a particular operation which defines the Time frame for the work/Operation should be completed
Manufacturing standard data needs to be Accurate & Set to standard conditions.
SAM = Basic Time + Allowance%
Basic Time = Cycle Time x Ratting%
Find Basic Time:
Selected Operation is broken further in to identifiable smaller components (Elements).
All elements are analyzed for their contribution in completing the operation.
All elements which are must to complete the operations are analyzed for their time content.
By summing up the time value for all these necessary elements, we get basic time for operation.
The concept of Rating (known in the US as ‘grading’) is fundamental in time study.
Rating is the process used by the industrial engineer to compare the actual performance of the operator with his/her mental concept of normal performance/standard operator. It is the numerical value used to denote the rate of working.
In order to rate there must be a defined level of performance to compare with, an average level. Standard Operator is fully trained and motivated to perform a defined task (having a defined method) and is, by definition average in terms of his or her work-pace.
Ratting% = (Standard Operator Performance/ Normal Operator Performance) x 100
0 = No activity
1 to 50 = very slow, clumsy operator appears to be half asleep, fumbling movement, weak & no interest in job.
50 to 75 = trying to get output but for their handling problem, less attentiveness they cannot make the quality & output.
76 to 100 = Very faster than other operators. They are working with their 100% concentration & make garments with satisfactory quality & quantity level.