STOPWATCH TIME STUDY

STOPWATCH TIME STUDY DEFINITION

Stopwatch time study is used to develop a time standard based on observations of one worker taken over number of cycles. That is then applied to work of others of the same organization who perform the same work. Stopwatch Time Study makes direct observations by means of a simple stopwatch measuring, generally, to the precision of 0.01 minute. The observation equipment consists of the stopwatch, the recording board, the observation sheet and a pencil.

1880-Fredrich W. Taylor started using the stop watch for studying work Time Study is Defined as the process of determining the time required by a skilled, well trained operator working at a normal pace doing a specific task. Several types of Stopwatches could be used: 1.Snapback: in one hundredths of a minute 2. Continuous: in one hundredths of a minute 3.Three watches: continuous watches 4. Digital: in one thousands of a minute 5.TMU(time-measured unit): in one hundred thousandths of an hour 6. computer: in one hundred thousandths of a minute

List of Time Study Equipment and FormEquipment and type Stopwatch Fly-back type Non-flyback type Split hand stop watch Time Study Board Remark

Fly-back type with decimal minute type, having smallest graduation equal to 1/100th of minute is the most common one.

Used to hold time study sheet properly. Generally made of plywood or plastic sheet For recording observations on a predesigned printed or zeroxed form.

Time Study Form

Time study procedure: Step 1.Select the job to be study Step 2.Collect the information about the job Step 3.Divide the job into elements Step 4.Do the actual time study Step 5.Extend the time study Step 6.Determine the no. of cycles to be timed. Step 7.Rate, level, and normalize the operators performance Step 8.Apply allowances Step 9.Check for logic Step 10.Publish time standard

Step 1. Select the job to study. Once the reason for studying the job has been determined, the time study technician may have several people doing the same job Those people you dont want to time study are; 1.The fastest person on the job 2. The slowest person on the job 3.Employees with negative attitudes that will affect their performance while being studied. The person to be time studied should have sufficient time on the job to be qualified, well-trained operators.

For this reason Operators name and months on the job have been included in the on the time study form. Once the job have been selected to study, the following information has been determined: Part no. Operation no. Drawing no. Machine name: a generic name like press, welder, lathe, drill, and so on. Machine no. Department

Step 2. Collect the information about the job. The information required is as follows: Operation description Drawing number which lead to a blue print to show items like the ff: a. Part description and material specification b. Tool numbers, and sizes of tools such as fixtures, drill sizes c. Feeds and speeds of equipment The technologist must check the ff: Is quality ok? Has safety been checked? Is the set up properly done?

Step 3: Divide the job into elementsElements are units of work that are indivisible. Time study elements should be as small as possible, but not less than .030 minute. Principles of Elemental Breakdown 1. Its better to have many elements than to few. 2. Elements should be short as possible. 3. Elements that end in sound are easier to time because the eyes can be looking at the watch while ears are anticipating the sound. 4. Constant elements should be segregated from variable elements to show a truer time.

5. Separate the machine-controlled elements from the operator-controlled elements so work pace can be differentiated. 6. Natural breaking points are the best. 7.The element description describes the complete job, and the ending points are clearly marked. 8. Foreign elements should be listed in order of occurrence. Reasons for breaking down a job elements are as follows:1. 2.

It makes the job easier to describe. Different parts of the job have different tempos

3. Breaking down the job into elements allows for moving a part of the job from the operator to operator. 4. Standard data can be more accurate and more universally applied with smaller elements. On the time study form shown in fig.3-7 and 3-8, two columns have been assigned to elements: The element number Element description Foreign elements.

Step 4. Do the actual time studyThis is the essence of stopwatch time study. This is the recording of time for each element. This form can be used either snapback or continuous time study. Continuous time study -the stopwatch remains running through the duration of the study and element ending times are recorded behind the R reading.

Example of Continuous Study1 R Load clamp E R Run machine E R Unload and place aside E .66 1.33 2.01 2.67 3.32 .55 1.23 1.90 2.57 3.23 .16 2 .83 3 1.50 4 2.17 5 2.83

Snapback -allows the technician to read the watch and reset it immediately to the next element. Example of snapback1 R Load clamp E R Run machine E R Unload and put aside E .10 .10 .11 .10 .09 .40 .40 .40 .40 .40 .16 .17 .17 .16 .16 2 3 4 5

5. Extend the time study Subtract the previous reading from each reading. Subtracting the beginning time from the ending time gives elemental time. Total/ cycles: the total refers to the total time of the appropriate cycles timed. Foreign elements are eliminated from further considerations. Cycles are the number of applicable elemental times included in the total time. Average time is the result of dividing total time by the number of cycles

Percent Rating (%R) refers to your opinion of how fast the operator was performing. Normal Time is defined as the amount of time a normal operator working at a comfortable pace would take to produce part. Normal time=Average time x (rating percent/100) Frequency indicates how often the task is performed. Unit Normal time is calculated by multiplying the frequency by the normal time.

Examples in computing unit normal time:

Normal time

Frequency

Unit normal time

1.160 .400 .100 .050

x x x x

1/1,000 1/10 1/2 1/1

= = = =

0.001 minute .040 minute .050 minute .050 minute

Step 6. Determine the number of cycles to be timed. The accuracy of the study depends on the number of cycles timed: The more cycles that are studied, the more accurate is the study. Almost 5 percent w/ a 95 percent confidence level.

Step 7. Rate, level, and normalize the operators performance. Rating, leveling and normalizing all mean the same thing and the term rating is used from this point on. Rating is the process of adjusting the time to taken by an individual operator to what could be the expected from a normal operator. Rating an operator includes four factors: 1. Skill 2. Consistency 3. Working conditions 4. effort

Step 8. Apply Allowances. Allowances are needed to a time study to make the time standard practical. Total normal time + allowances= standard time There are several methods of applying allowances, and there are several types of allowances like: 1.Personal 2.Fatigue 3.delay.

Step 9. Check for logic. Once the time study has been extended, the test for logic should be applied in two ways: 1.The average time should look like the elemental tines if an error in adding was made, a test for logic will prevent mistake. Read stopwatches in two places: .01. From average time on, use three places: .001 Hours per unit are five places: .00001. 2. The second test for logic is the total normal time for one unit during your study you time a specific number of parts in a certain amount of time.

Step 10. Publish the time standard. The three numbers are required to communicate a time standard: 1. Decimal minutes 2. Hours per unit 3. Pieces per hour Hours per unit refers to the standard minutes dividing by 60 minutes per hour. Pieces per hour is equal to 1/ hours per unit.