Time & motion study

• Time Study• Methods, Steps of time study• Allowances• Motion Study• Procedure of Motion Study• Flow Process Chart• Therbligs• Micro-motion Study

Including….

Time study is a direct and continuous observation of a task, using a timekeeping device (e.g., decimal minute stopwatch, videotape camera etc.) to record the time taken to accomplish a task and it is often used when :1.there are repetitive work cycles of short to long duration2.wide variety of dissimilar work is performed, or 3.process control elements constitute a part of the cycle.

Time study

Techniques of Time Study

Direct Time Study: is a determination of quantum of total time required to perform a unit of work. It helps to compare the alternative methods, and determine the labor and staff required for the operations.

Synthesis Method: Adding a few elemental values over the data already obtained in the form of a catalog reading. This gives allowable time for operation to complete.

Analytical Estimating: is used to determine the time values for jobs having long and repetitive nature or values. Such work can be recorded using the synthetic and standard data available.

PMTS: Also called as predetermined motion time study. Computes the natural or basic time set up against motions at a defined level of performances.

Procedure for Time Study

Secure and record information about the operation and operator being studied. Select operators Divide the operation into elements and record a complete description of the method. (before you start study) Assign particular work to operators Observe operators performing task: record time taken for each element. Rate the operator’s performance. Determine appropriate work standards.

Advantages of Time Study

Generally they are required:A.to plan future production andB.to evaluate performance of workers or of the production system as a whole.

Limitations of Time StudyThe followings are the limitations of time study as a technique of

setting production standards:1)Standards cannot be established by this technique on jobs which are not well defined.2)In situations where it is difficult to define quality precisely standards and production incentives may cause deterioration in quality levels.3)Labour unions may oppose the application of time study where they are strong.4)Only specific type of jobs which have identifiable starting and ending points can be timed accurately.

Allowances Relaxation Allowance

– For fatigue and personal needs Contingency Allowance – For duties of periodic nature Tools and Machinery Allowance – For adjusting

machines, sharpening tools, etc.

Reject Allowance – Time used up in producing items which turn out to be

defective Interference Allowance – Stoppage of 2 or machines Excessive Work Allowance – Due to unforeseen temporary changes

Time Recording Techniques in Time Study

Stop Watch MethodTime Recording MachineMotion Picture Camera

Stop Watch MethodTime study equipment includes the following;a)Time study watch

Plain Decimal-Minute Stopwatch Decimal Hour Stopwatch Split-Hand Stopwatch Wink Stopwatch

b)Time study boardc)Time study observation sheetd)Steel rule

Time Study Board

Electronic Time Study Board3-Watch BoardSimple Time

Study Board

Time Study Sheet

Time Recording Machine

Functions on a paper tape Easy time recording Its use eliminates errors of

stopwatch method

Motion Picture Cameraa) Spring Driven Camera(normal

speed 16eps)b) Electric Motor Driven Camera

i. Slow Speed Camera(operates at 50/100fpm)

ii. Normal Speed Camera(operates at 960fpm)

Motion Studyo It is the science of eliminating wastefulnessresulting from using – unnecessary – ill-directed & – inefficient motion.o The aim of the study is to find and perpetuate

the scheme of least waste methods of labour.Motion studies were conducted by Frank and

Lillian Gilbreth about a century ago in a search for the “one best way.”

Procedure of Method StudyJob to be studiedCollection and recording of necessary

informationCritical examination of existing methodDevelop the new improved methodInstall the improved methodMaintain the improved method

Flow Process Chart The flow process chart in industrial

engineering is a graphical and symbolic representation of the processing activities performed on the work piece.

Flow process chart are of three types;

Man Machine & Material

TherbligTherbligs are 18 kinds of elemental motions used in the study of motion economy in the workplace. A workplace task is analyzed by recording each of the therblig units for a process, with the results used for optimization of manual labor by eliminating unneeded movements.

The word therblig was the creation of Frank Bunker Gilbreth and Lillian Moller Gilbreth, American industrial psychologists who invented the field of time and motion study. It is a reversal of the name Gilbreth, with 'th' transposed.

Micro-motion & Macro-motion Study

Studies of overall factory flow or process, called macromotion studies, and then additional studies of detail or operations, called micromotion studies, should be completed for a project.

Importance of T&M Study T&M Studies can be effective for

performance evaluations T&M Studies can be used for planning

purposes in order to predict the level of output that may be achieved

T&M Studies can be used to uncover problems and create solutions

T&M Studies can be used for time cost analysis