Friday, July 8, 2011


                    “AIIE” (American Institute of Industrial Engineers) defines Industrial Engineering as  “Concerned with the design, improvement & installation of integrated systems of people,materials,equipment & energy”.

                     Production is any process or procedure developed to transform a set of input elements like men, materials, capital, information and energy into a specified set of output like finished products & services in proper quantity & quality, thus achieving the objectives of an enterprise.

                      Productivity is defined as the ratio between Output & input.
        Output means the amount produced or the number of items produced & inputs are the various resources employed. i.e; land & building, equipments & machinery, materials, labour etc.

               Productivity = Actual Production / Standard Production
                Productivity = Output / Input

Difference between Production & Productivity:
                  Production = 100 Pcs i.e; Quantity produced irrespective of inputs

                  Productivity = 100 Pcs (Output) for 10 Machines (Input)
                                          = 100Pcs / 10 Mc
                                          = 10 Pcs per Machine

ð     Productivity = Rate of Pcs Produced Per Machine (Or any other input factor)

Some Important Formulas :

1. Machine Availability % =
Machine Available time   x 100 %

Total Machine Time


 2. Machine Utilization % =
Actual Running Time  x 100 %       =
No of M/C's Used X Working Hours  X 100 %

Machine Available Time
Total Available Hours X Working Hours


 3. Machine Efficiency % =                  
Standard Running Time  x 100 %     

Actual Running Time

 4.Machine Effective Utilis % =   
Standard Running Time  x 100 %     

Machine Available Time


 Work Measurement may be defined as the application of different techniques to measure & establish the time required to complete a job by a qualified worker at a desired level of performance.
Operation analysis is a detailed study of different operations involved in doing a work.Operation analysis becomes necessary in order to investigate the short comings of the existing method & to develop an improved procedure.

    The purpose of motion analysis is to design an improved method which eliminates unnecessary motion & employs human efforts mor productively.
Steps involved in motion analysis are:
  1. Select the operation to be studied
  2. List & chart various motions performen ny the operator.
  3. Identify the Produtive & Idle motions
  4. Eliminate the unnecessary & non productive motions
  5. Redesign the existing operating procedure by employing minimum number of motions in the most appropriate sequence & in accordance with the principles of motion economy.


       Therbligs was suggested by F.B.Gilberth.Therbligs are used to describe the basic elements of movements or fundamental hand motions of the work cycle.Every therblig is represented by a symbol, a definite colour and with a word or two to record the same .
For example;therblig Grasp has the symbol “U”, Red colour & is denoted by the word “G”

For Example.,
Macroscopic motion
Microscopic Motion(Therbligs)
1.Operation of Picking up a screw driver
1.Reach havd for Screw driver(Transport empty)

2.Grasp the same (Grasp)

3.Take away the Screw driver(Transport Loaded)

(Refer Industrial Engineering & Management by O.P.Khanna,Page no 9.16 for Symbols List)

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