Page 29 - Electrician - TT (Volume 1)
P. 29

ELECTRICIAN - CITS                                                                                                                                                                               ELECTRICIAN - CITS




           Flexible blades: For these types of blades only the teeth are hardened.  Because of their flexibility, these blades
           are useful for cutting along curved lines (Fig 19).
           Saw blades for hacksaws are available with small and large cutting of teeth, depending on the type and size of
           material they are to cut.  The size of the teeth is directly related to their pitch, which is specified by the number of
           teeth per 25mm of the cutting edge.  Hacksaw blades are avaialable in pitches of: (Fig 20)
           •   14 teeth per 25 mm

           •   18 teeth per 25 mm
           •   24 teeth per 25 mm
           •    32 teeth per 25 mm.


              Fig 19                                            Fig 20




























            Standard and standardisation

           Objectives: At the end of this lesson you shall be able to:
           •  state what is meant by standardisation and standard
           •  state the names of various standard organisation
           •  read and interpret the basic concept of electrical code 2011
           •  state the types of injury caused by the improper lifting method
           •  describe the procedure to be followed for moving heavy equipmental.


           Standardisation can be defined as the process of formulating and applying rules for an orderly approach to
           specific activity for the benefit of the user and the manufacturer, and in particular for the promotion of optimum
           overall economy taking due account of functional conditions and safety requirement.
           It is based on the consolidated results of science, technique and experience.  It determines not only the basis for
           the present but also for future development, and to  keep pace with progress.
           The materials/tools/equipment produced in any country should be of certain standard. To meet this requirement,
           the international organisation for standarization(ISO) is started and specifies the units of measurement,  technology
           and symbols, products and processes, safety of persons and goods through a number of booklets coded with ISO
           number.








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                                    CITS : Power - Electrician & Wireman - Lesson 1- 4
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