GRINDING AND GRINDING WHEEL

  • GRINDING - 
  • 1- Grinding is a finishing operation. 
  • 2- It is accuracy by removing the excess material.
  • 3- Grinding is done on a grinding machine.
  • 4- Which makes use of a grinding wheel rotating at a high speed to cut the material.
  • SPECIFICATION OF GRINDING WHEELS -
  • A grinding wheel is specified by the standard wheel markings like diameter of the wheel, bore diameter of the wheel, thickness of the wheel type (Shape) of the wheel.
  • Example (Marking system)51 - A 46 H8V
  • 51- manufacture symbol for abrasive
  • A - Type of abrasive grant size.
  • 46 - Grain size
  • H - Grade
  • 8 - Structure manufacture own mark(optional)
  • V - Type of bond.
  • GRINDING WHEEL -  
  • 1- It is composed of abrasive particles.
  • 2- A wheel and bonding material known as Binder.
  • 3- There are two types of abrasive. NATURAL ABRASIVE AND                                                    ARTIFICIAL ABRASIVE.
  • NATURAL ABRASIVE-  Its contain Emery, Sandstone,Corundum and Quartz.
  • ARTIFICIAL ABRASIVE- It is two types Aluminium Oxide and Silicon Carbide.
  • GRAIN SIZE -  Coarse, Medium, Fine, Very fine.
  • BOND-  
  • 1- Abrasive grains are held together in a grinding wheel by a bonding material.
  • 2- The bonding material does not cut during grinding operation. 
  • 3- Its main function is to hold the grains together with varying degrees of strength.
  • 4- Standard grinding wheel bonds are vitrified Bond, resinoid Bond, silicate Bond,            shellac Bond, rubber Bond .
  • GRADE - 
  • 1- It is a measured of the holding power or degree of strength.
  • 2- This depend upon the bonding material.
  • 3- the amount of bond determines the wheel hardness or softness.
  • 4- It is three types Soft, Medium, Hard.
  • WHAT IS LOADING -  
  • When while working some particles of metal fastened in to the wheel then wheel stop cutting with the result chattering marks appeared on the job.Is know as loading.
  • WHAT IS GLAZING - 
  • A glazed wheel occurs when the abrasive grains are dull. The cutting                  surface of the wheel appears shiny.

Comments

  1. UnknownJuly 21, 2021 at 7:39 AM

    Sir type of grinding operation ନାହିଁ tk ଦିଅନ୍ତୁ

    ReplyDelete

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