One of my readers has suggested me to write one
article about basic of grinding. We have discussed in our previous post about
the working principle of milling operation, today we will see the basic of grinding
in this post.
What we will understand at the end of this post? We will
secure following information here
- Understanding the fundamental concept of grinding: Process of grinding
- Abrasives materials
- Advantage of grinding
- Types of grinding
- Application of grinding
Process of grinding
Grinding is the most common type of material cutting
and surface generation process. Mostly grinding process is used to shape and to
provide better finishing parts of metals. Grinding process uses one abrasive
tool to make controlled contact with workpiece surface.
Normally grinding wheel is used as abrasive tool in process of grinding. Grinding wheel will have grains of abrasive materials and these grains of abrasive material will be termed as grit. Size of abrasive materials plays a very important role in grinding process as larger size grains will remove material faster from workpiece surface but will not provide better surface finish, whereas smaller grain size will remove material slowly from workpiece surface but will provide better surface finish.
Normally grinding wheel is used as abrasive tool in process of grinding. Grinding wheel will have grains of abrasive materials and these grains of abrasive material will be termed as grit. Size of abrasive materials plays a very important role in grinding process as larger size grains will remove material faster from workpiece surface but will not provide better surface finish, whereas smaller grain size will remove material slowly from workpiece surface but will provide better surface finish.
Also read
These grains of abrasive material i.e. grits will
have sharp edges or points with enough hardness as compared to workpiece
surface hardness and wear resistance and these grits will act as cutting tool
in process of grinding to remove small-small particles from workpiece surface.
Image courtesy: Google
According to society of manufacturing engineers,
Surface finishing and precision secured by grinding process will be approximate
ten times better as compared to milling or turning process of machining.
Abrasive materials
Let us see the types of abrasive materials used for
making the grinding wheel, which is key component in grinding process.
- Aluminum oxide grinding wheel is commonly used in making the grinding wheel and will be best suited for grinding the ferrous metals having high tensile strength e.g. hard steel, wrought iron etc.
- Silicon carbide grinding wheel is used to grind the softer, low tensile strength, high density and non-ferrous materials such as brass, aluminum and softer bronze.
- Cubic boron nitride (CBN) grinding wheel is used to grind hard ferrous material, CBN grinding wheel is used approximate 5% of grinding operation.
- Diamond grinding wheel is also used rarely and best suited for hard non metal and non ferrous materials.
Performance of grinding wheel will be dependent on
grain size, pore structure and bond type. Service life of grinding wheel will
also depend on the application of coolant. Application of coolant in grinding
process will reduce the power requirement of grinding machine as well as will
provide the better quality of grinding also.
Normally it is considered that material removal rate
in grinding process is lower while better surface finish and precision will be
secured in grinding process, but these days with advancement in technology for
development in grinding wheel and grinding machine, we are introduced with
abrasive machining where better precision and surface finish with high material
removal rate could be secured during grinding process of unhardened surface of
workpiece.
Factor affecting the quality of workpiece surfaces prepared by grinding process
Let us see following points where we will come to
know about the various factors that influence the workpiece surfaces prepared by
process of grinding.
- Type of grinding wheel: Grinding wheel with smaller grain size will provide the better surface finish, while material removal rate will be low.
- Feed rate: Slower feed rate will provide the precise surface finishing
- Material of workpiece: Material with much hardness will yield the precise surface finishing
- Grinding wheel condition: Damaged grinding wheel will never provide the quality surface finishing.
- Quality of lubricant: Quality coolant in grinding process will reduce the power requirement of grinding machine as well as will provide the better quality of grinding also.
We will continue to our next post where we will see
the various types of grinding process, advantage of grinding process and
finally we will see the application of grinding process.
Do you have suggestions? Please write in comment box
to improve this post.
No comments:
Post a Comment