Metal Cutting is one of the most used production processes in the industry. The process is very flexible and can be used for production of part with complex geometry and fine tolerances. Despite of the importance of this process it is least examined. Furthermore, processes parameters are still chosen based on empirical knowledge. The experimental tests are costly and less relevant these days. Thus, a better analysis of cutting process is necessary in order to select cutting tools and process parameters
Metal cutting is a process of separating metal by applying force on it to get the desired shape. Each parameter is dependent on another, for e.g increase in the speed of cutting might increase the rate of production. But a Tool can be worn out due to continuous cutting.
There are various cutting parameters to look at while cutting a metal.
- Cutting tool Material :
- Carbon steel were preferred in the early days for wood works and setting up aluminum sheets in router. However its use got limited as it softens at about 180 degree C.
- High Speed Steel (HSS) were then used for the manufacture of complex shape tools like power-saw blades and drill bits
- Cemented Carbides an extremely hard material made from tungsten powder can be used in the form of brazed or clamped tips
- Characteristics of the Tool Material :
- The hardness of the material is determined by testing it with a hard steel ball under fixed pressure and noting its resistance against deformation.
- At the start of a cut the first bite of the tool into the work results in considerable shock loading on the tool. The tool must be strong enough to withstand it.
- The tool rubbing against the workpiece and the chip rubbing on the top face of the tool produce heat which must be kept to minimum.
- Cutting Speed and Feed :
- The optimum cutting speed is defined as the speed at which the point on the surface of the work passes the cutting edge or point.
- The productivity depends on the cutting speed, i.e higher the speed greater is the productivity.
- The feed rate is the distance the tool moves per revolution of the workpiece and depends largely on the surface finish.
- For roughing out a soft material a feed upto 0.25 mm per revolution may be used.
- With tougher materials this should be reduced to a maximum of 0.10 mm/rev.
- Cutting Fluid and Lubricant :
- Heat generated due to friction can readily be reduced by using a lubricant. Thus the use of a lubricant and the cutting fluid will serve to reduce the tool wear, give better surface finish and a tighter dimensional control.
- Cutting fluids like water, soluble oils, mineral oils and even vegetable oils can be used.
- Water can be used as a cooling agent during grinding process.
- Soluble oils are suitable for light cutting operations on general purpose machines where high rates of metal removal are often not of prime importance.
- Depth of cutting :
- The thickness which is removed when the workpiece is machined , is known as the depth of cutting the material.
- It determines how much a tool can dig in , to remove the material.
- Rigidity of Machine :
- The age, usage of machine, design and construction of machine all affects the rigidity of machine.
- They are important to decide the accuracy and speed of production.
Thus , to get a good quality , finished metal- cutting machine , all or some of these parameters play an important role. To optimize the process of cutting, different parameters are kept in mind to achieve a desirable outcome. BIPICO Industries set up in Billimora – Gujarat (India) started its operation more than three decades ago. It is a brand leader in different types of Metal Cutting Tools. BIPICO is famous as an exporter and carries a strong brand image in International Markets.
