Muhammad Junaid

12-mt-29


bsc. mechanical engineering
&
technology

MILLING MACHINE

ITS Operations
&
its parts

milling machine

What is Milling Machine:

        
          Milling Is The Machining Process Of Using Rotary Cutters To Remove Materials From a Work Piece Advancing in a direction at an angle with the axis of the tool.
 

 It covers a wide variety of different operations and machines, on scales from small individual parts to large, heavy-duty gang milling operations. It is one of the most commonly used processes in industry and machine shops today for machining parts to precise sizes and shapes.

types of milling machine

1:Horizontal Milling machine
2:Vertical milling machine

horzontal Milling machine


Vertical milling machine


M

Milling processes

1:Up Milling
2:Down Milling

Up Milling

In Up-milling process (also known as Conventional Milling) the direction of rotation of milling cutter and the direction of work piece feed are opposite to each other. As a result, the thickness of chip at the start is nil and is maximum when the cutting teeth leave the surface of the work piece. During this process the cutting teeth tend to uproot and lift up the work piece from the machine table.

Down Milling

In Down-Milling process (also known as Climb Milling) the direction of rotation of milling cutter and the direction of work piece feed are same. As a result, the thickness of the chip at the start is the maximum and gradually becomes nil when the cutting teeth leave the surface of the work piece. During the process, the cutting teeth tend to push the work-piece into the table.

milling cutters

Milling cutters can be classified mainly on the following bases:

According to direction of rotation of the cutter:

a)      Right hand rotational cutter

b)      Left hand rotational cutter

According to the helix of cutter teeth:

a)      Parallel or Straight teeth cutter

b)      Right hand Helical Cutter

c)      Left hand Helical Cutter

d)     Alternate Helical teeth Cutter

standard milling
cutters

1)      Plain Milling Cutter

a)      Light duty plain milling cutter

b)      Heavy duty plain milling cutter

c)      Helical plain milling cutter

2)      Side milling cutter

a)      Plain side milling cutter

b)      Staggered teeth side milling cutter

c)      Half side milling cutter

3)      Metal slitting saw

a)      Plain metal slitting saw

b)      Staggered teeth metal slitting saw

4)      Angle milling cutter

a)      Single angle milling cutter

b)      Double angle milling cutter

5)      End mill cutter

a)      Taper shank end mill

b)      Straight shank end mill

c)      Shell end mill

cutters

Milling operations

Profile Milling

Pocket Milling

Slot Milling


Profile Milling:

Profile milling is the process of transferring a specific profile onto the work-piece. The formed cutters are used for this process. The cutter of required profile cuts out material from the work piece, transferring the profile onto it in multiple steps.

Steps to perform Profile Milling

1.      Install the Cutter on the arbor of horizontal milling  machine

2.      Fix the work-piece on the vice mounted on the work table

3.      Align the work-piece with the cutter

4.      Start the machine at low RPM

5.      Give a small depth of cut along the z-axis, and feed rate along x-axis and perform one run of cutting

6.      Return to the  initial position by giving feed in the negative x-direction and repeat the process by incrementing  the table position along the  z-axis

Pocket Milling:

Pocket milling is the process of removing material inside some arbitrary closed boundary on a flat surface of work-piece up to a certain fixed depth. The end mill cutters are used for this process.

Steps to perform pocket milling:

1.      Install end mill cutter on the Vertical Milling Machine

2.      Fix the work-piece on the vice mounted on the work table

3.      Setup the spindle speed according to the work-piece and tool materials.

4.      Start the machine, with a small depth of cut, perform  facing operation (machine the entire surface by giving feed along the x and y axis alternately)

5.      Give a small depth of cut along the z-axis, and by giving appropriate feed along the x-axis and the y-axis, perform pocket milling operation.

6.      Increment the table position along the z-axis and repeat the process till the desired depth of profile is achieved

Slot Milling:

Slot milling is the process of cutting slots through a work-piece surface. These slots can be plain slots using the end mill cutter, or the T-slots, using the T-slot cutter.

Steps to perform Slot Milling

1.      Install the end mill cutter on the vertical milling machine

2.      Fix the work piece on the vice mounted on the work table

3.      Setup the spindle speed according to the work-piece and tool materials

4.      Start the machine, with a small depth of cut, perform facing operation (machine the entire surface by giving feed along the x and y axis alternately)

5.      Align the center of the cutter with the center line of the desired slot

6.      Give a small depth of cut along the z-axis and by giving appropriate feed along the x-axis perform cutting operation

7.      Increment the table position along the z-axis and repeat the process till the desired depth of slot is achieved

Well This Is what I had In mind Of Milling Machine If You have any Questions in mind you can Ask!


Thanks....


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