8/3/2019 CNC Turning Machine

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 CNC Turning Machines, poetry in motion

Computer Numerical Control for machining also known as CNC is the process of 

automating machine tools that allows for the repeated and precise reproduction of 

components. CNC machines used to cut metal have been divided into three main groupsnamely Vertical Machining Centres (VMC), Horizontal Machining Centres (HMC) andLathes and Turning Centres. The CNC system allows for control of a direction of motion

along an axis that can be linear or rotary. An axis can be visualized as an imaginarystraight line that runs through the centre of an object. The motion for each axis is carried

out by a mechanical device that is powered by a drive motor via a ball screw. When the ball screw rotates the mechanical device moves.

A helically grooved or threaded screw and a nut form the basis of a ball screw assembly.

When the nut and screw rotate, ball bearings move between the grooves in a continuous path with little friction thereby converting rotary motion to linear motion. The drive

motor is also know as a servo motor and has an output shaft that can be positioned by acoded signal. Changes in the coded signal lead to changes in the angular positioning of 

the shaft.

A CNC lathe is a machine tool that makes cylindrical parts and comes in many differentsizes and forms and is called a Turning Centre. These CNC turning machines can

 perform various sophisticated and precise milling and drilling operations. CNCmachining parts manufacturers can offer advice on development and prototypes for high-

tech components taking into account component design and machine tolerances. Thetolerance refers to a deviation in measurement from the preferred dimensions and is

usually very small.

Turning produces cylindrical shapes using a single point tool usually in a stationery position while the workpiece rotates. A workpiece is an object being worked on by a tool

or a machine. Factors affecting the turning process include workpiece shape, type of material and component specifications in addition to costs. Usually two movements are

combined in the turning process namely feeding movement of the tool and the rotation of the workpiece. Specialised turning operations include grooving, threading and boring.

Although the turning process is meant to cut a workpiece to its desirable specificationsthe chips produced in the cutting process are equally important and need to comply with

suitable standards so as not to pose a threat to the process or the operators.

Just as the creativity of the poet produces a poem in the correct structure for it to work  beautifully so the final product after the turning process should result in a component of 

specific size, shape and finish as originally visualized and designed by the engineer.