Machining Operations and Machine Tools

Posted in Machining Operations, Mechanical by TheMech On May 10, 2014. No comments

Machining Operations

Machining Operations
Word	Meaning	Context	More Information
Boring	Boring is an operation to enlarge and finish holes accurately. This may be done on a lathe or a milling machine.	Boring is a machine operation in which the work is in contact with a single point tool.	A work piece may be held in a 3, 4, or 6 jaw chuck and collets.
Broaching	Broaching is an operation that completes the cutting in one stroke or cut.	Broaching can be done on both internal and external surfaces.	The teeth of a broaching tool are equally spaced so that as the tool advances into the workpiece, each tooth removes a specified amount of metal.
Drilling	Drilling is an economical way of removing large amounts of metal to create semi-precision round hole or cavity.	Drilling allows a person to make holes through boards, metals, and other materials.	Used for last removal of stock on preparation for other operations like boring, reaming, or tapping.
Drill Press	A machine designed to hold drill bits which will produce cylindrical holes.	Used for producing cylindrical holes, as well as reaming, boring, counter-boring, counter-sinking, honing, lapping and tapping.	There are three major types:- Sensitive drill (light drilling) – Upright drill (heavy duty drilling) – Radial arm drill press (large, heavy workpieces)
Facing	Facing is a lathe operation in which the cutting tool removes metal from the end of the workpiece or a shoulder.	Facing is a machine operation where the work is rotated against a single point tool.	A workpiece may be held in a 3, 4, or 6 jaw chuck, collets or a faceplate.
Gang Drilling Machine	Gang drilling machine performs a number of drilling operations in a sequence.	The gang drilling machine is a series of single spindle drill heads mounted on a long table.	Each head is equipped with a different tool to drill the part being machined as it moves from one station to the next.
Grinding	Grinding is an operation in which the cutting is done by the use of abrasive particles.	Grinding processes remove very small chips in very large numbers by cutting the action of many small individual abrasive grains.	The abrasive grains are formed into a grinding wheel.Very smooth surfaces can be accomplished by the use of the proper grinding wheel.
Grinding Machine	Grinding machine machines metal parts with an abrasive wheel which can grind to close tolerances.	Grinding machines can produce parts of the identical size, shape, and finish quality.	Various types of grinding machines:- Plain Surface grinders – Rotary Surface grinders – Tool & Cutter grinders – Universal grinders – Internal grinders
Gun Drilling Machine	Gun drilling machine is a machine used to produce long, deep holes.The operation is called “Gun drilling”.	In some drilling machines, the gun drill is held firm in a machine and the workpiece revolves; in other cases the work is stationary and the tool revolves.	Uses three types of spindles for producing deep holes:- way – quill – fixed-spindle
Honing	Honing is an internal cutting technique that uses abrasives on a rotating tool to produce extremely accurate holes that require a very smooth finish.	Honing operation	Similar to lapping where abrasive sticks are mounted in a rotating tool.Capable of accuracies of less than 1/10,000th of one inch.
Horizontal Milling Machine	A horizontal milling machine uses a rotating tool to produce flat surfaces.Used for heavy stock removal.	The milling machine provides cutting action with a rotating tool.	The spindle is mounted on a horizontal position. Available in different size tables.
Lathe	The lathe is used for producing cylindrical work. The workpiece is rotated while the cutting tool movement is controlled by the machine.	The lathe is primarily used for cylindrical work.	The lathe may be used for:boring, drilling, tapping, turning, facing, threading, polishing, grooving, knurling, trepanning
Non-Precision Grinding	Non-precision grinding is a cutting technique used when the grinding does not need to be accurate.	Non-precision grinding is done when accuracy is not important.	Non-precision grinding is a free-hand operation done on a pedestal or bench grinder.
Precision Grinding	Precision grinding is a cutting technique used when close tolerances and very smooth finishes are required.	Precision grinding as often used as a finish machining process.	Precision grinding allows very small amounts of material to be removed from a workpiece. This is extremely useful in acquiring smooth fnishes.
Reaming	Reaming is a sizing operation that removes a small amount of metal from a hole already drilled.	The reamer is the tool used for this operation.	Machinists may use hand or machine reamers depending on the job they are performing.
Shaper	Shaper is a machine used for the production of flat surfaces in vertical, horizontal, or angular planes.	The shaper cuts by passing a single point tool by the workpiece.	There are three types of shapers:- Horizontal / plain or universal – Vertical (slotter and key seater) – Special
Shaping	Shaping is an operation used to produce flat surfaces.	Shaping	When the cutting tool reciprocates while the work is fed towards the tool removing material on each stroke, it is called shaping.
Single Point Threading	Single point threading is a lathe operation used for creating internal / external precision machined threads with a single point tool.	Single point threading	Uses a special cutting tool that reflects the thread form.There are over 100 thread forms.
Sensitive drill press	Sensitive drill press is a high speed machine that drills very small holes.	The sensitive drill press	– it is used for light duty work- extremely precise quill and spindle – capable of speeds of over 40,000rpm – maximum drill size of 1/32 of an inch
Tapping	Tapping is the process of cutting a thread inside a hole so that a cap screw or bolt can be threaded into the hole. Also, it is used to make threads on nuts.	Tapping is done with a tool called a “Tap”.	Tapping may be done by:- hand – lathe machine – milling machine – tapping machine
Turning	Turning is a lathe operation in which the cutting tool removes metal from the outside diameter of a workpiece.	A single point tool is used for turning.	A workpiece may be held in a 3, 4, or 6 jaw chuck, collets or may also be held between centers.
Vertical Milling Machine	A vertical milling machine uses a rotating tool to produce flat surfaces. A very flexible, light-duty machine.	The milling machine provides cutting action with a rotating tool.	The spindle is mounted on a vertical position. Available in different size tables.