What are the ways of precision CNC machining holes?

Compared With The Outer Circle Surface Processing, The Conditions For Precision CNC Hole Processing Are Much Worse, Hole Processing Is More Difficult Than Outer Circle Processing. This Is Because:

1) The Size Of The Tool Used For Precision CNC Machining Holes Is Limited By The Size Of The Hole Being Machined, The Rigidity Is Poor, Which Is Prone To Bending, Deformation Vibration;

2) When Machining Holes With Fixed-Size Tools, The Size Of The Precision CNC Machined Holes Often Directly Depends On The Corresponding Size Of The Tool. The Manufacturing Error Wear Of The Tool Will Directly Affect The Machining Accuracy Of The Hole;

3) When CNC Machining Holes, The Cutting Area Is Inside The Workpiece, The Chip Removal Heat Dissipation Conditions Are Poor, The Machining Accuracy Surface Quality Are Difficult To Control.

1. Drilling Reaming

(1) Drilling Is The First Step In CNC Machining Holes On Solid Materials. The Diameter Of The Hole Is Generally Less Than 80 Mm. There Are Two Ways To Drill Holes: One Is To Rotate The Drill Bit; The Other Is To Rotate The Workpiece.

(2) Hole Expansion

Hole Expansion Is The Further Processing Of A Hole That Has Been Drilled, Cast Forged With A Hole Expansion Drill To Enlarge The Hole Diameter Improve The Hole Processing Quality. Hole Expansion Can Be Used As A Pre-Processing Before Finishing The Hole, As The Final Processing Of The Hole With Low Requirements.

2. Reaming

Reaming Is One Of The Finishing Methods For Holes Is Widely Used In Production. For Smaller Holes, Reaming Is A More Economical Practical Precision Machining Method Compared To Internal Grinding Fine Boring.

3. Boring

Boring Is A Precision CNC Machining Method That Uses A Cutting Tool To Enlarge A Prefabricated Hole. Boring Work Can Be Performed On A Boring Machine A Lathe.

4. Honing Holes

Honing Is A Method Of Finishing Holes Using A Honing Head With Grinding Strips (Oilstones). During Honing, The Workpiece Is Fixed The Honing Head Is Driven By The Machine Tool Spindle To Rotate Reciprocate In A Straight Line. During The Honing Process, The Grinding Strip Acts On The Surface Of The Workpiece With A Certain Pressure, Cutting Off A Very Thin Layer Of Material The Surface Of The Workpiece, Its Cutting Trajectory Is A Cross-Net Pattern. In Order To Make The Movement Trajectory Of The Sand Strip Abrasive Grains Non-Repetitive, The Number Of Revolutions Per Minute Of The Honing Head's Rotary Motion The Number Of Reciprocating Strokes Per Minute Of The Honing Head Should Be Prime Numbers To Each Other.

5. Pulling Holes

Hole Boring Is A High-Productivity Finishing Method, Which Is Performed On A Broaching Machine With A Special Broach. There Are Two Types Of Broaching Machines: Horizontal Broaching Machines Vertical Broaching Machines, With Horizontal Broaching Machines Being The Most Common.