Precision cnc machining process for shafts, discs, plates exotic parts

Precision CNC Machining Technology For Shafts, Discs, Plates Other Parts

The General Guiding Principle Of Mold Parts Processing Is To Carry Out Adaptive Processing For Different Mold Parts, Different Materials, Different Shapes Different Technical Requirements. There Are Many Options. However, Achieving The Best Processing Effect Economy Through The Control Of The Processing Process Is Our Focus.

According To The Appearance Shape Of Mold Parts, Parts Can Be Mainly Divided Into Three Categories: Shafts, Discs, Plates Molded Special Parts. The Precision CNC Machining Process Of These Three Types Of Parts Is Generally: Rough Machining - Semi-Finishing - (Quenching, Tempering) - Precision Grinding - Electrical Machining - Benchwork Finishing - Assembly Processing.

1. Heat Treatment Of Shafts, Discs, Plates Other Special Parts

In Order To Obtain The Required Heat Treatment Hardness Of Mold Parts, It Is Necessary To Control The Internal Stress Of Parts During Heat Treatment So That The Dimensional Tolerance Shape Position Tolerance Of CNC Parts Can Be Stable During After Processing. There Are Different Heat Treatment Methods For Parts Of Different Materials. The Process Should Consider Economy, Material Hardenability, Hardenability, Overheat Sensitivity Decarburization Sensitivity.

With The Development Of The Mold Industry In Recent Years, Many Types Of Materials Are Used. In Addition To CrWMn, Cr12, 40Cr, GCr15, Cr12MoV, 9Mn2V Hard Alloys, New Materials Such As Powder Alloy Steel Can Be Used For Some Concave Convex Dies With High Working Intensity Harsh Stress, Such As: S2, S3, V10, APS23S1, G2, G3, G4, G8, Etc. Such Materials Have High Thermal Stability Good Organizational State.

After Quenching, Workpieces Generally Retain Internal Stress, Which Can Easily Lead To Subsequent Finishing Cracking During Work. After Quenching, The Parts Should Be Tempered While Hot To Eliminate Quenching Stress. For Workpieces With Complex Shapes Many Internal External Corners, Tempering Is Sometimes Enough To Eliminate Quenching Stress. Stress Relief Annealing Multiple Aging Treatments Are Required Before Finishing To Fully Release Stress. Different Methods Are Adopted According To Different Requirements. Huiwen Zhizao Is A Machining Factory With More Than Ten Years Of CNC Processing Experience . It Has A Full Range Of Equipment, CNC Turning/Milling/Grinding/Drilling/Processing. Partners With Parts Processing Needs Are Welcome To Call Us For Quotes.

Taking Cr12 Parts As An Example, They Are Quenched After Rough Machining. The Cooling Methods During Quenching Are: Air Cooling (Placing The Heated Workpiece In The Air For Cooling. This Method Is Easy To Operate The Workpiece Deformation Is Small, But The Hardness Is Low The Surface Is Easily Oxidized. It Is Suitable For Workpieces With Small Size, High Precision Uneven Thickness), Oil Cooling (Heating The Workpiece Placing It In Oil, Cooling It To 300℃-200℃, Taking It Out Cooling It In The Air. This Method Is Easy To Operate, The Workpiece Hardness Is High, But The Deformation Is Large, The Workpiece Deformation Is Easy To Occur. It Is Suitable For Workpieces With Large Size Simple Shape), Flat Clamping Cooling In The Air (Placing The Heated Workpiece Between Two Iron Plates Copper Plates Pressing Them, Cooling Them In The Air. This Method Is More Complicated To Operate, But The Workpiece Deformation Is Small, It Is Only Suitable For Workpieces Of Certain Special Shapes), Graded Quenching (Heating The Workpiece Placing It In Nitrate With A Temperature Higher Than The Ms Point, Staying For A Certain Period Of Time, After The Internal External Temperatures Of The Workpiece Are Basically The Same, Taking It Out Cooling It In The Air. This Method Can Only Ensure The Hardness Of The Workpiece, But Also Reduce The Deformation Of The Workpiece. It Is Widely Used For Workpieces With Complex Shapes Small Deformation Requirements). For Example, For Powder Alloy Steel Parts Such As V10 APS23, Because They Can Withstand High-Temperature Tempering, A Secondary Hardening Process Can Be Used During Quenching. Quenching At 1040℃-1080℃, Then High-Temperature Tempering At 490℃-520℃ Repeated Multiple Times Can Obtain Higher Impact Toughness Stability, Which Is Very Suitable For Molds With Chipping As The Main Failure Form.

2. Grinding Of Shafts, Discs, Plates Other Special Parts

There Are Three Main Types Of Machine Tools Used For Grinding: Surface Grinders, Internal External Cylindrical Grinders, Tool Profile Grinding Machines.

During Fine Grinding, The Occurrence Of Grinding Deformation Grinding Cracks Must Be Strictly Controlled, Even If They Are Micro Cracks On The Surface Of The Workpiece, Otherwise They Will Gradually Appear In Subsequent Work. Therefore, The Feed Amount During Precision Grinding Should Be Small, The Cooling During Grinding Should Be Sufficient, The Coolant Medium Should Be Selected As Much As Possible. Parts With Machining Allowance Within 0.01mm Should Be Ground At A Constant Temperature As Much As Possible.

When Grinding Workpieces, Be Sure To Choose Grinding Wheels Carefully: PA Chrome Steel GC Green Silicon Carbide Grinding Wheels Can Be Used For High Tungsten, High Vanadium, High Molybdenum, High Alloy Conditions Of Mold Steel High Hardness Of Workpieces; When Processing Cemented Carbide Materials With High Quenching Hardness, Organic Binder Diamond Grinding Wheels Are Preferred. Organic Binder Grinding Wheels Have Good Self-Grinding Properties, The Precision Of The Ground Workpieces Is Above IT5, The Roughness Can Reach Ra0.16μm. Huiwen Zhizao Is A Machining Factory With More Than Ten Years Of CNC Machining Experience, With Complete Equipment, CNC Lathe/Milling/Grinding/Drilling/Machining. Partners With Parts Processing Needs Are Welcome To Call Us For Quotes.

With The Application Of New Materials, The Application Of CBN Cubic Boron Nitride Grinding Wheels In Recent Years Has Shown Good Processing Effects. The Finishing Effects On CNC Profile Grinders, Coordinate Grinders, CNC Internal External Cylindrical Grinders Are Even Better Than Those Of Other Types Of Grinding Wheels.

During The Grinding Process, The Grinding Wheel Should Be Dressed In Time To Keep It Sharp. When The Grinding Wheel Is Passivated, It Will Slide, Scratch, Squeeze On The Surface Of The Workpiece, Causing Burns, Micro Cracks Grooves On The Surface Of The Workpiece, Which Will Significantly Reduce Its Effectiveness In Future Use.

Most Of The Processing Of Disk Plate Parts Is Done By Surface Grinders. There Is A Certain Degree Of Processing Difficulty When Processing Long Thin Plate Parts. Before Processing, Under The Strong Attraction Of The Grinder's Magnetic Table, The Workpiece Originally Has A Certain Bend To Produce A Straight Deformation Is Close To The Surface Of The Worktable. After Grinding, The Workpiece Deforms Recovers Under The Original Stress. When Measuring The Thickness Of The Plate, It Shows Consistency, But Due To The Deformation Recovery, The Flatness Does Meet The Requirements Of The Mold Parts. The Solution Is To Pad The Workpiece With Equal Height Pads Before Grinding, Block The Workpiece With Blocks Around To Prevent It Moving, The Grinding Head Feed Should Be Small During Grinding, The First Reference Plane Should Be Completed By Multiple Passes. After One Side Of The First Reference Plane Is Processed, This Reference Plane Can Be Adsorbed On The Magnetic Table. The Flatness Of Most Workpieces Can Be Improved By The Grinding Method As Described Above. If The Ideal Flatness Effect Cannot Be Achieved Through One Grinding Process, The Above Process Can Be Repeated Again; After Several Such Grindings, The Flatness Can Meet The Requirements; But When There Are Strict Requirements On The Thickness Of The Plate, The Thickness Allowance Must Be Appropriately Added During Material Preparation Based On Comprehensive Factors Such As The Workpiece Material, Shape, Cutting Processing Method, Heat Treatment Method.

The Characteristic Of Shaft Parts Is That They Are Composed Of Multiple Rotating Surfaces. The Ultimate Precision Processing Method Of Modern Enterprises Generally Adopts Internal External Cylindrical Grinding. During The Processing, The Workpiece Is Clamped Positioned Using The Grinder Chuck Tailstock Center, The Workpiece Is Positioned Using The Head Tail Ejectors. At This Time, The Line Connecting The Chuck The Center Of The Ejector Is The Center Line Of The Workpiece After Grinding. If The Center Line Jumps, The Processed Workpiece Will Have Eccentricity Problems. Therefore, Before Processing, The Concentricity Detection Of The Chuck The Center Ejector The Centering Check Of The Head Tail Ejectors Should Be Done. If The Chuck The Center Ejector Are Used To Clamp Position The Stepped Shaft For One-Time Grinding, The Clamping Part Should Be Subjected To External Cylindrical Grinding Before This Grinding. The Clamping Can Be Centered Positioned During One-Time Grinding. Huiwen Zhizao Is A Machining Factory With More Than Ten Years Of CNC Processing Experience. It Has A Full Range Of Equipment, CNC Turning/Milling/Grinding/Drilling/Processing. Partners With Parts Processing Needs Are Welcome To Call Us For Quotes.

When Grinding Thin-Walled Inner Holes, Consider Using A Clamping Process Table, That Is, Intentionally Leaving A Thick Wall Section During Lathe Machining, Then Cutting It Off After The Inner Hole Is Ground. If No Process Table Is Left, The Clamping Force Should Be Too Large, Otherwise, It Is Easy To Produce "Inner Triangle" Deformation On The Circumference Of The Workpiece. Similarly, The Amount Of Feed For Each Grinding Should Be Small, It Takes Multiple Feeds To Grind To Meet The Qualified Requirements. In Addition, During The Grinding Process, The Coolant Should Be Fully Sprayed To The Grinding Position So That The Iron Chips Abrasive Dust Particles Can Be Smoothly Discharged The Grinding Area.