Aerospace parts machining EDM process typical case sharing

Many High-Precision Complex Parts In Aerospace Products Use Traditional Metal Cutting, Which Has Low Efficiency Low Pass Rate, It Is Difficult To Adapt To The Needs Of Aerospace Missions. However, If The Processing Process Is Improved Electromachining Technology Is Used, Many Problems Can Be Solved. Let Huiwen Zhizao Use Several Typical Cases To Explore The Advantages Of Electromachining Technology In Improving Part Precision, Surface Quality Processing Efficiency. Huiwen Zhizao Is A Machining Factory With More Than Ten Years Of CNC Machining Experience . It Has A Full Range Of Equipment, CNC Turning/Milling/Grinding/Drilling/Machining. Partners With Parts Processing Needs Are Welcome To Call Us For Quotes.

1. Case 1: Using Wire Cutting Technology To Solve The Problem Of Processing Slender Holes In Aerospace Parts

　　As Shown In Figure 1, The Material Of The Part Is: 1Cr18Ni9Ti, The Outer Diameter Is 10.5 Mm, The Inner Hole Diameter Is 4 (Tolerance 0～0.12) Mm, The Total Length Is 23.5 Mm. According To The Design Requirements, The Dimensional Tolerance Of The Inner Hole Diameter 4 (Tolerance 0～0.12) Mm Must Meet The Requirements Of The Drawing. Therefore, The Inner Hole Diameter 4 (Tolerance 0～0.12) Mm Becomes The Difficulty Of Processing This Aerospace Part .

　　Difficulty 1: The Material Is Difficult To Process. 1Cr18Ni9Ti Is Austenitic Stainless Steel With High Toughness, High Thermal Strength, Low Thermal Conductivity, Severe Hardening During Processing, Difficulty In Heat Dissipation. These Factors Lead To High Cutting Temperature At The Tool Tip Easy Generation Of Built-Up Edge, Which Only Aggravates Tool Wear, But Also Affects The Surface Roughness Of The Parts.

　　Difficulty 2: Small Hole High Dimensional Accuracy. The Inner Hole Diameter Is 4 Mm (Tolerance 0-0.12) Mm. Direct Drilling Cannot Meet The Dimensional Accuracy Requirements Of The Drawing. Turning Boring Are Used. Since The Depth-To-Diameter Ratio Of The Hole Is Greater Than 5, The Boring Tool Diameter Must Be Less Than 4 Mm. The Strength Is Low The Tool Tip Is Severely Worn. The Dimensional Accuracy Surface Roughness Cannot Be Ensured. The Hole Has Been Processed By Turning. First, A Φ3.8 Mm Drill Is Used To Drill The Hole, Then A Reamer Is Used To Ream The Hole. Before Each Reaming, A New Reamer Needs To Be Used For Trial Reaming, Then The Reamer Is Manually Ground To Explore The Cutting Parameters. Such Processing Efficiency Is Extremely Low. Each Piece Of Processing Takes About 2 Hours, The Inner Hole Processing Is Prone To Taper. The Qualified Rate Is Only About 30%. For A Long Time, The Quantity Can Only Be Guaranteed By Increasing Production.

　　In Order To Ensure That The Processing Of Aerospace Parts Meets The Design Requirements Of The Drawings, After Many Tests, The Parts Are Turned To The Outer Circle Of Φ10.5 Mm The Length Of 23.5 Mm According To The Drawing Requirements, The Dimensional Consistency Is Ensured To Be Within 0.02 Mm. The Inner Hole Is Drilled With A Φ2 Mm Drill As The Wire Threading Hole For Wire Cutting. Then, The Outer Circle Is Clamped With A Fixture For Alignment,  The Inner Hole Is Processed By Slow Wire Cutting.

Case 2: EDM Solves The Burr Problem Of Wiring Grooves In Aerospace Parts

　　As Shown In Figure 2, The Part Is Welded Two Different Materials, With The Two Middle Sections 1.5 Mm × 3 Mm 1.5 Mm × 3.5 Mm Wiring Grooves Φ1.5 Mm Through-Hole Wiring Holes. The Processing Of The Wiring Holes Wiring Grooves Can Only Be Carried Out After The Rough Processing Of The Single-Piece Segments. Since The Burrs Are Turned Into The Wiring Grooves Holes During The Fine Turning Process Of The Parts, The Removal Of The Burrs Of The Wiring Grooves Holes Has Long Been Completed By The Fitter Using Assorted Files For Chamfering. Since The Distance Between The Two Middle Sections Is Only 5 Mm (See Figure 2), The Space For Using The File Is Narrow, Resulting In Scratches On The Parts During The Filing Deburring Process (See Figures 3 4).

　　It Can Be Seen That Manual Filing Of Wire Grooves Holes Has The Following Disadvantages: ① The Surface Quality Of Parts Is Difficult To Control During The Filing Process, Which Can Easily Cause Scratches On The Surface Of Parts. ② The Efficiency Of Manual Filing Deburring Is Low. ③ The Consistency Of Chamfering Of Wire Grooves Cannot Be Guaranteed By Manual Filing. ④ Secondary Burrs Are Easily Caused After Manual Deburring.

It Can Be Seen That Manual Filing Of Wiring Grooves Holes Has The Following Disadvantages: ① The Surface Quality Of Parts Is Difficult To Control During The Filing Process, Which Can Easily Cause Scratches On The Surface Of Parts. ② The Efficiency Of Manual Filing Deburring Is Low. ③ The Consistency Of Chamfering Of Wiring Grooves Cannot Be Guaranteed By Manual Filing. ④ Secondary Burrs Are Easily Caused After Manual Deburring.

　　According To The Structural Characteristics Processing Characteristics Of The Parts, It Is Proposed To Use The Electrospark Forming Method To Remove The Burrs On The Edges Of The 1.5 Mm × 3 Mm 1.5 Mm × 3.5 Mm Wiring Grooves Φ1.5 Mm Wiring Holes. According To Figure 5, The Electrode Shown In Figure 6 Is Designed Processed.

　　The Process Test Shows That The Burrs On The Edges Of The 1.5 Mm × 3 Mm 1.5 Mm × 3.5 Mm Wiring Grooves Φ1.5 Mm Wiring Holes Of The Parts Can Be Removed By Using The EDM Processing Method, Which Has The Following Advantages: ① The Deburring Process Of The Parts Is Controllable Will Cause Scratches On The Surface Of The Parts. ② The Labor Intensity Is Greatly Reduced. ③ The Operation Process Is Controllable, Time-Saving Efficient, The Processing Efficiency Can Be Increased By More Than 50%. ④ The Consistency Of Chamfering Can Be Guaranteed, Which Is Suitable For Mass Production Of Parts. The EDM Processing Has A Good Effect, The Processing Effect Is Shown In Figures 7 8.

The Above Typical Case Analysis Shows That With The Rapid Development Of Electromachining Technology, Many Problems That Are Difficult To Solve By Traditional Metal Cutting Can Be "Easily Solved" By Using Modern Electromachining Technology. Practice Shows That Electromachining Can Only Improve The Processing Qualification Rate Surface Quality Of Parts, But Also Improve Processing Efficiency Reduce Costs. We Have Long Been Committed To The Processing Of High-Precision, High-Difficulty, Easy-To-Deform Metal Plastic Parts , Small Medium-Scale Production Manufacturing Of Lightweight Alloy Composite Materials (Such As Aluminum Alloy, Carbon Fiber, Etc.),  Robot Parts Procurement Customization Services. Therefore, Huiwen Must Continue To Innovate Develop Ideas, Use The Advantages Of Electromachining Technology Combined With Advanced Metal Cutting Technology To Develop Efficient High-Quality Processing Plans, Improve The Processing Accuracy Qualification Rate Of Parts, Ensure The High Reliability Of Aerospace Products.