AVIC-Flight Launches "Visual Remote Diagnosis" Service: Quickly Resolve Thread Repair Challenges with Images/Videos

Problem

 Possible Causes

Solutions

Difficulty inserting insert

Threaded hole not tapped properly

Check if the hole dimensions meet standards

Damage to external threads of insert

Replace with a new insert; avoid forced installation

Insert falls out after installation

Hole too large or worn

Use a larger insert

Improper tool usage

nsure the tool is fully inserted to the bottom of the insert

Tool jams during installation

 Tool and insert size mismatch

Verify tool model (e.g., M4 tool cannot be used for M5 insert)

Debris in threads

Clean threads and apply lubricant

Problem

Possible Causes

Solutions

 Bolt cannot screw into insert

Deformed internal threads

 1. Check internal threads with a thread gauge

Incorrect bolt size

2. Confirm bolt and insert have matching pitch (e.g., M6-1.0 vs. M6-0.75) |

 Insert rotates with bolt

Insufficient grip of external threads

1. Switch to self-tapping inserts (e.g., Type S)

Soft base material

2. Apply thread locker (e.g., Loctite 243) for aluminum parts

 Over-tightening

 Insert breaks

1. Follow standard torque (e.g., ≤10Nm for M6 stainless steel bolts)

Material fatigue

2. Upgrade to higher-strength inserts (e.g., Inconel)

Problem

Possible Causes

Solutions

 Insert rust/corrosion

Carbon steel used in humid environments

1. Replace with 304/316 /303 stainless steel inserts

2. Apply zinc or Dacromet coating

Insert loosens under high heat

Thermal expansion mismatch

1. Use high-temperature inserts (e.g., GH2132 alloy, resistant to 800°C)

Weak thread repair in aerospace aluminum

2. Apply high-temperature thread locker

Hydrogen embrittlement

 Hydrogen infiltration during plating

1. Avoid cadmium plating (use hydrogen-free coatings)

2. Bake at 200°C for 4+ hours to remove hydrogen

Problem

Possible Causes

Solutions

The strength of the aviation aluminum parts is insufficient after the thread repair

 Soft aluminum

Poor insert-base bonding

1. Use key-locking inserts

2. Increase contact area (e.g., longer inserts)

 Insert strips in plastic parts

Plastic cold flow deformation

 1. Switch to self-tapping inserts (cuts new threads)

2. Pre-embed metal sleeves

Vibration causes insert loosening

No anti-loosening design

1. Use inserts with nylon locking rings

2. Pair with anti-loosening washers |

 Case  

Traditional Time

Flight Diagnosis Time

 Cost Savings

Stripped threads in battery case

2 hours

8 minutes

¥1,200/instance

Misaligned insert in aerospace aluminum

 3 reworks

1 successful attempt

60% less scrap