Common Fastener Failures and How to Prevent Them | SC Fastening Systems





Common Fastener Failures and How to Prevent Them | SC Fastening Systems



Common Fastener Failures and How to Prevent Them

Fasteners are the backbone of manufacturing, construction, and countless other industries. But when a fastener fails, it can lead to costly downtime, equipment damage, and even safety hazards. Understanding the most common reasons fasteners fail—and how to prevent them—can save you time, money, and frustration.

At SC Fastening Systems, we’ve spent decades helping businesses choose and maintain the right fasteners for their applications. Here’s a breakdown of the most frequent failure types and the steps you can take to avoid them.

Fastener Failure Statistics

75%

Of fastener failures are preventable with proper selection

$50K+

Average cost of unplanned equipment downtime per hour

5 Types

Most common fastener failure modes

1

Corrosion Failure

Why It Happens: Corrosion occurs when environmental factors—such as moisture, chemicals, or salt—react with the fastener material, weakening its structure over time.

️ Prevention Tips:

Material Selection: Choose corrosion-resistant materials like stainless steel or brass
Protective Coatings: Apply zinc plating, hot-dip galvanizing, or specialty finishes
Environmental Protection: Use proper sealing washers or gaskets in moisture-prone environments

Common Environments:

• Chemical processing
• Outdoor structures
• Food processing

2

Fatigue Failure

Why It Happens: Fatigue failure occurs when a fastener is exposed to repeated cyclic loads, causing small cracks that grow over time until the fastener breaks.

Prevention Tips:

Proper Strength: Select fasteners with the correct tensile strength for your application
Avoid Over-Tightening: Prevent unnecessary stress points that can initiate crack formation
Maintain Tension: Use lock washers or thread-locking compounds

High-Risk Applications:

• Bridge connections
• Aircraft components
• Rotating equipment

3

Over-Torque and Stripping

Why It Happens: Applying too much torque can strip threads, deform the fastener, or even shear it completely. This is one of the most preventable failure modes.

Prevention Tips:

Calibrated Tools: Use a calibrated torque wrench to apply manufacturer’s recommended torque
Training: Train staff on proper installation techniques
Grade Selection: Choose higher-grade fasteners for high-load applications

Warning Signs:

  • Stripped threads
  • Deformed heads
  • Metal shavings
  • Sudden torque drop
Common Causes:

  • Impact tools misuse
  • Wrong thread pitch
  • Cross-threading
  • Inadequate lubrication

4

Vibration Loosening

Why It Happens: In machinery or vehicles, constant vibration can gradually loosen fasteners, leading to component separation and potential catastrophic failure.

Prevention Tips:

Locking Mechanisms: Use nylon insert locknuts, lock washers, or thread-locking adhesives
Specialized Fasteners: Consider serrated flange bolts to resist loosening
Regular Maintenance: Perform regular checks to re-torque critical fasteners

Critical Applications:

• Industrial machinery
• Power generation
• Transportation equipment

5

Incorrect Material Selection

Why It Happens: Using a fastener made from the wrong material can lead to galvanic corrosion, breakage, or premature wear when materials are incompatible with the environment or application.

Prevention Tips:

Environmental Matching: Match fastener material to conditions (temperature, humidity, chemicals)
Avoid Galvanic Issues: Don’t mix dissimilar metals that could cause galvanic corrosion
Expert Consultation: Consult with a fastener expert before making substitutions

Material Properties to Consider:

  • Corrosion resistance
  • Temperature tolerance
  • Strength requirements
  • Magnetic properties
Common Mismatches:

  • Steel in marine environments
  • Aluminum with steel
  • Wrong grade for load
  • Non-food grade in food processing

Fastener Failure Prevention Checklist


Design Phase

  • Analyze load requirements
  • Consider environmental factors
  • Select appropriate materials
  • Plan for maintenance access


Installation Phase

  • Use calibrated torque tools
  • Follow proper procedures
  • Apply thread lockers if needed
  • Document installation specs


Maintenance Phase

  • Regular visual inspections
  • Periodic torque checks
  • Monitor for corrosion
  • Replace at scheduled intervals

Cost of Fastener Failures

Direct Costs
  • • Replacement parts
  • • Labor costs
  • • Equipment damage
Indirect Costs
  • • Production downtime
  • • Lost productivity
  • • Emergency repairs
Prevention ROI
  • • 10:1 cost savings ratio
  • • Reduced insurance claims
  • • Improved reliability

Final Thoughts

Most fastener failures can be avoided with the right combination of material choice, protective coatings, proper installation, and regular maintenance. By addressing these factors, you’ll not only extend the life of your fasteners but also protect your equipment and bottom line.

Remember: An ounce of prevention is worth a pound of cure—especially when it comes to critical fasteners.