Rivet Parameter Encyclopedia: Comprehensive Guide for Industrial B2B Selection, Standards & Maintenance

Rivet Overview: Definition and Basic Principle

A rivet is a permanent mechanical fastener consisting of a cylindrical shaft with a head on one end. It is used to join two or more materials (typically metals, plastics, or composites) by deforming the tail end to form a second head, creating a tight clamping force. The riveting process involves inserting the rivet into pre-drilled holes and then upsetting the tail using a rivet gun, hammer, or specialized tool, expanding the tail to secure the joint. Rivets are widely used in industries where welding or screws are impractical, such as aerospace, automotive, construction, and shipbuilding.

Rivet Working Principle

The working principle of a rivet relies on plastic deformation. When the tail is compressed, it expands radially to fill the hole and forms a second head (called a shop head or buck-tail) on the blind side. This creates a permanent, high-strength joint that resists shear and tensile forces. The clamping force is generated by the elastic recovery of the materials and the residual stress in the rivet. Unlike threaded fasteners, rivets do not loosen under vibration, making them ideal for dynamic loads.

Rivet Classification and Types

Rivets are classified by head shape, material, driving method, and application. Common types include:

Rivet Performance Indicators and Key Parameters

Critical parameters for rivet selection include material, diameter, grip range, shear strength, tensile strength, head size, and coating. The following table shows typical values for common industrial rivets (based on ISO and ASTM standards):

Rivet Industry Standards

Rivets must comply with international standards to ensure interchangeability and performance. Key standards include:

• ISO 15973 – Blind rivets with break pull mandrel
• ISO 15977 – Open-end blind rivets
• ISO 8749 – Pop rivets – Mechanical properties
• ASTM F468 – Nonferrous rivets for general use
• ANSI B18.1.1 – Small solid rivets
• DIN 7337 – Blind rivets
• NAS 1921-1940 – Aerospace flush rivets (National Aerospace Standard)
• GB/T 12615-2006 – Chinese standard for break mandrel blind rivets

Rivet Precise Selection Criteria and Matching Principles

For engineering procurement and site selection, follow these rules:

1. Material match: Choose rivet material compatible with base materials to avoid galvanic corrosion (e.g., aluminum rivet for aluminum sheets, steel for steel). Use stainless steel or Monel when joining dissimilar metals.
2. Grip range calculation: Total thickness of joined materials (including gaps) must fall within the rivet's grip range. Example: for 3mm + 2mm = 5mm total thickness, select a rivet with grip range 4-6mm.
3. Strength requirement: Check required shear and tensile loads. Use safety factor of 1.5-2 for static loads, 3-4 for dynamic. Refer to manufacturer's strength chart.
4. Hole preparation: Drill hole diameter = nominal rivet diameter + 0.1 to 0.2mm. For countersunk rivets, hole countersink depth must match head angle (100° for aerospace, 120° for general).
5. Setting tool compatibility: Blind rivets require specific nosepiece size. Ensure mandrel break load matches tool capacity.

Rivet Procurement Pitfalls and Avoiding Mistakes

Common mistakes when purchasing rivets:

• Ignoring grip range tolerances: Ordering standard length without measuring actual stack-up can cause insufficient clamp or mandrel protrusion. Always specify grip range, not just length.
• Overlooking coating: Uncoated steel rivets rust quickly. For outdoor or marine environments, require zinc plating (minimum 8μm), hot-dip galvanized, or stainless steel.
• Mixing hardness grades: Using too hard rivet (e.g. 304 stainless) on soft material (e.g. aluminum) can crack the base. Use same hardness or softer rivet.
• Neglecting head style: Countersunk rivets require precise countersink angle. Using wrong angle (e.g. 100° rivet in 120° hole) causes poor flushness and stress concentration.
• Blind rivet mandrel issues: Low-quality mandrels break at wrong force causing incomplete setting. Request mandrel break load certification per ISO 8749.

Rivet Usage and Maintenance Guide

Installation tips:

• Clean holes of burrs, oil, and debris before insertion.
• Use correct rivet gun pressure – too high damages workpiece, too low causes loose joint.
• For structural blind rivets, verify mandrel is fully pulled and breaks at designed point. Visually inspect shop head formation.
• Solid rivets require proper bucking bar support. The tail should expand to 1.5x original diameter approximately.

Maintenance and inspection:

• Regularly check for looseness or corrosion in critical joints (e.g., aircraft skin rivets require eddy current inspection).
• Replace rivets if head deformation, cracks, or mandrel voids appear.
• In marine environments, apply sealant under rivet head to prevent crevice corrosion.
• For temporary repairs, never reuse a pulled blind rivet – always install new ones.

Common Rivet Misconceptions

• Myth: Larger rivet always stronger. Reality: Oversized rivet may thin out surrounding material or cause hole distortion. Strength depends on material and proper installation, not just diameter.
• Myth: Blind rivets have same strength as solid rivets. Reality: Solid rivets typically have 30-50% higher shear strength than blind rivets of same diameter due to full material cross-section.
• Myth: Countersunk rivets are always flush. Reality: If countersink depth is wrong, the head may sit proud or recessed, both causing stress risers. Use depth stop tool.
• Myth: Aluminum rivets are only for light duty. Reality: High-strength aluminum alloys (e.g., 2117, 7050) are used in aircraft structures with tensile strengths exceeding 400 MPa.
• Myth: Riveting is a no-maintenance joint. Reality: Fatigue and corrosion can degrade riveted joints over time. Periodic inspection is essential for safety-critical applications.