Nylon fasteners & rivets: How environmental factors impact extraction force
Extraction force is the mechanical force required to disengage a fastener from its mating component. In nylon fasteners and rivets, extraction force varies. This is due to the polymer’s modulus, dimensional stability, and surface friction change under different environmental conditions. In this guide, we’ll take a closer look, covering:
Environmental influences on retention performance
Testing nylon 6 and nylon 6/6
Type of rivets affected by environmental factors
What's the impact in tensile strengths for nylon rivets?
Benefits of nylon fasteners and rivets in extreme conditions
Industries and applications
Environmental influences on retention performance
The extraction force of nylon fasteners and rivets shifts with service conditions. Elevated temperatures soften the material and reduce dimensional stability, which can loosen the fit and lower the force required for removal.
Cold conditions make nylon harder but also more brittle, which can lead to cracking when force is applied. In damp or humid environments, the material absorbs moisture, swelling slightly and shifting the fit. Over time this also knocks down its strength. Sunlight, especially over long periods, breaks down the polymer, so parts lose toughness and don’t hold as well.
Oils, fuels, and certain cleaning solvents can attack the nylon itself, leaving it weaker and easier to pull out. In practice, that means a part that holds fine in the lab may fail early in the field if the environment isn’t considered up front.
Browse our range of nylon rivets
Testing Nylon 6 and nylon 6/6
These two nylons are commonly used to make fasteners and rivets. The nylon fastener you choose should be based on the environmental factors that could affect your application. Our experts created a guide for you to choose the nylon materials for your applications: The differences between nylon 6 and nylon 6/6.
When specifying nylon fasteners, account for the effect of moisture absorption in nylon 6 and nylon 6/6 on tensile strength and ductility. Changes in storage conditions or environmental exposure can alter these properties and lead to performance issues. These effects are often seen in extraction force testing, where differences in moisture content and temperature produce notable changes in results.
Moisture content impact on extraction force
Moisture absorption is a key variable in nylon’s mechanical performance, and its effect becomes clear when we examine extraction force test data. Graph 1 and Chart 1 compare nylon 6 and nylon 6/6 fasteners at different moisture levels and temperatures, using 72 °F and 50% relative humidity as the baseline. Testing the same fastener in the same hole, with only moisture content changed, yielded markedly different pull force results. In the most extreme case, a part at 0.67% moisture produced an extraction force 224% higher than the same part at 6.74% moisture.
Such variation can occur when production and installation environments differ in humidity, and if not addressed during design, may lead to reduced holding strength and premature failure.
Type of rivets affected by environmental factors
Nylon is a strong and versatile material for rivets, but its mechanical properties are sensitive to environmental conditions.
Nylon keyhole clips
Key hole clips feature an internal profile shaped to allow greater collapse during installation, enabling quick assembly with finger pressure. A tapered, bullet-style tip assists in guiding the clip smoothly into the panel opening.
Made of nylon 6/6, they insulate against electricity and stand up well to vibration, wear, and corrosion. Rated UL94 V2.
Push-in rivets – snap lock pins
A snap lock pin, sometimes called a push-in fastener pin, provides a quick, secure joint without the need for screws or nuts, making it well-suited for applications where threaded hardware is impractical.
These pins are commonly used to hold connectors on printed circuit boards prior to soldering but can also function as general-purpose push-fit panel fasteners. To install, push the pin into the panel hole until it seats. Arrowhead versions grip more firmly and work with a wider range of panel thicknesses. Once fitted, the pin stays in place and handles vibration, wear, and corrosion well. Nylon 6/6. Rated UL94 V2.
You might be interested in our Guide to snap rivets.
Plastic screw rivets
Plastic screw rivets are quick-release fasteners designed for security panels and components that require rapid replacement. They can be installed, tightened, loosened, and removed with a standard cross-head screwdriver.
The range includes multiple material options, with nylon 6 and nylon 6/6 versions featuring a cross drive for straightforward assembly and removal. High-strength variants are available in impact-modified nylon with a choice of pin material. Fast and easy to fit, these nylon rivets offer strength and versatility, with head styles including round, truss, and mushroom, and drive types in both crossed and slotted formats.
Push-in rivets – push-in fasteners
Plastic rivets offer a quick, simple way to join two components securely while maintaining a clean appearance.
Nylon versions are strong and durable, making them suitable for connecting panels, light sheet metal, insulating boards, circuit boards, and other thin or lightweight materials. The legs are designed to compress during insertion and then expand, locking into pre-punched holes. A large head makes them easier to handle during assembly, and they can be removed and reused, offering a cost-effective fastening option.
This range is designed to hold firmly in pre-punched panels and withstand vibration, wear, and corrosion. Nylon 6/6.
Our experts explain more in our guide, What is a push-in rivet?
What's the impact in tensile strengths for nylon rivets?
Lower moisture content in nylon increases tensile strength and can raise extraction forces, but it also reduces ductility and impact resistance. Many nylon fasteners rely on a degree of flexibility to function correctly.
For example, the limbs of a fir-tree fastener must flex to pass through a mounting hole and then return to shape on the opposite side of the panel to hold it in place, as shown here. For this reason, extremely low moisture levels are generally not optimal in application.
Reduced impact strength under these conditions can also increase the risk of premature or unexpected failure if not addressed during the design stage.
It might seem intuitive that a significant increase in test temperature would reduce extraction force. In practice, most moisture levels showed a higher coefficient of variation (CV) compared with the 72 °F control. The trade-off is less predictability in extraction force, as shown by the CV values in Graph 2 below.
Benefits of nylon fasteners and rivets in extreme conditions
Nylon fasteners can perform well in challenging environments if the material grade and expected conditions are considered from the outset. Our test data shows that both nylon 6 and nylon 6/6 maintain useful retention strength across a range of temperatures and moisture levels, but performance is strongly influenced by those variables.
1. Matching grade to application
Nylon 6 and nylon 6/6 react differently to changes in moisture content and temperature. Selecting the grade that best suits the installation and service conditions helps balance strength, flexibility, and consistency.
2. High holding force at low moisture
In our tests, the highest extraction forces were measured in the driest samples, up to 224% higher than the most saturated samples tested. This is an advantage where maximum grip is needed, but the reduced ductility at low moisture should be considered in the design.
3. Stability in controlled conditions
At the baseline of 72 °F and 50% RH, our results were consistent, making this a good reference point for applications with minimal environmental fluctuation.
4. Retention under heat
Even at elevated temperatures, we found that nylon fasteners maintained a significant level of holding force. This allows their use in hotter environments, provided the design accounts for increased variation in performance under these conditions.
Takeaway
Nylon fasteners are suitable for extreme environments when the grade, moisture content, and likely temperature range are accounted for before installation. Testing under representative service conditions remains the best way to ensure performance over the life of the product.
Industries and applications
Nylon fasteners and rivets are used where a strong, lightweight, and non-corrosive connection is needed. They’re common in assemblies that must be installed quickly, maintained easily, or insulated electrically.
We recommend you also check out our experts’ Guide to fasteners for buyers.
● Electronics and Electrical Equipment – Securing PCBs, insulating components, and mounting covers or enclosures without introducing conductive paths.
● Automotive – Interior trim panels, cable management, and lightweight fastening where vibration resistance is needed.
● Appliances – Mounting panels, guards, and insulation boards where moisture resistance and non-corrosive performance are essential.
● HVAC Systems – Attaching duct panels, grills, and covers, withstanding temperature swings and vibration.
● Telecommunications – Equipment housings, cable guides, and internal component fastening in both indoor and outdoor enclosures.
● Furniture and Fixtures – Joining lightweight panels, decorative trims, and components without visible fastener heads.
● Marine and Outdoor Equipment – Applications where resistance to salt spray and weathering is required, provided UV protection is addressed.
If you’re wondering how to use nylon rivets, the process is simple: align the holes, insert the rivet, and push or screw it in until it’s secure.
Download free CADs and try before you buy
Free CADs are available for most solutions, which you can download. You can also request free samples to make sure you’ve chosen exactly what you need. If you’re not quite sure which nylon rivets or nylon fasteners will work best for your application, our experts are always happy to advise you.
Whatever your requirements, you can depend on fast dispatch.
Questions?
Email us at sales@essentracomponents.co.uk or speak to one of ourexperts for further information on the ideal solution for your application 0345 528 0474.