Products + Tools

Fastening in soft materials presents unique challenges that require specialised solutions to ensure durability and reliability. For instance, materials such as plastics often experience issues with pull-out resistance, material deformation and thread stripping. This is where BBA’s specialised solutions including BCT rivet nuts can be used – maintaining structural integrity while minimising material damage.

As plastics continue to gain popularity due to their lightweight properties and cost-effectiveness, fastener manufacturers must develop innovative solutions to address the challenges of securing plastic components. Traditional fastening methods, originally designed for metals, often fail to provide adequate grip and long-term performance in plastic applications. To overcome these limitations, advanced fastening technologies have been developed to ensure strong and reliable joints in plastic materials.

Using a standard blind rivet nut in plastic presents several challenges, due to the inherent properties of the material. Unlike metals, plastics have lower strength and rigidity, making them prone to deformation when subjected to the compressive forces applied during installation. This deformation can weaken the connection, reducing the lifespan and effectiveness of the joint.

Additionally, plastics are susceptible to stress fractures and cracking when exposed to high pull-out forces. Standard rivet nuts, originally designed for metal applications, may create excessive stress concentrations around the hole, causing the fastener or surrounding plastic material to fail prematurely. These challenges necessitate the development of specialised fastening solutions that distribute forces evenly and provide strong, reliable performance.

To address these challenges, BCT rivet nuts from BBA Srl have been specifically engineered for use in plastics and composite materials. Unlike standard rivet nuts, which require the sheet material to trigger compression, BCT rivet nuts form at a predetermined location, helping to eliminate excess pressure on the plastic, preventing cracks and delamination during installation.

A key advantage of BCT rivet nuts is their minimal radial expansion, ensuring they do not overstress or damage plastic components. BBA highlights their bulge diameter is 40% larger than standard rivet nuts, allowing for better compensation of material tolerances and ensuring a secure grip even in plastics of varying thicknesses. The larger bulge also helps distribute pull-out forces more evenly, preventing concentrated stress points and increasing the overall strength of the connection.

Additionally, BCT rivet nuts are made from stronger materials with a tensile strength of 480 MPa, compared to the standard 300 MPa. This higher strength improves durability and resistance to mechanical stress, making the rivet nuts a reliable fastening solution for plastics and composites – where standard options may not perform adequately. 

In addition, BBA also supplies nail nuts, which provide another effective solution for fastening plastics by incorporating ‘teeth’ under the head to help eliminate the common issue of rotation or slippage under torque – with the softness of plastic causing traditional fasteners to shift or loosen over time, reducing joint stability. The ‘teeth’ design enables superior torque resistance and prevents unwanted movement, which BBA reports significantly increases torque resistance by 130% compared to standard rivet nuts to ensure a secure, long-lasting connection.

“This additional grip is particularly valuable in applications where vibration or repeated stress is a concern,” highlights BBA. “By preventing unwanted movement, nail nuts improve fastening reliability and product longevity.”

The company concludes: “BBA’s focus on quality, technical expertise and continuous improvement enables it to remain as a trusted partner for industries worldwide, delivering high-quality engineered fasteners that enhance product reliability and manufacturing efficiency.”