Reliable Structural Bonding in Rail Transit Equipment Using Araldite® 2014-2

A European manufacturer of rail transit equipment encountered challenges when assembling support brackets for auxiliary systems on a new train model. Traditional mechanical fastening methods—such as riveting and bolting—led to fatigue cracking in metal components due to constant vibration, and drilling holes compromised the base material’s structural integrity. Moreover, the brackets are continuously exposed to high humidity, temperature fluctuations, and lubricant/oil contamination, demanding exceptional long-term durability from the joining solution.

The engineering team selected Araldite® 2014-2, a two-component epoxy structural adhesive from Huntsman Advanced Materials, as the primary bonding solution. Key advantages included:

• Room-temperature curing—eliminating the need for ovens and enabling use in both production lines and field maintenance;
• Thixotropic, non-sag paste formulation capable of gap-filling up to 5 mm, accommodating typical manufacturing tolerances;
• High-strength adhesion to sandblasted aluminum and stainless steel (lap shear strength >14 MPa);
• Excellent resistance to water, lubricating oils, and mild acids—retaining bond integrity after 90 days of immersion in 90°C water and lubricants, as confirmed by ISO 4587 testing per the TDS.

After implementation, the bonded brackets exhibited improved overall stiffness and more uniform stress distribution, significantly reducing the risk of vibration-induced fatigue failure. The elimination of drilling and mechanical fastening steps increased assembly efficiency by approximately 20%. After two years of in-service monitoring, no debonding, cracking, or performance degradation was observed. The solution also aligns with basic material requirements of rail industry standards such as EN 45545 regarding fire behavior (note: full compliance requires system-level evaluation).