Evaluating Slow Crack Growth: Testron Groupโs Notched Constant Ligament Stress (NCLS) Testing Solutions
The TT-NCLS Notched Constant Ligament Stress Tester by Testron Group is a specialized laboratory instrument engineered to assess the resistance of high-density polyethylene (HDPE) resins, geomembranes, and corrugated drainage pipes to slow crack growth (SCG) under accelerated thermal and chemical conditions. Designed to simulate real-world environmental stresses, the multi-station system subjects precisely notched dumbbell specimens to a constant mechanical load while submerged in a surfactant reagent solution held at an elevated temperature. Testron's unit features automated pneumatic loading and unloading, an integrated load calculation tool to minimize setup errors, high-precision liquid level sensors, and automatic power-loss data protection to maintain test continuity during long-term evaluations. Manufactured with corrosion-resistant materials like 316L stainless steel and PTFE, the TT-NCLS allows quality assurance teams to perform brittle transition time measurements in full compliance with key industry benchmarks, including ASTM F2136 and ASTM D5397.















