Edge Crush Test

Edge Crush Test (ECT) is an important metric in the corrugated box industry for measuring the compressive strength of cardboard. It is mainly used to evaluate the load-bearing capacity of cartons during stacking and transportation. The test method is: place a corrugated board specimen vertically between two platens, apply pressure along the flute direction until the board crushes, and record the maximum force, typically in lb/in or N/m. The higher the ECT value, the better the carton's compressive strength. Use cases include: confirming carton procurement specifications, transport packaging design, and compliance verification for export product packaging (e.g., Amazon ISTA standards). Notes: ECT differs from Bursting Strength—the former simulates vertical compression, while the latter simulates puncture; ECT is also affected by board moisture content and flute type. It is often used interchangeably with 'edge crush strength,' but strictly speaking, ECT is the test method and edge crush strength is the result value. In foreign trade contracts, the ECT value, test standard (e.g., TAPPI T-811 or GB/T 6546), and unit should be clearly specified to avoid disputes caused by standard differences.