J-кольцо, узкий зазор, EN

J-Ring Narrow Gap, EN is a professional stainless-steel apparatus designed to evaluate the passing ability and flow behavior of self-compacting concrete (SCC) through narrow openings. The smooth steel rods arranged on a circular support ring create a reinforcement-like obstruction geometry and are fixed in a narrow-gap configuration to ensure identical passage conditions in every setup. The apparatus is configured to meet EN narrow-gap requirements with a 300 mm ring diameter and a total of 16 rods of Ø18 mm. The system is designed for use together with an EN-compliant stainless-steel base plate and slump cone. Engraved positioning circles on the plate assist in rapid centering of both the apparatus and the cone.