... speed, saving cement, improving cement mobility and workability. FDN is a high range concrete admixture of concrete casting-in-place, prefabricating ... of nearly 1 square kilometer, our plant is focused on FDN-A, FDN-B, FDN-C series naphthalene sulfonate formaldehyde ... every employee's opinion, and wholeheartedly serving our customers is our belief. All colleagues of Shandong Wanshan Chemical Co., ...