Qualitätsmanagement Quality management system ISO-9001.2015-Quality-management-system-2 Produktzertifikate Kiwa-Zertifikat K602BRL-K602-Valves-and-other-accessories-for-drinking-water-transport-and-distribution-systems-2 Kiwa-Zertifikat K772BRL-K772-Ductile-iron-pipes-and-fittings-for-the-transport-of-drinking-water-1 Kiwa-Zertifikat K773BRL-K773-Ductile-iron-fittings-for-piping-systems-of-PVC-U-or-PE-drinking-water-1 Kiwa-Zertifikat K775BRL-K775-Ductile-cast-iron-joints-for-pipes-of-nodular-cast-iron-steel-PVC-U-or-PE-1 Powder epoxy coating GSK RAL-GZ-662-2RAL-GZ-662-2-Special-Quality-and-Test-Regulations-for-Processes-1 RAL-GZ-662-3RAL-GZ-662-3-Special-Quality-and-Test-Regulations-for-Valves-and-Fittings-with-Powder-Coating-Products-1 Die Kolk GmbH ist ein Tochterunternehmen der Kolk B.V. Niederlande.