Blind disks are officially known as Flange covers, sometimes referred to as blind flanges or pipe plugs. They are flanges without holes used to seal pipe openings. The function they serve is similar to that of caps and pipe ends, but whereas blind plate sealing is a removable sealing device, the sealing of caps is not intended to be reopened. The sealing surface comes in various forms, including flat, convex, concave-convex, tenon-mortise, and ring-connection surfaces. Materials include carbon steel, stainless steel, alloy steel, copper, aluminum, PVC, and PPR.
