Plate Flanges, which are of wide variety, are manufactured mainly from plates. They are conforming to national & international standards and they are hubless. Plate flanges are produced from quality mill plates. Before cutting pieces out of plates, each plate is checked for serious laminations.
Plate flange is also named plain flange, flat flange and slip on flange etc. A plate flange is a flat, circular disk that is welded onto the end of a pipe and allows it to be bolted to another pipe. Typically used in fuel and water pipelines, the two plate flanges will be bolted together with a gasket in between them. The plate flange will have bolt holes all around the perimeter and will be used to create junctions, tees and joints.
When building a pipeline, the length of the pipes used are not always known. By manufacturing the pipe separate from the plate flange, the welders can cut the pipe to length and weld a plate flange in place to join the pipes at any needed length. The plates can also be welded to the pipe on a slight bias, allowing two pipes to be joined that may not be precisely lined up.
Plate flange designs are uniform in any given size regardless of materials used to create them. This allows a 6-inch (15 cm) black pipe flange to mate perfectly with a 6-inch stainless steel flange. The plate flanges will have a serrated finish on the inside mating surface, which allows the plate to seat into the gasket material. This ensures a perfect seal between two joining pipes.