1. Material: Stainless Steel 316L, etc
2. Size: 2" (DN50)
3. Standard: BS, etc
4. Pressure: PN6, PN10, PN16, PN25, PN40, PN64, etc
BS 4504: British Standard BS 4504 : Section 3.1 : 1989 - Circular Flanges for Pipes, Valves and Fittings (PN Designated), Specification for Steel Flanges. This covers flanges in nominal pressure ranges PN 2.5 to PN 40 and nominal sizes up to DN 4000 (see table below). BS 4504 substantially agrees with ISO 7005-1 : 1992 (E) Part 1 : Steel Flanges.
BS 4504 : 1969 is still commonly used. This older standard allows for manufacture from bar, whereas the latest standard specifies that forging or plate are to be used, which can be significantly more expensive. There are minor differences in dimensions between the two versions. The following tables are based on the later version.
A bs 4504 316l 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.
Plate flanges are fabricated mainly from quality mill steel plates. They are similar to slip on flange but without the hub and also require two fillet welds. Mostly the plate flanges are produced in accordance with DIN, JIS, UNI, BS or GOST standards.
When building a pipeline, the length of the pipes used are not always known. By manufacturing the pipes separate from the plate flanges, the welders can cut the pipes to length and weld a plate flanges 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.
