JIS Slip-on Flanges for sale The looper flange is the movable flange piece, which is generally matched with the water supply and drainage fittings (the most common on the expansion joint). The equipment is bolted. It is generally used on pipes. In that case, loosening the bolts can rotate the pipes on both sides, and then tightening them can make it easier to disassemble and assemble the pipes. The looper flange is to use flanging, steel ring, etc. to put the flange on the pipe end, and the flange can move on the pipe end. The steel ring or flange is the sealing surface, and the function of the flange is to compress them. It can be seen that the looper flange is not in contact with the medium due to being blocked by the steel ring or flanging. Because the flange is movable and not directly connected to the pipeline, it is called a loose flange, and there is another way of saying it is a loose flange. FAQ What is the difference between RF flange and FF flange? Flat face (FF) flanges are similar to RF flanges, but they do not have the raised areas of RF flanges. Instead, the entire surface is flat. This means that gaskets used with FF flanges are in full contact with the entire surface where both flanges mate. What is the difference between A series and B series flanges? A-series flanges are heavier, thicker and cost more, while B-series flanges have more bolt holes and are less expensive than A-series. API605 flanges and B series flanges are the same thing.JIS Slip-on Flanges for sale website:http://www.huashuoflange.com/slip-on-flanges/jis-slip-on-flanges/