Flange, also known as a flange disk or raised rim. A flange is a component that connects shafts together, used for pipe-end connections; there are also flanges used on equipment inlets and outlets for connecting two pieces of equipment, such as a reducer flange. Flange connection or flange joint refers to a removable connection consisting of a flange, a gasket, and bolts, which form a combined sealing structure. Pipe flanges refer to flanges used for piping in equipment installations, while those on equipment refer to the equipment's inlets and outlets. Flanges have holes for bolts, which tighten the flanges together. The spaces between flanges are sealed with a gasket. Flanges come in threaded (screwed) connections,焊接 (welded) flanges, and clamp flanges. Flanges are used in pairs; low-pressure pipes can use threaded flanges, while pipes above four kilograms of pressure use焊接 flanges. A sealant is added between the two flange disks, and then bolts are tightened. Flanges of different pressures have different thicknesses and require different bolts. In the connection of equipment like pumps and valves to pipes, the local parts of these devices are also shaped as corresponding flanges and are called flange connections. Any connection piece that uses bolts to connect two flat surfaces and seal them is generally called a "flange," such as the connections in ventilation pipes. These types of parts can be referred to as "flange-like components." However, such connections are only parts of a single device, like the connection between a flange and a pump, so it's not appropriate to call the pump a "flange-like component." Smaller items like valves can be referred to as "flange-like components."