Threaded flange is to process the inner hole of the flange into pipe threads. The connection method between the flange and the pipeline is not by welding, but by threaded connection, that is, the inner hole of the flange is threaded, and the pipe on the pipeline is also turned. Make the corresponding thread, and then match the connection.

The threaded flange adopts the following threads: 55° tapered internal thread Rc specified in GB 7306, 55° cylindrical internal thread RP specified in GB 7306, and 60° tapered internal thread NPT specified in GB/T 12716 (other: PT is BSPT, which is 55 °Sealed tapered pipe thread, belongs to the Wyeth thread family, mostly used in Europe and the Commonwealth of Nations, often used in the water and gas pipe industry, taper 1:16, national standard GB/T7306-2000, domestically called ZG; ZG tapered pipe thread, ZG It is the old code, the new code R is the tapered pipe external thread, the pattern is Rc tapered internal thread; G is the 55° non-threaded sealed pipe thread, which belongs to the Wyeth thread family. The mark is G for cylindrical thread. National standards can be found in GB/T7307-2001 ).

Threaded flanges are not high-pressure flanges, and are suitable for low pressure, such as engineering construction, air-conditioning water systems, etc., and can be used safely. Threaded flange is a kind of threaded product that is often referred to. For example, the pipe fittings used in the house on the tap water are threaded. They are often used in engineering construction. They have the advantages of convenient on-site installation, convenient maintenance, and no need for welding. It can be used on pipelines that do not allow welding, are difficult to weld, or have poor welding performance. Threaded flanges are not high-pressure flanges. Standard threaded flanges are flanges with necks. Except that the flanges are also different, other sizes of necked flat welding flanges are the same as socket welding flanges. One end of the threaded flange is connected with the pipe thread. , The other end is connected with other flanges, flange covers, equipment, valves, etc.

The sealing surfaces of threaded flanges have only two types, full-plane and raised surface. my country's threaded flanges are only suitable for inch pipe series. For the threading of the inner pipe of the threaded flange, the end of the steel pipe after tightening should be close to but not beyond the sealing surface of the flange piece. When the threaded flange adopts the 60-degree tapered pipe thread specified in GB/T12716, the outer diameter of the steel pipe for the DN65 flange should be 73mm; the outer diameter of the steel pipe for the DN125 flange should be 141.3mm. When using the 55-degree pipe thread specified in GB7306, the outer diameter of the steel pipe for the DN150 flange should be 165.1mm.

Threaded flange is a kind of non-welded flange, in which the inner hole of the flange is processed into pipe threads and connected with threaded pipes. Taking into account the structural characteristics of threaded flanges, it is not suitable for flammable, explosive and hazardous occasions. The threaded flange is suitable for pressure 0.6-4.0Mpa and diameter DN10-DN150. Except for the inner diameter thread size of the threaded flange, the other dimensions are the same as the neck flat welding flange