The main functions of butt welding flanges are divided into the following categories:
- 1. In case of pipeline failure, it is easy to disassemble and test.
- 2. Connect the pipeline and keep the pipeline in good sealing performance;
- 3. If there is a problem in a certain section of pipeline, it is convenient to replace a certain section of pipeline.
Butt welding flanges have certain technical requirements and parameters in production and use, and are manufactured and processed in certain ways and methods:
- 1. The butt weld of the ring shall be subject to post weld heat treatment and 100% radiographic or ultrasonic flaw detection. The radiographic flaw detection shall meet the class II requirements of JB4730 and the ultrasonic flaw detection shall meet the class I requirements of JB4730. Butt welding flanges are produced and processed according to certain welding standards and technologies, which meet the corresponding national production standards and requirements.
- 2. The steel plates for butt welding flanges shall be subject to ultrasonic flaw detection without layering defects to ensure good quality and performance. They shall be produced and inspected according to certain quality requirements to ensure that the steel plates produced and used are free of quality problems;
- 3. It shall be cut into strips along the rolling direction of the steel, bent and butt welded into a circular ring, and the surface of the steel shall form a cylindrical surface of the ring. It is not allowed to directly machine the steel plate into the flange with neck during the production of butt flange, and a certain process shall be adopted for manufacturing and processing.
Butt welding flange can greatly save space and reduce weight, and it can also ensure that there is no leakage at the joint, with very good sealing performance. The reason why the size of the butt welding flange is reduced is that the diameter of the seal is reduced, which will reduce the section of the sealing surface. Secondly, the flange gasket has been replaced by the sealing ring to ensure the matching of the sealing surface.
In this way, only a small amount of pressure is required to press the cover tightly. With the decrease of the required pressure, the size and the required number of bolts will be reduced accordingly, so a butt welding flange with small volume and light weight finally appears. Therefore, butt welding flange is a kind of comparative flange, which reduces the burden of quality and space, and plays an important role in industry.
Butt welding flanges are often used when the medium temperature and pressure are not high and the medium is highly corrosive. When the medium is highly corrosive. Rare integral flanges are butt welding flanges and butt welding flanges. Flanged fittings are fittings with flanges (lugs or adapters). It can be cast, and the butt welding flange is mainly a part for connecting pipes with each other. According to the structural type. It can also be formed by threaded connection or welding. Flange connection refers to a pair of flanges, a gasket and several bolts and nuts.
The forging of butt welding flange can be divided into free forging, upsetting, extrusion, die forging, closed die forging and closed upsetting. The forging of butt welding flange can be divided into free forging, upsetting, extrusion, die forging, closed die forging and closed upsetting. Because there is no flash in closed die forging and closed upsetting, the material handling rate is high. Finish machining of large forgings can be roughly completed with one or several processes. Because there is no flash, the stress area of forgings will be eliminated, and the required load will also be eliminated. However, the blank shall not be completely restricted. Therefore, the volume of blank, the relative position of forging die and the measurement of forgings shall be strictly controlled.