Direct welding of flat welding flange
Flat welding and Weld neck flanges are the welders for the connection of flange and pipeline. Flat welding flange only needs one side welding, but does not need to weld the inner opening of pipeline and the connection of flange. The welding and installation of flange welding need double-sided welding of flange. Therefore, flat welding flange is generally used for medium and low pressure pipeline, and welding flange is used for medium and high pressure pipeline connection, and the welding flange is generally at least 2.5 psi, Butt welding is used to reduce stress concentration. Generally speaking, welding flange is neck flange, also known as threaded joint flange. Therefore, the installation cost, labor cost and auxiliary material cost of welding flange are relatively high. Because there is one more process, the production and use of flange plate welding have certain technical requirements and parameters, which are produced and processed according to certain methods and methods
1. The steel plate used in the production of flat welding flange shall be subject to ultrasonic flaw detection without delamination defect, so as to ensure good quality and performance. And according to certain quality requirements for production and inspection, to ensure that the production and use of steel plate without quality problems;
2. The steel should be cut into strips along the rolling direction and welded into a ring by bending. The steel surface should form a cylindrical surface. The steel plate should not be directly processed into a neck flange. The flange should be manufactured and processed by a certain process. The welding of welding flange needs a certain welding process, and the butt weld of the ring should adopt full penetration welding;
3. The ring butt weld shall be subject to post weld heat treatment and 100% radiography or ultrasonic testing. The radiographic testing shall meet the secondary requirements of JB4730, the ultrasonic testing shall meet the primary requirements of JB4730. The welding flange shall be produced and processed according to certain welding standards and processes, and shall meet the corresponding national production standards and requirements. The flat welding flange is the most common plate-shaped part in the pipeline engineering, and the flange is used in pairs.
previous_pageButt welding flange connection and construction requirements
next_pageProduction Process Of Blind Flange