The flat welding flange is a kind of flange that inserts the pipe into the inner ring of the flange and welds it. Flat welding flanges are divided into plate flat welding flanges PL and necked flat welding flanges SO. The difference between the flat welding flange with neck and the flat welding flange without neck is that the flat welding flange with neck is one more place in the pipeline welding part than the flat welding flange without neck. The flange is also the flat flange. The flat welding flange only needs to be welded on one side, and the flat welding is relatively easy to weld. Because the pipe and the flange are straight, the pipe will not be inclined.
Flat welding flanges are convenient to obtain materials, simple to manufacture, low cost flange cover, and widely used; but their rigidity is poor, so they should not be used in chemical process piping systems that require supply and demand, flammability, explosion and high vacuum degree. Extremely damaged place. The sealing surface types are flat and raised.
Precautions for the use of flat welding flanges:
1. The flat welding flange should be cut into strips along the rolling direction of the steel, butt-welded into a ring shape by bending, and the surface of the steel should form a cylindrical surface of the ring. In the production of flat welding flanges, steel plates shall not be directly machined into neck flanges, and certain processes shall be used for manufacturing and processing.
2. The steel plate of the flat welding flange should be ultrasonically inspected without delamination defects to ensure good quality and performance problems. It should be produced and inspected according to certain quality requirements to ensure that the steel plates produced and used have no quality problems.
