The surface of PL flange (plate flange) is a flat with circular disk. Flange plat is welded onto the end of a steel pipe, to be bolted to another pipe. Due to the good comprehensive performance of steel plate flange, it is widely used in chemical engineering, construction, water supply, drainage, petroleum, light and heavy industry, refrigeration, sanitation, plumbing, fire protection, power, aerospace, shipbuilding and other basic projects.
For the easy-obtaining production material and simple-manufacturing process of the flat face blind flange, people use it in many fields stated above. Of course, the main factor should be very low cost. But PL flange has a vivid disadvantage, its poor rigidity, so it should not be used in chemical process piping systems and high and extremely hazardous occasions with supply and demand, flammable, explosive and high vacuum requirements. Usually, as we find in the markets, there are two major sealing surface types, flat and protruding.
Welding form of stainless steel plate flange: PL flange is inserted into the flange to be welded.
Material of flat welding flange: besides stainless steel, these materials also common, 201,304.316.316L.0Cr18Ni9.321.202, carbon steel, 20 #, 20G, and alloy steel.
The pressure mark specified in PL flange is divided into PN series and Class series.
PN series: PN2.5; PN6; PN10; PN16; PN25; PN40; PN63; PN100; PN160; PN250; PN320; PN400
Class series: Class 150; Class 300; Class 600; Class 900; Class 1500; Class 2500
There are several types of sealing surface of the flat welding flange:
1, Concave-convex surface (MFM) DN1300 ~ 3000 DN300 ~ 3000 DN400 ~ 2000 DN300 ~ 800
2, Tongue and groove surface (TG) DN1300 ~ 3000 DN300 ~ 3000 DN300 ~ 3000 DN300 ~ 800
3, Full Plane (FF) DN300 ~ 3000 DN300 ~ 3000 DN300 ~ 3000 DN300 ~ 800