5.Class labeled with 6 pressure levels: They are: Class 150; Class 300; Class 600; Class 900; Class 1500; Class 2500
6.Carbon steel flange of another layer of meaning is: according to the national standard dimensions, tolerances and other production of flange, different from the standard sizes not produced, also known as two standard flange piece flange (someone called non-standard method Lan is incorrect), usually some unscrupulous businesses will reduce flange thickness, the outer diameter of the two dimensions to achieve the purpose of saving material, as well as with scrap steel or scrap steel processing flange, usually this is the chemical composition of the steel and Mechanical properties of non-compliance of the waste or, worse, with black steel flange private steel production, steel making technology this private use of obsolete steelmaking can not guarantee the mechanical properties and weldability, there may not be time to use and pipe welding, or steel itself has cracks, holes and other leaks will go up after welding. So try to use the time of purchase flange steel flange.
7.Features and parameters: Eathu Carbon steel flanges close and reliable. It has two sealing surface, and valve sealing surface material widely used kinds of plastic, sealing, and can be completely sealed. Because carbon steel flanges have to wiping in opening and closing process, it can be used for media with suspended solid particles. Model Q41F - 16C Q41F - 25C ASTM A105 about 0.9% (standard is 1.05Max with decreasing carbon content can to 1.65% Max) As GB 16Mn content in about 1.3% (standard 1.2% to 1.6%), JIS S25C then it is relatively low at 0.6%.
8.Common Process: Production processes are forging, casting, plate rolling, plate cutting system and so on.
Where the highest price forging, plate products second, casting minimum product. On the quality, the forging of the best, rolled a second, casting the third. But forging caliber generally small.