Common materials are cast carbon steel grade WCB, forgings A105, or Q235B, A3, 10#, #20 steel, 16 manganese, 45 steel, Q345B, etc.
Usually to prevent rusting flange surface electroplating layer (yellow zinc, white zinc, etc.), or brush anti-rust oil and spray anti-rust paint treatment.
Ministry of Machinery standards JB/T81-94, JB/T79.4-94, JB/T83-94
Chemical Ministry Standard HG20593-97 / HG20617-97
National Standard GB/T9119-2010
Another layer of carbon steel flange meaning: in accordance with the national standard requirements of the size, tolerance range, etc.
production of flange plate, as distinguished from the standard size of the production of flange piece also known as two standard flange (some people called non-standard flange is incorrect), usually some unscrupulous businessmen will reduce the flange thickness,
outer diameter of the two dimensions to achieve the purpose of saving materials, there are scrap steel or edge steel processing flange, usually this steel Is the chemical composition and mechanical properties of the scrap does not meet the standard, and even more with the black steel mill private steel production flange, the use of this private steel refining technology is old can not guarantee the mechanical properties and welding properties, the use of steel may not be able to weld with the steel pipe, or the steel itself has cracks, porosity, etc. after welding up will also leak. So try to use carbon steel flanges when buying flanges.
Carbon steel flange is tight and reliable. It has two sealing surfaces, and the current ball valve sealing surface materials are widely used in a variety of plastics, good sealing, can achieve a complete seal. As the carbon steel flange has wipability in the opening and closing process, it can be used in media with suspended solid particles. Model Q41F–16C Q41F–25C American standard A105 about 0.9% (standard is 1.05Max with decreasing carbon content can be up to 1.65%Max) as for the national standard 16Mn content is about 1.3% (standard 1.2% to 1.6%) Japanese standard S25C words are lower in 0.6% or less.
Production processes are forging, casting, medium plate coiling, medium plate cutting and so on.
Forging is the most expensive, plate products are the second most expensive and casting is the least expensive. In terms of quality, forged is the best, rolled the second, and cast the third most. However, forgings are generally smaller in calibre.
(1) According to the purpose, carbon steel can be divided into carbon structural steel, carbon tool steel and free cutting structural steel. Carbon structural steel can be divided into engineering construction steel and machine manufacturing structural steel;
(2) According to the smelting method, it can be divided into open hearth steel and converter steel;
(3) According to deoxidation method, it can be divided into boiling steel (f), killed steel (z), semi killed steel (b) and special killed steel (TZ);
(4) According to the carbon content, carbon steel can be divided into low carbon steel (WC ≤ 0.25%), medium carbon steel (WC 0.25% – 0.6%) and high carbon steel (WC > 0.6%);
(5) According to the quality of steel, carbon steel can be divided into ordinary carbon steel (higher phosphorus and sulfur), high-quality carbon steel (lower phosphorus and sulfur), high-grade high-quality steel (lower phosphorus and sulfur) and special grade high-quality steel.
Note: generally, the higher the carbon content in carbon steel, the greater the hardness and strength, but the lower the plasticity.
Brief analysis on the difference between ordinary carbon steel and stainless steel
According to the quality of steel, carbon steel can be divided into ordinary carbon steel (higher phosphorus and sulfur), high-quality carbon steel (lower phosphorus and sulfur), high-grade high-quality steel (lower phosphorus and sulfur) and special grade high-quality steel.