Does the cast iron have size 250? What's the performance?
Ductile iron does not have size 250. Ductile iron is the beginning of QT, QT400-15, QT450-10, QT500-7 is the general use of nodular cast iron brand. Nodular cast iron welding can be determined, this should be in some high strength cast iron equipment used more, the tensile strength of normally ductile cast iron welding in welding is higher, is worse than the grey cast iron, it is actually very difficult to distinguish with the naked eye is ductile iron or cast iron the iron in the repair equipment, we usually use WE777 special cast iron electrode universal wide welding, but it is only for maintenance use, the effect is really good, reducing the risk of cracking and high strength welding rod matching to ensure the strength of welding seam.
1, cast iron because of low melting point, casting process performance is good, because it has been widely used.2, the relative gray iron ductile iron, have higher tensile strength and impact toughness, which has better mechanical performance.
You should be the casting grade or material, if it is ductile iron, said generally between QT400-15 or QT700-2 different indicators, said in front of the tensile strength, the elongation rate refers to the back, China is now the lowest grade of nodular cast iron material is QT400-15, such as QT250.In addition, the number 250 you refer to may also be a code name for ductile iron parts, such as 200, 300, etc., which are manufactured by the factory as required by the project.Gray iron, which has a 250 brand, is generally referred to as HT250, but it is not ductile iron.The machine on the ductile iron and gray iron are used, but generally not made of grey cast iron gear
