This article gives an introduction to commonly used butterfly valve materials. For the butterfly valve, we should already have a certain understanding, there are many types of butterfly valves, according to the different types of connection, they can be divided into wafer butterfly valves and flanged butterfly valves.According to the sealing material, it can be divided into soft sealing butterfly valve and metal hard seal butterfly valve;Depending on the driving mode, it can be divided into handle butterfly valve, worm gear operated butterfly valve, pneumatic butterfly valve, electric butterfly valve and so on.What are the commonly used butterfly valve materials?
Commonly used butterfly valve materials mainly include cast iron, cast steel, and stainless steel. Each kind of material can be subdivided further. Now we will introduce the material of these three types of butterfly valves.
The first category: cast iron
Subdivided into cast iron, there are gray cast iron, malleable iron, ductile iron, nickel cast iron four. This article mainly introduces the two kinds of cast iron materials that are manufactured by Bundor Valve, including gray cast iron and ductile cast iron.
Gray cast iron is a cast iron with flake graphite, which is called gray cast iron because the fracture is dark gray when fractured. Gray cast iron is currently the most widely used cast iron, and its output accounts for more than 80% of the total output of cast iron.
Gray cast iron casting properties, cutting performance, wear resistance are very good. Its disadvantages are the low strength, ductility and toughness compared with other cast irons.
The use of gray cast iron as a butterfly valve material is generally suitable for mediums with weak acid and weak bases such as water and air, and is not suitable for use in pipelines containing perchloric acid and nitric acid.
Ductile cast iron is a kind of high-strength cast iron material. Its strength, toughness and wear resistance are very high. Its comprehensive performance is close to that of steel. At present, the scope of application of ductile iron is second only to gray cast iron. We often say that “iron-based steel” refers to ductile iron.
With ductile iron as the butterfly valve material, it has a certain degree of corrosion resistance, performance is much higher than the gray cast iron material butterfly valve, and its applicable medium includes steam, general properties of gas and oil and so on.
The third category: stainless steel
Stainless steel refers to steels resistant to weak corrosive media such as air, steam, and water, and chemically etched media such as acids, alkalis, and salts, and also called stainless acid-resistant steels.
Usually stainless steel butterfly valve material, performance is the best, can be applied to more severe working conditions, in some ultra-high temperature, ultra-low temperature, acid and alkali corrosive medium pipe use, while stainless steel butterfly valve hardness is stronger, more Wear resistance, longest service life.
The above is the commonly used material of the butterfly valve. Usually, according to the price, the price of the stainless steel butterfly valve is the highest, and the gray cast iron is the cheapest.