Valve body material description
1. Gray cast iron
Gray cast iron valve is widely used in various fields of industry because of its low price and wide application range. They are usually used in the medium of water, steam, oil and gas, and are widely used in chemical industry, printing and dyeing, oiling, textile and many other industrial products with little or no impact on iron pollution. It is applicable to low-pressure valves with working temperature between – 15 ~ 200 ℃ and nominal pressure PN ≤ 1.6Mpa.
2. Nodular cast iron
Nodular cast iron is a kind of cast iron. This kind of cast iron, mass or spherical graphite replaces the flake graphite in gray cast iron. The change of the internal structure of this metal makes its mechanical properties better than ordinary gray cast iron, and does not damage other properties. Therefore, valves made of nodular cast iron have higher service pressure than those made of gray cast iron. It is applicable to medium and low pressure valves with working temperature between – 30 ~ 350 ℃ and nominal pressure PN ≤ 4.0Mpa. The applicable media are water, seawater, steam, air, gas, oil, etc.
3. Carbon steel
At first, the development of cast steel was to meet the production needs that exceeded the capacity of cast iron valves and bronze valves. However, due to the good service performance of carbon steel valve and its high resistance to stress caused by thermal expansion, impact load and pipeline deformation, its application range is expanded, usually including the working conditions of cast iron valve and bronze valve. It is applicable to medium and high pressure valves with working temperature between – 29 ~ 425 ℃. The temperature of 16Mn and 30mn is - 40 ~ 400 ℃, which is commonly used to replace ASTM A105. The applicable medium is saturated steam and superheated steam. High and low temperature oil products, liquefied gas, compressed air, water, natural gas, etc.
