Valves are divided into the following materials:

1 Valve stem bushing material, its hardness and strength should not be greater than the valve stem, and under the condition of water immersion with the valve stem, valve body does not form electrochemical corrosion.

2. Material of sealing surface.

3 The nut material is cast aluminum brass or cast aluminum bronze, and the hardness and strength are greater than the valve stem.

4 Valve material, because gray cast iron pipe is gradually not recommended to use, the valve body material should be mainly ductile cast iron, and indicate the grade and the actual physical and chemical test data of the casting.

5 Valve stem material, strive to stainless steel valve stem (2CR13), large ☐ diameter valve should also be stainless steel clad valve stem.

Common materials:

The first category: cast iron

The cast iron is subdivided down, and bai has four kinds of gray cast iron, malleable du cast iron, ductile cast iron and nickel cast iron. This article mainly introduces two kinds of cast iron materials made by Taichen valve: gray cast iron and

Ductile iron.

The second category: cast steel

Cast steel is a cast iron alloy, which is a general term for iron-based alloys used in the production of castings that do not undergo eutectic transformation during solidification. The advantage of cast steel is that it has greater design flexibility

Flexibility and variability improve overall structural strength and wide range of weight variations. Casting steel is used as the material of butterfly valve, and its performance is better than cast iron but not as good as stainless steel. Butterfly valves made of cast steel are applicable

The medium is steam, non-corrosive gas, oil and so on.

The third category: stainless steel

Stainless steel refers to the steel that is resistant to weak corrosive media such as air, steam, water and chemical etching media such as acid, alkali, salt, also known as stainless acid-resistant steel. Usually stainless steel butterfly valve,

The performance is the best, can be applied to more severe conditions, in some ultra-high temperature, ultra-low temperature, acid and alkali corrosive medium pipe use, while stainless steel butterfly valve hardness

It is stronger, more resistant to wear, and has the longest service life.

The fourth category: ductile iron

It is suitable for water, steam, air, oil and other media with PNs4.0MPa and temperature of -30 ~ 350℃. Commonly used brands are: QT400-15, QT450-10, QT500-7.

In view of the current level of domestic technology, each factory is uneven, and users are often not easy to inspect. According to experience, it is recommended that PN≤2.5MPa, the valve is still safe to use steel valves.

These are some common valve materials, if you want to know more about valve materials and other knowledge, please contact our customer service staff.