What are the application characteristics of zirconium pressure vessels?

The mechanical properties and thermal conductivity of zirconium are also very good, suitable for reactor shells, heat exchanger tube sheets, tower, or pipe components, so zirconium pressure vessels are also important non-ferrous metal structure materials in petrochemical, chemical, and other industries. With the continuous development of materials science and process equipment manufacturing technology, zirconium or zirconium/steel composite plates are increasingly used in highly corrosive equipment such as acetic acid, nitric acid, sulfuric acid, urea, hydrogen peroxide, poly formaldehyde, and chlorinated polyethylene production units. Let me bring you some introduction about zirconium pressure vessels.

Here is the content list:

• What are the characteristics of zirconium

• Zirconium pressure vessel manufacturing characteristics

• Zirconium pressure vessel manufacturing characteristics

What are the characteristics of zirconium?

Zirconium comes from the Arabic argument, "gold", used to fabricate the Zirconium gem (ZrSi04). Klaproth discovered zirconium in 1789, Berzelius isolated impure zirconium in 1824, Van Arkel and de Boer produced ductile zirconium in 1924, and in 1947, Kroll produced zirconium on an experimental scale for industrial use, and in the early 1960s zirconium and titanium began to be used as preservationists. Zirconium has been commonly used in nuclear equipment in the past because of its excellent thermal neutron radiation embrittlement resistance. Zirconium pressure vessel is an active metal, which is easy to oxidize. Such as at room temperature can react with oxygen in the air, forming a layer of oxide film, the surface passivation film is dense, giving the best anti-corrosion ability, zirconium pressure vessels and zirconium alloy - set the conditions for the majority of organic acid, inorganic acid, alkali, such as molten salt have more than senior stainless steel, titanium alloy, nickel-base alloy excellent corrosion resistance.

Various applications of zirconium pressure vessels

1. Mainly used for strong corrosion resistance

Zirconium pressure vessels are mainly used as corrosion-resistant pressure vessels because of the excellent corrosion resistance of zirconium in many highly corrosive media. A typical application such as acetic acid containing halogen ion, anhydride equipment.

2. Can be used for heat exchange container

Although zirconium pressure vessels have the lowest thermal conductivity, only about a quarter of that of ordinary steel, the corrosion margin should be lower due to the corrosion resistance of zirconium or zero, which can be used with a thinner wall thick heat exchange tube. Zirconium also has a lower fouling coefficient. Zirconium is therefore often used in heat exchangers.

3. Use only industrial-grade zirconium

Zirconium pressure vessel is divided into nuclear-grade zirconium and industrial-grade zirconium. Non-nuclear industry pressure vessels do not have the requirements of radiation embrittlement, do not need to use any Expensive nuclear-grade zirconium, only the industrial-grade zirconium with lower price, China's brand is low oxygen pure zirconium ZR-1, pure zirconium ZR-3, and zirconium niobium alloy ZR-5.

4. The actual application is narrow

Because zirconium is much more expensive than other materials, zirconium is used only when other materials cannot meet the requirements of corrosion resistance Device. Zirconium also has good low-temperature resistance. There are no additional technical requirements for zirconium pressure vessels at temperatures above -60°C. At lower temperatures, it can be used up to -269C as long as the material is checked to have a satisfactory elongation at the design temperature. But because of low-temperature pressure vessels can be used. Low-temperature steel, austenitic stainless steel, aluminum, copper, and other low-temperature materials manufacturing. Expensive zirconium containers are not specialized.

For cryogenic containers. Therefore, the application of zirconium pressure vessels is relatively narrow. In recent years, the annual amount of zirconium used in pressure vessels in China is about several hundred tons.

Zirconium pressure vessel manufacturing characteristics

1. High requirements for site cleaning

Due to the high activity of zirconium pressure vessels, collision, and pollution in manufacturing will affect the performance of zirconium, so it is required to clean the site to avoid and reduce Iron contamination, especially welding sites should be independent of steel site.

2. Welding protection requirements are the highest

Due to the high activity of zirconium pressure vessels, welding at high temperature is easy to pollute the weld and heat-affected zone and must be carried out in a vacuum or under the protection of argon gas. The welding joint temperature in cooling exceeds 400C should be protected. The front and back of the weld shall be protected. Because of zirconium pressure vessels, the melting point is the highest, the thermal conductivity is the lowest, the cooling rate is the slowest, so the length of the drag cover is longer than that of other welding materials.

3. The spring-back of cold forming is larger

Zirconium pressure vessels especially zirconium alloy have the lowest elastic modulus, while zirconium yield strength is close to that of austenitic stainless steel, and ZR-5 zirconium niobium alloy. The yield strength of zirconium is higher than that of common low alloy steel Q345R, so the flexor-elastic ratio of zirconium is higher and the spring-back after cold forming is larger.

4. The conditions of heat treatment are strict after cold forming

Zirconium pressure vessels under 500℃ cold forming, fiber elongation is more than 3% should be returned. And austenitic stainless steel after cold forming- Generally do not require heat treatment, pure nickel cold forming fiber elongation & GT;10%, nickel alloy & GT; heat treatment at 7%~15%. Zirconium has more stringent requirements.

Nanjing Suntech Metal Equipment Co., Ltd. is committed to the production of zirconium pressure vessels, their products meet international standards, quality and safety, and reliability, and provide perfect after-sales service, in the industry is a leading brand. If you are interested in zirconium pressure vessels, welcome to consult the company, you will get a satisfactory reply!