Chemicla composition for 904L stainless steel
|
Grade |
C (%) |
Si (%) |
Mn (%) |
P (%) |
S (%) |
Cr (%) |
Ni (%) |
Mo (%) |
Cu (%) |
|
904L |
≤0.02 |
≤1.0 |
≤2.0 |
≤0.045 |
≤0.035 |
19.0-23.0 |
23.0-28.0 |
4.0-5.0 |
1.0-2.0 |
Mechanical property for 904L stainless steel
|
Grade |
tensile strength Mpa |
Yield Strength Mpa |
rate of reduction in area (%) |
Density (g/cm3) |
|
904L |
≥490 |
≥216 |
--- |
8.0 |
Specifications for 904L stainelss steel
|
Technical |
Thickness |
Width |
Finish |
Origin |
|
Cold rolled |
0.3mm-3.0mm |
Standard size in China: 1219mm Special:can be order |
2B |
TISCO / Outokumpu / Japan etc
|
|
Hot rolled |
3,0mm-350mm |
Standard width in China: 1500mm Specail width:can be ordered |
No.1 |
TISCO / Outokumpu / Japan etc
|
Applications for 904L stainelss steel
1) Petroleum, petrochemical equipment, such as petrochemical equipment in the reactor, etc..
2) Sulfuric acid storage and transportation equipment, such as heat exchangers, etc..
3) power plant flue gas desulfurization device, the main use of the parts are: absorption tower body, flue, door panels, internal parts, spray systems, etc..
4) organic acid treatment system of scrubber and fan.
5) sea water treatment equipment, sea water heat exchanger, paper industry equipment, sulfuric acid, nitric acid equipment, acid making, pharmaceutical industry and other chemical equipment, pressure vessels, food equipment.
6) Pharmaceutical Plants: centrifuges, reactors, etc..
7) plant food: cans of soy sauce, cooking wine, salt, and dressing equipment.
In dilute sulfuric acid, strong corrosive medium is 904L steel.
Standards for 904L stainless steel
GB: 20Cr-24Ni-4.3Mo-1.5Cu (Standards from China)
ASTM: 904L (Standards from USA)
DIN: 1.4539 (Standards from Europe)
JIS: SUS890L (Standards from Japan)
The weight calculation method for 904L stainless steel
Weight(KG/PC)=thickness(mm) x width(Meter) x length(Meter) x 8.0
Small knowledge for 904Lstainless steel
Because 904L is a low carbon content (maximum 0.020%), so in the general case of heat treatment and welding, there will be no carbide precipitation, this eliminates the risk of heat treatment and welding in intergranular corrosion.
Due to the high content of chromium, nickel and molybdenum, and the addition of copper, 904L can also be passivated even in reduced environments, such as sulfuric acid and formic acid.
High nickel content in the active state also has a lower corrosion rate. 0~98% in the concentration range of pure sulfuric acid, the use of 904L temperature can be as high as 40 degrees celsius.
The corrosion resistance of pure phosphoric acid in 0~85% concentration range is very good. In the industrial phosphoric acid produced by wet process, impurities have a strong influence on corrosion resistance.
In all kinds of phosphoric acid, the corrosion resistance of 904L is better than that of ordinary stainless steel.
In hydrochloric acid, the use of 904L is limited to a lower concentration of 1-2%, in this concentration range, the corrosion resistance of 904L is better than that of conventional stainless steel.
904L steel has high resistance to pitting corrosion. The crevice corrosion resistance of chloride solution is also very good. The high nickel content of 904L reduces the corrosion rate in the pits and crevices.
Due to the high nickel content, 904L is highly resistant to stress corrosion cracking in chloride solution, concentrated hydroxide solution and hydrogen sulfide rich environment.
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