904L steel tanks for International Starch Institute A/S
New material, challenging order
International Starch Institute A/S has ordered 13 tanks for various purposes. Among them were structures for which we used 904L type steel. This is an excellent opportunity to take a closer look at the specifics of the material used, according to the customer’s requirement.
The order from the Danish contractor included storage tanks, hot water tanks, starch tanks, mixers and 73m3 reactors which 904L steel was used in.
904L and 316L steel – properties, purposes and specifics
Types 904L and 316L are high-alloy stainless steels that differ in chemical constitution, mechanical properties and applications. In most of Gpi projects, we use 316 (L) and 304 (L). A project for the International Starch Institute proved to be an excellent opportunity to experiment with a new material.
The comparison of two steel types:
|
904L |
316L |
|
|
Extension strength (Rm) |
490-690 MPa |
485 MPa |
|
Yield Strength (Rp 0.2) |
≥220 MPa |
170 MPa |
|
Elongation at break |
≥35% |
≥40% |
|
Toughness |
≤ 90 HRB |
≤ 95 HRB |
904L has better corrosion resistance in extreme conditions such as highly acid environments or with high chloride content, while 316L is sufficient for less demanding environments.
904L is used in chemical, petrochemical, pharmaceutical, sulfuric acid production, marine installations and paper industry. Type 316L is appropriated in the food, pharmaceutical, medical, petroleum, offshore installations and chloride-exposed structures. 904L contains significantly more nickel and molybdenum than 316L. In addition, it contains copper, increasing corrosion resistance in acidic environments..
The decision between different steel types primarily depends on the specific environmental conditions and budget constraints. Because of its unique properties and limited availability, 904L tends to be the more expensive option.
Manufacturing
Leveraging the expertise of Gpi’s welders, the new material was seamlessly utilized on the production floor in Skarbimierz. The tanks were completed on schedule, without any complications, and successfully delivered to Denmark, where they will play a crucial role in the production process.
With capacities ranging from 4m³ to 73m³, these tanks were manufactured across two locations: Brzeg and Skarbimierz.
About the client
International Starch Institute A/S originates from the Danish potato starch industry. The company specializes in delivering turnkey factories worldwide. They process a wide agricultural crops, such as corn, wheat, potatoes, and cassava, into starch, glucose, and various derivative products for industrial applications.
