Ningbo Tianyi manufactures a thousand-ton low-temperature steel shift gas absorption tower for Zhenhai Refining & Chemical Co., Ltd
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According to Sinopec News Network, on August 28, the shift gas absorption tower for the Zhenhai base project, manufactured by Tianyi Manufacturing Company of Refining & Chemical Engineering (Group) Ningbo Engineering, was completed and successfully shipped for delivery. The main structure of this equipment is made of low-temperature steel; it has a maximum diameter of 4 meters, a maximum thickness of 96 millimeters, a total length of 99.2 meters, and a net weight of 945 tons. It is an equipment that receives special attention during construction. During the manufacturing process, faced with challenges such as heavy responsibilities, tight deadlines, substantial workload, and variable weather conditions, Ningbo Engineering Tianyi Manufacturing Workshop followed a strategy focused on overcoming obstacles and achieving high efficiency. It optimized resource allocation, strengthened quality control throughout the production process, emphasized safety in on-site operations, and mobilized all personnel involved to work hard, creating an atmosphere of urgency to meet the equipment delivery deadlines. Under the goal of \"maintaining quality, ensuring safety, and promoting production,\" all personnel involved in manufacturing worked in two shifts throughout the day, scheduling their work efficiently to improve productivity. From the date on which the pipe connection diagram was received on May 15th until the complete completion of the manufacturing process, it took less than 100 days. It is understood that the equipment arrived at Zhenhai Port on August 29, and was delivered to the designated location at the project site on August 30. The entire transportation process proceeded smoothly, creating favorable conditions for installing the necessary accessories on the equipment and lifting it into place on time.
Stees for low temperature service are alloy steels suitable for use at temperatures below 0°C. Those that can be used at temperatures below -196°C are called cryogenic steel or ultra-low temperature steel. Low-temperature steels should primarily possess the following properties: ① a toughness-to-fracture transition temperature lower than the operating temperature; ② strength that meets the design requirements; ③ a stable microstructure at the operating temperature; ④ good weldability and formability; ⑤ for certain special applications, extremely low magnetic permeability, cold shrinkage rate, and other characteristics are also required. Low-temperature steels can generally be divided into two main categories based on their crystal lattice type: body-centered cubic ferritic low-temperature steels and face-centered cubic austenitic low-temperature steels.
In petroleum gas cryogenic separation equipment, the minimum operating temperature for most low-temperature steels is -110°C; in some devices it reaches -150°C. For such applications, low-alloy steels, steels containing 3–6% nickel, or steels containing 9% nickel can be used. In air separation equipment, where the lowest operating temperature reaches -196°C, 9% nickel steel or austenitic low-temperature steel is generally used. Equipment for the production, storage, and transportation of liquid hydrogen, which operates at a temperature of -253°C, as well as equipment for liquid helium operating at a temperature of -269°C, should all be made of austenitic low-temperature steel with a stable structural organization. For certain special devices such as superconducting magnets or superconducting motors, it is advisable to use steel grades that, in addition to having a stable austenitic structure at operating temperatures, can also maintain an extremely low magnetic permeability (μ) of ≤1.01 or even lower. Some iron-nickel and nickel-based superalloys with high low-temperature toughness, such as A-286, Inconel 718, and Inconel X-750, are also commonly used in low-temperature equipment that requires high strength.
What kind of device is a converted gas absorption tower?